Max heat

[Doc C]

I have been running my BK Boxer wide open and still having trouble keeping my 1500SF well insulated single level house above about 64 degrees

I’m wondering if I’m sending a bunch of heat up the chimney and maybe I’d be better off turning it down just a little bit?

Any thoughts?

 

[stoveliker]

Many questions before thinking about an answer...

So even the room that the stove is in is not going above 64 F? If the stove room IS getting warm enough, what is the lay-out of the home (a sketch would help).

How long have you had the BK?

What is your chimney set up? Mostly, how tall is it?

Do you have a flue probe thermometer?

What is the outside temperature?

Are all gaskets still okay? (Dollar bill test)

What is your wood moisture content?

My experience (BK, but not a boxer) is that the higher the thermostat the higher the heat output into the room (even if more heat goes up the flue too).

 

[Doc C]

Many questions before thinking about an answer...

So even the room that the stove is in is not going above 64 F? If the stove room IS getting warm enough, what is the lay-out of the home (a sketch would help).

How long have you had the BK?

What is your chimney set up? Mostly, how tall is it?

Do you have a flue probe thermometer?

What is the outside temperature?

Are all gaskets still okay? (Dollar bill test)

What is your wood moisture content?

My experience (BK, but not a boxer) is that the higher the thermostat the higher the heat output into the room (even if more heat goes up the flue too).

Brand new stove last winter but only got it about Feb so not much time driving it

The room it’s in will get to about 70ish pretty easy but my house is wide open and I have a big wall Mount fan pushing the heat towards the rest of the house

Chimney is close to 20’ tall and double wall until the roof then it’s triple wall

No probe

All gaskets are fine

Freshly split and test I’m between 14-18% and it’s 100% Doug fir which is the best wood available in my area

 

[stoveliker]

Wood sounds great.

Moving the heat works much better if you have a fan on the ground, pushing cold air towards the stove room. It'll be replaced by warmer air from the stove room. This fan should be running on low so you don't mix too much warm and cold air, that would hinder the flow.

20' should be ok (though I hear that triple wall is not ideal - but I was asking about the chimney to see if you had too much draft that might suck out heat; triple wall might actually decrease the flue gas temps, which is not ideal for a BK, but should not be the cause of the issue you see, imo.)

Does the stove room have a high ceiling? Do you have a ceiling fan to push down the heat?
70s is rather low for a BK running high. My BK is in an 825 sq ft basement, and I easily get it up to the high 80s, even without running it hard.

 

[Doc C]

I have a box fan on low that pushes the air towards the wood stove room and then a big wall Mount fan up high that pushes the heat out of the wood stove room

I believe it’s triple wall above the roof because it’s silver but I may be wrong. Installer was the installer for the dealer that sells BK stoves so I hope it did it the best way

I have 8’ ceilings in the whole house.

 

[Doc C]

My room that the stove is in is about 400SF living room roughly but it’s really open to the rest of the house

 

[Doc C]

 

[begreen]

Is this the Boxer 20 or 30? Was the Englander 30NC previously installed there? How did that do?

 

[Doc C]

Is this the Boxer 20 or 30? Was the Englander 30NC previously installed there? How did that do?

No englander in this house. This was a new install so no stove was there before

I think it’s the Boxer 24??? Not sure what the 20 or 30 is?

 

[Corey]

Well, "wide open" is typically not the way to get the the most heat. It's generally just a good way to use up the most wood. With air 'wide open' all your heat goes up the flue before it can heat the stove, room, etc.

I would say, experiment with getting a good fire going, then as you start to shut down the air, you should see stove temps climb. Shut down the air a bit more and the temps climb a bit more. Do this in small increments over 10-15 minutes at each adjustment. The stove should get hotter and hotter as you close the air down. At some point, the stove temp will start to drop - that is the 'control point' where you actually burn efficiently and you can adjust the air slightly up or down to get more or less heat.

 

[stoveliker]

Boxer is only a 24. No 20 or 30.

I am a bit stumped; wood seems good, chimney is likely not the cause. Gaskets said to be good.
The stove should do well in the space.

Regardless of the efficient way Corey is explaining (which is in principle correct), the way the BK works in my place is that if I turn up the thermostat, I get more heat out. If you run it turned up high, you should cook yourself out of the room (high 80s) easily, if it's well insulated as you say. @BKVP says that the testing data show that the efficiency is actually not varying much in the range that the thermostat allows. So while more heat goes up the flue when burning higher, the *fraction* of BTUs produced that goes up the flue remains more or less the same.

The only thing I would suggest is to add a flue probe. I have a Condar. This will tell you how much heat goes up the flue. It should read 450-600 F when running high.

 

[begreen]

No englander in this house. This was a new install so no stove was there before

I think it’s the Boxer 24??? Not sure what the 20 or 30 is?

Got it. The Englander 30 is still listed in the signature line.

What are the outdoor temperatures? Is the catalyst thermometer well into the active range? How tall is the flue system on the stove from stovetop to chimney cap?

The Boxer 24 should be putting out about 30,000 BTUs steady on high. That should be able to heat a well-insulated, 1500 sq ft house unless there is an unaccounted-for heat loss in the house that needs reducing with better sealing and insulation. (Too many windows?) Another possibility is that the thermostat on the stove is not working properly. IIRC, that happened several years back on some BK stoves.

As a test, turn off the large wall mount fan and just run the box fan for a bit.

 

[Doc C]

Got it. The Englander 30 is still listed in the signature line.

What are the outdoor temperatures? Is the catalyst thermometer well into the active range? How tall is the flue system on the stove from stovetop to chimney cap?

