boiler question

[Mauler]

hi all, hope someone can help a dumb homeowner

I have had outdoor econoburn 150 (no storage) for 3000sqft, 20yo well insulated home with hot water baseboard (not low temp emitter) and my DHW is indirect hot water heater, my primary heat is an oil boiler which is fine, and I have been able to get by with only using it in the summer or when the wood boiler goes cold, and that has worked perfectly. I'm at 10-11 yrs with the econoburn and I think I might have to replace it. Its had some hiccups thru the years but otherwise it worked fine until recently. I wont get into whats wrong but am more interested in thinking about next season. My wood is free and high grade, well seasoned hardwood, in a 10 cord shed. this forum taught me everything about firewood and I do it pretty well.

option 1 is the simplest/cheapest, replace with same unit, if, and I mean IF I can get 10-15yrs or so out of a new econoburn 150 unit then that might be enough for me. (not doing this forever) I have a few big problems with that first option but I'd still consider it if the next option(s) are not feasible.

option 2 garn jr, always appealed to me because of integrated storage, except for the high temp water that I (think?) I need for my house. I'm home alot during the winter and can babysit a boiler if needed. Not that I want to but if it means I have greater long term durability/reliability then I'm still interested. With the batch burns it sounds like I'd need to start more fires to keep storage temp high, is that correct? I'm trying imagine what that would mean? new fires from scratch every 4 hrs? 8hrs? I'm also not clear if my existing pex (uponor ecoflex) is the proper size. I think mine is 1 inch, 1 supply, 1 return, and cannot be replaced (runs under a pool) so thats a deal breaker. Its also unpressurized, might need a HX?, and I'd need to build a shed for it but thats doable. Lastly I am not changing out any baseboards for low temp emitters, that's also deal breaker. So is garn jr realistic?

option 3 another outdoor gasser, years ago I considered portage main but I believe they are unpressurized, which I think means glycol and a HX? Maybe not a deal breaker because I could probably just use my existing foot print and add the HX somewhere inside...is that correct? Or maybe other brands? I use a competent hvac guy for the work, which is expensive around here, and try and diy when I can, but will never reach the engineer level that many on this forum are capable of. I am primarily interested in the return on investment, and enjoy the process of harvesting my own wood.

except for the garn I don't think I'm interested in cobbling together storage for any other gasser, I know its more efficient but if it faces the same hot water emitter issue as the garn then it seems moot...is that correct?

Thank you
signed
dumb homeowner

 

[Tonty]

Have you heard of or considered a Switzer boiler? I have one and I love it. It has integrated storage and is a batch burner, but unlike the Garn it is a pressurized unit. I have a small unit (600 gallons) as I’m from Kansas and couldn’t really justify a large one. I burn 70-90 pounds of wood every 12-24 hours. With the larger ones, the time between burns could increase. The unit is completely automatic once it’s started, and shuts itself off when the burn is done. It has multiple safety devices built in. Mr. Switzer recommends heating it to 220 degrees and then waiting until around 120 degrees to burn it again. I don’t take it quite that high, usually shooting for 200. I do not have any trouble whatsoever with gunky creosote buildup. The downside to them, perhaps, is that it’s a small company, although he has been building boilers for over 40 years, I believe. His shop is located in the state of New York.
I’m sure there are others on here who will have more recommendations for you, we all seem a bit prejudiced the type we have. 🤔

 

[Mauler]

Have you heard of or considered a Switzer boiler? I have one and I love it. It has integrated storage and is a batch burner, but unlike the Garn it is a pressurized unit. I have a small unit (600 gallons) as I’m from Kansas and couldn’t really justify a large one. I burn 70-90 pounds of wood every 12-24 hours. With the larger ones, the time between burns could increase. The unit is completely automatic once it’s started, and shuts itself off when the burn is done. It has multiple safety devices built in. Mr. Switzer recommends heating it to 220 degrees and then waiting until around 120 degrees to burn it again. I don’t take it quite that high, usually shooting for 200. I do not have any trouble whatsoever with gunky creosote buildup. The downside to them, perhaps, is that it’s a small company, although he has been building boilers for over 40 years, I believe. His shop is located in the state of New York.
I’m sure there are others on here who will have more recommendations for you, we all seem a bit prejudiced the type we have. 🤔

Thank you for the suggestion

I have heard of it from reading this forum, but if letting it cool to 120 degrees is the only way to get the 12hrs intervals when its cold out, then my understanding is my baseboard will not be able to produce enough heat. Am I correct? What if I need 150-180 degree water constantly? (and I think I do), how often would I need to fire the switzer? and how practical is that? Can I adjust the temp range so that it heats up the storage once it drops below 160 degrees? I'm guessing you have low temp emitters? Is there a reasonable expectation that I can maintain higher temps?

