Odor from chimney/pipe

[MMH]

Hello all still newbie here need you’re help/advice. Got stove installed about a month ago (Bk ashford) currently in shoulder season so burning at night and in mornings mostly. Had inspection done which reports I need brackets/stabilizers for chimney exit, company that installed stove completed this. So that night (after bracket install) I load stove but had a difficult time starting my fire. During the start a few pieces of my wood smoked pretty heavily for probabaly a good 15-20 minutes. After this period fire finally got going and after getting established (another 10 minutes or so) I noticed there was an immediate odor. Smelt like hot metal/chemical like smell.

My pipe temperatures up to my ceiling were running anywhere from 600-900. I’m measuring with a IR/temp gun, so those temps are with the ~ + 50% (double walled pipe). My pipe never got red/glowing, I checked outside and nothing red/glowing, nothing coming out of chimney. Lots of noises coming from pipe, sounded like something dropping from pipe to bottom. This proceeded for about 15 minutes or so and then it stopped. No more noise, no more smell, temps right back to where I’m used to seeing them so far. Granted only been a month but never had anything like this. I have some theories.

Theory 1 is perhaps when brackets were installed some kind of adhesive was used or chemical which was volatile and sunk down pipe with the cold temps; however this doesn’t seem to fit much as I looked and the brackets are collared (not drilled into pipe etc) and a chemical burning off shouldn’t last that long, also if an adhesive it would have been strictly on the pipe section exiting from roof not entire length of pipe. So, I think that’s unlikely. Theory 2 is creosote. I’m thinking I’ve probably had some build up (albeit minimal) over the month. Then with this fire heavy smoking for that time frame probably led to build up that was in the liquid form and as soon as my fire actually got going and up to temp it was burning it off. However this seems a bit odd also because this didn’t smell like smoke or spot or tar it just smelt like hot metal/chemical like. I’m usually pretty snap as I’m still new about using moisture meter and the feel and checking my wood, but this fire had a few pieces that I didn’t check that felt heavy (I just thought they were a bit dense). Needless to say it scared me a bit . So, those are my 2 theories, any advice would be much appreciated thanks.

 

[begreen]

My pipe temperatures up to my ceiling were running anywhere from 600-900. I’m measuring with a IR/temp gun, so those temps are with the ~ + 50% (double walled pipe).

Can you explain this a bit more? Was 600-900 the actual surface temp or did you double the actual reading? Was this with the bypass open?

 

[MMH]

Can you explain this a bit more? Was 600-900 the actual surface temp or did you double the actual reading? Was this with the bypass open?

I was advised that when using an IR/temp gun on double walled pipe to add approx 50% to the temp as the temp reading I see is outer wall and the inner wall is approx 50% higher; so, I was seeing outer wall/surface temps of 400-600.

 

[MMH]

I was advised that when using an IR/temp gun on double walled pipe to add approx 50% to the temp as the temp reading I see is outer wall and the inner wall is approx 50% higher; so, I was seeing outer wall/surface temps of 400-600.

Yes air controls fully open

 

[MMH]

I was advised that when using an IR/temp gun on double walled pipe to add approx 50% to the temp as the temp reading I see is outer wall and the inner wall is approx 50% higher; so, I was seeing outer wall/surface temps of 400-600.

Air fully open

 

[begreen]

An IR surface reading on single-wall pipe of 500º equals a flue gas temp in the 900-1000º range. Double wall stove pipe adds an extra layer of insulation from the inner wall pipe. IR surface temperature reading on double wall stove pipe is not an accurate measure at all. If the surface temp on the double wall was in the 400-600º range there is a good likelihood the flue gases were much higher, like in the 1200º+ range. What you were smelling was very hot metal and paint baking.

You need a probe thermometer for the double-wall pipe for an accurate sense of the flue gas temps. Condar makes a decent one.

 

[MMH]

An IR surface reading on single-wall pipe of 500º equals a flue gas temp in the 900-1000º range. Double wall stove pipe adds an extra layer of insulation from the inner wall pipe. IR surface temperature reading on double wall stove pipe is not an accurate measure at all. If the surface temp on the double wall was in the 400-600º range there is a good likelihood the flue gases were much higher, like in the 1200º+ range. What you were smelling was very hot metal and paint baking.

