storage was dowm to 86 F this morning

[JohnDolz]

Lol

I Have looked and cant locate some interior pics I had. The House was built around this massice cylinder tank and closet doors allow access on 2-3 floors?? For mainteneace and such.
Pretty cool, im keeping this all in mind for the retirement home

Very impressive! Certainly hope the "and such" never includes tank replacement!

 

[NP ALASKA]

Very impressive! Certainly hope the "and such" never includes tank replacement!

Found it, and yes tank replacement would be a expensive process.

 

[JohnDolz]

Lol

I Have looked and cant locate some interior pics I had. The House was built around this massice cylinder tank and closet doors allow access on 2-3 floors?? For mainteneace and such.
Pretty cool, im keeping this all in mind for the retirement home

Very impressive! Certainly hope the "and such" never includes tank replacement!

Found it, and yes tank replacement would be a expensive process.

You definitely need one of those! Very impressive.

 

[Woodfarmer1]

So if I'm following what you guys are saying, is I should let my systems circulator pump run all the time. My in floor radiant wasn't heating my house so I added two stelrad 8' rads to the far end of my great room.
I'm running a garn jr. Out in my shop. Over 12 hrs. The tank temp will drop from 180-190* down to 130-140 by morning.

 

[JohnDolz]

So if I'm following what you guys are saying, is I should let my systems circulator pump run all the time. My in floor radiant wasn't heating my house so I added two stelrad 8' rads to the far end of my great room.
I'm running a garn jr. Out in my shop. Over 12 hrs. The tank temp will drop from 180-190* down to 130-140 by morning.

I just started a new thread on low flow temps, you might find some good into there. I am not sure what size thermal storage you have with the Garn or what sqft you are heating but with radiant heating you should be able to get great use out of your storage. I do not have radiant heat but I am told that they use temps around 95F to heat in Europe (when radiant heating is present). It is a little more involved than just letting the circulator pump run. The idea is to only use as much (or little water) hot water from storage to hit your desired flow temperature. If we make an assumption that you could always use 95F water there would be a controller measuring the flow water temp and mixing hot water in with return so that the end result was 95F. With the Circulator always running your floor would hold a constant temp that would keep your house at desired temp. Hope that makes sense. I started a fire this AM around 7, got tanks to 190 and they are still at 182 (just took a look, in my thread I mistakenly said they were at 181 3 hours ago - I go into an Energy Saver Mode at 7:00 PM so I will use almost nothing until Recovery starts at 3:00 AM).

 

[Kristen]

Don't know if relevant, but we have Under Floor Heating in parts of the house, and Radiators in other parts. We run the radiators as hot as we can (heat is from a thermal store, so it varies from Max when boiler has charged and the store of approx 90C / 200F down to 40C / 100F when we are close to relighting the boiler)

The UFH still gives decent heat output at 40C, but its pointless putting that through the radiators.

We put water through the UFH which is just a few degrees warmer than the temperature we want in to the room (say 20C / 68F), and run the pump for long periods of time. We have hard tile floors, and it feels more comfortable to walk on them if they are not stone cold! plus we have huge thermal mass in the floors (the UFH pipe is buried deep in concrete, not in the surface screed), so we are looking to maintain that thermal mass "a bit warmer than the room". We increase the temperature, or the flow rate, if we have really cold weather, and cut it back in Autumn / Spring when the building is not losing much heat as outside temperature is mild. I expect there are weather-compensating controls which can do that sort of thing automatically, but I find that we only need a few settings / changes over the winter and I'm happy to do them manually.

I probably should alter the flow temperature to my radiators (i.e. so that it is constant), but we don't currently have that ability. It would probably help with maintaining stratification to my store, but we run our radiators ON when the boiler is lit (so that part of its heat goes into the building, and part into the store) because we have a batch log boiler and it must burn to completion (and if the store reaches Max temperature the boiler fan goes off and the wood smoulders [and is wasted]).

A friend of mind who has weather-compensation on his radiators does have that temperature adjustment, and says in the morning he reaches out of bed to feel if the radiator is hot, or warm, and then knows whether its a cold day ... or not!!

 

[jebatty]

My economical approach is to keep low temp emitters, especially pex in-floor in concrete, regulated at a constant temperature a little below the comfort level of the heated space. Concrete responds very slowly to temperature changes. That prevents over heating as outside temp increases, but also can result in under heating as outside temp decreases. Over heating is difficult to deal with, except through AC. Under heating is easy to deal with -- add a sweater or sweatshirt. An alternative would be to include supplemental heat to cover the under heating, but that could be expensive.

I follow this regimen in my shop, keeping the floor at a constant 61F, but probably would use a somewhat higher temp if a house. Although I can heat 1000 gal storage up to 190F, 170-180F is more normal, I mix supply to in-floor down to 100F. The floor has a sensor buried in the concrete that turns a circulator on/off to maintain the constant 61F.

