New stove vs old stove

[old greybeard]

So like a fool I took out my old 1970's airtight and bought a Lopi 1750. Its at my cabin in northern Pa. On top of a mountain. Cabin is 24x28. 10 ft walls, open ceiling, on piers. One big room with open loft. Maybe 1000 sq feet if you count the loft. R13 in all walls and floor. R10 double sided reflective in 2/3 of the ceiling, R12 in the other 1/3. Double pane windows. We do have some air leakage at floor level. But snow does not melt from tin roof.
My old stove kept this place toasty hot, even on 2 degree or negative days it stayed warm.
This new stove, with temps in the 30's, keeps it low 70's, when being babied and fed. Forget overnight, as soon as the secondaries stop burning after a few hours the temp drops, even with chunks and coals. During the day no issue, open the air, burn them down, reload. Today the inside was 71, had a hot stove, put in 3 nice splits, backed the air down till she settled down and went hunting. 31 degrees and snowing, little wind. After a hour the temp dropped to 68, with secondaries still lit and a nice fire. WT?!, temp dropping with a good fire.
This stove is sized for a medium to large house, 1200 to 2000 sq feet. Shouldn't it be able to keep it warmer with a good burn with out the blower running?
Using 18' inside double wall stainless with a factory chimney. Pipe dosen't even radiate hardly any heat. Loft is no warmer than downstairs, with the old stove it was HOT in the loft.
We're screwed when it hits lower temps and the wind howls.
Am I expecting to much? Burning nice dry sugar maple, 12-15%. Same as always.
I really regret buying this thing. looking for any advice to increase heat. Changing wood type is not a option, nor should it be needed, maple is a fine wood to burn.

 

[bholler]

So like a fool I took out my old 1970's airtight and bought a Lopi 1750. Its at my cabin in northern Pa. On top of a mountain. Cabin is 24x28. 10 ft walls, open ceiling, on piers. One big room with open loft. Maybe 1000 sq feet if you count the loft. R13 in all walls and floor. R10 double sided reflective in 2/3 of the ceiling, R12 in the other 1/3. Double pane windows. We do have some air leakage at floor level. But snow does not melt from tin roof.
My old stove kept this place toasty hot, even on 2 degree or negative days it stayed warm.
This new stove, with temps in the 30's, keeps it low 70's, when being babied and fed. Forget overnight, as soon as the secondaries stop burning after a few hours the temp drops, even with chunks and coals. During the day no issue, open the air, burn them down, reload. Today the inside was 71, had a hot stove, put in 3 nice splits, backed the air down till she settled down and went hunting. 31 degrees and snowing, little wind. After a hour the temp dropped to 68, with secondaries still lit and a nice fire. WT?!, temp dropping with a good fire.
This stove is sized for a medium to large house, 1200 to 2000 sq feet. Shouldn't it be able to keep it warmer with a good burn with out the blower running?
Using 18' inside double wall stainless with a factory chimney. Pipe dosen't even radiate hardly any heat. Loft is no warmer than downstairs, with the old stove it was HOT in the loft.
We're screwed when it hits lower temps and the wind howls.
Am I expecting to much? Burning nice dry sugar maple, 12-15%. Same as always.
I really regret buying this thing. looking for any advice to increase heat. Changing wood type is not a option, nor should it be needed, maple is a fine wood to burn.

The lopi is rated to heat 1200 to 2000 sqft with 8' ceilings you are atleast equal to that in cubic feet. How are you running the stove? I have never burnt a lopi but they are very similar to the regency that i used the last few years. And with it i got the highest heatoutput at about 3/4 closed. What are your stove top and pipe temps?

 

[Jan Pijpelink]

The lopi is rated to heat 1200 to 2000 sqft with 8' ceilings you are atleast equal to that in cubic feet. How are you running the stove? I have never burnt a lopi but they are very similar to the regency that i used the last few years. And with it i got the highest heat output at about 3/4 closed. What are your stove top and pipe temps?

