Is it possible for a smaller stove to have higher BTU

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Abstovehunter

New Member
Dec 10, 2021
13
alberta
Hi folks, I am new to the forum.

I am hoping someone can clarify some stove sizing concerns I have. I am looking for a wood cookstove used mainly to heat and for occasional and back up power outage use. I am currently running a stove in a roughly 2400 sf home and it is running hard around -20. That's the coldest we've seen so far, but -30 to -40 is far from unusual for at least a couple weeks every year.

The house is new and I am running an Archguard Chalet 1800, 35,000 BTU stove that was brought over from the last house to see how well it would work before sizing the stove we want for this house. Firebox is 17” w x 12” h x 20” d. 2.3cf

The stove I originally intended to put in is the Rosa XXL, rated at 30,000 BTU and the firebox is 11.7" W x 12" H x 18.1" D. 1.47cf. I am now thinking this will be too small based on the performance of the above stove. I do not know how thermal mass will play into the equation as the XXL is a lot more stove, but I am searching for something with higher BTU to err on the side of caution.

Enter the Bun Baker, which is rated at 65,000 BTU. The firebox is 19" W x 13" H x 11" D. 1.5cf. There was a detailed review of it, the owner was heating a 2 story 2400 sq ft house. They cut a hole in the floor above the stove to circulate the heat and say it is working amazingly well. They did not, however, share their location. Arizona vs Alberta?

I understand that if the firebox is larger you can fit more fuel and BTU in it. I do not understand how you can get more BTU out of a smaller firebox, so my concern is that the stove I am running now has the largest firebox of them all and is running hard at -20. Could the 65,000 BTU's be accurate or will I find the company has just over rated it and it won't be big enough either? Or, is it possible the stove I really want (number B) which they claim is under rated at heating 1500sf, and can heat larger well insulated spaces (ie- my new house) might actually suffice.

Hoping someone smarter than me can shed some light on things.

Cheers!
 
Well yes a smaller stove can have higher BTUs if you release the heat from that wood over a shorter period of time. Not really any other way to do it. Increasing efficiency will help but most modern stoves are already pretty efficient.


Have you ever considered a stove for heating purposes and then the cook stove.
 
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I have to concur with what @bholler said above. I own a Bun Baker XL and really like it, but I can tell you with the size of the firebox, which is on the smaller size (depth), I split regular size splits down into 3-4 smaller splits, and even use a good number of these cut in half so I can load them in North/South with the longer splits East/West, and I stack them. I find this does a good job of heating my house, but it does require loading more often since the smaller splits burn faster/hotter. Using regular size splits, I don't get as good a fire and less heat output. At most, you can fit 3 large splits, but they just don't seem to burn as well. Who knows, I've only been burning wood less than a year (since last January). Maybe I am doing something wrong.
 
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I would be looking at 3 cu ft firebox stoves if I were you, you’ll need that larger firebox come colder weather. Manufacture btu numbers are misleading because of the different testing methods and marketing.
 
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Well yes a smaller stove can have higher BTUs if you release the heat from that wood over a shorter period of time. Not really any other way to do it. Increasing efficiency will help but most modern stoves are already pretty efficient.


Have you ever considered a stove for heating purposes and then the cook stove.
Thanks. This pretty well sums up my concern. What I am grasping is that I may get the heat, but I will have to run full out.

I would love to have both. I pulled out an indoor/outdoor gas fireplace which was set in a build out and I used fireboard and tile to create an alcove that provides the biggest space possible to accomodate a cookstove. A second stove would be difficult due to build restrictions. The house is open concept with windows everywhere. A second stove would require some destruction, and possibly sacrificing storage and function.
 
I would be looking at 3 cu ft firebox stoves if I were you, you’ll need that larger firebox come colder weather. Manufacture btu numbers are misleading because of the different testing methods and marketing.

Thank you both. I was implying this with my statement on over rating a stoves BTU. I have been bitten in the past when I questioned something based on logic and went with optimism that it will work, only to find the manufacturer had tweaked the numbers and performance was dissapointing.
 