The Boxer 24 should be putting out about 30,000 BTUs steady on high. That should be able to heat a well-insulated, 1500 sq ft house unless there is an unaccounted-for heat loss in the house that needs reducing with better sealing and insulation. (Too many windows?) Another possibility is that the thermostat on the stove is not working properly. IIRC, that happened several years back on some BK stoves.

As a test, turn off the large wall mount fan and just run the box fan for a bit.

Outdoor temps are running between 5f to 20f

Cat is well into the active range

I have not measured but I’d say 16-20’ roughly

Proper amount of windows including 1 in each bedroom, 1 brand new 4x8 in the living room plus a small 2x2 window on the opposite wall, a French door leading to a deck in the kitchen and then 1 window in the dining room, 1 bathroom has a small window

I can get the thermostat just past the hottest point on it with it wide open and the cat engaged.

I will try to turn off the wall mount fan

Do you have any other ideas

 

[stoveliker]

The thermometer on top is not indicative of the heat output, it tells you the cat temperature. And that could in fact be lower when the stove is cranking out BTUs; when running high a larger fraction of heat is generated by the primary fire, and the cat adds a bit by cleaning up the gases.

 

[Doc C]

The thermometer on top is not indicative of the heat output, it tells you the cat temperature. And that could in fact be lower when the stove is cranking out BTUs; when running high a larger fraction of heat is generated by the primary fire, and the cat adds a bit by cleaning up the gases.

Thank you. So what does that do for this situation?

 

[stoveliker]

Not much; hence my suggestion for a flue probe. The thermometer on the stove is only meant to provide info on whether to engage the cat or not.

Begreen's question about whether the thermostat works as it should is on-point as well. Especially if the pic you posted was with the thermostat wide open (as I would do if the room temperatuer is 64 and I wanted it to be 70 F) - there should be flames visible (at least, there would be in my stove, with that amount of fuel left).

So, when you have flame, can you see that moving the thermostat changes the flames?

If you decrease the thermostat (right until you hear a "clang"), do the flames die down? And after a while, do they come up again?

I hope others will chime in too.

 

[Doc C]

Not much; hence my suggestion for a flue probe. The thermometer on the stove is only meant to provide info on whether to engage the cat or not.

Begreen's question about whether the thermostat works as it should is on-point as well. Especially if the pic you posted was with the thermostat wide open (as I would do if the room temperatuer is 64 and I wanted it to be 70 F) - there should be flames visible (at least, there would be in my stove, with that amount of fuel left).

So, when you have flame, can you see that moving the thermostat changes the flames?

If you decrease the thermostat (right until you hear a "clang"), do the flames die down? And after a while, do they come up again?

I hope others will chime in too.

If I close the thermostat down until it makes the noise the flames will die out but they never come back. But the whole load will burn just fine I just won’t get flames again unless I open the thermostat back up a little

When the thermostat is wide open I have flames. Not sure why they didn’t show in that pic but they were either there or I was down to coals…not sure

 

[BKVP]

Sounds like thermostat is working as intended.

 

[stoveliker]

@BKVP:
I'm not sure that it sounds like it is working as intended; the knob certainly moves the flap (or whatever the correct terminology is), but the observations noted above would also be consistent with a thermostat that does not do anything, other than being a manual flapper positioner - i.e. is the bimetal actually moving the flap?

If I run hot (high), then I dial down until I hear the sound (which is not all the way down because I was running hot), let the flames die out. But after a while, the flames come back a little - I presume because the flap opens a bit as the room cools down to the new setting, and it needs a bit more BTUs to maintain that new setting.

Granted this is quite dependent on room, install, etc. but the observations by the OP are also consistent with just a flap that one moves manually and is static otherwise.

 

[moresnow]

Are you running completely full loads? Are you utilizing the stove blowers? Can you get an accurate length of pipe from stove top to termination?

 

[Doc C]

Are you running completely full loads? Are you utilizing the stove blowers? Can you get an accurate length of pipe from stove top to termination?

Yes completely full loads

I’m not climbing on my metal roof with snow on it right now but extending a tape measure and measure from my fascia to as accurately as I can get to the cap plus the inside part of my house I’m coming up with 17 1/2 feet. I would say this is accurate to within 6 inches

 

[Doc C]

House is 2x6 walls with from the inside out, 5/8” drywall, spray foam. 1/4” melamine type product, Osb, t1/11 siding

Windows are new and good quality vinyl, exterior doors are good quality and new

Attic is blow in insulation about 10-12” deep depending on the area

Crawl space is sealed with spray foam on the walls and plastic on the floor. Crawl space is always really close to the temp of the house.

House is exactly 1508 square feet. It was just over 1300sf when we bought it and we gutted it, added about 200SF, air sealed everything and remodeled it.

 

[Doc C]

One other thing I should mention that may be relevant

If I turn the dial below half way the fire goes out and I’m left with unburnt logs in the morning. I’m getting good draft and even cracking a window doesn’t do anything for keeping the fire going at less then half on the thermostat

 

[kennyp2339]

I wonder if your t stat is calibrated correctly, 1/2 way and you get a stall doesnt make sense unless your running a short stack w/ poor draft, do you get any smoke spillage when you open the loading door with the by-pass open?

 

[Doc C]

I wonder if your t stat is calibrated correctly, 1/2 way and you get a stall doesnt make sense unless your running a short stack w/ poor draft, do you get any smoke spillage when you open the loading door with the by-pass open?

No visible smoke in the house at all when the door is opened. I’ve had draft issues in other houses and this does not seem to have a problem with draft at all.