# Heating with Thermal Storage and Low Flow Temps



## JohnDolz (Jan 12, 2016)

I'm not sure if this topic has been beaten to death yet or not. I am still really new here but am very impressed with some of the knowledge, engineering and equipment out there. I'm happy to see the amount of info around Thermal Storage design and piping but I haven't seen anything about leveraging a mixing valve to get better "mileage" out of the storage. I have attached a few pictures, as a long time Hearth Member educated me that seeing goes a long way. One photo is of my Shunt Valve Controller (everything is in Celsius). This system is controlled by an Outdoor Reset (see Heat Curve Photo) but has the ability to be overridden by an Indoor Sensor should the Temp vary too far from target either way. 

I have the Indoor Sensor upstairs as upstairs is 1 big heating loop. The Heat Curve I have chosen to use gets me to about 70F Upstairs and with the help of thermostats keeps my downstairs (2 loops) at 72F.

My boiler controls this stuff but I understand that there are controllers that can do this as long as you have storage. I have been asked about my emitters so I have included a photo of these as well. They are standard baseboard with some aftermarket covers for looks. My plumbers swears I am losing 30-40% of BTU power due to these covers. I also have a Modine Hydronic Heater heating an unfinished basement.

I have chosen a Heat Curve of 52. If you look at the heat Curve graph and look at the curve that intersects 50C and -15C, just shift it up 2 degrees and that is what I am tracking.

To tie this info to something, I am heating about 5000 sqft (includes a 1500 sqft basement at 67F & a 500 sqft addition with an UNDER powered toe heater) and keep the house at 70 -72 as described. Looking at the Shunt Control you see that the Outdoor temp is 1C (34F) and that my target flow temp is 40C (104F); at the moment of the photo actual is 37C (99F). The whole day was about 34F with no sun. I started a fire this AM around 7:00 AM (65kw = 200k btu hr) and got the top tank to 190F. It is now a little after 6:00 PM and top tank is at 181F. 

This is VERY different from last year where I felt I was always pressing to charge tanks. I'm curious as to others experiences.


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## TCaldwell (Jan 12, 2016)

Hi John, 
 I'm not surprised only alot jelous, heating your house with what my system would consider useless. After seeing your setup with your emitters, I spoke to several mechanical engineers that specialize in hydronic design and by the way participate here. All three stated outdoor reset with indoor feedback being supplied from storage would be able to satisfy the house demand with lower water temps, these lower  water temps would increase the useable storage. This is possible because a properly designed reset system's circs seldom shut off, always delivering the minimun heat required to maintain temp with no on/off wasted energy or cold spots. One engineer stated that as well as the system works with suspect emitters, he would start with changing to low temp emitters first to reduce system flow, then employ reset for further savings. In any case weather the cart before the horse does not matter, this appears for a older guy a way to handling less wood!
 I was also informed that us boiler manufacturers will soon be federally mandated to incorporate odr.


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## cpeltier (Jan 12, 2016)

JohnDolz said:


> I haven't seen anything about leveraging a mixing valve to get better "mileage" out of the storage.



This is indeed one strategy. The ideal situation is to pick off the coolest temperature from your storage that will work for your current outdoor reset heating curve point but since this can get complicated a floating action mixing valve or injection pump (which I use) go a long way to maximize the high temp water in storage.


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## JohnDolz (Jan 12, 2016)

cpeltier said:


> This is indeed one strategy. The ideal situation is to pick off the coolest temperature from your storage that will work for your current outdoor reset heating curve point but since this can get complicated a floating action mixing valve or injection pump (which I use) go a long way to maximize the high temp water in storage.


Thanks for the input. I had to go to PexUniversity (via Google) to get an understanding of what you are doing with an injection pump. Pretty much the same result as a shunt valve. Are you changing your target temp via some type of controller or simply zeroed in on the lowest temp that will meet your needs at target that? PexU made reference to Greenhouses, I happen to have talked to a local greenhouse that is installing a beautiful huge woodchip boiler with storage and he gave me a little education on mixing. I never gave it thought before but he pointed out that with thermal gain and radiant floors running low temp is critical for them..


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## JohnDolz (Jan 12, 2016)

TCaldwell said:


> Hi John,
> I'm not surprised only alot jelous, heating your house with what my system would consider useless. After seeing your setup with your emitters, I spoke to several mechanical engineers that specialize in hydronic design and by the way participate here. All three stated outdoor reset with indoor feedback being supplied from storage would be able to satisfy the house demand with lower water temps, these lower  water temps would increase the useable storage. This is possible because a properly designed reset system's circs seldom shut off, always delivering the minimun heat required to maintain temp with no on/off wasted energy or cold spots. One engineer stated that as well as the system works with suspect emitters, he would start with changing to low temp emitters first to reduce system flow, then employ reset for further savings. In any case weather the cart before the horse does not matter, this appears for a older guy a way to handling less wood!
> I was also informed that us boiler manufacturers will soon be federally mandated to incorporate odr.


Hi Tom - Thanks but I have no doubt that in no time you will far surpass what I am doing and I will be the jealous one. The cost of the low temp emitters caused me to think I would just run constant flow through my existing emitters and see what happens. I believe the difference is just more lineal feet of tubing and fins but I can be wrong. I have an addition that is powered by a toe heater, TERRIBLE! I am thinking to put more horsepower in there with a low temp emitters or possibly a minisplit because I have the opposite problem in the summer (solar). I look forward t learning what you decide to do and hearing your results.


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## cpeltier (Jan 12, 2016)

JohnDolz said:


> Are you changing your target temp via some type of controller or simply zeroed in on the lowest temp that will meet your needs at target that?



I'm using the outdoor temperature to calculate the target temperature of my mixing system (for radiant) and modulate this using an injection pump via a PID loop. I have fan coils in the system which I also run at 125F (lowest temp that worked for my setup) and this is also controlled by another PID injection pump. I use a primary/secondary loop strategy and it extracts every BTU out of my 750 gallons of pressurized storage with excellent stratification. It is all controlled by a very powerful EasyIO FG32+ controller with web based control and full HTML 5 animated graphics. All very cool. It's all part of a much larger system that I can go into more detail if you like.


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## JohnDolz (Jan 12, 2016)

cpeltier said:


> I'm using the outdoor temperature to calculate the target temperature of my mixing system (for radiant) and modulate this using an injection pump via a PID loop. I have fan coils in the system which I also run at 125F (lowest temp that worked for my setup) and this is also controlled by another PID injection pump. I use a primary/secondary loop strategy and it extracts every BTU out of my 750 gallons of pressurized storage with excellent stratification. It is all controlled by a very powerful EasyIO FG32+ controller with web based control and full HTML 5 animated graphics. All very cool. It's all part of a much larger system that I can go into more detail if you like.


VERY impressive, thank you for sharing. I would love to hear more but I caution you tat it is over my head already - but I am working on learning. I am in Sales and happen to cover PA maybe we can meet one day. I'll trade you some home roasted coffee for a our and lecture.  Safe to bottom line it as you believe low flow temp is the way to go?


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## maple1 (Jan 13, 2016)

What would your typically daily burning schedule look like?


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## cpeltier (Jan 13, 2016)

JohnDolz said:


> but I am working on learning. Safe to bottom line it as you believe low flow temp is the way to go?



A great information resource that others have mentioned in this forum is located here: http://www.nyserda.ny.gov/-/media/Files/EERP/Renewables/Biomass/biomass-hydronics-training.pdf

To maximize the use of storage and maximize efficiency (in many different ways) it is ideal to operate your system at the lowest effective temperatures. Of course you want your storage to be as hot as possible to maximize stored BTUs. Doing this with storage can be tricky as you must do this in a way where you also minimize the return temperatures and prevent storage tank mixing. It is very important to maintain tank stratification. 

Hi Maple1, I'm not sure if your asking me but I burn twice a day in the colder weather (last night 17F). When I wake up, and in the evening. Last night storage ran out (750 gallons) before I had a chance to fire and the LP boiler + HP kicked in.


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## maple1 (Jan 13, 2016)

I guess I was first asking John, but all input welcome though.

So how many hours of burning does that represent? Storage temps top & bottom at start & end of burn?

I changed my habits last year as I also read then observed first hand that lower temps = less wood burned. I don't do any mixing though, I just deplete my storage before I burn. Depleted = when the house can no longer maintain temp.

So typical for me would be burning 6 hours a day during the winter. Storage would be around 125/115 beginning (depending how cold & windy it is out), maybe 180/170 ending - again depending what the next 12-24 hours weather forecast is sounding like. Or thereabouts. 2700 sq.ft 20 year old two storey over 1500 unfinished basement, Slant Fin baseboard (likely more than needed for a more typical oil heat system). I don't think mixing would gain me much or be worth the work in making the changes unless I updated my emitters - but even then I'm not sure it would be worth it as I should just be able to put off lighting until storage was a bit cooler. I am thinking either way I would need to be lighting when my storage was at about the same point of depletion.


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## cpeltier (Jan 13, 2016)

maple1 said:


> I guess I was first asking John, but all input welcome though.
> 
> So how many hours of burning does that represent? Storage temps top & bottom at start & end of burn?



Didn't mean to thread hijack. I'm curious what John is seeing as well.

I have a Termovar mixing valve on wood boiler and it effectively creates a 2 step tank charging process. The first run fills the tanks (750 gallon) with 165F water because the return water to the boiler (Termovar) is cold. When the Termovar sees the high return temp because the tank is full then the boiler output jumps to 185-190F and it charges again to this higher temp. If it's not that cold a half load in the boiler will charge it to 165. A full load does 180-185 depending on house load. I found this behavior to be interesting.

In the last 24 hours, two runs of about 3.5 hours each (~7 hours total). I was seeing 115/115 when depleted and 180/180 typically when full. My fan coil load wants to see at least 125F in the tanks or it will switch over to LP. The radiant load will take the storage all the way down to as low as 80/70 if I allow it depending on outdoor temps (follows an outdoor reset curve). When the tank runs out for the fan coil the fan coil and radiant load will keep pulling the tank lower so the tank temps when depleted can be all over the place depending on when I catch it. When the LP turns on below 125F the storage tanks will still assist where it can to boost the return temps from the fan coils before presented to the modulating LP boiler (8-1 turndown). The average outdoor temp in the last 24 hours was about 25F and it's a 5500 square foot house (25 years old) including a heated walk out basement.

I agree lower temps = less wood burned. Switching to pressurized storage (from a worn out unpressurized) seems to have cut my wood use down as I can extract more heat out of the storage (no delta T loss in HX) and charge hotter. I also added turbulators to my Tarm last season and that helped a lot! The combination of modifications may have cut my wood use in half!

Your 125F/115F sounds very good for the Slant Fin baseboard. I probably wouldn't touch a thing!


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## maple1 (Jan 13, 2016)

*Your 125F/115F sounds very good for the Slant Fin baseboard. I probably wouldn't touch a thing!*

Yes, it does pretty good. There was a heat loss done when I was building by a pro, and the baseboard was sized for that. I don't think I ever saw the heat loss paperwork & have no idea what happened to it (I think the installer kept it), but I am quite sure he oversized it. Which I am now quite grateful for. I did add a short section to one upstairs bedroom in a north corner a few years ago after complaints from one of my kids, and another couple very short sections at strategic spots in my downstairs office. I have a couple of spots picked out for cast iron rads if I can convince my other half - and I could 'fairly easily' add more Slant Fin if I wanted as most rooms were put in wall to wall with the enclosure.

But when it gets to the coldest days of winter, into the -20's c cloudy maybe with some wind mixed in - I am for sure heading to light before storage gets below 140.


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## JohnDolz (Jan 13, 2016)

cpeltier said:


> A great information resource that others have mentioned in this forum is located here: http://www.nyserda.ny.gov/-/media/Files/EERP/Renewables/Biomass/biomass-hydronics-training.pdf
> 
> To maximize the use of storage and maximize efficiency (in many different ways) it is ideal to operate your system at the lowest effective temperatures. Of course you want your storage to be as hot as possible to maximize stored BTUs. Doing this with storage can be tricky as you must do this in a way where you also minimize the return temperatures and prevent storage tank mixing. It is very important to maintain tank stratification.
> 
> Hi Maple1, I'm not sure if your asking me but I burn twice a day in the colder weather (last night 17F). When I wake up, and in the evening. Last night storage ran out (750 gallons) before I had a chance to fire and the LP boiler + HP kicked in.