 

[JohnDolz]

Don't know if relevant, but we have Under Floor Heating in parts of the house, and Radiators in other parts. We run the radiators as hot as we can (heat is from a thermal store, so it varies from Max when boiler has charged and the store of approx 90C / 200F down to 40C / 100F when we are close to relighting the boiler)

The UFH still gives decent heat output at 40C, but its pointless putting that through the radiators.

We put water through the UFH which is just a few degrees warmer than the temperature we want in to the room (say 20C / 68F), and run the pump for long periods of time. We have hard tile floors, and it feels more comfortable to walk on them if they are not stone cold! plus we have huge thermal mass in the floors (the UFH pipe is buried deep in concrete, not in the surface screed), so we are looking to maintain that thermal mass "a bit warmer than the room". We increase the temperature, or the flow rate, if we have really cold weather, and cut it back in Autumn / Spring when the building is not losing much heat as outside temperature is mild. I expect there are weather-compensating controls which can do that sort of thing automatically, but I find that we only need a few settings / changes over the winter and I'm happy to do them manually.

I probably should alter the flow temperature to my radiators (i.e. so that it is constant), but we don't currently have that ability. It would probably help with maintaining stratification to my store, but we run our radiators ON when the boiler is lit (so that part of its heat goes into the building, and part into the store) because we have a batch log boiler and it must burn to completion (and if the store reaches Max temperature the boiler fan goes off and the wood smoulders [and is wasted]).

A friend of mind who has weather-compensation on his radiators does have that temperature adjustment, and says in the morning he reaches out of bed to feel if the radiator is hot, or warm, and then knows whether its a cold day ... or not!!

Thanks the UHF comments certainly confirm the ability to use really low temps with that type of heating. I am no engineer so I can't explain the physics but based on my experience I would say that using a mixing valve would got you even further. As an example, like I mentioned above I heated my tanks to 190F yesterday morning, I went down to start a fire at 5:30 AM because I am leaving on a trip and wanted to leave my wife with fully charge tanks but the top tank was still at 164, almost 23 hours after I started my last fire - it is 21F outside. I had been lazy and not bothering to charge the tanks so high, I am amazed at how much more time I have gotten out of the tanks just because of those extra 10- 15 degrees (I had only been charging to 170 - 180 because I have been letting tank temp drop so low and too lazy to go add more wood).

 

[JohnDolz]

Thanks the UHF comments certainly confirm the ability to use really low temps with that type of heating. I am no engineer so I can't explain the physics but based on my experience I would say that using a mixing valve would got you even further. As an example, like I mentioned above I heated my tanks to 190F yesterday morning, I went down to start a fire at 5:30 AM because I am leaving on a trip and wanted to leave my wife with fully charge tanks but the top tank was still at 164, almost 23 hours after I started my last fire - it is 21F outside. I had been lazy and not bothering to charge the tanks so high, I am amazed at how much more time I have gotten out of the tanks just because of those extra 10- 15 degrees (I had only been charging to 170 - 180 because I have been letting tank temp drop so low and too lazy to go add more wood).

Sorry, I thought I was responding to a thread I had created on low flow temps, if you read that one my answer will make more sense.

 

[velvetfoot]

To play somewhat the devil's advocate, and also because I don't have a shunt setup as well as baseboard heat , one can't get blood from a stone. Would the zones just run for longer periods as the storage heat is drawn down, achieving the same thing as mixing as far as length of usable heat? At some late point they would be running nearly all the time. Less baseboard noise with constant cooling and reheating the slug of water in the baseboard loops would be a plus, for sure.

 

[maple1]

To play somewhat the devil's advocate, and also because I don't have a shunt setup as well as baseboard heat , one can't get blood from a stone. Would the zones just run for longer periods as the storage heat is drawn down, achieving the same thing as mixing as far as length of usable heat? At some late point they would be running nearly all the time. Less baseboard noise with constant cooling and reheating the slug of water in the baseboard loops would be a plus, for sure.

There's some cross thread talking going on now, with the other thread being started. But that's more or less what I'm experiencing. As my storage temps go down, my circs are on for longer, until it gets to the point that flow is constant. Then crosses to the point that the house starts losing temp. I think that last point would be about the same point you'd start a burn at whether mixing down or not - and no blood from a stone yet.

 

[JohnDolz]

There's some cross thread talking going on now, with the other thread being started. But that's more or less what I'm experiencing. As my storage temps go down, my circs are on for longer, until it gets to the point that flow is constant. Then crosses to the point that the house starts losing temp. I think that last point would be about the same point you'd start a burn at whether mixing down or not - and no blood from a stone yet.

