Heats How Many Square Feet?

[MovingOffGrid]

I have a PE Summit and can attest to the fact that it will heat my 2 story 2500 sq. ft. home quite well, even in sub-zero temps, but requires quite frequent re-loads when I need to really crank out the BTU's. The Summit is rated as capable up to 3000 sq. ft in the original brochure, however I note that they no longer post this figure on their website.

NON Cat P.E. Summit
Room Size 3000 sq. ft. (from original brochure)
Burn Time (max.)10 hrs.
Firebox Size 3.0 cu.ft.
Heat Output Cord Wood 99,000 BTU
(broken link removed to http://pacificenergy.net/products/wood/stoves/summit/)

I am looking at the new Hybrid/Cat stoves (I'm considering a new stove for longer burn times than my Summit provides) and am trying to get my head around why the Large 3500 and Very Large 5100 Regency Cat/Hybrid stoves suggest 2250 sq. ft heating capability, versus the Regency F3100 non cat stove is rated at 3500 sq. ft., which is about the same capacity as my Summit?

QUESTION:
Will I be sacrificing the sheer power/ max output heating strength when it gets very cold, in order to gain low consistent, loooonger burn times, if I make the switch to a large Cat/Hybrid stove?

NON Cat Regency 3100
Room Size 3500 sq. ft.
Burn Time up to 10 hrs
Firebox Capacity 2.9 cu. ft.
Maximum BTU 80,000
http://regency-fire.com/Products/Wood/Wood-Stoves/F3100.aspx

Regency Cat/Hybrid 3500
Room Size 2250 sq. ft.
Burn Time 24+ hrs
Firebox Capacity 3.0 cu. ft.
Maximum BTU 75,000
http://regency-fire.com/Products/Wood/Wood-Stoves/F3500.aspx

Regency Cat/Hybrid 5100
Room Size 2250 sq. ft.
Burn Time 30+ hrs
Firebox Capacity 4.42 cu. ft.
Maximum BTU 80,000
http://regency-fire.com/Products/Wood/Wood-Stoves/F5100.aspx

FWIW, Blaze King's claimed square footage heating capacity looks more promising but no sign if the max claimed BTU is up to the Summit's level.

Blaze King, King
Heats 1,500 – 3,000 Square Feet
40 Hour Low Burn Times
4.32 Cubic Foot Firebox
51,582 BTU's/h constant output for 12 hours (they seem to not provide a Max BTU output)
(broken link removed to http://www.blazeking.com/EN/wood-stoves.html)

 

[jeff_t]

Take manufacturer's BTU ratings for what you want. Those ratings are max output, which you might see for a short period of time, or maybe not. Square footage ratings are equally worthless.

How well a stove heats your home depends a lot of factors. Layout, insulation, air sealing, to name a few.

How frequent is frequent? How dry is your wood? What kinds of wood are you burning?

I load my King every 12 hours or so when I need the max. The 4.3 cu ft firebox is pretty honest. I've never measured it, but I bet 4 cu ft is useable. The thing holds a ton of wood. I'm heating a 1600ish sq ft ranch built in the early 70s, with plenty of drafts and marginal insulation. Combined with big north and west exposure in the middle of wide open farm country, and the stove is run at its limits at times.

My sister's King is in a 2600 sq ft two story house that is newer, tighter, and better insulated than mine. While it is much easier to heat than my house, the stove still struggles in windy, sub zero weather.

 

[MovingOffGrid]

yup- agree with your 'take all manufacturers suggestions with grain of salt' suggestion.

Frequent loading to achieve max BTU is about every 4 hours in cold weather - then I load her up at night and hope to squeek out a 10 hour burn/glow by the morning.

Been heating with wood full time for over 30 years - part time a lot longer before that ;-)
2 year well seasoned dry wood - Maple/Alder/Fir/Birch
R40 ceiling - R20 walls - central chimney .... it's all good.

.... just wondering if these "2250" sq ft Regency BIG Hybrid models (2250 doesn't sound very big to me) can actually compete when serious heat output required, or are they only any good when you don't need major BTU's and are content to let it glide?