Yes I have seen that document, full of great information - wish I had read it 2 years ago I would have done a few things differently. At this point I am making the best of what I have and overall I am VERY happy.


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## JohnDolz (Jan 13, 2016)

cpeltier said:


> Didn't mean to thread hijack. I'm curious what John is seeing as well.
> 
> I have a Termovar mixing valve on wood boiler and it effectively creates a 2 step tank charging process. The first run fills the tanks (750 gallon) with 165F water because the return water to the boiler (Termovar) is cold. When the Termovar sees the high return temp because the tank is full then the boiler output jumps to 185-190F and it charges again to this higher temp. If it's not that cold a half load in the boiler will charge it to 165. A full load does 180-185 depending on house load. I found this behavior to be interesting.
> 
> ...


I haven't quite figured out my burn cycle as things are different for me. I was thinking 1 burn a day in the milder and 2 burns a day now that it is colder. So far 2 burns has been too much so If temps were in the 20's/30's I think an average of 1.5 burns would do it. When we were in the 40's/50's I was doing 1 burn every 3 days or so. Another thing I am thinking about and trying to time is letting my tanks run down in the 120 range and then doing 1.5 loads to get the tanks charged. My thought is reducing the # of fires I start in order to minimize the # of ramp up/ramp down's. The risk is that the lower the top tank temp gets the faster it drops so when you start getting to low #'s it can bottom out pretty quick. Last year I had my setpoint at 145 for propane boiler to kick in. This year I am at 110 and think I was at 100 earlier in the winter.


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## Kristen (Jan 13, 2016)

My system is sized for one burn per day.  If it is 10 degrees colder than normal (i.e. what we would normally call "cold", and 10 degrees lower than that we only get once or twice a decade) then I have to burn twice a day.

We aim to finish a burn as we go to bed so that the house is warm and the storage tanks are at max temperature. A full burn, of good, dry, hardwood) takes about 7-8 hours. In the morning the tank will provide heat for getting up, and to warm the house a bit during the day until the boiler is lit again around 3pm. If we get a bit of sunshine we get some solar gain from the windows, and are less likely to need top-up heat from storage. If it is grey, and miserable, the heating will come on during the day.

Tank temperature range is 40-90C / 105-195F. Down at the bottom end the heating is only any good for topping up during the day, when it is not seriously cold outside, which is fine most of the time as the boiler is lit at 3PM and in the 3 hours before that we have maximum chance of solar gain from the sun.  Late into the evening, and first thing in the morning, we benefit from the tank temperature being at the top end, which heats the house faster (or combats colder out door temperatures  )

So far this winter we have had very mild weather.  I have been burning every-other-day.  Generally on the in between day the storage tank is at 60C / 140F in the evening.  So long as the following morning is mild that is enough to give me morning heat, following day, and then by 3PM the tank will be down to 40C / 105F.  If I think the following morning will be cold then I may do a half-load, but I find that a full-load is much more efficient - some heat is wasted bringing boiler and everything else up to best operating temperature.

Only downside to every-other-day burns is that there is not enough domestic hot water, so the immersion heater, in the DHW tank, will come on overnight (we have cheaper electricity at night).


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## JohnDolz (Jan 13, 2016)

Kristen said:


> My system is sized for one burn per day.  If it is 10 degrees colder than normal (i.e. what we would normally call "cold", and 10 degrees lower than that we only get once or twice a decade) then I have to burn twice a day.
> 
> We aim to finish a burn as we go to bed so that the house is warm and the storage tanks are at max temperature. A full burn, of good, dry, hardwood) takes about 7-8 hours. In the morning the tank will provide heat for getting up, and to warm the house a bit during the day until the boiler is lit again around 3pm. If we get a bit of sunshine we get some solar gain from the windows, and are less likely to need top-up heat from storage. If it is grey, and miserable, the heating will come on during the day.
> 
> ...


DHW does make things a little tricky. I ran out of runway this year but I am going to install a separate DHW loop with its own circulator pump and shunt valve. This will allow DHW demand to be answered at a different water temp than my CH. I use an Indirect Water heater (basically an insulated storage tank) and will have 2 probes going into it. One will be set at say 125F and will pull water from my storage to meet demand. The other will be set at 120 and be connected to my propane boiler. When DHW target flow temp cannot be met by my wood system the controller will turn that pump off (basically not answering the call). The when DHW drops to 120 the call will go out to my propane boiler. That is the theory anyway.


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## maple1 (Jan 13, 2016)

I have an ordinary 80 gallon electric water heater. I heat it with wood via a flat plate HX (and a small B&G Ecocirc on the DHW side), as another load zone. I also use a Johnson A419 controller to control it with. The A419 has a separate function that when a certain circuit is closed on it (or more exactly when that circuit gets 24v sent through it, as a thermostat circuit would), it shifts its setpoint by a certain programmable amount. I have not rigged it all up yet 'done done' - but I have a thermal switch I plan to fasten to my boiler return line just outside the boiler, under some pipe insulation. Tied to 24volts & wired through that certain A419 circuit. The end result of all that, is that when the boiler is burning and hot, my DHW heater would automatically charge up to a certain programmable amount beyond what it normally would heat to. I did have it rigged up once but the thermal switch I was using was wonky, it wouldn't go fully open. So I now 'for now', just have that circuit going through a normal light switch switch - if I want to 'charge' my DHW tank, I just flip the switch when I start a fire, then flip it the other way a couple hours later. I don't need to do that when burning for heat every day or two, but it extends my DHW range quite a bit if burning only for DHW. If I charge my DHW tank to 160, it will keep us in hot water for a couple or three days on its own before needing more charge. Now, in winter, it sits at around 125 most of the time.

So, using something like that would take some of the urgency about having to keep your storage water hot enough to make DHW all the time.


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## Kristen (Jan 13, 2016)

JohnDolz said:


> I am going to install a separate DHW loop with its own circulator pump and shunt valve



We had a coil at the top of the Thermal Store which provided DHW in our first year. That needed top of store to be 65C / 150F minimum, which was OK in Winter but difficult in Summer with only our Solar Panels heating the huge store tank!

We now have separate DHW tank. Boiler heats DHW tank before Thermal Store, so it heats up quickly. (Solar Panels also heat the DHW tank, and then the STore (in Summer). We are now using the original coil in the Thermal Store as a pre-heat for mains water replenishing the DHW tank, so in principle the feed to the DHW tank is about 60C (unless the store is very cold).  Seems to work well, but the DHW tank standing losses are more than the thermal store, hence the immersion top-up some days.

I don't think it would be worthwhile trying to "heat" my DHW tank from my thermal store, but I suppose with a suitable differential thermostat I could pump the contents of the DHW tank through the top coil in the thermal store when DHW < 65C and Thermal Store is more than, say, 10C warmer than the DHW tank.

I'd need some convincing though ... I hate adding complexity to my system ... "_more things to go wrong_" !!


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## JohnDolz (Jan 13, 2016)

Kristen said:


> We had a coil at the top of the Thermal Store which provided DHW in our first year. That needed top of store to be 65C / 150F minimum, which was OK in Winter but difficult in Summer with only our Solar Panels heating the huge store tank!
> 
> We now have separate DHW tank. Boiler heats DHW tank before Thermal Store, so it heats up quickly. (Solar Panels also heat the DHW tank, and then the STore (in Summer). We are now using the original coil in the Thermal Store as a pre-heat for mains water replenishing the DHW tank, so in principle the feed to the DHW tank is about 60C (unless the store is very cold).  Seems to work well, but the DHW tank standing losses are more than the thermal store, hence the immersion top-up some days.
> 
> ...


I will be the first to admit that chasing the DHW is more of fun project vs. ROI. I know I can keep it warm enough for my needs with storage temp as low as 140F, we will see how low I can go once I have this all hooked up. As mentioned I also have it tied to my propane boiler and use its Antilegionella function to make sure I kick over 140F every 14 days - target temp in Indirect DHW is 125F. In the summer I shut down the wood boiler and just let my propane boiler heat DHW. I have recently installed a solar system for electricity so at some point I may explore the value of leveraging electricity.


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## JohnDolz (Jan 13, 2016)

Kristen said:


> We had a coil at the top of the Thermal Store which provided DHW in our first year. That needed top of store to be 65C / 150F minimum, which was OK in Winter but difficult in Summer with only our Solar Panels heating the huge store tank!
> 
> We now have separate DHW tank. Boiler heats DHW tank before Thermal Store, so it heats up quickly. (Solar Panels also heat the DHW tank, and then the STore (in Summer). We are now using the original coil in the Thermal Store as a pre-heat for mains water replenishing the DHW tank, so in principle the feed to the DHW tank is about 60C (unless the store is very cold).  Seems to work well, but the DHW tank standing losses are more than the thermal store, hence the immersion top-up some days.
> 
> ...


I understand the "complexity" concern. Attached are some photos of my shunt valve & motor. As you can see it is quite simple, plumb hot water from storage and return in with a pump in front f it to pull the water through. I have a temp sensor tucked under some pipe insulation to provide flow temp. Controller sends a signal to the motor to open/close the valve. Granted it is easy for me because the controller is built into my boiler but I believe folks in the UK have been doing this for a while using an external controller.


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## velvetfoot (Jan 13, 2016)

Give me a little time to digest.  Appreciate the pics.


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## velvetfoot (Jan 13, 2016)

maple1 said:


> I don't do any mixing though, I just deplete my storage before I burn. Depleted = when the house can no longer maintain temp.


You need a sensor, perhaps hooked up to odr, that will beep upstairs when it's time to load wood before things get too cold, and taking into account outdoor temperature.  The machine being turned on will be you, as you drag yourself down the stairs.  



maple1 said:


> a small B&G Ecocirc on the DHW side


For clarity, that's a stainless pump circulating dhw through the flat plate?

That Effecta is quite the cat's meow!  That one screen shot is a screen that came with the boiler?

The other cat's meow thing is that controller of cpeltier!  Did you put that together yourself?  It's awesome.


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## maple1 (Jan 13, 2016)

*For clarity, that's a stainless pump circulating dhw through the flat plate?*

Brass, actually. It's a B&G Ecocirc E^3, model LHB08100104. A sweet little pump.


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## JohnDolz (Jan 14, 2016)

velvetfoot said:


> You need a sensor, perhaps hooked up to odr, that will beep upstairs when it's time to load wood before things get too cold, and taking into account outdoor temperature.  The machine being turned on will be you, as you drag yourself down the stairs.
> 
> 
> For clarity, that's a stainless pump circulating dhw through the flat plate?
> ...


Yes that screen is standard product. It does exactly what I want it to do with minimal work, which is perfect because I travel quite a bit and it is 1 push of 1 button for my wife to fire it up. All I have to do is make sure there is enough wood inside the basement and my wife can handle it from there. There is a tremendous amount of knowledge on this forum and some amazing systems but my wife (and probably me) would never be able to handle them.


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## JohnDolz (Jan 14, 2016)

velvetfoot said:


> You need a sensor, perhaps hooked up to odr, that will beep upstairs when it's time to load wood before things get too cold, and taking into account outdoor temperature.  The machine being turned on will be you, as you drag yourself down the stairs.
> 
> 
> For clarity, that's a stainless pump circulating dhw through the flat plate?
> ...


Just noticed where you are located. I went to RPI and am sitting in the Marriott on Wolf road as we speak. If you ever want to come take a look just let me know, I am less than 2 hour drive from you.


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## velvetfoot (Jan 14, 2016)

Will do.  You could come by and look at my setup too while you're here.  Message me if you want to.


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## cpeltier (Jan 14, 2016)

velvetfoot said:


> The other cat's meow thing is that controller of cpeltier!  Did you put that together yourself?  It's awesome.