I have the Avalon Rainier, which has similar specs as the 1750, with a slightly smaller fire box (1.9 cft). It is in a fireplace, external chimney at the lower level of a 2400 sft raised ranch. With outside temps of low 30's running dry oak 24/7 I can keep the whole house "toasty" at 78-80 F, using a standing fan at the opposite wall of the stove. Also using ceiling fans at the upper level; in winter mode. Usually at 3/4-5/16 air open I can keep stove top temp at 500-550. I reload once every 6 hours and stuff the stove as full as possible for an overnight burn. Reloading at 1 AM, I have more than enough coals at 8 AM for a new load without using fire starters or paper. Ceilings are 8 ft.

 

[old greybeard]

Double wall stainless so don't monitor pipe. Stove top with condar, stove works best at 650-675, gets there very fast. I get secondaries real quick. I can close the air down to where the primary is just open the slightest crack and it maintains 650 for a hour or two. By slightest crack I mean looking underneath at the air input visually it has just a tiny bit showing open.
3/4 closed with a full load she will overfire. Not getting any air leakage, when shut all the way or with no open showing it shuts down.
Disagree with you on the size, my home is only 2000 square feet, much harder to heat with closed off spaces and cathedral ceilings. The footprint of the cabin is tiny in comparison, plus its all open. And no extra heat is felt in the loft, as stated with the old stove it was over 90 degrees up there when it was cooking.

 

[old greybeard]

btw this was installed professionally after a site survey. Still waiting to hear from them. My impressions so far are that i'm fine during the shoulder seasons, actually better than the old stove. But I need something to keep my wife lightly clothed in the cold dead of winter.
I am getting great draft, could a pipe damper help it radiate heat?

 

[bholler]

Double wall stainless so don't monitor pipe. Stove top with condar, stove works best at 650-675, gets there very fast. I get secondaries real quick. I can close the air down to where the primary is just open the slightest crack and it maintains 650 for a hour or two. By slightest crack I mean looking underneath at the air input visually it has just a tiny bit showing open.
3/4 closed with a full load she will overfire. Not getting any air leakage, when shut all the way or with no open showing it shuts down.
Disagree with you on the size, my home is only 2000 square feet, much harder to heat with closed off spaces and cathedral ceilings. The footprint of the cabin is tiny in comparison, plus its all open. And no extra heat is felt in the loft, as stated with the old stove it was over 90 degrees up there when it was cooking.

Sounds like you may need a pipe damper. Are you saying you have class a chimney starting at the stovetop???

 

[old greybeard]

No I have 18' of double wall pipe, the bottom section is a 48" expandable adapter. It terminates at a factory built chimney which is mounted between the purloins on my metal roof. All exposed in the living area.

 

[bholler]

No I have 18' of double wall pipe, the bottom section is a 48" expandable adapter. It terminates at a factory built chimney which is mounted between the purloins on my metal roof.

Ok get a probe thermometer for the pipe and from what you are saying i would say you could use a pipe damper as well.

 

[old greybeard]

Ok get a probe thermometer for the pipe and from what you are saying i would say you could use a pipe damper as well.

Could you explain to me how the pipe temperature can be useful? Thanks

 

[bholler]

Could you explain to me how the pipe temperature can be useful? Thanks

If your pipe temp is to high you are sending to much of your heat out the chimney. Meaning less in the cabin.

 

[old greybeard]

Thanks, logical answer. Right now the pipe never gets very hot externally. Even with the hottest fire I can touch it for a second. Assume heat is rising so fast it doesn't radiate.
Does this mean when the temps are colder outside and the wind is heavy and my draft increases that I'll lose even more heat up the pipe?

 

[bholler]

Thanks, logical answer. Right now the pipe never gets very hot externally. Even with the hottest fire I can touch it for a second. Assume heat is rising so fast it doesn't radiate.
Does this mean when the temps are colder outside and the wind is heavy and my draft increases that I'll lose even more heat up the pipe?