I am currently trying to figure out how to extend the front entry onto the covered deck to allow space for a closet, so I can turn the entry closet into an alcove for a second stove.

It's going to take some thinking, but a second stove was already an interest for even heating. We manage with a ceiling fan in the main area by the stove and a plug in fan in the bedroom at the far end, but a second heat source on the opposite end would be ideal.

Thanks for confirming my concerns and giving me something to think about.
 
A thought that just came to mind. If I couldn't find an adequate cookstove. I was going to put a much large woodstove in the alcove.

If I buy the 30,000 btu cookstove and move the currently installed 35,000 woodstove to the end of the hallway should I be considering a 75000 btu 3+cf stove for the main stove to replace the 35,000 so that I have the option for longer burns? I understand the concerns of oversizing, but you can run a small fire hot just to take the chill off the back area, or just use one stove during warmer weather and circulate air. You don't need to choke a fire to control it. Does 2 moderately sized stoves make sense to work to together or is it smarter to make sure there is a real heater in the mix.

Our last house was heated only with wood. It's not a worry of if it's possible, just how it makes sense when heat is the goal, but not having the cookstove would be a great dissapointment, especially after designing the alcove for one.

Should I also be considering catolytic, or pellet for the main heater. I would prefer to avoid electrical requirements, there is an element of 'just in case' in my motivations.
 
Thanks. This pretty well sums up my concern. What I am grasping is that I may get the heat, but I will have to run full out.

I would love to have both. I pulled out an indoor/outdoor gas fireplace which was set in a build out and I used fireboard and tile to create an alcove that provides the biggest space possible to accomodate a cookstove. A second stove would be difficult due to build restrictions. The house is open concept with windows everywhere. A second stove would require some destruction, and possibly sacrificing storage and function.
Check alcove clearance requirements for the stoves you look at many times they are much larger than the regular clearances
 
How close would a woodstove be to the kitchen if only one stove in the current location? How much stovetop cooking do you anticipate on the stove, especially if it is not close to the kitchen? How much oven baking?
 
Check alcove clearance requirements for the stoves you look at many times they are much larger than the regular clearances
Thanks, I am working with a certified installer to make sure I meet requirements. He installed the chimney, I just did the construction to his specifications. He is going to come inspect and certify it when it is finalized.
 
Pellet costs in Alberta are ridiculous compared to natural gas, I wouldn't consider it an option.

Catalytic could be an option, but 3cu ft is probably the smallest you want to consider in that case. You're a good candidate for a BK king or Regency F5200, but both those require an 8" flue.

There also a pile of options for non-cat stoves too, just depends on what area of the province you are in and what dealers nearby carry.

I won't entertain the idea of heating your home with a cook stove, IMO anything under 2 cuft is grossly undersized for your home, unless your house is insulated well beyond what code requires.
 
How close would a woodstove be to the kitchen if only one stove in the current location? How much stovetop cooking do you anticipate on the stove, especially if it is not close to the kitchen? How much oven baking?
The wood stove is 12 feet from the kitchen island, 20 feet from the stove. I would likely simmer stock on the stove, which I make often, and reheat food instead of preheating the oven. Buns in the oven every once in awhile.

Honestly the cookstove is romantic/idealistic. The reality is I am busy, I work alot. I rarely have time for baking. Will I use it alot? Not likely. I am hoping I am surprised at how much it will be used, but will I appreciate it when the power is out? You bet. Our cooktop is gas, but oven is electric, and it is nearly imposible to find a gas oven that does not require significant power these days.
 
Thanks, I am working with a certified installer to make sure I meet requirements. He installed the chimney, I just did the construction to his specifications. He is going to come inspect and certify it when it is finalized.
Make sure the installer understands and follows clearances as well
 
The wood stove is 12 feet from the kitchen island, 20 feet from the stove. I would likely simmer stock on the stove, which I make often, and reheat food instead of preheating the oven. Buns in the oven every once in awhile.