I put the controller together or rather integrated it. Fairly straight forward, nothing terribly complicated. The programming is done via an Object Oriented graphical editor. It allows for rapid programming and it's very intuitive. You basically drag and drop objects on a screen and connect them together with your mouse like wires to define your logic flow. You can also program your own objects in a C++/java like language called Sedona that can then be dropped into your screen. I wrote a custom object to talk to my Pentair/Easytouch Pool control system and it works great. 



velvetfoot said:


> You need a sensor, perhaps hooked up to odr, that will beep upstairs when it's time to load wood before things get too cold



I was thinking of adding an email object (built into product) so that it will send me an email (to my IPhone) when the BTUs in the storage tank are low and the system needs reloading. I also thinking of having it send me an SMS text which could be easily done through an email gateway.  I monitor it now from a web page but then you constantly have to check. Another idea is to put a wall mounted Android tablet upstairs with an animating graphical (web) display, or something as small as an Iphone with a single tank BTU dial on it.


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## cpeltier (Jan 14, 2016)

velvetfoot said:


> The other cat's meow thing is that controller of cpeltier!  Did you put that together yourself?  It's awesome.



I put the controller together or rather integrated it. Fairly straight forward, nothing terribly complicated. The programming is done via an Object Oriented graphical editor. It allows for rapid programming and it's very intuitive. You basically drag and drop objects on a screen and connect them together with your mouse like wires to define your logic flow. You can also program your own objects in a C++/java like language called Sedona that can then be dropped into your screen. I wrote a custom object to talk to my Pentair/Easytouch Pool control system and it works great.



velvetfoot said:


> You need a sensor, perhaps hooked up to odr, that will beep upstairs when it's time to load wood before things get too cold



I was thinking of adding an email object (built into product) so that it will send me an email (to my IPhone) when the BTUs in the storage tank are low and the system needs reloading. I also thinking of having it send me an SMS text which could be easily done through an email gateway.  I monitor it now from a web page but then you constantly have to check. Another idea is to put a wall mounted Android tablet upstairs with an animating graphical (web) display, or something as small as an Iphone/Droid with a single tank BTU dial on it mounted in an inconspicuous place.


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## velvetfoot (Jan 14, 2016)

cpeltier said:


> I put the controller together or rather integrated it. Fairly straight forward, nothing terribly complicated.


I've gone to the website but it's not clear to me:  does the integration require assembling it onto a circuit board, soldering it on, etc?  I'm a noob when it comes to that but I'm looking for a hobby.


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## JohnDolz (Jan 14, 2016)

velvetfoot said:


> Will do.  You could come by and look at my setup too while you're here.  Message me if you want to.


Thanks for the offer, I can't do it on this trip but I will catch you next time I am in the area. Looking forward to meeting you and learning about your setup. Thanks for all the helpful information!


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## cpeltier (Jan 14, 2016)

velvetfoot said:


> I've gone to the website but it's not clear to me:  does the integration require assembling it onto a circuit board, soldering it on, etc?  I'm a noob when it comes to that but I'm looking for a hobby.


I bought it here: 
http://controlconsultantsinc.com/ea...odel-with-8gb-sd-card-preinstalled-30961.html

The data sheet is here: 
https://www.dropbox.com/s/ql5vx0cc5bjnatc/PS_FG32_v2-7.pdf?dl=0

Tons of stuff on YouTube: 
https://www.youtube.com/user/EasyIOFGBeast

CPT is the programming tool.

The unit has a DIN rail mount. I mounted mine in a metal cabinet and added DIN mount relays, terminal blocks, and a power supply. I ended up hooking the world up to it so the 32 points of IO weren't enough and I added some more I/O points using Modbus and OneWire temperature sensors:
http://www.automationdirect.com/adc/Shopping/Catalog/Field_I-z-O/Protos_X_I-z-O
https://www.embeddedarm.com/products/board-detail.php?product=TS-1700 although there are probably easier ones to use this this particular unit.

16 of the inputs will support thermistors and I used my old Tekmar sensors directly without modification. It takes a minute to bring a temperature into the programming. The outputs can control relays or 4-10ma current loop, DC 0-10V, etc.. Simplest thing I've used yet.

This is what it looked like before I started wiring it. I'll have to get a current picture.


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## velvetfoot (Jan 14, 2016)

Wow, I'm looking into this.  As I said, I need a hobby.


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## JohnDolz (Jan 14, 2016)

velvetfoot said:


> Wow, I'm looking into this.  As I said, I need a hobby.


Like I said, a lot of smart people with a lot of amazing technology. I am a bit more in the plug and play world.


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## JohnDolz (Jan 14, 2016)

I am more of a story/experience guy vs. #'s so here is a quick story. I started a fire yesterday morning at 7:00 and asked my wife to start a fire last night. She forgot and forgot again this morning. She just called me (4:00 PM) and asked if she should start a fire (tank was at 117) NOT calling to tell me that the house was freezing - it was still at 72. I know the propane did not kick in because I have the setpoint at 110. It was in the upper 20's yesterday, around 20F last night and a high of 29 today. NO way that would have happened last year when I was pulling straight from the top tank without mixing.


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## cpeltier (Jan 14, 2016)

velvetfoot said:


> Wow, I'm looking into this.  As I said, I need a hobby.



The EasyIO controller's built in webserver and graphics are great but it can be taken to another level with DGLux's visualization software. The two integrate easily. I've been thinking about doing this but haven't pulled the trigger. Too many other things to do.


The nice thing about this equipment is it's pretty much standard these days in the field (small) Building Automation System (BAS) industry. There are thousands of these units sold per year and talent in your local area that could fix or maintain it. Your not putting in a one-off system and if you ever sell the home you can safely sell it with the equipment installed. The local HVAC installer would be in trouble but a commercial BAS installer would understand it.


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## velvetfoot (Jan 14, 2016)

JohnDolz said:


> I am more of a story/experience guy vs. #'s so here is a quick story. I started a fire yesterday morning at 7:00 and asked my wife to start a fire last night. She forgot and forgot again this morning. She just called me (4:00 PM) and asked if she should start a fire (tank was at 117) NOT calling to tell me that the house was freezing - it was still at 72. I know the propane did not kick in because I have the setpoint at 110. It was in the upper 20's yesterday, around 20F last night and a high of 29 today. NO way that would have happened last year when I was pulling straight from the top tank without mixing.



36 hours seems pretty good to me.  You have a 1000 gallon tank and you know where  you started and where you ended up, average temperature wise.  I'm not sure how you would do average temperature-is the temperature gradient in the tank linear?  I think not.  Then there's issues of not perfect stratification, or whatever else.  Anyway, you could figure out, somehow, how many btus you used, which would be interesting. Perhaps your Effecta calculates this for you?


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## velvetfoot (Jan 14, 2016)

I've been observing low temp, relatively speaking, operation the last few days with my 120 gallon buffer tank (not mixing).  I have to say that trying to return from a setback is a groan.  I might start a thread on setbacks and cost savings.

(Edit:  I can't go too low because my Froling Energy Tank makes dhw with a 1.25" corrugated stainless coil that holds 11 gallons.  It works down to pretty low temps.  I turn off the zone circs at 120F and back on at 125F while the boiler is getting up to temperature.)


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## NP ALASKA (Jan 15, 2016)

JohnDolz said:


> I am more of a story/experience guy vs. #'s so here is a quick story. I started a fire yesterday morning at 7:00 and asked my wife to start a fire last night. She forgot and forgot again this morning. She just called me (4:00 PM) and asked if she should start a fire (tank was at 117) NOT calling to tell me that the house was freezing - it was still at 72. I know the propane did not kick in because I have the setpoint at 110. It was in the upper 20's yesterday, around 20F last night and a high of 29 today. NO way that would have happened last year when I was pulling straight from the top tank without mixing.


Im looking forward to see if I can get such reprots from the wife


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## JohnDolz (Jan 15, 2016)

velvetfoot said:


> I've been observing low temp, relatively speaking, operation the last few days with my 120 gallon buffer tank (not mixing).  I have to say that trying to return from a setback is a groan.  I might start a thread on setbacks and cost savings.
> 
> (Edit:  I can't go too low because my Froling Energy Tank makes dhw with a 1.25" corrugated stainless coil that holds 11 gallons.  It works down to pretty low temps.  I turn off the zone circs at 120F and back on at 125F while the boiler is getting up to temperature.)


I know I mentioned it somewhere on this thread or another but yes return from a setback is a MAJOR groan. My system uses and Indoor Room Sensor that overrides the Outdoor Reset and will raise the flow temp to drive the Recovery period (usually 20 degrees F or so over the Outdoor Reset target) but even with that it takes a long time. At the end, I am not sure it is worth it.


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## JohnDolz (Jan 15, 2016)

NP ALASKA said:


> Im looking forward to see if I can get such reprots from the wife


Bring her here, you and I can split some wood, my wife can work with her on reporting.


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## JohnDolz (Jan 15, 2016)

velvetfoot said:


> 36 hours seems pretty good to me.  You have a 1000 gallon tank and you know where  you started and where you ended up, average temperature wise.  I'm not sure how you would do average temperature-is the temperature gradient in the tank linear?  I think not.  Then there's issues of not perfect stratification, or whatever else.  Anyway, you could figure out, somehow, how many btus you used, which would be interesting. Perhaps your Effecta calculates this for you?


Not sure how you would do average temp (the Effecta does not do this). I have the ability to measure top of top tank, top of lower tank and bottom of bottom tank temps but I haven't done anything with them other than use them as a gauge to know about ow much buring I can do if I want to get to 190 or so.


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## maple1 (Jan 15, 2016)

JohnDolz said:


> I know I mentioned it somewhere on this thread or another but yes return from a setback is a MAJOR groan. My system uses and Indoor Room Sensor that overrides the Outdoor Reset and will raise the flow temp to drive the Recovery period (usually 20 degrees F or so over the Outdoor Reset target) but even with that it takes a long time. At the end, I am not sure it is worth it.


 
That's something else that I see here that indicates my baseboard was oversized when it was put in. I can recover from setback pretty good. If I'm the only one home during the day (which is 90% of the weekdays here), our upstairs (bedroom) zones are set back to 16c. The thermostats up that to 20c around supper time, and it is 20c up there a couple hours later. The stats back down from 20 to 18 for overnight, at 11pm. I usually use setbacks on all of our zones at certain times to extend my storage mileage. Our largest zone has the kitchen on it. It is set to 20c from 5pm until 11pm. Then sets back to 16c until 6am. Ups to 18c until 7:30am. It's usually 7am before someone makes it down there, by then after an hour of heating it is feeling warm, temp usually shows 17c or 18c. That's if I let the stats do what I have them programmed to do - I will also quite often bump them up manually a degree in the evenings or when burning, especially the kitchen one, to put more heat in the house. So I 'set ahead' some also. Our 4th zone has the living room & my office on it, with a manual stat. I drop it a couple degrees on the way to bed, then up it as needed during the day.

If we're gone for the day and I need to heat the whole place up at once (could be from 2c to 4c) when we get back when I get a fire going, I don't have much if any boiler water going to storage for the first couple of hours. But by then the house is pretty well up to temp and water starts going to storage.


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## JohnDolz (Jan 15, 2016)

maple1 said:


> That's something else that I see here that indicates my baseboard was oversized when it was put in. I can recover from setback pretty good. If I'm the only one home during the day (which is 90% of the weekdays here), our upstairs (bedroom) zones are set back to 16c. The thermostats up that to 20c around supper time, and it is 20c up there a couple hours later. The stats back down from 20 to 18 for overnight, at 11pm. I usually use setbacks on all of our zones at certain times to extend my storage mileage. Our largest zone has the kitchen on it. It is set to 20c from 5pm until 11pm. Then sets back to 16c until 6am. Ups to 18c until 7:30am. It's usually 7am before someone makes it down there, by then after an hour of heating it is feeling warm, temp usually shows 17c or 18c. That's if I let the stats do what I have them programmed to do - I will also quite often bump them up manually a degree in the evenings or when burning, especially the kitchen one, to put more heat in the house. So I 'set ahead' some also. Our 4th zone has the living room & my office on it, with a manual stat. I drop it a couple degrees on the way to bed, then up it as needed during the day.
> 
> If we're gone for the day and I need to heat the whole place up at once (could be from 2c to 4c) when we get back when I get a fire going, I don't have much if any boiler water going to storage for the first couple of hours. But by then the house is pretty well up to temp and water starts going to storage.


