Possible Small Chimney Fire

[Locust99]

I have a blaze king princess pe32 that I purchased last year with about 8-9 feet of double wall pipe and 2 45s inside the house with 12 feet of class A pipe on the outside. I cleaned the chimney two weeks ago using my soot eater through the bypass. I got maybe a quart or so out of the chimney after burning 2-3 cords last year.

Anyways I was burning for only 2 weeks since I cleaned the chimney, with just a single fire at night. So the other day I went to start a fire and had the bypass open, I usually set a timer for the 10 or so minutes to check it while it reaches operating temp. My timer went off and as I was heading to the stove I noticed a hot smell and heard some popping in the pipe. I immediately closed the bypass, which the stove was up to temp and then turned the thermostat all the way down as I noticed something wasn’t right. My double wall pipe near the elbows was either burning off dust or paint as there was smoke coming off the pipe . The pipe was approx 450 degrees exterior from my IR thermometer. I got onto the roof and did not see any flames exiting the chimney.

What I am unsure about is how exactly my pipe could have gotten that bad in just two weeks. Unless my cat is somewhat plugged, I did not remove it. It routinely glows orange while in use, but I have seen some smoke outside when burning.

My wood is the same as I burned last year, not covered the best as wind had blown the tarp off, but typically low 20s for moisture content. Anybody have any ideas how that could happen so fast?

 

[Highbeam]

Maybe your sooteater cleaning wasn’t as good as you thought? Sure sounds like something was burning but maybe your technique just resulted in a ton of flames getting sucked up the flue.

I don’t recommend setting a timer, instead, sit there and close the bypass when flue temps exceed 500 internal or when the cat meter hits active. Whichever comes first. Hopefully your bypass gasket retainers are still good.

Have you calibrated your cat meter?

 

[Locust99]

It’s possible the soot eater wasn’t as good as I thought, but I did check it with a camera after and i didn’t see any buildup . I vacuumed out the bypass area as well, but didn’t pull the cat. After I get it looked at to make sure the pipes alright I will re clean it with a new soot eater head, mine was a 5 or so years old and I used it on a liner previously , so maybe it’s a little smaller.

Flames definitely must have went up the flue, I had the wood pretty close to the top of the firebox as well. I don’t have a flue thermometer yet but plan on getting one and drilling through the double wall pipe. I hope everything with the bypass is still good as well. It still makes a clicking noise.

I have not calibrated the cat thermometer, but after reading a post today I think mine was way off. The needle was at the bottom of the gauge 6 o clock, well below the first notch. I adjusted it today , but hopefully didn’t break it in the process. What do you do to calibrate it? Put it in the oven at 400 or something ?

 

[Highbeam]

It’s possible the soot eater wasn’t as good as I thought, but I did check it with a camera after and i didn’t see any buildup . I vacuumed out the bypass area as well, but didn’t pull the cat. After I get it looked at to make sure the pipes alright I will re clean it with a new soot eater head, mine was a 5 or so years old and I used it on a liner previously , so maybe it’s a little smaller.

Flames definitely must have went up the flue, I had the wood pretty close to the top of the firebox as well. I don’t have a flue thermometer yet but plan on getting one and drilling through the double wall pipe. I hope everything with the bypass is still good as well. It still makes a clicking noise.

I have not calibrated the cat thermometer, but after reading a post today I think mine was way off. The needle was at the bottom of the gauge 6 o clock, well below the first notch. I adjusted it today , but hopefully didn’t break it in the process. What do you do to calibrate it? Put it in the oven at 400 or something ?

Calibrate per the manual but to paraphrase, let the meter get totally cold, room temperature. Then adjust so the needle points to the tick mark at the bottom of the inactive range. There’s a confusing stack of nuts so the manual tells you where to hold and what to turn for adjustment. You’ve probably been waiting too long.

 

[Locust99]

I adjusted the thermometer, however I feel like my calibration is way off. At like 400 degrees in the oven my thermometer was at the 3/4 mark in the active range. I’m thinking I will have to order another .

 

[Todd]

How are your pipe joints? If it’s sucking a lot of air it can cool the flue gasses down and create creosote.

 

[Locust99]

Definitely have one loose pipe joint where it attaches to the stove. I have a separate post for that , the dealer is coming out Tuesday to fix it . Other joints I think are all solid

 

[Highbeam]

I adjusted the thermometer, however I feel like my calibration is way off. At like 400 degrees in the oven my thermometer was at the 3/4 mark in the active range. I’m thinking I will have to order another .

Don’t put it in the oven. That will tell you nothing. The cat meter is not an oven thermometer.

 

[Locust99]

Alright, I figured the cat had to be up to 500 degrees before using it which would mean the needle wouldn’t hit that range till around then. Hopefully it is still fine .

 

[Highbeam]

Alright, I figured the cat had to be up to 500 degrees before using it which would mean the needle wouldn’t hit that range till around then. Hopefully it is still fine .

In an oven the bimetallic coil is immersed in hot air and should overreact. When installed as designed, the bimetallic coil is far away from the heat source mostly being warmed by conduction through the long probe. There is no information that can be learned by testing a cat meter in the oven.

 

[Locust99]

That makes sense. Thanks for the detailed answer. I will cancel my replacement cat thermometer order for now in hope it’s still good!

 

[Highbeam]

That makes sense. Thanks for the detailed answer. I will cancel my replacement cat thermometer order for now in hope it’s still good!