You need a probe thermometer for the double-wall pipe for an accurate sense of the flue gas temps. Condar makes a decent one.

Thanks I’ll look into getting one; any ideas as to what caused this? Also at that temp shouldn’t I be seeing something from my chimney (from outside) whether it be red or glowing or something coming out (flames or something of that sort)?

 

[begreen]

My guess is that it was caused by running the stove with the bypass and air open too long, but that is just speculating. I wasn't there when it happened. It's possible that the inner pipe of the double-wall was glowing red, but it was shielded by the outer wall. You never want to see flames coming out of the stove pipe.

 

[MMH]

My guess is that it was caused by running the stove with the bypass and air open too long, but that is just speculating. I wasn't there when it happened. It's possible that the inner pipe of the double-wall was glowing red, but it was shielded by the outer wall. You never want to see flames coming out of the stove pipe.

Yeah that’s where I’m getting tripped up, I’ve ran this stove plenty of times now with my air wide open for the entire burn and never had anything remotely close to this happen. Nothing seems to make much sense even with creosote buildup I find it hard to buy I’ve built enough creosote in a month to cause the observations. When this occurred my cat wasn’t even in the active zone yet. Just trying to figure out what I did wrong so I can prevent this. Also once I get a probe what is a good temp for flue and what are temps to avoid? This is something I haven’t been able to find specifically regarding bk stoves?

 

[begreen]

Was there any noise associated with the high temp incident? It is possible that there was creosote buildup in the pipe that caught fire, especially if the wood is not fully seasoned. Inspect the interior of the stovepipe and chimney before cleaning. If there is a black, popcorn-like coating then it's possible there was a small chimney fire.

What is the flue setup? Does the stove pipe go up to a ceiling supported chimney or out the wall to a tee and exterior chimney?

The probe temp should be below 1000º and more typically in the 4-600º range.

 

[MMH]

Was there any noise associated with the high temp incident? It is possible that there was creosote buildup in the pipe that caught fire, especially if the wood is not fully seasoned. Inspect the interior of the stovepipe and chimney before cleaning. If there is a black, popcorn-like coating then it's possible there was a small chimney fire.

What is the flue setup? Does the stove pipe go up to a ceiling supported chimney or out the wall to a tee and exterior chimney?

The probe temp should be below 1000º and more typically in the 4-600º range.

Yes there was noise, sounded like numerous pieces falling down the pipe. With the noise and rapid high temps that then rapidly stopped I suspected a creosote fire, I just didn’t think I could have that much build up in the 1 month of use. I’m pretty anal about using a moisture meter on my wood so between that and the light feel of the pieces I believe they’re seasoned. However like I said I grabbed a few pieces that I didn’t check and felt heavy which smoked heavily for 20 mins before my fire got established during this incident. I also cut my air at night pretty low but my cat has always remained active throughout my night burns. Perhaps this in combination with the heavy smoking incident gave me enough to cause a small fire? My pipe set up is completly vertical, there is no angles bends or horizontals.

 

[peakbagger]

IMHO you had a small creosote burn. Even if you have cat it still doesn't completely prevent unburnt gases from poorly seasoned wood from getting past it.

Creosote is not a standardized deposit it can start out wet and sticky and then slowly bake into a harder deposit that take a higher temperature in the stack to ignite. it can slowly build up with no issues but if you have hot fire and conditions are right that hard deposit can rapidly volatilize and flake off into burning flakes. Thus the snap crackle pop. I have seen one or two chimney fires and it always amazed me how high these burning flakes will rise up[ out the stack.

Lot to be said for stopping by a stove shop and buying a chimfex chimney fire flare.

 

[MMH]

IMHO you had a small creosote burn. Even if you have cat it still doesn't completely prevent unburnt gases from poorly seasoned wood from getting past it.

Creosote is not a standardized deposit it can start out wet and sticky and then slowly bake into a harder deposit that take a higher temperature in the stack to ignite. it can slowly build up with no issues but if you have hot fire and conditions are right that hard deposit can rapidly volatilize and flake off into burning flakes. Thus the snap crackle pop. I have seen one or two chimney fires and it always amazed me how high these burning flakes will rise up[ out the stack.