I think setback/recovery is a thread of its own and I would think has been deeply discussed somewhere. On the surface it seems to make sense but as I watch my boiler adjusting to accommodate the recovery I clearly see how much extra energy is required to do so. The you add in the discomfort factor (furniture gets cold, etc.). One of the things I committed to myself (and promised my wife) as I headed into this adventure is that our house would be warm. If it takes a little extra wood so be it.


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## TCaldwell (Jan 15, 2016)

JohnDolz said:


> I know I mentioned it somewhere on this thread or another but yes return from a setback is a MAJOR groan. My system uses and Indoor Room Sensor that overrides the Outdoor Reset and will raise the flow temp to drive the Recovery period (usually 20 degrees F or so over the Outdoor Reset target) but even with that it takes a long time. At the end, I am not sure it is worth it.


Maybe more emitters as maple has would help


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## JohnDolz (Jan 15, 2016)

TCaldwell said:


> Maybe more emitters as maple has would help


Possibly but I don't have much wall space left for any more baseboard. In my case though I don't think it would matter because my controller is controlling the flow temps. If I had more emitters I think I would be using a somewhat lower heat curve which means I would have lower flow temps than I have now so I think I would be back at the same exact place. Someone good with details could probably do the BTU's saved vs. the extra BTU's used to recover and determine what % benefit, if any, there is associated with setback and recovery.


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## TCaldwell (Jan 15, 2016)

Also John's house even though he has fin tube might be pretty tight with enough radiation for all this to work. I think outdoor reset with indoor feedback's success from storage is dependent on enough radiation and a relatively tight house, that should be first looked at.


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## JohnDolz (Jan 15, 2016)

TCaldwell said:


> Also John's house even though he has fin tube might be pretty tight with enough radiation for all this to work. I think outdoor reset with indoor feedback's success from storage is dependent on enough radiation and a relatively tight house, that should be first looked at.


Honestly my recovery takes longer than I would like. I often think about not using it but since I have the Energy Saver feature built in the little kid in me wants to use it.


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## maple1 (Jan 15, 2016)

*I think outdoor reset with indoor feedback's success from storage is dependent on enough radiation and a relatively tight house, that should be first looked at.*

Yes, also plays a big part.

Ours is fairly decent, 20 year old construction (2x6 studs, housewrap...). Good southern exposure for solar gain too. But we really notice the increased heating load when the wind blows - and we get it whenever it blows & wherever it comes from. Last night it was 'only' -15c or so - but breezy. I will be lighting before noon today, for sure - didn't quite charge up enough yesterday also. I'm already down to 138/131.


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## velvetfoot (Jan 15, 2016)

JohnDolz said:


> I think setback/recovery is a thread of its own and I would think has been deeply discussed somewhere.


I think it might need further discussion from a low flow temp perspective.  I don't remember too much of that.


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## TCaldwell (Jan 15, 2016)

It sure would be helpful for one of the "engineers" to Explain the how's and whys of outdoor reset with indoor feedback with respect to being drawn from storage, system requirements ect. If John can run his house down to the stick your finger in it temps, as I have witnessed, I'm all ears for some real information. For me, I'm expanding on radiation to lower system temp requirements and flow then install odr with indoor feedback


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## maple1 (Jan 15, 2016)

TCaldwell said:


> It sure would be helpful for one of the "engineers" to Explain the how's and whys of outdoor reset with indoor feedback with respect to being drawn from storage, system requirements ect. If John can run his house down to the stick your finger in it temps, as I have witnessed, I'm all ears for some real information. For me, I'm expanding on radiation to lower system temp requirements and flow then install odr with indoor feedback


 
What do you have now for radiation? And wondering if you've tried letting storage temps drop until your house starts losing temp to see what that point really is for your situation? (Might have to do that multiple times to get a better idea where that point is). It was a gradual thing for me, getting to the lows I see now.

I have an iron ring on my finger & degree on my wall, but it had nothing to do with this stuff, and I steered a slightly different course so don't have a stamp to go with it anyway. So afraid I'm out for that - lol.


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## TCaldwell (Jan 15, 2016)

Maple, your a "engineer"


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## velvetfoot (Jan 15, 2016)

I are too a engineer.


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## Woodfarmer1 (Jan 15, 2016)

Well I'm not an engineer, so John in laymans terms could you explain the shunt valve and do you need a controller or software for it to work. I seem to need as much heat as I can get to keep my temperatures up. I would love to heat my house on a steady diet of 100* water, but similar to maple the variables around here seem too much.
I built a timber frame with sip panels and it should be sealed up tighter than a popcorn fart, but when the wind howls it seems to come right through the walls, all my big windows probably don't help either


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## JohnDolz (Jan 15, 2016)

Woodfarmer1 said:


> Well I'm not an engineer, so John in laymans terms could you explain the shunt valve and do you need a controller or software for it to work. I seem to need as much heat as I can get to keep my temperatures up. I would love to heat my house on a steady diet of 100* water, but similar to maple the variables around here seem too much.
> I built a timber frame with sip panels and it should be sealed up tighter than a popcorn fart, but when the wind howls it seems to come right through the walls, all my big windows probably don't help either


I am far from an engineer and can barely handle Laymans terms but let me try.

The shunt valve is just a mixing valve. Water from the top of the tank comes in 1 side. Water from the supply return comes in the other side and a diverter valve opens/closes to mix the 2 supplies to get the idea temp. I have a circulator pump in front of the valve "pulling" the 2 water supplies through the valve.

1. Yes you need a controller
2. It takes in 2 readings (lets forget about my 3rd/Indoor reading for now)
         a. Outdoor Reset provides outdoor temp
         b. a temperature sensor is strapped to my flow pipe just before it goes into the manifold
3. Based on the Outdoor temperature the controller chooses the ideal temperature of the flow water (see photo of heat curve) - heat curves are a function of the controller
4. The controller then adjusts the shunt/mixing valve accordingly (opening to let in more hot water from the top of the tank or closing to cause more return water to be mixed in) to hit the target temperature identified on the heat curve. The controller keeps reading the 2 temps )outdoor and flow) and keeps adjusting accordingly. Things probably function a little smoother in Europe because they don't have o many zones. My return temp varies as zones kick on and ff. When my Modine Hydronic Heater kicks on you can almost see ice cubes coming back into the return (I am starting with such low water temp that once that big blower fan gets done with it there is nothing left in the return).
5. Ideally your thermostats will be in a constant call for heat and the temperature will e exactly where you want it due to the water temperature.

Like you I have a lot of glass so I do have different parts of the house heating up differently. Interestingly in the shoulder seasons it seems like the areas with the glass are the hottest (easiest to heat); once it get cold this reverses and the "glass" zones become the toughest to heat. Hope this helps. I'd be happy to jump on a call if I have done nothing but confuse you.

As you can see above there is room for improvement but at some point (if I chase every efficiency opportunity) it will be cheaper for me just too build a new house.


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## Woodfarmer1 (Jan 15, 2016)

Fisrst entering the basement from my garn is the water hx for domestic hot water.
I have my rads plumbed into my primary with a gate valve to adjust flow to the rest of the system ( I run the primary pump 24/7 on high.)
My basement loop in slab comes next, closely spaced tee with its own pump on high with its own thermostat and mixing valve. Which I have turned on in anticipation of the cold snap to come Sunday for the next week. I still am not sure if it stores enough heat to be worthwhile as it does use a fair bit of the storage.
Then my main floor loop in floor joist also closely spaced tee with its own pump on high and thermostat which I also leave on 24/7. Then the expansion tank and primary pump, which pulls through my system and pushing the water from this point back out to the garn water hx.
I'm open to recommendations for any efficiencies?


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## maple1 (Jan 16, 2016)

Woodfarmer1 said:


> Fisrst entering the basement from my garn is the water hx for domestic hot water.
> I have my rads plumbed into my primary with a gate valve to adjust flow to the rest of the system ( I run the primary pump 24/7 on high.)
> My basement loop in slab comes next, closely spaced tee with its own pump on high with its own thermostat and mixing valve. Which I have turned on in anticipation of the cold snap to come Sunday for the next week. I still am not sure if it stores enough heat to be worthwhile as it does use a fair bit of the storage.
> Then my main floor loop in floor joist also closely spaced tee with its own pump on high and thermostat which I also leave on 24/7. Then the expansion tank and primary pump, which pulls through my system and pushing the water from this point back out to the garn water hx.
> I'm open to recommendations for any efficiencies?


 
Sounds like all your pumps are on 'high'. No idea what that translates to GPMs, but have you ever measured (accurately) all your in & out temps to see what your dTs are everywhere? Just wondering if you can lower your flows any to try to improve things. Or if you're observing any performance lows of some sort.


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## JohnDolz (Jan 16, 2016)

maple1 said:


> Sounds like all your pumps are on 'high'. No idea what that translates to GPMs, but have you ever measured (accurately) all your in & out temps to see what your dTs are everywhere? Just wondering if you can lower your flows any to try to improve things. Or if you're observing any performance lows of some sort.


i used the VERY unscientific approach of asking "doesn't slowing down flow do about the same as adding more emitters?". My "gut check" conclusion was yes so all of my pumps are on the lowest speed. No idea if it is correct and I am sure I have horrified many here that put so much thought and research into things but it works for me.


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## JohnDolz (Jan 16, 2016)

Woodfarmer1 said:


> Well I'm not an engineer, so John in laymans terms could you explain the shunt valve and do you need a controller or software for it to work. I seem to need as much heat as I can get to keep my temperatures up. I would love to heat my house on a steady diet of 100* water, but similar to maple the variables around here seem too much.
> I built a timber frame with sip panels and it should be sealed up tighter than a popcorn fart, but when the wind howls it seems to come right through the walls, all my big windows probably don't help either


Since it is a cold rainy morning I thought letting you see what the last 24 hours looked like in this environment:

1. I knew it wasn't going to be very cold so I did not max out the boiler on the last burn
2. As you can see on the shunt motor the knob is in the 1/2 way position - I still have a way to go
3. The "spikes" in the flow temperature are when my propane kicks in for DHW. This will be replumbed in the spring so that storage is heating DHW most of the time.
4. The big dip in flow temp is when I drop into energy Saver mode from 7:00 PM - 3:00 AM
5. You can see that the only time my flow water was over 50C in the last 24 hours was at 3:00 AM when my house started its recovery from setback, it then started adjusting downwards as actual room temperature got closer to target temperature. The exception to this are the spikes caused by the call for DHW (described in #3 above).
5. Bottom line is that my house has recovered to 72F and is staying there using 105F Degree water


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## velvetfoot (Jan 16, 2016)

What is interesting to me are the spikes in flow temperature, like an on/off kind of thing with a differential.  I would've thought mixing valve control would've been smoother, but I have no experience in this.


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## JohnDolz (Jan 16, 2016)

velvetfoot said:


> What is interesting to me are the spikes in flow temperature, like an on/off kind of thing with a differential.  I would've thought mixing valve control would've been smoother, but I have no experience in this.


I agree, I think Tom C had a thought on that (the type of device making the adjustment) - I will send him a note and ask him to weigh in. The other thought I have is that these systems are designed for a European environment. My understanding is that they do not have thermostats and cirulator pumps. Instead they have a pump (they call is a radiator pump) that pushes water through the whole loop (sometimes 2 loops in a bigger house but the Effecta can drive multiple shunt valves). The end result of this is that they have constant temp on the return water. In my environment I have circulators kicking on and off (plus the DHW spike) that change the temp of the return water. I have a big Modine Hydronic heater in my basement, when that thing kicks on it returns ice cubes into the return line. I'm thinking that this causes my controller to keep chasing ideal temps. I am open to other thoughts.

Tom what do you think?


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## velvetfoot (Jan 16, 2016)

What does the 40(41) mean?  It sort of implies a differential around a set point?


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## JohnDolz (Jan 16, 2016)

velvetfoot said:


> What does the 40(41) mean?  It sort of implies a differential around a set point?


The (41) is the target temp based on the outdoor temp. The 40 is the actual temp.