 

[bholler]

I just installed one today and it is huge. Havn't seen one burning yet but it looks like it will put out some serious heat

 

[BrotherBart]

BTUs are btus. Cats and hybrids are great for low and slow and can be cranked up for max heat. But figure on loading them just as often when kicking them in really cold weather. They can't get more out of a stick of wood than was in there to begin with.

 

[MovingOffGrid]

I just installed one today and it is huge. Havn't seen one burning yet but it looks like it will put out some serious heat

ya that's what I thought when I saw it at my local dealer - it's one BIG mother - but then I saw the 'heats 2250 sq ft. ' bit and started scratching my head.
At first I put it down to them being modest/understated in comparison to others, until I saw what they rate their smaller 2.9 cu.ft Regency 3100 Non cat stove at: 3500 Sq ft heat

 

[MovingOffGrid]

BTUs are btus. Cats and hybrids are great for low and slow and can be cranked up for max heat. But figure on loading them just as often when kicking them in really cold weather. They can't get more out of a stick of wood than was in there to begin with.

makes sense, but for the size of this monster stove, would you not think they would rate it at least as well as their 3100 model which is rated at 3500 sq ft capability?

That's what has me wondering if the large cat stoves are not meant to be run hard and/or the Cat can't stand that kind of BTU's without damaging it?

2250 sq. ft is what most middle of the road sized non-cat stoves are rated at. A 4.42 cu. ft. firebox with huge radiant shell like the 5100 has, and rated at 2250 sq ft capacity, sure looks anemic on paper.

Just wondering out loud!

 

[Grisu]

Do a forum search. I think we already had some threads about the 5100. I think the gist of it was that it puts out some serious heat when run correctly but burn times are not as long as Regency claims. Are you prepared to change the flue to 8"? Maybe a second, smaller stove somewhere else would be a more feasible option. Could be run only when needed. For other XL stoves look at:
Buck 91
Kuma Sequoia
Hearthstone Equinox

What are you burning; hardwoods or softwoods?

 

[Bigg_Redd]

But figure on loading them just as often when kicking them in really cold weather.

Indeed. They can stretch out the release of BTUs but they cannot create them.

 

[MovingOffGrid]

My sister's King is in a 2600 sq ft two story house that is newer, tighter, and better insulated than mine. While it is much easier to heat than my house, the stove still struggles in windy, sub zero weather.

That's what I need to hear... sounds like I may not be better off changing out my non-cat stove. Cost of going to 8" chimney and no real improvement in depth of winter max performance leans me towards staying with non-cat and looking at better ways to circulate the air into upper floor.

 

[BrotherBart]

I am just waiting patiently to see what happens to cat life after an extended period of cranking the hybrids. With the secondary combustion blasting and the heat being sucked into, not made in the cat. Who knows, it may make the cats last longer. Or not. Gonna be interesting to see over real-world time.

 

[8ball]

That's what I need to hear... sounds like I may not be better off changing out my non-cat stove. Cost of going to 8" chimney and no real improvement in depth of winter max performance leans me towards staying with non-cat and looking at better ways to circulate the air into upper floor.

Check out the 6" F3500 pretty nice from Regency as well

 

[MovingOffGrid]

Check out the 6" F3500 pretty nice from Regency as well

Ya I've been looking at the F3500 6" as a possible replacement for my Summit without having to go to an 8" chimney, but I'm concerned that they also say a measly 2250 sq ft on that model as well. Sounds pretty anemic compared to their 3500 sq ft claim on their Regency 3100 non cat stove.

One thing I don't have to do with my summit is baby it. it will run hot and hard as long as the wood lasts, and in the dead of winter, it pumps out the heat. I'd just like to have to load it less frequently and if the Cat stoves won't run as hard, or there's a concern the cat's may wear more with high BTU's, that won't work as I had hoped.

 

[MovingOffGrid]

What are you burning; hardwoods or softwoods?

as mentioned above . . . I burn Maple,Alder,Birch, Fir - 2 year seasoned.
Prefer Maple in dead of winter but take what I can get.