Very possibly which is why i suggested a pipe damper. And double wall wont radiate much of any heat that is by design.

 

[old greybeard]

Very possibly which is why i suggested a pipe damper. And double wall wont radiate much of any heat that is by design.

Installer is coming up during the first week of Buck season with a damper and a temp probe. Thanks for the help.

 

[tcassavaugh]

well....how did it work?

 

[Enplater]

The old stoves really put heat into the room. I have an englander 30 but last season I hooked up an old fisher grandma bear for fun and it really cranks. I think it might use more wood in total with the fisher but it seems to put more heat in the room. I think newer stoves are double wall steel to keep heat inside the firebox instead of transferring heat to the room. 8 hours after loading the fisher I might have coals to reload but with englander there will be plenty of coals with stove temp of 200 or so. I wonder how the fisher would act with a baffle and air tubes?

 

[begreen]

There are still some unshielded steel stove available that are strongly radiant like the old stoves. Most people prefer them with side and rear shields to reduce clearances.

 

[jetsam]

Who moves and installs a grandma bear 'for fun'? Oh, Marines...

 

[Manly]

Reminds me of a couple of years back when I was in our regional stove store purchasing my pellet stove, a man came in who was furious with his sales rep. Couldn’t help but overhear his complaining about the lack of heat output of the new stove he just had them install. The stove they removed was an All Nighter Big Moe. My previous stove was a Mid Moe and I can only imagine how much heat the Big Moe can throw. This gentleman was livid saying they guaranteed the new stove would put out as much or more heat than Big Moe. Not sure what the new stove was, but it’s a huge stove shop that carries most of the major brands. They have a lot of young sales people. I was thinking to myself at the time that is a heck of a promise from a kid who probably never saw an All Nighter in action, or any smoke dragon for that matter. I would never go back to the old stoves, but they did pump out the raw heat. Our mid moe was a bit overpowering for our application. The Jotul 3cb is a better fit, look and more efficient, but no match for raw heat output.

 

[kennyp2339]

I get the radiance of the older stove, but do you think the newer stoves don't radiate as much because of the insulated fire boxes? Extra fire bricks and double jackets?
I'd venture to say that you can (but don't do it) take the course of wall fire brick out of a NC30 and you would have pretty much a Fisher stove with a baffle and secondary re-burn, there the same thickness in steel material.

 

[jetsam]

I would never go back to the old stoves, but they did pump out the raw heat.

My grandmother taught me to gauge stove temperature by putting out all the lights and adjusting the air until the steel was just barely glowing.

This is the same woman who cleaned her fireplace flue with her Christmas tree every year. She'd drag the whole tree across the living room, stuff it up the flue, and light it.... and yes, the fire department was involved twice that I know of over the years.

I am not switching back either, but I sort of miss the old stoves. Throw in whatever you want and stand back!

 

[Ludlow]

Why not use single wall?

 

[bholler]

Why not use single wall?

Because if it is being run correctly there isnt much heat in that pipe to spare. Heat with the stove not the venting systems

 

[jetsam]

I get the radiance of the older stove, but do you think the newer stoves don't radiate as much because of the insulated fire boxes? Extra fire bricks and double jackets?
I'd venture to say that you can (but don't do it) take the course of wall fire brick out of a NC30 and you would have pretty much a Fisher stove with a baffle and secondary re-burn, there the same thickness in steel material.

It seems fairly intuitive to me that any time you insulate a metal stove, be it via an air gap or by actual insulators like firebrick, you're getting less heat transfer. Still, modern stoves manage to get most of the heat out into the room (unless they have an extreme handicap like being covered in soapstone or living inside a fireplace).

That firebrick insulation at the bottom has different benefits in terms of keeping your coal bed toasty, so it's worth the loss of a little firebox-to-room surface area.