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## JohnDolz (Jan 16, 2016)

JohnDolz said:


> I agree, I think Tom C had a thought on that (the type of device making the adjustment) - I will send him a note and ask him to weigh in. The other thought I have is that these systems are designed for a European environment. My understanding is that they do not have thermostats and cirulator pumps. Instead they have a pump (they call is a radiator pump) that pushes water through the whole loop (sometimes 2 loops in a bigger house but the Effecta can drive multiple shunt valves). The end result of this is that they have constant temp on the return water. In my environment I have circulators kicking on and off (plus the DHW spike) that change the temp of the return water. I have a big Modine Hydronic heater in my basement, when that thing kicks on it returns ice cubes into the return line. I'm thinking that this causes my controller to keep chasing ideal temps. I am open to other thoughts.
> 
> Tom what do you think?


Just thinking about this and would like to take back my comments on the theory of circulator pumps. Since all my zones would be in constant call during recovery  the return temp should be pretty constant (trending up) so I imagine it is either how the motor works or how the programming was done. In theory my pumps should always be on but in reality that is not the case.


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## DBoon (Jan 16, 2016)

maple1 said:


> I changed my habits last year as I also read then observed first hand that lower temps = less wood burned. I don't do any mixing though, I just deplete my storage before I burn. Depleted = when the house can no longer maintain temp.



I've been following various threads in this topic and my main question has been whether John's system is just one result that could be obtained or if another, equivalent result could be obtained through the following:

1. Install TRVs on cast iron radiators that have sufficient size to heat at water temperatures in the 100-120 degree F range (120 degrees needed for a 0 degree outdoor day, 100 degrees ok for a 40 degree outdoor day)
2. Install a constant pressure pump to circulate water from boiler storage
3. Charge storage when water temps are ~100 degrees F up to ~180 degrees F

That seems to be Maple1's approach, and simpler with less control complexity and "things that can go wrong".  What am I missing?


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## JohnDolz (Jan 16, 2016)

DBoon said:


> I've been following various threads in this topic and my main question has been whether John's system is just one result that could be obtained or if another, equivalent result could be obtained through the following:
> 
> 1. Install TRVs on cast iron radiators that have sufficient size to heat at water temperatures in the 100-120 degree F range (120 degrees needed for a 0 degree outdoor day, 100 degrees ok for a 40 degree outdoor day)
> 2. Install a constant pressure pump to circulate water from boiler storage
> ...


If you are talking about not mixing water and just puling from the top of the tank I would refer back to the post I wrote referring to using "cruise control" in a car. You will loose the extra mileage you can get via mixing and being really stingy with your water. If what you are talking about is simply running temperature down in the storage, you might gain some efficiencies on the lower end but mainly I think you are just stretching time between firings.


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## DBoon (Jan 16, 2016)

Well, I'm not looking for analogies, I'm looking for some sort of technical detail.  But here is what I think you are advocating - If a TRV on a radiator in a room opens, and a constant pressure pump pumping from the top of the tank pushes water to the radiator until it gets warm enough to close the TRV valve, the downside is that it is not sensitive to outdoor temperatures - it might push too hot water to the radiator and overshoot the desired temperature a bit.  I think what you are advocating is an outdoor reset control, and the benefit of efficiency comes with the outdoor reset, and a mixing valve on the storage output is used in conjunction with an outdoor reset to ensure that the water temperature is only what is needed.  Is that correct?


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## JohnDolz (Jan 16, 2016)

DBoon said:


> Well, I'm not looking for analogies, I'm looking for some sort of technical detail.  But here is what I think you are advocating - If a TRV on a radiator in a room opens, and a constant pressure pump pumping from the top of the tank pushes water to the radiator until it gets warm enough to close the TRV valve, the downside is that it is not sensitive to outdoor temperatures - it might push too hot water to the radiator and overshoot the desired temperature a bit.  I think what you are advocating is an outdoor reset control, and the benefit of efficiency comes with the outdoor reset, and a mixing valve on the storage output is used in conjunction with an outdoor reset to ensure that the water temperature is only what is needed.  Is that correct?


Correct. I will leave it to the Engineers to validate the math/provide technical data (I did go to RPI but I played football and was a Management Major). I never did the math behind using cruise control but I trust when I am told that it results in better overall gas mileage. I can tell you from personal experience that I can heat for longer periods of time on the same amount of BTU's in my tanks.


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## JohnDolz (Jan 16, 2016)

DBoon said:


> Well, I'm not looking for analogies, I'm looking for some sort of technical detail.  But here is what I think you are advocating - If a TRV on a radiator in a room opens, and a constant pressure pump pumping from the top of the tank pushes water to the radiator until it gets warm enough to close the TRV valve, the downside is that it is not sensitive to outdoor temperatures - it might push too hot water to the radiator and overshoot the desired temperature a bit.  I think what you are advocating is an outdoor reset control, and the benefit of efficiency comes with the outdoor reset, and a mixing valve on the storage output is used in conjunction with an outdoor reset to ensure that the water temperature is only what is needed.  Is that correct?


Also as you are doing your research you can look into high efficiency condensing gas boilers. I learned that they get their high efficiency ratings when they are firing at very low temperatures. Mine is rated 95% Efficient and that # comes with 140F Supply and 120F Return (not sure if those are the temps that all boilers are tested/rated at). If I understood what I read correctly, condensing boilers will only condense (and therefore be really efficient) when return water is 120 or less. My propane boiler (Triangle Tube) is designed in Belgium, designed to use an Outdoor reset and follow a heat curve (you have the ability to move the endpoints around and then it is linear). I didn't know anything about this when it was installed (just followed my plumbers recommendation) and it was installed with a fixed firing point of 180 so it never actually condensed. Long story to be told over a coffee but again it is the same theory of efficiency gained at low temps. Hope this helps.


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## TCaldwell (Jan 16, 2016)

It was explained to me that, if baseboards flow is too low it will stratify in the pipe, causing cooler spots in the fin tube. This isn't the case with radiators as they will eventually homogenize in temp.
  in my humble opinion trv's with radiators with outdoor reset, with system running all the time would be hard to beat, you could have lower flows resulting in longer storage drawdown. However john's system is case in point for outdoor reset with indoor feedback, even with fin tube.
 I've looked for empirical data on odr, not able to find much other than not having to play thermostat catchup 20 or so times a day and matching load with demand only supplying what's needed. I guess it is possible this can add up!
  The temp spikes or oscillations around design water temp set point are a result of floating point control that is employed with most odr equipt manufacturers. This is not as stable as proportional control but widely used, the controller probably filters/averages these oscillations to arrive at a stable reading.
  A better approach than running the garn circ 24/7 would be to use the end switch from your zone box and tie it to a single zone relay box that will energize the garn circ whenever a zone calls


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## JohnDolz (Jan 16, 2016)

TCaldwell said:


> It was explained to me that, if baseboards flow is too low it will stratify in the pipe, causing cooler spots in the fin tube. This isn't the case with radiators as they will eventually homogenize in temp.
> in my humble opinion trv's with radiators with outdoor reset, with system running all the time would be hard to beat, you could have lower flows resulting in longer storage drawdown. However john's system is case in point for outdoor reset with indoor feedback, even with fin tube.
> I've looked for empirical data on odr, not able to find much other than not having to play thermostat catchup 20 or so times a day and matching load with demand only supplying what's needed. I guess it is possible this can add up!
> The temp spikes or oscillations around design water temp set point are a result of floating point control that is employed with most odr equipt manufacturers. This is not as stable as proportional control but widely used, the controller probably filters/averages these oscillations to arrive at a stable reading.
> A better approach than running the garn circ 24/7 would be to use the end switch from your zone box and tie it to a single zone relay box that will energize the garn circ whenever a zone calls


Thanks for the info Tom. Once again exposing my ignorance I had to go to Youtube to learn what TRV's are/do. After taking a look I would agree, running low temperature flow water that is then leveraged on a radiator by radiator basis would seem to get you everything you could get per BTU. One thought though is you could potentially drive yourself crazy trying to find the sweet spot between the TRV settings and the right heat curve. As far as stratification within the pipe, I've never noticed any cool spots but honestly never thought about it.


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## TCaldwell (Jan 16, 2016)

The low flow that can stratify for fin tube is anything much less than a gallon per minute, I believe you have taco 3 speeds, if they are comparable to a grundfos 15-58 3 sp, speed 1 i was getting 2 to 4.5 gpm per zone, no stratification worry there.


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## JohnDolz (Jan 16, 2016)

T


TCaldwell said:


> The low flow that can stratify for fin tube is anything much less than a gallon per minute, I believe you have taco 3 speeds, if they are comparable to a grundfos 15-58 3 sp, speed 1 i was getting 2 to 4.5 gpm per zone, no stratification worry there.


Thank you sir!


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## Woodfarmer1 (Jan 16, 2016)

My trv's are all the way open, as I need all the heat I can get out of them.


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## DBoon (Jan 17, 2016)

JohnDolz said:


> Correct.


Thanks for this confirmation - that is what I surmised.  Regarding the high efficiencies of condensing boilers, this is basically due to the capture of the latent heat in the flue gas as it condenses to liquid, and the low return temperatures are what makes this possible. Then, ODR with a mixing valve and flow control provides benefits in maintaining the storage tank thermocline, which I can easily buy into as well.  



TCaldwell said:


> trv's with radiators with outdoor reset, with system running all the time would be hard to beat, you could have lower flows resulting in longer storage drawdown.


That's pretty much my thoughts.  I'm lucky that I can design from the ground up and don't have to work with an existing system (i.e. fin-tube radiators), which would restrict my strategies somewhat and may require more complex control schemes. 



TCaldwell said:


> I've looked for empirical data on odr


Yeah, me too.  But I can believe that it can save money in some cases.  For instance, my cast iron radiator system has two zones, and one of the thermostats turns on at set temperature and off at set temperature +4 degrees.  If the temperature is warm, the cast iron radiators will take a while to heat up, and then once the temperature heat +4 degrees, and the boiler goes off, the room temperature will keep rising if the outdoor temperature is not too high.  ODR senses that and keeps the boiler water output temperature lower to prevent unnecessary overshoot and unnecessary heating.


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## JohnDolz (Jan 17, 2016)

DBoon said:


> Thanks for this confirmation - that is what I surmised.  Regarding the high efficiencies of condensing boilers, this is basically due to the capture of the latent heat in the flue gas as it condenses to liquid, and the low return temperatures are what makes this possible. Then, ODR with a mixing valve and flow control provides benefits in maintaining the storage tank thermocline, which I can easily buy into as well.
> 
> 
> That's pretty much my thoughts.  I'm lucky that I can design from the ground up and don't have to work with an existing system (i.e. fin-tube radiators), which would restrict my strategies somewhat and may require more complex control schemes.
> ...


You are both way beyond my knowledge level so I will leave the conversation to the 2 of you. In my case, when my propane boiler kicks in I have an electric valve that isolates my thermal storage and my the propane boiler just provides low temp water directly to the heating zones. The ODR in the propane boiler tells the propane boiler what the target is for the Supply water. I programmed it with basically the same heat curve that I use for my thermal storage which created a new challenge. Since my supply target was so close to the return temp I had the boiler cycling on and off almost every minute. It was mild outside so maybe I just need to pull the end points of my heat curve in for the hotter days. I adjusted the programming so that there is a minimum of 5 minutes between firings - the thought is this will cause return temp to drop. I haven't tested it now that it is colder, too lazy and too cheap to burn the propane.


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## velvetfoot (Jan 17, 2016)

JohnDolz said:


> I have an electric valve that isolates my thermal storage


Could you go into a little more detail?  eg, normally open, motor vs solenoid, make/model, etc?  

I do  understand you are indeed getting max efficiency by operating your mod/con boiler in the condensing zone.  It does modulate, right?


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## JohnDolz (Jan 17, 2016)

DBoon said:


> Thanks for this confirmation - that is what I surmised.  Regarding the high efficiencies of condensing boilers, this is basically due to the capture of the latent heat in the flue gas as it condenses to liquid, and the low return temperatures are what makes this possible. Then, ODR with a mixing valve and flow control provides benefits in maintaining the storage tank thermocline, which I can easily buy into as well.
> 
> 
> That's pretty much my thoughts.  I'm lucky that I can design from the ground up and don't have to work with an existing system (i.e. fin-tube radiators), which would restrict my strategies somewhat and may require more complex control schemes.
> ...