 

[Bad LP]

Take your DHW off the wood boiler.
I’m going that route because the DHW just isn’t hot enough for my liking.

 

[Tonty]

I don’t have baseboard heaters, I have floor heat, a coil in a forced air unit, and a DHW coil that goes into the boiler. It works fine for any of those scenarios. When you say “ Can I adjust the temp range so that it heats up the storage once it drops below 160 degrees?”, yes you can. You would just need to go light the boiler when it gets to that temp. I have never had any other boiler (I heated with a wood stove before this), so I’m not sure how that compares to others. With the Switzer, you don’t leave any unburned or smoldering wood in it. When a batch is done, it’s out and cold (so to speak) until you light it again. It is very easy to light. There be are some others on here with a bigger units and in a colder climate, they could perhaps answer the question of longer times between burns with those units.

 

[brenndatomu]

option 3 another outdoor gasser, years ago I considered portage main but I believe they are unpressurized, which I think means glycol and a HX? Maybe not a deal breaker because I could probably just use my existing foot print and add the HX somewhere inside...is that correct? Or maybe other brands? I use a competent hvac guy for the work, which is expensive around here, and try and diy when I can, but will never reach the engineer level that many on this forum are capable of. I am primarily interested in the return on investment, and enjoy the process of harvesting my own wood.

This ^ ^ ^ specifically an EPA 2020 certified model that is over 75% efficiency so that it qualifies for the 26% tax credit this year and next.
I don't think the unpressurized part matters...could be wrong... @E Yoder would know about that...

 

[salecker]

Hi
I am curious about your Econoburn.
I am on year 13 or 14 with mine and don't see anything to make me think it will not make another 20 years.
If you feel more comfortable to PM me about it that would be fine.Maybe there is something that i can help with so you don't have to change boilers.
I have the 200 outdoor model but with storage,and i built a building to house my system.

 

[Mauler]

Hi
I am curious about your Econoburn.
I am on year 13 or 14 with mine and don't see anything to make me think it will not make another 20 years.
If you feel more comfortable to PM me about it that would be fine.Maybe there is something that i can help with so you don't have to change boilers.
I have the 200 outdoor model but with storage,and i built a building to house my system.

I might PM you so thank you for that. For now let me try and simplify my original post, is it perfectly true that high temps are needed for standard baseboard heaters? and if true will garn deliver that needed temp without going through some kind of excessive effort to maintain that high temp. I know that all situations are different but assuming a well insulated 20yo old home, great undergound lines with no loss, great wood, etc. I am not willing to modify to low temp emitters.

If I do in fact need that high temp, I get the impression that garn will not be able to do what I want, or at least will not be able to do it without some compromise (like short intervals between fires or a very slow to heat house) nor will any storage type setup either, leaving me with the usual stand alone gasser type scenario during which I will have excessive idling and probably destroy the chamber walls in a few years. I do plan on calling dectra for their take but this forum is a great resource.

 

[peakbagger]

With storage I would need to add a heat exchanger or an extra coil. My solar hot water system is inadequate for winter except for preheat. Someone had given me a boilermate tank that is heated with an extra zone so I rigged it up so that when I am done charging my storage and have a hot boiler I charge up the hot water tank to 180 F. The hot water system is preheated by solar so that boilermate full of 180 F water lasts 24 hours or more. Unfortunately the controls on that system decided to stop working and its hard to diagnose wiring on crutches. Worst case is my SHW tank has an electric backup coil but I hate keeping it hot 24/7.