Honestly the cookstove is romantic/idealistic. The reality is I am busy, I work alot. I rarely have time for baking. Will I use it alot? Not likely. I am hoping I am surprised at how much it will be used, but will I appreciate it when the power is out? You bet. Our cooktop is gas, but oven is electric, and it is nearly imposible to find a gas oven that does not require significant power these days.
In that case personally I don't see how the compromises and added cost of a cookstove make any sense
 
Pellet costs in Alberta are ridiculous compared to natural gas, I wouldn't consider it an option.

Catalytic could be an option, but 3cu ft is probably the smallest you want to consider in that case. You're a good candidate for a BK king or Regency F5200, but both those require an 8" flue.

There also a pile of options for non-cat stoves too, just depends on what area of the province you are in and what dealers nearby carry.

I won't entertain the idea of heating your home with a cook stove, IMO anything under 2 cuft is grossly undersized for your home, unless your house is insulated well beyond what code requires.
It is well insulated. R30 walls, R40 floor, R60 ceiling, triple pane windows. I agree though, I am already over 2cf and running hard at -20. The main reason for the question was to ensure I don't sacrifice the heating capablities for the novalty of a cookstove. The furnace is always a backup option, but I have an endless supply of free wood on the property. I used 20% of the propane tank in the month before the stove was installed and 5% in the 2 months since. Before moving into this home (same property) we were going through a propane tank a year. Dryer, stove and hot water are gas. Cost is roughly $600 a year, so I will never see the benefit of $5000 to install NG if I get the stove sizing right.

I just installed a 6 inch flue so I would rather not upgrade to 8". I think I would prefer not to go catalytic for simplicity. I am an hour and a half outside of Edmonton. What would you suggest would be ideal for heating this space. The alcove is a 52x16 heat shield surround and 90" floor to drywall, just so you know what I have to work with.
 
My observations over the years are woodcook stoves in most homes are decorations more than appliances. The concept sounds good but for most its just too much of PITA. Spacebus seems to be the exception. Therefore, if you really want a cookstove, build a big Hearth and spot a small cookstove next to woodstove. I suggest an older Jotul 404 if you can find one. Its can be cookstove with oven but takes up half the room.
 
My observations over the years are woodcook stoves in most homes are decorations more than appliances. The concept sounds good but for most its just too much of PITA. Spacebus seems to be the exception. Therefore, if you really want a cookstove, build a big Hearth and spot a small cookstove next to woodstove. I suggest an older Jotul 404 if you can find one. Its can be cookstove with oven but takes up half the room.
We have probably 20 customers who use theirs all winter. And a few year round
 
It is well insulated. R30 walls, R40 floor, R60 ceiling, triple pane windows. I agree though, I am already over 2cf and running hard at -20. The main reason for the question was to ensure I don't sacrifice the heating capablities for the novalty of a cookstove. The furnace is always a backup option, but I have an endless supply of free wood on the property. I used 20% of the propane tank in the month before the stove was installed and 5% in the 2 months since. Before moving into this home (same property) we were going through a propane tank a year. Dryer, stove and hot water are gas. Cost is roughly $600 a year, so I will never see the benefit of $5000 to install NG if I get the stove sizing right.

I just installed a 6 inch flue so I would rather not upgrade to 8". I think I would prefer not to go catalytic for simplicity. I am an hour and a half outside of Edmonton. What would you suggest would be ideal for heating this space. The alcove is a 52x16 heat shield surround and 90" floor to drywall, just so you know what I have to work with.

If you did want to try a catalytic a BK Princess would probably be about right, you have a fair bit of insulation and may take advantage of the lower burn rates.

Otherwise I'm biased on the non-cats, I like the Pacific Energy Summit as a workhorse stove, and believe it would suit your needs well.
SBI also makes a 3.3cuft stove (Osburn 3300, Drolet Austral, Drolet Myriad, Drolet Legend, Enerzone Solution 3.3) same firebox just different aesthetics.

There are other options as well, I'm sure someone else will come along with those, but these are the ones I'm most familiar with.

As far as clearances for what will work in your alcove I'm not sure, I'm not familiar with calculating clearance reductions with heatshields.
 