You are both way beyond my knowledge level so I will leave the conversation to the 2 of you. In my case, when my propane boiler kicks in I have an electric valve that isolates my thermal storage and my the propane boiler just provides low temp water directly to the heating zones. The ODR in the propane boiler tells the propane boiler what the target is for the Supply water. I programmed it with basically the same heat curve that I use for my thermal storage which created a new challenge. Since my supply target was so close to the return temp I had the boiler cycling on and off almost every minute. It was mild outside so maybe I just need to pull the end points of my heat curve in for the hotter days. I adjusted the programming so that there is a minimum of 5 minutes between firings - the thought is this will cause return temp to drop. I haven't tested it now that it is colder, too lazy and too cheap to burn the propane.


velvetfoot said:


> Could you go into a little more detail?  eg, normally open, motor vs solenoid, make/model, etc?
> 
> I do  understand you are indeed getting max efficiency by operating your mod/con boiler in the condensing zone.  It does modulate, right?


Yes, it modulates. The valve is normally open. I will take some pics later tonight, I don't know much about it - last year I was enjoying someone else doing it all for me. This year I have been forced into the drivers seat. The reason I have it is because I was getting supply water from the propane boiler feeding into my tanks through the return line. Based on what I have been reading it probably should have been engineered a little different. I may need to quit this forum before I rip everything out, baseboard emitters included, and start from scratch.


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## JohnDolz (Jan 18, 2016)

velvetfoot said:


> Could you go into a little more detail?  eg, normally open, motor vs solenoid, make/model, etc?
> 
> I do  understand you are indeed getting max efficiency by operating your mod/con boiler in the condensing zone.  It does modulate, right?


See photos, hope they help.


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## TCaldwell (Jan 18, 2016)

JohnDolz said:


> You are both way beyond my knowledge level so I will leave the conversation to the 2 of you. In my case, when my propane boiler kicks in I have an electric valve that isolates my thermal storage and my the propane boiler just provides low temp water directly to the heating zones. The ODR in the propane boiler tells the propane boiler what the target is for the Supply water. I programmed it with basically the same heat curve that I use for my thermal storage which created a new challenge. Since my supply target was so close to the return temp I had the boiler cycling on and off almost every minute. It was mild outside so maybe I just need to pull the end points of my heat curve in for the hotter days. I adjusted the programming so that there is a minimum of 5 minutes between firings - the thought is this will cause return temp to drop. I haven't tested it now that it is colder, too lazy and too cheap to burn the propane.
> 
> Yes, it modulates. The valve is normally open. I will take some pics later tonight, I don't know much about it - last year I was enjoying someone else doing it all for me. This year I have been forced into the drivers seat. The reason I have it is because I was getting supply water from the propane boiler feeding into my tanks through the return line. Based on what I have been reading it probably should have been engineered a little different. I may need to quit this forum before I rip everything out, baseboard emitters included, and start from scratch.


Has the drawn line move already?


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## JohnDolz (Jan 18, 2016)

TCaldwell said:


> Has the drawn line move already?


In studying my past behavior I find that I need to complete the things on my list before I move the line. For now I have been educated on the need for air intake and then I have some plumbing that needs to be done. Luckily I lined up an expert technician so I expect these items to be knocked out in no time.


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## cpeltier (Jan 18, 2016)

Woodfarmer1 said:


> I built a timber frame with sip panels and it should be sealed up tighter than a popcorn fart, but when the wind howls it seems to come right through the walls, all my big windows probably don't help either



I built an almost net-zero house half way up a 4000' mountain in Vermont and just returned so I'm late to this thread. My mountain house is also built with SIP panels, ICF foundation, and Marvin Integrity (good but not high end) windows. My house is very tight and it's 100% radiant, no baseboard or fan coil. This house uses a 1st generation NoFossil control system as a starting point. I completely rewrote it for my use (added One Wire sensors and PWM/PID for Zone control) and it works well but is a totally custom one-off system (which I don't like). It's a standing column GeoThermal Water-to-water heat pump with a backup or stage 2 ModCon LP boiler. My design temperature using Outdoor reset is 115F @ -25F. My SIP panels were foamed at the joints and the house is very tight. So tight in fact that if I turn on my kitchen fan it will suck the fire out of the fireplace. I walked around the house with a FLIR and fixed many gaps. I still have a few outstanding which the Cluster flies have found.
http://mirabal.netcarrier.com:84/cgi-bin/statuscgi


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## JohnDolz (Jan 18, 2016)

cpeltier said:


> I built an almost net-zero house half way up a 4000' mountain in Vermont and just returned so I'm late to this thread. My mountain house is also built with SIP panels, ICF foundation, and Marvin Integrity (good but not high end) windows. My house is very tight and it's 100% radiant, no baseboard or fan coil. This house uses a 1st generation NoFossil control system as a starting point. I completely rewrote it for my use (added One Wire sensors and PWM/PID for Zone control) and it works well but is a totally custom one-off system (which I don't like). It's a standing column GeoThermal Water-to-water heat pump with a backup or stage 2 ModCon LP boiler. My design temperature using Outdoor reset is 115F @ -25F. My SIP panels were foamed at the joints and the house is very tight. So tight in fact that if I turn on my kitchen fan it will suck the fire out of the fireplace. I walked around the house with a FLIR and fixed many gaps. I still have a few outstanding which the Cluster flies have found.
> http://mirabal.netcarrier.com:84/cgi-bin/statuscgi


Funny about a million years ago I interviewed with a company that (if I recall correctly) had the patent on closed loop Geothermal, still surprised that it never took off as a concept. Question for you on your LP boiler, with the design temp so low do you have any issues with it firing on and off? I mentioned it somewhere in this thread but when I tried that I had my boiler firing on and off almost every minute because the return temp was so close to Design temp. That was a fairly warm day. Since then I also adjusted the programming in the boiler so it has a minimum of 5 minutes between firings. I've been too lazy to test it again to see if this creates more of a constant firing at low temp. Have you seen this issue? If so how did you address it? Thanks.


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## cpeltier (Jan 18, 2016)

JohnDolz said:


> Funny about a million years ago I interviewed with a company that (if I recall correctly) had the patent on closed loop Geothermal, still surprised that it never took off as a concept. Question for you on your LP boiler, with the design temp so low do you have any issues with it firing on and off? I mentioned it somewhere in this thread but when I tried that I had my boiler firing on and off almost every minute because the return temp was so close to Design temp. That was a fairly warm day. Since then I also adjusted the programming in the boiler so it has a minimum of 5 minutes between firings. I've been too lazy to test it again to see if this creates more of a constant firing at low temp. Have you seen this issue? If so how did you address it? Thanks.



This system went live in 2009/2010 season so I had to deal with technology available at that time. My ModCon did not have Modbus control and I didn't want to have to directly control the modulation rate of the boiler as I had a fault tolerant backup mode that took my fancy control system out of the equation if a fault was detected (unoccupied home in a harsh environment). I programmed the LP ModCon (Triangle tube, 4-1 turndown ratio) with an ODR curve that matches my control system. My control system would generate a boiler demand if the heat pump could not keep up but it was very stingy in its operation as it's primarily a solar powered (grid tied) house. I had the zones split up into 4 groups and each group would synchronize on a time interval with a PWM cycle designed to minimize overlap as I was pushing the limits of a 5 ton heat pump on a 3500 square foot structure in that environment. There are no thermostats, just OneWire sensors embedded in the drywall in each zone. The control system would adjust the target water temperatures based on the hottest desired room temperature. The PWM mechanism would take care of the rest. The system or LP boiler doesn't short cycle. It works very well. The key to my system is in the programming of the control system; PWM for zone control, and having the thermostats embedded in the control system so I know what the desired room temperature is allowing me to run the coldest system water temperatures possible. Running the coldest water possible is key to getting the highest system efficiency and becomes paramount when using a Heat Pump as your hot water source. The heat pump won't generate water hotter then 115F anyway and it's COP is also very poor at this limit. I designed my radiant heating system based on this fact and all of the loops were sized according to this low design temperature.


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## JohnDolz (Jan 18, 2016)

cpeltier said:


> This system went live in 2009/2010 season so I had to deal with technology available at that time. My ModCon did not have Modbus control and I didn't want to have to directly control the modulation rate of the boiler as I had a fault tolerant backup mode that took my fancy control system out of the equation if a fault was detected (unoccupied home in a harsh environment). I programmed the LP ModCon (Triangle tube, 4-1 turndown ratio) with an ODR curve that matches my control system. My control system would generate a boiler demand if the heat pump could not keep up but it was very stingy in its operation as it's primarily a solar powered (grid tied) house. I had the zones split up into 4 groups and each group would synchronize on a time interval with a PWM cycle designed to minimize overlap as I was pushing the limits of a 5 ton heat pump on a 3500 square foot structure in that environment. There are no thermostats, just OneWire sensors embedded in the drywall in each zone. The control system would adjust the target water temperatures based on the hottest desired room temperature. The PWM mechanism would take care of the rest. The system or LP boiler doesn't short cycle. It works very well. The key to my system is in the programming of the control system; PWM for zone control, and having the thermostats embedded in the control system so I know what the desired room temperature is allowing me to run the coldest system water temperatures possible. Running the coldest water possible is key to getting the highest system efficiency and becomes paramount when using a Heat Pump as your hot water source. The heat pump won't generate water hotter then 115F anyway and it's COP is also very poor at this limit. I designed my radiant heating system based on this fact and all of the loops were sized according to this low design temperature.


Thanks, I have a Triangle Tube, installed around 2011. I believe mine was the first generation with the ODR tied into he heatcurve. I say this because this year I finally learned a few things about it, including the fact that it  was reading the wrong outdoor temp. In exploring this I learned I had he 1st generation software/display module. They sent me an updated one which I installed a few weeks ago. How did you avoid the short cycle? or is it simply the fact that it is so cold up there that return temp differential is always great enough to avoid this (spent many years skiing at Killington so I understand it is a bit chillier than here in CT).


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## cpeltier (Jan 18, 2016)

JohnDolz said:


> Thanks, I have a Triangle Tube, installed around 2011. I believe mine was the first generation with the ODR tied into he heatcurve. I say this because this year I finally learned a few things about it, including the fact that it  was reading the wrong outdoor temp. In exploring this I learned I had he 1st generation software/display module. They sent me an updated one which I installed a few weeks ago. How did you avoid the short cycle? or is it simply the fact that it is so cold up there that return temp differential is always great enough to avoid this (spent many years skiing at Killington so I understand it is a bit chillier than here in CT).


Mine is the Triangle Tube Prestige 175 KBTU with the Honeywell MCBA control module. It will short cycle if the load is less then it's maximum turn-down. For me it's around 35 KBTU/hr Input when that happens. I haven't really noticed it as the second stage almost never runs except when it's generating DHW. It's a ski house on Lincoln Peak at Sugarbush. The DHW is on the ModCon because when the 10 people come back from skiing they all take a shower at once! I do have a desuper coil in the DHW tank which does the initial heat up and keeps it topped off. I'd like to know more about this updated MCBA module!


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## JohnDolz (Jan 18, 2016)

cpeltier said:


> Mine is the Triangle Tube Prestige 175 KBTU with the Honeywell MCBA control module. It will short cycle if the load is less then it's maximum turn-down. For me it's around 35 KBTU/hr Input when that happens. I haven't really noticed it as the second stage almost never runs except when it's generating DHW. It's a ski house on Lincoln Peak at Sugarbush. The DHW is on the ModCon because when the 10 people come back from skiing they all take a shower at once! I do have a desuper coil in the DHW tank which does the initial heat up and keeps it topped off. I'd like to know more about this updated MCBA module!


Can I bribe you to stop by on your way to Sugarbush? You can have the best Cappuccino you have ever had. Not quite sure what Control Module I have. I know when I asked about adjusting the outdoor temp (I was talking to the engineer at Triangle) he asked me what version software it was, from there he determined I was on the old version and sent me out a new module to install. The outdoor temp then matched what I was getting on my Effecta ODR. Their warranty department is supposed to handle this, if you give them a call I am sure they can walk you through it. Just for more laughs my plumber installed the ODR on the east side of my house under the boiler exhaust. Want to guess how well things worked when it was set to ODR mode? You can message me as well, happy to give you my phone # and check anything you like. I am heading out of town tomorrow early AM so this is a tough week.