Yes its true modern slant fin radiators were designed for high supply temps. They will put out heat at lower temps but it just takes a lot more of them. There is also an issue that you cannot run a super long length of slant fin as at some point the water cools down too much. I have seen where folks have 2 or three strips of slant fin inside a custom convector box. The strips are fed in parallel to keep supply temps high with the loops kept short. Most heating companies use standard tables for output and put in the bare minimum length. There also can be hydraulic issues in that the supply piping could be undersized for the amount of flow you are trying to push through the pipes. Add in that as the temps drop the heating load goes up and in most cases the installed radiation cant match the heat loss out of the house. Many radiators are also limited by furniture and other stuff blocking convective flow. There has to be space for cool air to run along the floor into the slant fin and then space for heat to rise. In many cases furniture is pushed right up against it. I have the same issue that once my storage drops to 140, I do not have enough radiation. I have tried lots of things but the net result is my oil backup clicks on when the tank drops below 140F. I could upgrade to low temp hydronic emitters but I cannot justify the cost given my low wood use.

 

[Bad LP]

With storage I would need to add a heat exchanger or an extra coil. My solar hot water system is inadequate for winter except for preheat. Someone had given me a boilermate tank that is heated with an extra zone so I rigged it up so that when I am done charging my storage and have a hot boiler I charge up the hot water tank to 180 F. The hot water system is preheated by solar so that boilermate full of 180 F water lasts 24 hours or more. Unfortunately the controls on that system decided to stop working and its hard to diagnose wiring on crutches. Worst case is my SHW tank has an electric backup coil but I hate keeping it hot 24/7.

Yes its true modern slant fin radiators were designed for high supply temps. They will put out heat at lower temps but it just takes a lot more of them. There is also an issue that you cannot run a super long length of slant fin as at some point the water cools down too much. I have seen where folks have 2 or three strips of slant fin inside a custom convector box. The strips are fed in parallel to keep supply temps high with the loops kept short. Most heating companies use standard tables for output and put in the bare minimum length. There also can be hydraulic issues in that the supply piping could be undersized for the amount of flow you are trying to push through the pipes. Add in that as the temps drop the heating load goes up and in most cases the installed radiation cant match the heat loss out of the house. Many radiators are also limited by furniture and other stuff blocking convective flow. There has to be space for cool air to run along the floor into the slant fin and then space for heat to rise. In many cases furniture is pushed right up against it. I have the same issue that once my storage drops to 140, I do not have enough radiation. I have tried lots of things but the net result is my oil backup clicks on when the tank drops below 140F. I could upgrade to low temp hydronic emitters but I cannot justify the cost given my low wood use.

100% of my experience with base board. I’m lucky in that every BB zone was home run but I am still going to run a panel radiator in the master bedroom as a test.

 

[Mauler]

just to be clear with the consistent high temps that that econoburn (and other stand alone gassers no doubt) produces my baseboard is definitely adequate, I don't want more baseboard and will not add more. If the garn or other storage type setups are ONLY for low temp emitters or oversized runs of standard baseboard then that's what I need someone to tell me.

 

[maple1]

just to be clear with the consistent high temps that that econoburn (and other stand alone gassers no doubt) produces my baseboard is definitely adequate, I don't want more baseboard and will not add more. If the garn or other storage type setups are ONLY for low temp emitters or oversized runs of standard baseboard then that's what I need someone to tell me.

I wouldn't say they are ONLY for low temp emitters. Just that if your emitters aren't low temp emitters, or aren't sized for lower supply temps, then you will have to fire it more often. So a Garn, or any boiler/storage combo for that matter, will give much more optimized results if also used in conjunction with low temp emitters.

I have ordinary Slant Fin but after using it with my boiler/storage setup for a while came to the conclusion it was oversized design-wise when it was first installed. I can maintain house temps down to supply temps of 130-140 or so, depending on the day. Then I need to light up again. I could lower that by adding in some cast iron rads but my other half has an aversion to them. For some reason.

 

[salecker]

Do you have anywhere you could add storage?
It can be anywhere,preferably in a space you use.Carport,basement,add a room to your house?
Having storage will give you more hot water after the boiler has shut down.
With my system i start one fire a day,i have cast iron rads so i get heat out of my storage in the lower temps,my backup oil comes on when my storage hit's 110F

 

[Mauler]

I wouldn't say they are ONLY for low temp emitters. Just that if your emitters aren't low temp emitters, or aren't sized for lower supply temps, then you will have to fire it more often. So a Garn, or any boiler/storage combo for that matter, will give much more optimized results if also used in conjunction with low temp emitters.

