Unable to keep the fire running full - Princess32

[Phalynx]

New to the whole wood stove world and having trouble staying warm. We have about 800 sq ft house 1 1/2 story loft with a Princess 32 in the middle. It’s getting really cold outside (-24F) and we’re running it wide open and just can’t keep the place warm. It’s currently 55F in here. House has R21 walls, R30 roof, r35 floor. The stove pipe is about 19’ total length. It is a straight up run and is about 1’ over the ridge. It doesn’t appear to have any draft issues. I almost never have smoke come back in when I open the door. I am mostly burning birch. Moisture is between 14-18%. We are hot loading it a bunch to try and keep the temps up in here but we also get a lot of coaling building up on the bottom until almost level with the bottom of the door. We can get the fire roaring at times where the probe is at 6 o’clock but it usually hands in the 3-4 o’clock range. We are running it wide open. If we turn it down, the fire will go down to right at go/no go zone.

What can I do differently? What am I possibly doing wrong? I need more heat in here. I did let the fire go completely out and clean out the box, I inspected the stove pipe, it looked pretty clean with just a little bit of creosote but mostly clean pipes. I vacuumed the cat which was about 1/2 clogged (probably from burning wet wood at the beginning of the season). The bypass is clean. Let me know if there’s anything else I need to mention?

Thanks

 

[stoveliker]

I think you have too much draft, and heat is sucked up the flue. (And ashes in the cat).
You need a key damper.

Your wood may also be too wet (coals left over).
Are you measuring after letting the wood get up to temp for a day,.then resplitting and measuring on the freshly exposed surface (pins as deep as possible and parallel to the grain,)?

 

[Murray01]

Are you closing the Bypass door and feeling/forcing the “snap” when it closes? I’m assuming you are running the stove as per the owner’s manual?

 

[moresnow]

Factory fans installed and running?

 

[EatenByLimestone]

Is the stove hot enough?

 

[Phalynx]

Your wood may also be too wet (coals left over).
Are you measuring after letting the wood get up to temp for a day,.then resplitting and measuring on the freshly exposed surface (pins as deep as possible and parallel to the grain,)?

I just split some and checked it. They are between 16.8% and 19.9% on the various sticks I split and checked.

Are you closing the Bypass door and feeling/forcing the “snap” when it closes? I’m assuming you are running the stove as per the owner’s manual?

Yes, I can feel the door mechanically lock closed.

Factory fans installed and running?

There are no fans installed and no fresh air intake at this time. We do have 2 stove top fans running. I understood the factory fans to do the exact thing as the stove top.

Is the stove hot enough?

We can get it to 450-500F regularly, but not more for very long.

Also, another issue seems to be that the coals on the front of the stove get oxygen but those in the back don’t. The front glows, the back is very dark to black. You might be able to see in the picture. We don’t have a lot of wood in it at the moment as we’re deciding to empty all the coals or not at the moment.

 

[stoveliker]

Do you have a flue probe?

If your draft is too high, you can get ashes sucked into the cat, clogging it, leading to anemic performance.

Would it burn ok after vacuuming the cat (and taking the pipe off, shining a light back there and seeing that all channels are clear? - taking the cat out you'd need a new gasket to put in t back in).

 

[EatenByLimestone]

You need to run the stove warmer too. The stove isn’t putting out enough btus at 450 to heat the place at those temps. Try it at 650.

Rake the coals forward when you reload. The air hitting them (bright red) will burn them down so they don’t fill up the stove.

If you have a ceiling fan, turn it on to circulate the air.

 

[Phalynx]

Do you have a flue probe?

If your draft is too high, you can get ashes sucked into the cat, clogging it, leading to anemic performance.

Would it burn ok after vacuuming the cat (and taking the pipe off, shining a light back there and seeing that all channels are clear? - taking the cat out you'd need a new gasket to put in t back in).