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## JohnDolz (Jan 18, 2016)

cpeltier said:


> Mine is the Triangle Tube Prestige 175 KBTU with the Honeywell MCBA control module. It will short cycle if the load is less then it's maximum turn-down. For me it's around 35 KBTU/hr Input when that happens. I haven't really noticed it as the second stage almost never runs except when it's generating DHW. It's a ski house on Lincoln Peak at Sugarbush. The DHW is on the ModCon because when the 10 people come back from skiing they all take a shower at once! I do have a desuper coil in the DHW tank which does the initial heat up and keeps it topped off. I'd like to know more about this updated MCBA module!


Since you get me thinking and since I am leaving for the week I thought I would test my backup system. I find that even with it being reasonably cold today and windy I think I may have a challenge with short cycle (not sure what a good time between cycles really is, any idea?). The design temp is 114 today, when I run my thermal storage system my design and return temps are almost identical. I turned of the thermal to test the propane and of course the firing shut down almost instant (CH Demand temp met). Since I programmed the minimum time between firing to 5 minutes my circulators ran for a while dropping the return temp. Next time my boiler fired it fired for at least a few minutes before the return temp climbed enough that CH Demand Temp was met. I have a Modine Hydronic heater that is running in the basement, I know that returns really cold water - point is that if I had that shut off (which I prefer due to the noise) I would bet my return temps would return to supply temp very quickly. Wondering how you get around this? Maybe the answer is just knowing what an acceptable # of cycles per day is. I am going to let this run for an hour or wo and see if I maintain hose temps or not. Any insight is appreciated!


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## TCaldwell (Jan 18, 2016)

John,
  Possibly Cpeltier's radiant return temps are low enough for a sustained time allowing his boiler not to cycle? I think with fin tube or any other low mass emitter running properly on odr(as yours does), pretty much constant flow with tight supply and return delta would induce cycling. Can you limit the firing rate of the boiler? I dunno


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## JohnDolz (Jan 18, 2016)

TCaldwell said:


> John,
> Possibly Cpeltier's radiant return temps are low enough for a sustained time allowing his boiler not to cycle? I think with fin tube or any other low mass emitter running properly on odr(as yours does), pretty much constant flow with tight supply and return delta would induce cycling. Can you limit the firing rate of the boiler? I dunno


Thanks. I do have the ability to control the minimum time between firings. I sent Triangle Tube an email earlier today asking what target I should be shooting for, hard to hit the bulls-eye if you don't know where it is or what it looks like. I haven't paid any attention to it as I really haven't used it since I fired up the wood boiler but I am going away this week and with it being so cold I thought I better make sure my backup system would actually do something. It seems to work fine and kept me at a cozy 72. The question is around the # of firings and whether or not I am cutting into the longevity of the boiler.


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## Boardroom (Jan 18, 2016)

DBoon said:


> I've been following various threads in this topic and my main question has been whether John's system is just one result that could be obtained or if another, equivalent result could be obtained through the following:
> 
> 1. Install TRVs on cast iron radiators that have sufficient size to heat at water temperatures in the 100-120 degree F range (120 degrees needed for a 0 degree outdoor day, 100 degrees ok for a 40 degree outdoor day)
> 2. Install a constant pressure pump to circulate water from boiler storage
> ...



OK. I have been following this thread and must admit John that I am guilty as you were of thinking that I need very hot water to heat my house. There is no way that my drafty late 1800's farm house could be heated on anything less, but I am willing to consider it.
I have the 3 things DBoon is talking about - cast iron rads with TRV's and an Alpha pump. I Charge my tanks as described above and draw directly from the top of the tanks.
I already have a mixing valve sitting here so thought I might as well give it a try.  I just have one concern. If I put the mixing valve before the Alpha so that the Alpha pulls through the MV, does this affect the operation of the Alpha?  I don't think so but thought I should ask. Thanks.


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## JohnDolz (Jan 18, 2016)

Boardroom said:


> OK. I have been following this thread and must admit John that I am guilty as you were of thinking that I need very hot water to heat my house. There is no way that my drafty late 1800's farm house could be heated on anything less, but I am willing to consider it.
> I have the 3 things DBoon is talking about - cast iron rads with TRV's and an Alpha pump. I Charge my tanks as described above and draw directly from the top of the tanks.
> I already have a mixing valve sitting here so thought I might as well give it a try.  I just have one concern. If I put the mixing valve before the Alpha so that the Alpha pulls through the MV, does this affect the operation of the Alpha?  I don't think so but thought I should ask. Thanks.


Nice I look forward to reading about your results. I can't imagine it will impact your alpha pump but will leave it to others to comment. I'm assuming you are testing with a manual mixing valve (vs something tied to a controller and ODR) so keep in mind that the Design temp changes as outside temp changes. You will also need to find what temp works for your house. Tonight for example, it is -6C out and the Design temp for me is 43C, keeps me at about 22C. When you test this I suggest you try maintaining a temp vs. heating up to certain temp, as mentioned recovery is a bear at low temps.


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## cpeltier (Jan 19, 2016)

JohnDolz said:


> Since you get me thinking and since I am leaving for the week I thought I would test my backup system. I find that even with it being reasonably cold today and windy I think I may have a challenge with short cycle (not sure what a good time between cycles really is, any idea?). The design temp is 114 today, when I run my thermal storage system my design and return temps are almost identical. I turned of the thermal to test the propane and of course the firing shut down almost instant (CH Demand temp met). Since I programmed the minimum time between firing to 5 minutes my circulators ran for a while dropping the return temp. Next time my boiler fired it fired for at least a few minutes before the return temp climbed enough that CH Demand Temp was met. I have a Modine Hydronic heater that is running in the basement, I know that returns really cold water - point is that if I had that shut off (which I prefer due to the noise) I would bet my return temps would return to supply temp very quickly. Wondering how you get around this? Maybe the answer is just knowing what an acceptable # of cycles per day is. I am going to let this run for an hour or wo and see if I maintain hose temps or not. Any insight is appreciated!


I did engineer my radiant loops carefully and I'm getting at least a ten degree delta across them. I even using a fixed speed pump (was a delta T pump now optioned for fixed speed because it never worked right and if you engineer it right you don't need a delta T mode). The flow rate on the smaller zones can get high since I'm using a single pump with zone valves and I have plans on replacing that with an Alpha in delta P mode to keep the delta T dead on across all loops all the time. 

To answer your question generally I have a healthy 10 degree difference between supply and return although the flow rates can be quite variable - anywhere from 1.5 GPM to 11 GPM. Looking at the math on this I would expect my small zones to short cycle the LP boiler if run by themselves. My system does synchronize their operation with other zones so as to provide enough of a load (but not too much for the heat pump) to operate.


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## cpeltier (Jan 19, 2016)

Boardroom said:


> OK. I have been following this thread and must admit John that I am guilty as you were of thinking that I need very hot water to heat my house. There is no way that my drafty late 1800's farm house could be heated on anything less, but I am willing to consider it.
> I have the 3 things DBoon is talking about - cast iron rads with TRV's and an Alpha pump. I Charge my tanks as described above and draw directly from the top of the tanks.
> I already have a mixing valve sitting here so thought I might as well give it a try.  I just have one concern. If I put the mixing valve before the Alpha so that the Alpha pulls through the MV, does this affect the operation of the Alpha?  I don't think so but thought I should ask. Thanks.



It probably would be ok but it's always better to push through a pressure drop or restriction and pump away from your expansion tank which is the most important rule!


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## Kristen (Jan 19, 2016)

cpeltier said:


> There are no thermostats, just OneWire sensors embedded in the drywall in each zone



I would love to do that ... just have 1-wire temperature sensors in the rooms - both for historical data logging and something else to then control the valves etc. Everything I see has either thermostats or temperature sensors that are, to my thinking, "expensive".

I have used some 1-wire temperature sensors in the past, for a monitoring project, and I had to make up small circuit boards for each sensor (can;t even remember what components were needed now - but it wasn't much).

Did you have to do similar? or were you able to just wire the 1-wire sensors direct back to the control unit, and handle the requirements there?


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## cpeltier (Jan 19, 2016)

Kristen said:


> I would love to do that ... just have 1-wire temperature sensors in the rooms - both for historical data logging and something else to then control the valves etc. Everything I see has either thermostats or temperature sensors that are, to my thinking, "expensive".
> 
> I have used some 1-wire temperature sensors in the past, for a monitoring project, and I had to make up small circuit boards for each sensor (can;t even remember what components were needed now - but it wasn't much).
> 
> Did you have to do similar? or were you able to just wire the 1-wire sensors direct back to the control unit, and handle the requirements there?



For that project (Vermont ski house) I used this on a Linux based system (TS-7800):
http://www.ibuttonlink.com/products/linkusbi
I also used a DS2409 based 1 wire hub that connected to above so that I could run twisted pair in different directions (Star topology) to daisy chain sensors.

My latest project (Home in PA) uses Modbus based OneWire controllers on the EasyIO which make it really simple. Examples of this are:
https://www.embeddedarm.com/products/board-detail.php?product=TS-1700
http://www.barix.com/products/barionet-family/barix/Product/show/barix-x8/  (about $70)

You can't daisy chain with these. Home runs per sensor but then you don't have to worry about knowing the address of the sensor either.

Modbus is great but it does require a controller with a Modbus master or a USB based interface for a PC or Linux based SBC.


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## JohnDolz (Jan 19, 2016)

cpeltier said:


> I did engineer my radiant loops carefully and I'm getting at least a ten degree delta across them. I even using a fixed speed pump (was a delta T pump now optioned for fixed speed because it never worked right and if you engineer it right you don't need a delta T mode). The flow rate on the smaller zones can get high since I'm using a single pump with zone valves and I have plans on replacing that with an Alpha in delta P mode to keep the delta T dead on across all loops all the time.
> 
> To answer your question generally I have a healthy 10 degree difference between supply and return although the flow rates can be quite variable - anywhere from 1.5 GPM to 11 GPM. Looking at the math on this I would expect my small zones to short cycle the LP boiler if run by themselves. My system does synchronize their operation with other zones so as to provide enough of a load (but not too much for the heat pump) to operate.


Thanks for the info. I have all my pumps set to their lowest speeds and have almost constant call from all zones (except my Modine Heater - I keep that zone a bit lower as it is the basement and I prefer not to hear the noise). I have an email out to Triangle Tube to get an understanding of what ideal firing length and time between firings. For now I am controlling it with the "minimum time between firings", currently set at 5 minutes per their previous recommendation. That recommendation was made to see what we got so I'm curious to hear back. At some point I may look at the overall engineering but since I rarely ever use it it doesn't make much sense unless it improves what I have doing with the wood boiler.


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## Boardroom (Jan 19, 2016)

cpeltier said:


> It probably would be ok but it's always better to push through a pressure drop or restriction and pump away from your expansion tank which is the most important rule!



My concern with putting the Alpha in front of the MV or restriction is that the Alpha would not feel a pressure drop from the load and would not know when to pump. If I put it after the MV it will feel the loss in pressure when a TRV opens. Sound right?


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## cpeltier (Jan 19, 2016)

Is it a three port mixing valve? Your correct that pumping away would be correct. If it's a single pipe loop with TRVs on mono-flow Ts I don't think delta P mode would do much since the system head barely changes. If it's a two pipe setup then it may work better.


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## JohnDolz (Jan 19, 2016)

cpeltier said:


> Is it a three port mixing valve? Your correct that pumping away would be correct. If it's a single pipe loop with TRVs on mono-flow Ts I don't think delta P mode would do much since the system head barely changes. If it's a two pipe setup then it may work better.


As you can tell I have no engineering knowledge (or knowledge of he alpha). I can only share that it was recommended that the pump be nfront (or after) the mixing valve so that it is pulling the water through vs. pushing. I understand your discussion is at a much more sophisticated level so I will observe, see what I learn and see if I end up replumbing my whole house.