I have ordinary Slant Fin but after using it with my boiler/storage setup for a while came to the conclusion it was oversized design-wise when it was first installed. I can maintain house temps down to supply temps of 130-140 or so, depending on the day. Then I need to light up again. I could lower that by adding in some cast iron rads but my other half has an aversion to them. For some reason.

thats what i am wondering, as a hypothetical, how long in between fires is it on the coldest day vs on a warmer day (but still needs heat), lets say a cold february day vs a moderate november day? also how much sq ft are you heating. and are you also heating domestic hot water with 3 teens in the house. I know its not a garn I'm but just shooting from the hip to get some sense of how it might work for me.

 

[Mauler]

Do you have anywhere you could add storage?
It can be anywhere,preferably in a space you use.Carport,basement,add a room to your house?
Having storage will give you more hot water after the boiler has shut down.
With my system i start one fire a day,i have cast iron rads so i get heat out of my storage in the lower temps,my backup oil comes on when my storage hit's 110F

If I can do storage, and the lower water temps, then I'd just go ahead and get a garn, I can build a shed to house it where the econoburn sits right now (which is outside). From what I can tell from this forum it is unlikely that I will be able to use 110 heat. I'm not even sure if 140-150 degree is useful. Pretty sure that during the install my econoburn was set to stop circulating water at 150 or so, which seems to make sense since i might not get be able to use temps lower then that.

What I dont want is to have a garn drop to 150 degrees quickly and then my oil kicks on, if its under 8 hrs I'd say thats quick. Granted on the coldest days around here I might expect to do 3 fires a day but I dont want to do that on the warmer days.

I'm sure knowing with 100% certainty is impossible, but I appreciate everyone's response's

 

[maple1]

thats what i am wondering, as a hypothetical, how long in between fires is it on the coldest day vs on a warmer day (but still needs heat), lets say a cold february day vs a moderate november day? also how much sq ft are you heating. and are you also heating domestic hot water with 3 teens in the house. I know its not a garn I'm but just shooting from the hip to get some sense of how it might work for me.

We have 2700 sq.ft. in two stories over 1500 of unfinished and unheated basement where the boiler is. Unheated except for standby heat loss from the boiler/storage. 25 year old construction. On an open hill top in northern NS. Climate kind of moderate.

System has around 700 gallons of water. Distribution is Slant Fin, in 4 zones. 2 up where bedrooms are and 2 down where kitchen, living room, dining room and office are. My daily schedule in winter is make a fire late afternoon. Time to build and light maybe 5-10 minutes. With maybe half a firebox. Come back in half an hour and load full with wood. Come back in 3 hours or so and load full again. Fire is out when I'm heading to bed. Repeat next day. The very coldest days I might start early afternoon and load another load in.

I also use setbacks on the thermostats to get more time between fires. All zones set back a couple or few degrees overnight. Upstairs stays back until supper time when I have a fire going. Downstairs depends on who is home doing what. All get turned back up a couple degrees more than 'normal'when I have a fire going. Sending extra heat to the house during that time. I would ideally like to have more storage but don't have the room for it without doing some major rearranging down there. I could also get more out of my storage if I plumbed in a cast iron rad on the ends of my zones, which is in a bathroom in 3 out of 4 of them. But got a no-go on that idea. Swapping Slant Fin for panel rads or other low temp emitters would also do it. Or adding more Slant Fin.

Another thing with the Garn is that since it is open, but the distribution is closed/pressurized, you would need to use a heat exchanger in between. Which means you won't get quite all the useable heat out of the water compared to if it was all one pressurized system. (I think).

 

[maple1]

Also, it's a bit hard to come up with specific recommendations without knowing what the issue is with your current boiler. Without knowing, my first option I would be looking at would be getting an insulated structure up around your Econoburn, big enough to also give some heated work/shop space, and adding storage to it, either in the boiler structure or your house. That's kind of assuming whatever the issues are with your current unit are somehow related to idling. From all the reading on here I would expect an EB to last way longer than that. As Salecker has already testified to.

But, different strokes....