I don’t have a flue probe but 2 weeks ago, we inspected the pipe and vacuumed the cat from the front (I didn’t realize it was 4” deep so it might have more in it). After vacuuming it burned much hotter and better for a week or so. Here are a couple of pictures. The stove pipe and the strange “oxygen” pattern when the door is closed vs open. When closed with the damper fully open and the cat either bypassed or open, the back doesn’t seem to burn but the front does. Open the door with the cat bypassed and the entire coalbed lights up with happiness.

 

[Phalynx]

You need to run the stove warmer too. The stove isn’t putting out enough btus at 450 to heat the place at those temps. Try it at 650.

Rake the coals forward when you reload. The air hitting them (bright red) will burn them down so they don’t fill up the stove.

If you have a ceiling fan, turn it on to circulate the air.

I can’t get it to burn any hotter. That’s the main issue. I have raked the coals forward and loaded wood to the back, That wood just chars and doesn’t really burn unless it comes forward. Ceiling fan is on full. We have a temp sensor at the top of the loft an down stairs so we know how much heat it up there.

 

[stoveliker]

The fact that after vacuuming it burned hotter is consistent with having too much draft.
Clean the passages,.and you get good burns. Then soon you end up with anemic performance again.

19 ft straight up is not much but with -20s F outside I think you have too much draft, quickly clogging up the cat, leading to the cat stalling, ending up with coals.
And when you open the door it is with the bypass open,.so no smoke rolling out because the draft immediately picks up as you bypass the clogged cat.

That's my $0.02

 

[Phalynx]

So I need a stove pipe draft control?

 

[stoveliker]

That would be my suggestion indeed.
Your draft will vary hugely anyway between 32 F and -20 F, and a key damper in the pipe will help you dial it down to similar values.

 

[Quirke]

While sounds like your draft is likely too strong, one more piece of information that might be useful in diagnosing your situation is your burn time on a full load.

Is the stove eating wood and sending the heat up the flue? Or is the thermostat throttling down the burn rate, requiring the factory fan kit to help extract heat from the stove and allow it to provide more air/oxygen to the fuel?

You could try using a box or pedestal fan directed at the stove to help transfer heat from the stove to the room and see if that has a noticeable effect.

 

[Phalynx]

Burn time is not very long at all. A full load will burn maybe 4-6 hours. I did try a fan in the back but it didn’t seem to help. I am going to try a fan again to see though.

 

[stoveliker]

But that's with coals (and thus burn time) left

While a key damper is cheap, you may benefit from a manometer to measure the draft (and so you can dial in your key damper based onto the draft you have).

 

[Highbeam]

The fuel will always burn front to back. That’s because all combustion air comes from the air wash in the front glass. When properly loaded, full, you can’t see the back until the front burns away.

You can shove your cell phone up in front of the catalyst and take a picture looking into the cells to verify whether it’s clogged. Sure sounds like it. If so, you can sometimes blow it out or vacuum it out in place. Don’t remove the cat without a new gasket.

You can only check moisture content on room temperature wood. Cold wood reads falsely dry.

Do you have a bird screen on the cap? Those things clog up fast and ruin your burn.

 

[Highbeam]

Burn time is not very long at all. A full load will burn maybe 4-6 hours. I did try a fan in the back but it didn’t seem to help. I am going to try a fan again to see though.

Don’t worry about the fans. Sure they help but are not terribly important. You’ve got something else going on.

 

[Todd]

What does your cat probe read? Is it glowing red? If so that means it should be over 1000 degrees and working as should.

 

[moresnow]

I did try a fan in the back but it didn’t seem to help.

Placing a fan behind the stove is likely to give you unfavorable results. The stove takes its combustion air in from the rear. The fan behind the stove seems to reduce burn time from my experience. Placing a small desktop fan in a cold room gently blowing cool floor air towards the stove seems to help spread the heat nicely. Worth a try.

No BK should be sold without the factory fan kit IMO. It truly makes a very significant difference in heat dispersion. Critical in colder parts of the world. Alaska qualifies as being cold