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## Boardroom (Jan 19, 2016)

I would think it would be a simple setup as in the attached sketch. Yes John - I would just be experimenting with it manually for now.
I have only used the " Auto" setting on the Alpha. Would another setting be better? I guess I could read the manual someday.


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## JohnDolz (Jan 19, 2016)

Boardroom said:


> I would think it would be a simple setup as in the attached sketch. Yes John - I would just be experimenting with it manually for now.
> I have only used the " Auto" setting on the Alpha. Would another setting be better? I guess I could read the manual someday.


That is pretty much what I have, pulling from the tank vs the boiler.


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## JohnDolz (Jan 23, 2016)

Just thought I would put the above in context via wood usage. I just got back from a 4 day business trip so I got to see exactly how much wood my wife used. The last fire I started was Monday night, my wife did all the burning Tuesday - Fri night, I started a fire this AM. I have 2 4x4 racks in the basement and she used about 1.5 racks worth with at least 25% being pine. This was the coldest week we have had this year, in the teens every night and I do not believe it ever got out of the 20's during the day. Curious how this compares to others usage (understanding it depends on sq ft, how hot you keep the house, etc.).

Tom C - I know you log your wood usage, what are your thoughts?

Somewhere, maybe a different thread, we talked about the value of dry wood and the problems associated with bridging. Last year was a moist wood, bridging nightmare, Went on the same trip last year and my wife burned 2x the wood. I attribute most of the difference in the wet wood and bridging that came from it but am please at how little wood was needed.


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## maple1 (Jan 23, 2016)

How long is your wood?

I measured the useable space in my firebox a couple years ago & came up with 3 cu.ft.. I don't use all that space, as it is about 22" deep and I aim to cut my wood at 18". Some rough figuring on 2 loads a day comes up with about 5 cu.ft./day for this time of year. Give or take, ballpark like.

(It was -18c here when I got up this morning - but calm & clear, thankfully. Should be good solar gain today once the sun gets up, going out later & wont be back to light up until 7pm or so maybe...)


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## JohnDolz (Jan 23, 2016)

maple1 said:


> How long is your wood?
> 
> I measured the useable space in my firebox a couple years ago & came up with 3 cu.ft.. I don't use all that space, as it is about 22" deep and I aim to cut my wood at 18". Some rough figuring on 2 loads a day comes up with about 5 cu.ft./day for this time of year. Give or take, ballpark like.
> 
> (It was -18c here when I got up this morning - but calm & clear, thankfully. Should be good solar gain today once the sun gets up, going out later & wont be back to light up until 7pm or so maybe...)


I shoot for 18" when I cut it but I get a lot of precut stuff. I would guess average of 15" this year.

If my memory is working my firebox holds 195 liters (from the specs). If I had to guess I would say a load usually is only 80% of this.


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## velvetfoot (Jan 23, 2016)

How wide are your fire boxes ?


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## Armaton (Jan 23, 2016)

John,

Do you get any significant heat from your Modine when your input water temps are low?


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## JohnDolz (Jan 23, 2016)

Armaton said:


> John,
> 
> Do you get any significant heat from your Modine when your input water temps are low?[/QUOTE
> I do but to be honest the noise is a bit annoying. I dropped my basement temp to 65 (from 67) just so it will not run as much. I have an office sedition that is WAY underpowered with a toe heater (unheatwd garage under it and basically 4 exposed walls). If I turn it to high that little thing will recover the room to 70 and then low will pretty much maintain it. Low temp emitter or minus plot in that rooms future (AV in the summer is a challenge).


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## maple1 (Jan 23, 2016)

JohnDolz said:


> I shoot for 18" when I cut it but I get a lot of precut stuff. I would guess average of 15" this year.
> 
> If my memory is working my firebox holds 195 liters (from the specs). If I had to guess I would say a load usually is only 80% of this.


 
So using 4x4, x1.5, x16", over 4 days, I come up with 8 cu.ft. per day?

(Roughly speaking...)


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## JohnDolz (Jan 23, 2016)

velvetfoot said:


> How wide are your fire boxes ?


I will measure it this evening, was out your way skiing at Butternut.


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## JohnDolz (Jan 23, 2016)

maple1 said:


> So using 4x4, x1.5, x16", over 4 days, I come up with 8 cu.ft. per day?
> 
> (Roughly speaking...)


Sounds reasonable but I have nothing to compare it to - is that good, bad, normal? I know it is a lot better than last year 


maple1 said:


> How long is your wood?
> 
> I measured the useable space in my firebox a couple years ago & came up with 3 cu.ft.. I don't use all that space, as it is about 22" deep and I aim to cut my wood at 18". Some rough figuring on 2 loads a day comes up with about 5 cu.ft./day for this time of year. Give or take, ballpark like.
> 
> (It was -18c here when I got up this morning - but calm & clear, thankfully. Should be good solar gain today once the sun gets up, going out later & wont be back to light up until 7pm or so maybe...)


Yu probably mentioned it before, how many sqft are you heating and what temp do you heat the house to? Just trying to get something to compare, understanding that it is impossible to get apples to apples.


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## maple1 (Jan 23, 2016)

20 year old 2700 sq.ft on 2 storeys, over 1500 sq.ft. of unfinished unheated basement. On an open hilltop. It doesn't do bad but there's room for improvement. Our siding is starting to look a little dated, if that ever gets redone there will be a layer of foam board under the new stuff. Really notice a heatload difference when its windy out.

I setback 3°c during the day in zones that aren't being used. And overnight also I guess on the opposite zones. Otherwise stats are at 20c, except for living room zone that is set at 22c in the evenings when everyone is in it and just sitting still. If its extra cold out, I'll set the others up 1 degree higher while I'm burning, sort of acts like having more storage. Aside from running storage as low as I can, I think timing burns with max heat demand helps too. So I am doing the bulk of my setback recovery late afternoon, just about the same time as my boiler is getting a good head of steam up.


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## JohnDolz (Jan 23, 2016)

maple1 said:


> 20 year old 2700 sq.ft on 2 storeys, over 1500 sq.ft. of unfinished unheated basement. On an open hilltop. It doesn't do bad but there's room for improvement. Our siding is starting to look a little dated, if that ever gets redone there will be a layer of foam board under the new stuff. Really notice a heatload difference when its windy out.
> 
> I setback 3°c during the day in zones that aren't being used. And overnight also I guess on the opposite zones. Otherwise stats are at 20c, except for living room zone that is set at 22c in the evenings when everyone is in it and just sitting still. If its extra cold out, I'll set the others up 1 degree higher while I'm burning, sort of acts like having more storage. Aside from running storage as low as I can, I think timing burns with max heat demand helps too. So I am doing the bulk of my setback recovery late afternoon, just about the same time as my boiler is getting a good head of steam up.


Thanks for the info, there are a million variables but having an idea of what others are doing helps create some type of Benchmark.


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## JohnDolz (Jan 23, 2016)

velvetfoot said:


> How wide are your fire boxes ?


19" wide (Tapers but not sure of width at bottom) 25" high, 22" deep


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## maple1 (Jan 23, 2016)

That's about 6 cu.ft. if I did my math right. Or twice the volume of what I measured mine to be. I think I'll double check my measurements when I clean tomorrow.


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## JohnDolz (Jan 23, 2016)

maple1 said:


> That's about 6 cu.ft. if I did my math right. Or twice the volume of what I measured mine to be. I think I'll double check my measurements when I clean tomorrow.


It is actually 195 liters (per the literature), using an online conversion tool that = 6.88 cuft.  Thinking about the guesstimate on 8 cuft per day (on avg) with approx 75 - 80% loaded - works out to about 6 fires. This sounds about right based on when I think my wife started fires over the last 4 days. We fill the firebox as much as we can but based on reality. shorter pieces of  wood, space between wood, etc. 75 - 80% sounds about right to me.


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## Armaton (Jan 24, 2016)

Wonder if using a mixing valve at the storage and mixing to the minimum temperature needed for your emitters would also extend storage useability for individuals that have a WTAX in their Forced air furnace? Should aid in stratification, even if they use a P/S, since they would be using a lot of the returned water to maintain the minimum temp.


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## JohnDolz (Jan 24, 2016)

Armaton said:


> Wonder if using a mixing valve at the storage and mixing to the minimum temperature needed for your emitters would also extend storage useability for individuals that have a WTAX in their Forced air furnace? Should aid in stratification, even if they use a P/S, since they would be using a lot of the returned water to maintain the minimum temp.


If I understand the question correctly i would think so. As mentioned, I have a Modine Hydronic Heater and one of those toe/kick heater which I believe I are simply WTAX's. They work fine for me, the blower is no much more often though - and would give the same benefit. My toe heater runs off of an aquastat so even with a low temp aquastat it will not come on in the shoulder seasons because the water temp is so low. I may require it at some point so the blower turns on whenever there is a call for heat and skip the aquastat (same as the Modine).


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## JohnDolz (Jan 28, 2016)

cpeltier said:


> Mine is the Triangle Tube Prestige 175 KBTU with the Honeywell MCBA control module. It will short cycle if the load is less then it's maximum turn-down. For me it's around 35 KBTU/hr Input when that happens. I haven't really noticed it as the second stage almost never runs except when it's generating DHW. It's a ski house on Lincoln Peak at Sugarbush. The DHW is on the ModCon because when the 10 people come back from skiing they all take a shower at once! I do have a desuper coil in the DHW tank which does the initial heat up and keeps it topped off. I'd like to know more about this updated MCBA module!


Thought you might be interested, I spoke to Triangle Tube yesterday and they informed me they tell people to shoot for 4 firing cycles per hour but they can live with anything under 10. There is no way to control the DeltaT so the only way to impact this is by playing with the minimum time between firing which will force a greater deltaT. The guy I spoke with was pretty knowledgeable and had a good suggestion of using the Triangle Tube to heat storage to a relatively low set point. I have an electric cutoff valve the cuts out my storage when the propane boiler fires. I can easily disengage this but I would then need to give the plumbing some thought as well as the setpoint controller which switches wood/propane heat sources according to tank temp. This would allow me to potentially get firing cycles to something like a few times per day or less. Since I rarely use propane to heat the house I will probably just stick with spreading the minimum time per fires but it is good to know should I ever tire of heating with wood and go back to propane.


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## maple1 (Jan 28, 2016)

I'm kind of in the dark to your scheming (lol), but I had my system plumbed & controlled so that when backup heat (electric boiler) was being used, it would only heat the distribution - it would not pull storage water. Did that with check valves. That created some pretty frequent short cycling. So this summer I pulled the check flapper out of one of my check valves & drilled a 1/4" hole in it, so that when the backup circ is running, it pulls a bit of water from bottom of storage through that 1/4" hole. That really smoothed out the electric boiler & reduced the short cycling. Of course, that means I'm paying for some kwh to heat a little bit of my storage, but I don't think it amounted to much. After a couple of days away from home over the holidays, my storage had still cooled off some, so it seemed it wasn't sending as much heat to storage as the stand by heat it was losing.


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## JohnDolz (Jan 28, 2016)

maple1 said:


> I'm kind of in the dark to your scheming (lol), but I had my system plumbed & controlled so that when backup heat (electric boiler) was being used, it would only heat the distribution - it would not pull storage water. Did that with check valves. That created some pretty frequent short cycling. So this summer I pulled the check flapper out of one of my check valves & drilled a 1/4" hole in it, so that when the backup circ is running, it pulls a bit of water from bottom of storage through that 1/4" hole. That really smoothed out the electric boiler & reduced the short cycling. Of course, that means I'm paying for some kwh to heat a little bit of my storage, but I don't think it amounted to much. After a couple of days away from home over the holidays, my storage had still cooled off some, so it seemed it wasn't sending as much heat to storage as the stand by heat it was losing.


I have a modulating/condensing boiler so what they would love to see is it run at its lowest modulation for the longest period of time. So their recommendation (ideally) is to heat the tank with very low temp water (controlled by the outdoor reset) which would cause a very long low temp burn followed by a very long period pulling off of the thermal storage. My propane boiler was originally set up incorrectly plus I was heating with high temp water so, like you, I put in a check valve. One day I may revisit this for the fun of it but since I can control the short cycles via the minimum time between firing settings I will probably leave it alone until I am done tinkering with my wood setup.


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