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The wood stove is 12 feet from the kitchen island, 20 feet from the stove. I would likely simmer stock on the stove, which I make often, and reheat food instead of preheating the oven. Buns in the oven every once in awhile.

Honestly the cookstove is romantic/idealistic. The reality is I am busy, I work alot. I rarely have time for baking. Will I use it alot? Not likely. I am hoping I am surprised at how much it will be used, but will I appreciate it when the power is out? You bet. Our cooktop is gas, but oven is electric, and it is nearly imposible to find a gas oven that does not require significant power these days.
I asked because this is the way we use the Alderlea. The swing-away trivets make it great for all kinds of cooking at all temps including simmering and dough rising. It's available in 3cu ft size as the T6.
 
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Our house is about half the the square footage of you and we are using a wood cookstove as our primary cooking appliance for six months out of the year, and occasional use in cooler spring and fall weather. I think we burned into June this year, but definitely not every day. Our cookstove also preheats our domestic hot water. In your house I think the stove you already have combined with a cookstove would be plenty. Both of our stoves together are just over 3 cubic feet of capacity, you would be looking at a bit over 4 cubic feet combined. This year has been so mild I still haven't lit our "heat" stove. Today and yesterday were fairly cold, but we didn't feel like moving the stuff from around the Morso and just kept the cookstove going all day. When it's mild or the Morso is handling heating duties usually I just light the cookstove two or three times a day rather than keep it going.

A cookstove, no matter the efficiency, won't heat the house as well as a normal wood stove. The heat output will be noticeably softer and at least half of the energy is going into the oven, and a lot of that heat is in turn lost to the flue when the fire goes out.
 
I wonder if Alderlea with swing away trivets could be better option for just plain cooking, not baking, than even many of the upright oven above or below cookstoves, heating aside. We have had a cookstove for many many years. For cooking I need to be able to regulate, often fine tune the heat under a pot or pan. For our traditional cookstoves this mostly means moving pots and pans around on the comparatively large cooking surface instead of turning a non woodstove knob to get just the heat you need. I can’t say from experience but is hard to see how you get that on the taller narrow cookstoves. If I’m off on this last, I’ll be glad learn from others’ experience. In any case looking at a picture of the Alderlea it seems to me the clever swinging trivets would give good ability to vary the heat and provide some satisfying cooking ability.

Our first cookstove was an Empress Atlantic with a tiny firebox by todays cookstove standard and a roomy enough oven where my wife baked countless loaves of bread for the family. We had a huge round Sears wood furnace that provided the serious heat for our 2000 ft2 house. They were a fine combination for us. Abstovehunter, sounds like you are moving past it but for someone both planning to get a cookstove but needing greater heat I think a smaller cooker, maybe not the beautiful Rosa XXL, and a whole house capable stove could be ideal.
 
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If you did want to try a catalytic a BK Princess would probably be about right, you have a fair bit of insulation and may take advantage of the lower burn rates.

Otherwise I'm biased on the non-cats, I like the Pacific Energy Summit as a workhorse stove, and believe it would suit your needs well.
SBI also makes a 3.3cuft stove (Osburn 3300, Drolet Austral, Drolet Myriad, Drolet Legend, Enerzone Solution 3.3) same firebox just different aesthetics.

There are other options as well, I'm sure someone else will come along with those, but these are the ones I'm most familiar with.

As far as clearances for what will work in your alcove I'm not sure, I'm not familiar with calculating clearance reductions with heatshields.
Thanks for the insight. The summit is a nice looking stove. The heatshield reduces clearances to 1/3. 18" side clearance is reduced to 6 inches with shielding.
 
I asked because this is the way we use the Alderlea. The swing-away trivets make it great for all kinds of cooking at all temps including simmering and dough rising. It's available in 3cu ft size as the T6.
Thank you for this. I was completely unaware of this type of stove. It may be a practical compromise. I found a propane cookstove with spark ignition oven that will work without power so perhaps the two together will give me the heating and backup options I am looking for.
 
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