 

[8ball]

Ya I've been looking at the F3500 6" as a possible replacement for my Summit without having to go to an 8" chimney, but I'm concerned that they also say a measly 2250 sq ft on that model as well. Sounds pretty anemic compared to their 3500 sq ft claim on their Regency 3100 non cat stove.

One thing I don't have to do with my summit is baby it. it will run hot and hard as long as the wood lasts, and in the dead of winter, it pumps out the heat. I'd just like to have to load it less frequently and if the Cat stoves won't run as hard, or there's a concern the cat's may wear more with high BTU's, that won't work as I had hoped.

The F3500 is a nice stove,so is the 3100.The 3100 delivers it's heat short and sweet , 6 hrs of flame max, the F3500 gives18,same btu's slowly and evenly.Turn up the 3500 only get 12 hrs but somewhat hotter out put.Get an Airmate heats 50% more sq ft
Cheers

 

[Grisu]

as mentioned above . . . I burn Maple,Alder,Birch, Fir - 2 year seasoned.
Prefer Maple in dead of winter but take what I can get.

That's what I thought; you lack a bit the high BTU hardwoods. Still, how can you load the Summit every 4 hours? With the maple you should still have a lot of coals left that you can put in only a few splits. What do you do with the coals during the reload? Do you have a stovetop thermometer? What temps are you running the stove at usually?

 

[begreen]

Ya I've been looking at the F3500 6" as a possible replacement for my Summit without having to go to an 8" chimney, but I'm concerned that they also say a measly 2250 sq ft on that model as well. Sounds pretty anemic compared to their 3500 sq ft claim on their Regency 3100 non cat stove.

One thing I don't have to do with my summit is baby it. it will run hot and hard as long as the wood lasts, and in the dead of winter, it pumps out the heat. I'd just like to have to load it less frequently and if the Cat stoves won't run as hard, or there's a concern the cat's may wear more with high BTU's, that won't work as I had hoped.

I don't think you are going to see much change from the Summit with a new stove unless you greatly increase the firebox capacity. If you do, the Blaze King King is worth considering. When did you get your Summit? Does it have the new style EBT on the secondary intake? Also, what has been done to reduce heat loss in the house?

 

[Grisu]

.Get an Airmate heats 50% more sq ft

It does not. It spreads the same amount of heat over a larger area lowering the average temps in all rooms.

 

[Seanm]

My super has a 2 cf fire box and your Summit has a 3 and I easily get longer than a 4 hour burn time on a 3/4 load of Lodgepole Pine even when its cold out which is often here. On a full load of Larch at 11 pm I have coals at 9 am that will catch new splits. I noticed you mentioned above that in cold weather for max btus you get 4 hours but are you opening up more draft once your stove top temps drop reducing your burn times or are you saying you only get 4 hours at max btus?

 

[MovingOffGrid]

My super has a 2 cf fire box and your Summit has a 3 and I easily get longer than a 4 hour burn time on a 3/4 load of Lodgepole Pine even when its cold out which is often here. On a full load of Larch at 11 pm I have coals at 9 am that will catch new splits. I noticed you mentioned above that in cold weather for max btus you get 4 hours but are you opening up more draft once your stove top temps drop reducing your burn times or are you saying you only get 4 hours at max btus?

4 hours at MAX BTU's when it;s cold out and I'm pushing her.

That's what I thought; you lack a bit the high BTU hardwoods. Still, how can you load the Summit every 4 hours? With the maple you should still have a lot of coals left that you can put in only a few splits. What do you do with the coals during the reload? Do you have a stovetop thermometer? What temps are you running the stove at usually?

Maple, Alder, Birch and Fir are the west coast woods we have ... Maple burns the longest but I hear it's nothing like oak or other eastern hardwood.

