Smoky smell from creosote residue

[bocotim]

Hi Folks,

I am getting a strong smoky smell in the house when I use my new wood burning insert.

We just replaced an old fireplace insert that vented directly into the chimney/flue and had no connection to the chimney cap. I had that chimney cleaned, but there were years of creosote build up in the flue and some residue left over.

The new insert has a vent kit and stainless steel flex tubing connecting the insert directly to the chimney cap. The installer sealed the cap and the connections to the tubing so that we are pretty confident the smoky smell is not coming directly from burning wood, and down drafts do not seem to be a problem.

We suspect the smell is coming from the creosote residue that is left on the walls of the flue and it is gassing out as it heats up. Since the cap is now sealed, the smoky smell has no place to go except back into the home where it is creating quite a stink.

Several questions:

Does this theory sound plausible or is the smell likely caused by something else?
Will the problem get better over time as the residue eventually gasses off? How long?
Is there a way to fix it? How?
Should I try to seal the area between the insert surround and the uneven moss rock face of the fireplace? Seems like the gas has got to go somewhere though, so I am not sure sealing around the surround would help much, or would it?
Would it help to unseal the chimney cap so that gasses could escape out the chimney?

Thanks. Your suggestions/advice are greatly appreciated.

Tim

 

[Sprinter]

Welcome to the forum, Tim.

Most likely the smell is the insert's paint curing. It needs a few burns at around 550 or 600F or so to cure. Meantime, it will give off unpleasant fumes. The fumes apparently are not toxic, but keep some windows open and maybe a fan until the fumes stop. Sometimes it will even set off a smoke alarm.

How many burns have you had so far and how hot is the insert getting?

 

[bocotim]

Welcome to the forum, Tim.

Most likely the smell is the insert's paint curing. It needs a few burns at around 550 or 600F or so to cure. Meantime, it will give off unpleasant fumes. The fumes apparently are not toxic, but keep some windows open and maybe a fan until the fumes stop. Sometimes it will even set off a smoke alarm.

How many burns have you had so far and how hot is the insert getting?

Thanks Sprinter. We just got the new insert installed last week, so we have only had a couple long burns. We definitely smelled the paint curing at first, but that seems to have subsided quickly, and now we are just getting the strong wood burning, smoky smell. Not sure how hot the insert is getting, but we have had the windows open in below freezing temps and fans pulling in fresh air, and the house still stays warm.

Hoping the wood smell subsides soon.

Tim

 

[danimal1968]

Thanks Sprinter. We just got the new insert installed last week, so we have only had a couple long burns. We definitely smelled the paint curing at first, but that seems to have subsided quickly, and now we are just getting the strong wood burning, smoky smell. Not sure how hot the insert is getting, but we have had the windows open in below freezing temps and fans pulling in fresh air, and the house still stays warm.

Hoping the wood smell subsides soon.

Tim

If you read through this old thread from some years back, it suggests that a wood smoke smell is not likely to be from creosote.

https://www.hearth.com/talk/threads/novice-concerned-with-creosote.10294/

 

[Sprinter]

Just shooting from the hip here. I don't think you would mistake the smell of creosote for wood smoke, but it's hard to tell without being there.

If you are opening the door to reload or something, it's likely that some smoke will spill out and that can linger for a long time.

Describe your wood supply. That is, species and how dry it is. Have you checked the wood with a moisture meter to be sure it's really as dry as it needs to be (20-25% moisture content)? Insufficiently cured firewood can cause all kinds of problems.

Don't know if it's relevant, but is there a block off plate installed?

Also, what model insert do you have?

 

[bocotim]

Just shooting from the hip here. I don't think you would mistake the smell of creosote for wood smoke, but it's hard to tell without being there.

If you are opening the door to reload or something, it's likely that some smoke will spill out and that can linger for a long time.

Describe your wood supply. That is, species and how dry it is. Have you checked the wood with a moisture meter to be sure it's really as dry as it needs to be (20-25% moisture content)? Insufficiently cured firewood can cause all kinds of problems.

Don't know if it's relevant, but is there a block off plate installed?

Thanks for the feedback.

The smell we are getting is very smoky - like sitting around a campfire. It is coming from the gaps between the insert surround and the uneven surface of the moss rock fireplace. Some smoke spills into the room when I reload firewood of course, but I don't believe this is the source of the problem. We leave the windows open and fans going, and the smell doesn't seem to subside as long as wood is burning in the insert.

The wood supplier indicated that the wood he delivered is a mix of hardwood, mostly elm, with some russian olive and fruit woods mixed in. They said it was cut May of 2013. It seems very dry, and I don't have trouble burning it. I do not have a moisture meter to measure it.

Also, there is no block off plate installed.

 

[Sprinter]

Would your installer be willing to come out and help troubleshoot?

Also, regardless of whether your wood supply is relevant to this, it is recommended that you go ahead and get a moisture meter (around $20) and check the wood. Open up some splits and apply the meter to a fresh face. Without measuring it, you have no way to know for sure and it's so important. Anything above 25% needs to be dealt with and 20 is ideal.

 

[bocotim]

Would your installer be willing to come out and help troubleshoot?

Also, regardless of whether your wood supply is relevant to this, it is recommended that you go ahead and get a moisture meter (around $20) and check the wood. Open up some splits and apply the meter to a fresh face. Without measuring it, you have no way to know for sure and it's so important. Anything above 25% needs to be dealt with and 20 is ideal.

I have been in contact with the installer. He hasn't been back out, but he thinks it is just a matter of the insert completing the curing process. He suggests doing a few more burns first. If that doesn't take care of it, I will request a house call to troubleshoot.

I'll pick up a meter - thanks for the suggestion.