If you ever do need a new one, condar makes a meter for the BK stoves that has actual numbers along with a better active range label. I consider it an upgrade.

 

[NHWS]

It's more expensive than the Condar, but Auber says that their AT100/AT200 work well as cat thermometers.

 

[Locust99]

Yeah, the probe I was going to order was the Condar 4”. Installers came out today and fixed the loose joint and screwed together another joint . They took apart the 45 degree elbows and all looked good and my chimney was clean. I re cleaned with a new soot eater head and it was clean. The large chunks in picture were from the cap.

Bad news though I tried starting a fire tonight it was low 50s out, not real windy but some 10 or so mph gusts and my stove had a draft reversal. Smoke was coming out of the cat probe hole and all around the stove. Maybe tightening it up reduced some of my draft? Never had that problem before . So I put it out with maybe a cup of water. So that was fun… I guess I’ll wait till it’s 40 or below again to try starting it up. I’m confused how I had a draft reversal.

 

[kborndale]

Did you warm the flue before attempting to light the fire?

 

[Locust99]

I didn’t other than I had the wood stove door open for 20 or so while I was cleaning the chimney out. I’ve never had an issue before in those conditions. The fire starter smoke was coming out the door so I closed it and then it came out of every hole in the stove. Hopefully it was a one off event.

 

[kborndale]

You should always warm the flue when cold starting. A piece or two of newspaper held near the flue, a blow torch or a blow dryer, even a candle. Gets the flue warm and draft going and you avoid smoke coming in.

 

[Locust99]

I will have to try that. I’ve never had a problem previously though, so this was a surprise. Must be tightening up the chimney impacted the draft.

 

[Highbeam]

I will have to try that. I’ve never had a problem previously though, so this was a surprise. Must be tightening up the chimney impacted the draft.

Closing leaks should only have strengthened the draft.

 

[Locust99]

Started a fire last night at about 50 degrees and I’ve had a fire going all day today. I have not any any issues with a reverse draft thankfully.
What I am noticing this year though is it seems like I will always have a little bit of smoke coming out of the chimney . My exhaust never is completely clean. It doesn’t look like steam as it can last 10-15 feet and still smells like smoke. Looking at the bypass when the stove is closed and cold it appears to be tight. Should you do the dollar bill test on the bypass and make sure nothing is leaking by that?

Also, I am planning on buying the auber thermocouple and install that into the double wall pipe so I can get an accurate flue temp.

 

[Highbeam]

Started a fire last night at about 50 degrees and I’ve had a fire going all day today. I have not any any issues with a reverse draft thankfully.
What I am noticing this year though is it seems like I will always have a little bit of smoke coming out of the chimney . My exhaust never is completely clean. It doesn’t look like steam as it can last 10-15 feet and still smells like smoke. Looking at the bypass when the stove is closed and cold it appears to be tight. Should you do the dollar bill test on the bypass and make sure nothing is leaking by that?

Also, I am planning on buying the auber thermocouple and install that into the double wall pipe so I can get an accurate flue temp.

These things aren't smoke free. Did your fuel have bark on it? A little wetter? Glass getting dirty? That seems to make it more smokey. A noncat is really easy to burn smoke free.

You can do the dollar bill test on the bypass door but I don't think that a perfect seal is all that important here.

 

[NHWS]

Mine smokes for a short while (as expected) after a cold or hot load. It smokes for an hour or so if the air is turned to very low (3:00) after a (re)load. After that, or it the air is turned up a bit (to 3:30), it cleans up to just heat distortion. 18' total stack.

 

[Locust99]

My wood for the most part has bark on it. The glass has never gotten too dirty aside from the edges. I tend to never burn it super low, maybe low 300s stove top temp. My old non cat in my previous home would be smoke free after it’s going for a while. I was just wondering if it was typical, as I’ve read most people say their stack is burning clean. Like I said mine usually always has a small bit of smoke coming out . With it being the heaviest of course after a reload or cold start with the cat just being activated .

My cat probe seems to be working after I adjusted it , because as soon as I closed the bypass the cat started glowing. So previously I was waiting too long.

Tested the bypass door with a dollar bill. It was tight all around so that’s good.

 

[moresnow]

My wood for the most part has bark on it. The glass has never gotten too dirty aside from the edges. I tend to never burn it super low, maybe low 300s stove top temp. My old non cat in my previous home would be smoke free after it’s going for a while. I was just wondering if it was typical, as I’ve read most people say their stack is burning clean. Like I said mine usually always has a small bit of smoke coming out . With it being the heaviest of course after a reload or cold start with the cat just being activated .

My cat probe seems to be working after I adjusted it , because as soon as I closed the bypass the cat started glowing. So previously I was waiting too long.

Tested the bypass door with a dollar bill. It was tight all around so that’s good.

With a good cat, glowing certainly indicates active (normally early in a burn cycle). However, a cat will be active for many hrs without showing a glow (or very little glow).
Something to consider. Watch your gauge. Cat color means little.

 

[Tron]

I’ve never had an issue before in those conditions. The fire starter smoke was coming out the door so I closed it and then it came out of every hole in the stove. Hopefully it was a one off event.

I've had a backwards draft and your symptoms occasionally. Mostly because someone was running ventilation in the house, like a bathroom fan venting to the outside, which may have created a slightly lower pressure inside. I don't have an outside air intake.

But opening a window near the stove quickly resolved that.