Lot to be said for stopping by a stove shop and buying a chimfex chimney fire flare.

Yeah I think that’s likely what happened; do you guys think it was the couple wet pieces of wood I used in that fire? I could be very wrong here but the wood I have at the moment is seasoned wood so I’m just trying to figure out how I’ve managed to build enough creosote to light it off? I suppose it’s also possible I’m very wrong about the wood and it’s not seasoned but I’m running out of ideas. Do you guys think I need to have the pipe cleaned and inspected before further use? Thanks for all the help

 

[begreen]

More likely there was a build-up over the month. This could be because the flue gases were too cool. A probe thermometer will help you watch this. Creosote starts condensing on the pipe and chimney interior when the temp falls below around 250º. Therefore you want the flue gases to be above 250º all the way to the top of the chimney.

What is the flue setup? Does the stove pipe go up to a ceiling supported chimney or out the wall to a tee and exterior chimney?

 

[MMH]

More likely there was a build-up over the month. This could be because the flue gases were too cool. A probe thermometer will help you watch this. Creosote starts condensing on the pipe and chimney interior when the temp falls below around 250º. Therefore you want the flue gases to be above 250º all the way to the top of the chimney.

What is the flue setup? Does the stove pipe go up to a ceiling supported chimney or out the wall to a tee and exterior chimney?

Yeah I’ll be getting a probe for the pipe. My pipe is completely vertical; from stove top straight up through roof to exterior chimney.

 

[ValleyCottageSplitter]

Sounds like you may have high draft? Over 25ft chimney? My double wall gets to 350°F surface temps at the most.

Also, one of my Ashford problems was from a clogged cat. Have you checked in there? That caused a similar chemical smell in addition to my chronic creo smell. It might come out of the cat probe or elsewhere if it is getting choked at the cat.

Second I got a hot metal smell everytime I installed any new screws in the pipe, for example, filling in the hole from my draft gauge. Don't assume anything has changed inside? Possibly some metal shreds have dropped from the bracket install above?

How much wood have you burned through it? It took me about a month to get rid of all the paint and other curing during December until I ran about 5 full loads at wide open.

 

[MMH]

Sounds like you may have high draft? Over 25ft chimney? My double wall gets to 350°F surface temps at the most.

Also, one of my Ashford problems was from a clogged cat. Have you checked in there? That caused a similar chemical smell in addition to my chronic creo smell. It might come out of the cat probe or elsewhere if it is getting choked at the cat.

Second I got a hot metal smell everytime I installed any new screws in the pipe, for example, filling in the hole from my draft gauge. Don't assume anything has changed inside? Possibly some metal shreds have dropped from the bracket install above?

How much wood have you burned through it? It took me about a month to get rid of all the paint and other curing during December until I ran about 5 full loads at wide open.

I haven’t measured all my pipe but stove to cap I’d guess at 15-18 ft. I’m going to be installing a temp probe before this winter. I talked to some more guys and had the pipe inspected/cleaned by my stove company and there was nothing in it, were thinking that there may have just been some more curing going on and as you mentioned it I only had a couple hot fires before then these incidents were the next few hit fires I had after I thought about it. I’ve also discovered a small part of door that isn’t sealing (failed dollar bill test) so I’ll probably tighten the door just a bit and see if that works, maybe that could have contributed also

 

[begreen]

A tight door seal is important, especially on BK stoves. If the dollar bill pulled out with no tension at all, then fixing the problem should make a nice difference.

 

[MMH]

A tight door seal is important, especially on BK stoves. If the dollar bill pulled out with no tension at all, then fixing the problem should make a nice difference.

I’ve only had the stove for a few months, I plan on adjusting the tension do you think that will work? I’m assuming this stove is much to new to be replacing gaskets etc

 

[begreen]

New, fat gaskets can compress. Tighten up the door a little and test again.

 

[MMH]

New, fat gaskets can compress. Tighten up the door a little and test again.

Thanks