Indoor wood boiler

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SpaceBus

Minister of Fire
Nov 18, 2018
5,945
Downeast Maine
Ah those look slick. Suppose if I could have them build a taller skinny one it wouldn’t be so bad.
I've seen another member here use an old tank that looked like a refrigerator, maybe it was a milk tank or something. How large is your home? The larger the storage the longer you can go between batch burning. If your house is not huge and you don't mind burning a few batches per day 550 gallons would be fine. You certainly won't get creosote accumulating in the stove with storage, and you can get used to burning what you have and upgrade later. I'm sure the minisplits weren't cheap, but they will also be able to carry the majority of your heating load during the year. Then the boiler with storage would be more than capable of handing the house during the cold parts of winter. I'm sure once you experience the radiant heat from the boiler and storage you won't even want to use the minis ;lol
 

Cashius23

New Member
Feb 4, 2021
16
Iowa
I've seen another member here use an old tank that looked like a refrigerator, maybe it was a milk tank or something. How large is your home? The larger the storage the longer you can go between batch burning. If your house is not huge and you don't mind burning a few batches per day 550 gallons would be fine. You certainly won't get creosote accumulating in the stove with storage, and you can get used to burning what you have and upgrade later. I'm sure the minisplits weren't cheap, but they will also be able to carry the majority of your heating load during the year. Then the boiler with storage would be more than capable of handing the house during the cold parts of winter. I'm sure once you experience the radiant heat from the boiler and storage you won't even want to use the minis ;lol
It’s 1344sq ft main. No heat in basement yet maybe someday. It’s a Wausau home built in 72. Has newer windows and it’s well insulated. My heat loss is around 36k btu on a -1 degree day. I’ve got 81’ of baseboard so I’m at around 45k btu output at 180 degree water. My Weil McLain is 88k output and the wood boiler is 150k. I found the old manual for it. The minisplit is great for mornings to just take the chill off when it’s going to be warm during the day or I get lazy or propane skyrockets. I got it at cost so I’m not to much money into it. Our last house I put an insert in the basement and heated it mostly with that so I’m not completely new to burning wood. I moved all my wood from the other house and just brought home 2 trailer loads of ash. I’m ready to burn lol.
 

SpaceBus

Minister of Fire
Nov 18, 2018
5,945
Downeast Maine
It’s 1344sq ft main. No heat in basement yet maybe someday. It’s a Wausau home built in 72. Has newer windows and it’s well insulated. My heat loss is around 36k btu on a -1 degree day. I’ve got 81’ of baseboard so I’m at around 45k btu output at 180 degree water. My Weil McLain is 88k output and the wood boiler is 150k. I found the old manual for it. The minisplit is great for mornings to just take the chill off when it’s going to be warm during the day or I get lazy or propane skyrockets. I got it at cost so I’m not to much money into it. Our last house I put an insert in the basement and heated it mostly with that so I’m not completely new to burning wood. I moved all my wood from the other house and just brought home 2 trailer loads of ash. I’m ready to burn lol.
Something else to consider, one big downside to the OWB is going outside in the cold winter to feed the fire. I know to some that is an advantage. The Heatmaster G series are supposed to be very clean burning and efficient without additional storage, if you are committed to the OWB route. I would think your house would be just fine with 500+ gallons of storage, but there are calculators that more boiler savvy folks could probably chime in with. All of the OWB's on the market are probably overkill for your house as well, and the indoor unit will probably heat the basement just by being in it.
 
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andym

Feeling the Heat
Feb 6, 2020
424
Hicksville, Ohio
A propane tank is out of the question as it wouldn’t fit. The only way would be if I build one or buy smaller storage tanks somewhere. I also don’t know how much storage I would need. I know my heat loss and everything I just need to figure it. I’d have to feed the wood through a window somewhat close to the boiler otherwise haul it downstairs and across the living room to the boiler room. I’ve got a shop I’d also like to heat is another factor for ditching the indoor.
You won't regret going with the outdoor boiler. Go with either Polar Furnace or Heatmaster and skip the storage. If you have baseboard radiators you will not really be able to utilize storage all that well due to needing really hot water temps.
Wood handling can make or break an indoor setup. I've got a wood chute system as well as a holding bin and additional stacking space. I would never want to carry all my wood through a doorway, down steps, or any other unhandy way.
Heating more than one building is where outdoor units shine. Assuming proper insulated lines are used.
 

andym

Feeling the Heat
Feb 6, 2020
424
Hicksville, Ohio
Before you cut up all the indoor boiler stuff, are you sure you want an outdoor system? That boiler got all covered in creosote because it wasn't being burned appropriately. An indoor boiler really needs storage to not accumulate tons of creosote and smoke up your outdoor space. Outdoor boilers don't always need storage, but you will have to add a lot of plumbing. With your house being already set up for the indoor boiler, I would be figuring out a way to get storage in there and just burn the old boiler.
Other than the old boiler what does he need to tear out? Won't he be reusing all of the existing plumbing? Just hook the incoming lines up to where the current boiler is connected. Seems to me that the OWB would require much less changes than a new indoor boiler with storage.
If pressurized storage would indeed be too difficult to install, I would be quick to recommend an outdoor boiler.
 