Yes sorry about the cross thread, not quite sure how to undo it, maybe respond in the other thread and point folks to it? The blood comes from the stone earlier on. I think of it as cruise control vs. driving down the road stomping on the gas pedal, coasting, stomping, coasting. You will get to the same place but bet you have more gas left in the car if you used cruise control. The stingy use of the water when it is really hot is where you get the benefit. You are reusing the energy that is still left in the return water and adding just enough energy to keep the room temp constant. Setback and recovery does not do well in this environment. The controller in my boiler has the ability to use an Room Temp Sensor to temporarily override the outdoor rest heacurve but I am not convinced that there really is any overall gain. For example, this AM it was -6 outside, my recovery period starts at 3:00 AM, at 5:30 my flow temp was 50C as I was at the tail end of my recovery. Even at 50C it is low temp and my house struggles to get back to 72F (sorry about mixing C & F but that is the way I see the #'s so the way I remember them). before I had the shunt valve I tried letting tank temp drop down and see "low flow temps" worked, with no energy in the tanks and the house having already started cooling off I sank like a stone - no blood in sight.

 

[Kristen]

Would the zones just run for longer periods as the storage heat is drawn down, achieving the same thing as mixing as far as length of usable heat?

I would expect that to be the case .. but ... if the water temperature to the radiators is lower, heat will be drawn off at a slower rate, and if that is taken advantage of so that tank stratification is maintained (better than if using hotter water in radiators) then there might well be an advantage in being able to actually heat the house for a longer, overall, time.

 

[JohnDolz]

I would expect that to be the case .. but ... if the water temperature to the radiators is lower, heat will be drawn off at a slower rate, and if that is taken advantage of so that tank stratification is maintained (better than if using hotter water in radiators) then there might well be an advantage in being able to actually heat the house for a longer, overall, time.

Accor

I would expect that to be the case .. but ... if the water temperature to the radiators is lower, heat will be drawn off at a slower rate, and if that is taken advantage of so that tank stratification is maintained (better than if using hotter water in radiators) then there might well be an advantage in being able to actually heat the house for a longer, overall, time.

ding to my boiler manufacturer they said they were seeing about 25% gains overall. Of course there are so many variables and I do not know what "control" conditions were used to get to this 25% #. I was thinking about this earlier, I went from a 35kw (firebox holds 145 litres) to a 60kw (firebox hold 190 litres) and if I think about how I am burning I would say I am burning 1 load for every 2 that I used to burn (190 litres vs 290 litres - I do not actually weigh the wood). Keep in mind that I am using drier wood this year so I know some % of the gain gets attributed to that.

 

[velvetfoot]

Setback and recovery does not do well in this environment.

Exactly

It strikes me that fooling around with just supply temperatures from the tank alone is easier than when the boiler is also in the mix. It seems a good thing to tap the hot water for load when the boiler is running but the return temperature back to the boiler needs to be controlled. I am thinking that I should have put in an adjustable mixing valve, even a manual one, to play around with it some.

 

[velvetfoot]

Accor

ding to my boiler manufacturer they said they were seeing about 25% gains overall. Of course there are so many variables and I do not know what "control" conditions were used to get to this 25% #. I was thinking about this earlier, I went from a 35kw (firebox holds 145 litres) to a 60kw (firebox hold 190 litres) and if I think about how I am burning I would say I am burning 1 load for every 2 that I used to burn (190 litres vs 290 litres - I do not actually weigh the wood). Keep in mind that I am using drier wood this year so I know some % of the gain gets attributed to that.

Another factor could be that one continuous burn is more efficient that start-cool-start again. Since all excess heat goes to the tank. Did both models have lambda?

 

[JohnDolz]

Exactly

It strikes me that fooling around with just supply temperatures from the tank alone is easier than when the boiler is also in the mix. It seems a good thing to tap the hot water for load when the boiler is running but the return temperature back to the boiler needs to be controlled. I am thinking that I should have put in an adjustable mixing valve, even a manual one, to play around with it some.

I'll get a picture up at some point today or tomorrow of the mixing valve and motor, it is quite small and simple. I have a 4 pipe configuration (if I had to do it over again would probably do 2 pipe with vertical tanks) so my boiler is out of the supply loop (other than supplying the tank) but I would think the mixing valve would work equally well pulling water as it comes out of the boiler, just need to tie the return to it.

 

[JohnDolz]

Another factor could be that one continuous burn is more efficient that start-cool-start again. Since all excess heat goes to the tank. Did both models have lambda?

Yes and no. I have another thread going on this topic so it would be good to move this conversation there (not sure how to do that). If you go over there I posted a little info about how I am burning. Yes I agree with you in theory, no it is not the case with me because with the 35kw I would just keep throwing wood in it so it really had like a 9 hour burn plus a second (1 load 3-4 hour) burn - when it was really cold. Basically 2 burns (start and stop) on both boilers. Yes they both have Lamda. They are both Effecta's. With pulling water without a mixing valve the 35kw struggled to keep up. i think the 60kw is better sized for my needs but not sure what the 35kw would have been able to do if it had the benefit of a shunt valve.

 

[JohnDolz]

Another factor could be that one continuous burn is more efficient that start-cool-start again. Since all excess heat goes to the tank. Did both models have lambda?

Just posted some photos of the shunt valve and motor on the thread I had started "Heating with Low Temp Flow Water"