I use a single wall stove thermometer and burn in the upper range of the sweet spot. In the dead of winter when it's below freezing for some time, as ashes build up after some successive burns, I throw a couple small splits on the top and open up the stove even more to burn down the coal bed as the night approaches, then stuff her as full as I am confident she can handle it with the hardest splits available, and dampen down to keep her idling at low end of sweet spot range overnight. Always have enough coals after 8 hours to spark some fresh splits, but it sure would be nice to get the same max temps and also the longer burn times.

In shoulder season, I can burn it slower with less BTU's, but either way I've got this stove dialed in pretty well on my chimney after 5 winters.

 

[Grisu]

Where is the thermometer located: On the stovetop somewhere central or on your single wall pipe (how high?)?

What temperature is the "sweet spot"? About how much do you leave the air open when you want to "push" the stove? How much for an overnight burn?

I am asking because I have the Summit's little brother, the Super. When I fill it up with dry white pine I get the stovetop easily to 700 F and the load burns down in about 4 hours. 700 F is about the highest I like it to reach. When I reload the temp is still ~500 F. If I would try to push the stove even more I would risk an overfire.

 

[MovingOffGrid]

Where is the thermometer located: On the stovetop somewhere central or on your single wall pipe (how high?)?

What temperature is the "sweet spot"? About how much do you leave the air open when you want to "push" the stove? How much for an overnight burn?

I am asking because I have the Summit's little brother, the Super. When I fill it up with dry white pine I get the stovetop easily to 700 F and the load burns down in about 4 hours. 700 F is about the highest I like it to reach. When I reload the temp is still ~500 F. If I would try to push the stove even more I would risk an overfire.

Sweet spot is 300 to 570 F on stovepipe thermometer about 18" to 20" up the pipe from the stove. 300F is where the secondary burn kicks in. - I push it to upper end (500 to 570 F) when I need max BTU. No worries, I've had it into the 600+ range on brief occasions and never seen a glow.

3 to 4 hour burns are the norm for me as well if I'm running it with 1/2 to 3/4 full and about mid range temps (400-450F). Secondary burn (>300F) will only last for about maybe 60% of that period however, as she gradually uses up the wood. Certainly a Cat stove would do better at this at lower temps, but can it manage the higher BTU's when really needed over time - that's my concern?

 

[Grisu]

I suggest getting a second (stovetop) thermometer and placing it in the center of the stovetop; probably just in front of the flue collar will be the hottest spot. Adjust the air as low as possible but while you still get the stovetop between 600 F and 700 F. That will be the setting when you get the most amount of heat with the longest burn time. Right now, when you open the air more to get the flue thermometer above 500 F you are actually sending more heat up the flue. Best would be flue thermometer between 300 F to 400 F and stovetop 600 F to 700 F.

 

[MovingOffGrid]

I suggest getting a second (stovetop) thermometer and placing it in the center of the stovetop; probably just in front of the flue collar will be the hottest spot. Adjust the air as low as possible but while you still get the stovetop between 600 F and 700 F. That will be the setting when you get the most amount of heat with the longest burn time. Right now, when you open the air more to get the flue thermometer above 500 F you are actually sending more heat up the flue. Best would be flue thermometer between 300 F to 400 F and stovetop 600 F to 700 F.

Thanks for your thoughts ....
The colder it gets the more I can throttle her down and the hotter she runs. Summit is a beast when temps drop and all 28' of chimney starts sucking.
I'm all ears on the F3500 with same size firebox, especially for longer burn times in shoulder season, but not sure it would keep up to the Summit at peak output.

 

[MovingOffGrid]

I don't think you are going to see much change from the Summit with a new stove unless you greatly increase the firebox capacity. If you do, the Blaze King King is worth considering. When did you get your Summit? Does it have the new style EBT on the secondary intake? Also, what has been done to reduce heat loss in the house?

Got Summit in 2009 and it has the EBT. I have had a peek at the EBT opening during various intervals and it doesn't seem to do very much or change.

House is well built R20 in 2x6 walls, ceiling is R40
Double glazed windows - fairly easy to heat home.

After hearing in this thread about the BlazeKing King barely keeping up on a 2600 sq. ft home when the temps dropped below freezing, I'm thinking less about investing in another stove now.