Cashius23

New Member
Feb 4, 2021
16
Iowa
I'm pretty sure your wood boiler wasn't delivering anywhere close to 150k.
The manual estimated that so that’s where I got it from.
You won't regret going with the outdoor boiler. Go with either Polar Furnace or Heatmaster and skip the storage. If you have baseboard radiators you will not really be able to utilize storage all that well due to needing really hot water temps.
Wood handling can make or break an indoor setup. I've got a wood chute system as well as a holding bin and additional stacking space. I would never want to carry all my wood through a doorway, down steps, or any other unhandy way.
Heating more than one building is where outdoor units shine. Assuming proper insulated lines are used.
I can heat the house at 0 degrees with 150 degree water right now and at 30 degrees I’m at 130 degree water. I could easily add more baseboard to get it even lower. I’ve got a 36x52 shop I had concrete poured in. It will be insulated someday. That’s why I’m more leaning towards outdoor.
 

maple1

Minister of Fire
Sep 15, 2011
10,783
Nova Scotia
The manual estimated that so that’s where I got it from.

I can heat the house at 0 degrees with 150 degree water right now and at 30 degrees I’m at 130 degree water. I could easily add more baseboard to get it even lower. I’ve got a 36x52 shop I had concrete poured in. It will be insulated someday. That’s why I’m more leaning towards outdoor.
What are your plans for that shop? Could you wall off an area big enough for a boiler and wood? Some OWBs can be installed indoors also. I think. Then you'd capture stand by heat loss in a usable space.
 
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SpaceBus

Minister of Fire
Nov 18, 2018
5,945
Downeast Maine
What are your plans for that shop? Could you wall off an area big enough for a boiler and wood? Some OWBs can be installed indoors also. I think. Then you'd capture stand by heat loss in a usable space.
I think even the smaller OWB might idle a lot without storage on a 1500 sqft house.
 

Cashius23

New Member
Feb 4, 2021
16
Iowa
What are your plans for that shop? Could you wall off an area big enough for a boiler and wood? Some OWBs can be installed indoors also. I think. Then you'd capture stand by heat loss in a usable space.
It'll be mostly for wrenching and holding my projects. Don’t want to give up too much real estate. I’ve got an old foundation that sets back a little and nearly halfway between house and shop I thought about putting a boiler on that. I wouldn’t mind building a shelter for it but lumber and steel is so damn expensive still. The other issue is getting the old one out in one piece. It weighs 790lbs. I suppose if I get some storage in the basement I can clean the old one out good and run it until I get my shop ready. Then make a decision.
 
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SpaceBus

Minister of Fire
Nov 18, 2018
5,945
Downeast Maine
It'll be mostly for wrenching and holding my projects. Don’t want to give up too much real estate. I’ve got an old foundation that sets back a little and nearly halfway between house and shop I thought about putting a boiler on that. I wouldn’t mind building a shelter for it but lumber and steel is so damn expensive still. The other issue is getting the old one out in one piece. It weighs 790lbs. I suppose if I get some storage in the basement I can clean the old one out good and run it until I get my shop ready. Then make a decision.
Solid plan. The storage can also be used with an OWB, if you decide to go that route.
 

salecker

Minister of Fire
Aug 22, 2010
1,437
Northern Canada
The manual estimated that so that’s where I got it from.

I can heat the house at 0 degrees with 150 degree water right now and at 30 degrees I’m at 130 degree water. I could easily add more baseboard to get it even lower. I’ve got a 36x52 shop I had concrete poured in. It will be insulated someday. That’s why I’m more leaning towards outdoor.
Put the boiler in the shop with storage.
I have a dedicated building for my boiler and storage.My backup oil boiler is in there as well.
So i have no fire in my home or chance of any carbon monoxide poising.No mess,ash or smoke in my home.My heating system in it's own building is my fire insurance.There is no fire department here,just volunteers.
Plus i have a heated workspace 24/7.
It's a 125 ft walk one way.Even at -40 i wouldn't have it any other way.
I have an Econoburn outside boiler that ended up inside.1000 gals storage.
The Econoburn is built like a tank,11 years use now,i don't see why it wouldn't last for another 25 years
 

E Yoder

Minister of Fire
Jan 27, 2017
555
Floyd, VA
One thing I thought I'd mention, heat loss off the newer owb-style boilers is pretty minimal. I don't think you'll hear a shop more than a few degrees warmer by putting it indoors. You'll need a blower/coil or something on a thermostat. Blow it at your feet and you'll feel the heat quickly.
 
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Cashius23

New Member
Feb 4, 2021
16
Iowa
Put the boiler in the shop with storage.
I have a dedicated building for my boiler and storage.My backup oil boiler is in there as well.
So i have no fire in my home or chance of any carbon monoxide poising.No mess,ash or smoke in my home.My heating system in it's own building is my fire insurance.There is no fire department here,just volunteers.
Plus i have a heated workspace 24/7.
It's a 125 ft walk one way.Even at -40 i wouldn't have it any other way.
I have an Econoburn outside boiler that ended up inside.1000 gals storage.
The Econoburn is built like a tank,11 years use now,i don't see why it wouldn't last for another 25 years
I wouldn’t be apposed to building a building strictly for a boiler and storage someday. Or at least the storage tanks or whatever I use. That’d clear up some real estate in the basement. Lot of ways a guy can go with this stuff it’s hard to make a decision. I think if I can get this boiler cleaned up and some storage I’ll run it for awhile until I can make up my mind.
 

peakbagger

Minister of Fire
Jul 11, 2008
6,346
Northern NH
I installed one of the American Solar Technics tanks. Its assembled in place and is rectangular so it takes up less space than an equivalent round tank or cylindrical tank. It is not pressurized. There is a couple of feet of space on the top of it needed to assemble it and install the coils. They are very careful to warn that the top cover is not be used for storage. I installed some "hoops" made out of 2x4s hanging down from the floor joists above. I slid some boards in from the side and can store stuff over the tank while not putting any load on it. Yes it still takes up room but a lot less than the traditional round pressurized tank. All the parts can be carried by one person through a standard door down a set of standard stairs and assembled in place.

Ideally I would swap over my radiators with radiant emitters so I drop my supply temps. As currently operated I bring it up to 185 F and run down to 140F. In real cold weather (-30F) I need to burn twice a day but anything over -10 at night I can run 24 hours. If I went with lower supply temp emitters I could run longer but would need to burn longer to charge it back up. My boiler is nameplate of 100,000 btu/hr so it takes me about 3 hours of burning to bring the tank up from 140 to 185.
 

Cashius23

New Member
Feb 4, 2021
16
Iowa
I installed one of the American Solar Technics tanks. Its assembled in place and is rectangular so it takes up less space than an equivalent round tank or cylindrical tank. It is not pressurized. There is a couple of feet of space on the top of it needed to assemble it and install the coils. They are very careful to warn that the top cover is not be used for storage. I installed some "hoops" made out of 2x4s hanging down from the floor joists above. I slid some boards in from the side and can store stuff over the tank while not putting any load on it. Yes it still takes up room but a lot less than the traditional round pressurized tank. All the parts can be carried by one person through a standard door down a set of standard stairs and assembled in place.

Ideally I would swap over my radiators with radiant emitters so I drop my supply temps. As currently operated I bring it up to 185 F and run down to 140F. In real cold weather (-30F) I need to burn twice a day but anything over -10 at night I can run 24 hours. If I went with lower supply temp emitters I could run longer but would need to burn longer to charge it back up. My boiler is nameplate of 100,000 btu/hr so it takes me about 3 hours of burning to bring the tank up from 140 to 185.
I’m gonna email them once I figure out what I want for sizing. I’d like it to be as tall as possible with just enough room to get the lid off and hx coil out if I ever need it. I’ve been looking at how I can get more btus out of the baseboard i got. Weather it’s put in high output or double it up in sections. I figured out most of the formulas so now I can play with the numbers. Nothing but good advice and lots of knowledge on here thanks.
 
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maple1

Minister of Fire
Sep 15, 2011
10,783
Nova Scotia
I’m gonna email them once I figure out what I want for sizing. I’d like it to be as tall as possible with just enough room to get the lid off and hx coil out if I ever need it. I’ve been looking at how I can get more btus out of the baseboard i got. Weather it’s put in high output or double it up in sections. I figured out most of the formulas so now I can play with the numbers. Nothing but good advice and lots of knowledge on here thanks.
When my Slantfin baseboard was installed they ran the housing and pipe wall to wall but only put the amount of fin tube in that the design spec'd. I.e. more housing than fins. So it is pretty easy to add more fin tube.