I can't use my fireplace until someone can help me solve this mystery!

[Mike1485]

Hello all my name is Mike and I am new to this forum and I am hoping someone can help me. I just purchased a new home last year and it has a zero clearance pre fab fire place in a great room above the garage. The room has a cathedral ceiling about 16 feet tall. I was so excited to make my first fire and once I got it going I kicked back on the couch I was so happy and relaxed with my new home. After about an hour or two I started to smell smoke but I couldn't see smoke coming in the room but the smell eventually got so bad my family had to leave.

My first reaction was the chimney must be dirty. So I called a chimney sweep and he cleaned the flue and said it was not that dirty and he is unsure why I am experiencing this as everything looks good to him. My next step was I bought a great wall of fire grate that is supposed to help heat the room and rid any back-drafts by keep the fire on rear wall. Once again I made a fire things were going great and once the ember bed started to develop and it was going for an hour or two the smoke smell began to start again. I have tried burning the fire with the outdoor air vent open and closed same result each time. After about a dozen fires with same result every time I call back my chimney sweep and told him again of my issue and he said maybe my outdoor air vent is clogged with spider webs or an old bees nest and to have that cleaned out which I plan on doing this week but I am not feeling optimistic that is the cause.

The house has a wind cap on it and my chimney sweep said the family who owned the house before me probably put that on thinking it would fix the issue which it has not. Anyways I am just very bummed out I have all this firewood stacked outside and beautiful fireplace that I can't enjoy. If anyone can give me some suggestions I would appreciate it. Thank you!

 

[ratsrepus]

Is like to see your chimney on the out side. There are certain dimensions and clearances that need to be maintained. Thinking maybe its to short. Also see if there is an internal damper that could be closed. I guess if you have had a sweep out there that part must be OK. So maybe post a photo of what I ask you to

 

[Mike1485]

Is like to see your chimney on the out side. There are certain dimensions and clearances that need to be maintained. Thinking maybe its to short. Also see if there is an internal damper that could be closed. I guess if you have had a sweep out there that part must be OK. So maybe post a photo of what I ask you to

Thank you outside picture posted, hope this helps.

 

[webby3650]

Maybe your forced air furnace is coming on in the middle of your burn and pulling smoke in somewhere remotely or even reversing the draft. Do you have a cold air return near the fireplace?

 

[bholler]

Thank you outside picture posted, hope this helps.

Did you try opening a window near the fireplace?

 

[ratsrepus]

Did you try opening a window near the fireplace?

thats a good idea, your chimney appears to be high enough and far enough away from roof lines

 

[webby3650]

thats a good idea, your chimney appears to be high enough and far enough away from roof lines

After an hour or two though? It’s defin worth a shot. Nothing like having the furnace on, a window open and a fire going!

My thinking is maybe after some time it’s cooled the house down so much that the furnace kicks on. Most modern HVAC systems will easily reverse the draft on a Fireplace.

 

[bholler]

After an hour or two though? It’s defin worth a shot. Nothing like having the furnace on, a window open and a fire going!

My thinking is maybe after some time it’s cooled the house down so much that the furnace kicks on. Most modern HVAC systems will easily reverse the draft on a Fireplace.

It is a test not a solution. If it fixes it clearly it is a problem with negative pressure. And it is not at all uncommon to only have spillage on the back end of a fire in a fireplace.

Or like you said it is an unbalance HVAC system

 

[webby3650]

It is a test not a solution. If it fixes it clearly it is a problem with negative pressure. And it is not at all uncommon to only have spillage on the back end of a fire in a fireplace.

Or like you said it is an unbalance HVAC system

He’s not seeing any smoke spilling, maybe it’s being pulled in somewhere else?

 

[bholler]

He’s not seeing any smoke spilling, maybe it’s being pulled in somewhere else?

Possible but I think it is more likely a small amount spilling that is unnoticed untill enough builds up in the house. But we are guessing at this point.

 

[yooper08]

Is the area above the fireplace dirty?

Are there other building envelope penetrations, whether it be on the roof, under the eaves, etc. for fresh air or for venting some sort of exhaust (bathroom, kitchen, etc.)?

Where is the smoke smell the worst and/or first noticed?

 

[kennyp2339]

Looking at your outside chimney check that little box vent and make sure it isn't plugged, looks like some type outside air connection.
Also not related to the smell of smoke but check your stove manual (if you don't have it look it up online) make sure you zero clearance unit is rated to burn for extended periods, some of these units are builders grade bare bones cheapo's, the manual will have a warning about burning for extended periods and the user must be mindful of that (think snowstorm no power type of situation)

 

[begreen]

Check the hvac imbalance by turning off the system. And try cracking open a nearby window or door to see if it helps. If not there is a chance of the smoke coming from an improper or sloppy installation. That would be bad because the problem is concealed. This could be due to ignoring clearance requirements, wrong chimney pipe, sloppy workmanship.

 

[webby3650]

This could be due to ignoring clearance requirements, wrong chimney pipe, sloppy workmanship.

Hopefully that vacu-stack cap is made for air cooled pipe and isn’t blocking the cooling wall of the pipe. I assume the sweep knew to check for this?

 

[begreen]

Hopefully that vacu-stack cap is made for air cooled pipe and isn’t blocking the cooling wall of the pipe. I assume the sweep knew to check for this?

Good question.

 

[bholler]

I am sure the vacu stack is not the proper cap.

 

[webby3650]

I am sure the vacu stack is not the proper cap.

They make one that’s designed for air cooled pipe as well as clay and insulated pipe.

 

[bholler]

They make one that’s designed for air cooled pipe as well as clay and insulated pipe.

Yes but they are not part of the listed system.

 

[webby3650]

Yes but they are not part of the listed system.

It doesn’t block any cooling capabilities, prevents down drafts, tested, listed, and approved for this use. But I know, it’s still not acceptable in your opinion. I personally wouldn’t use this cap because I don’t think they help in most situations, more often they cause draft problems I think. They sure clog up fast on a stove flue!

 

[bholler]

It doesn’t block any cooling capabilities, prevents down drafts, tested, listed, and approved for this use. But I know, it’s still not acceptable in your opinion. I personally wouldn’t use this cap because I don’t think they help in most situations, more often they cause draft problems I think. They sure clog up fast on a stove flue!

Again it isn't my opinion that matters it is the fireplace and chimney manufacturers instructions. Which all very clearly list caps that can be used.

 

[bholler]

And they are not listed as part of any air cooled chimney systems.

 

[webby3650]

Again it isn't my opinion that matters it is the fireplace and chimney manufacturers instructions. Which all very clearly list caps that can be used.

So, if the OP is experiencing down drafts that need addressed, your recommendation would be to remove the entire system and replace it with one that has an approved cap to help prevent downdrafts. So approximately a $10K investment when an $85 cap is available that might fix the problem.? I know your by the books no matter the situation.. I’ll just bow out, I don’t want this guys post to be deleted.

 

[Ludlow]

Your furnace wouldnt happen to be in the attic would it?

 

[Mike1485]

Thank you all for your feedback it is greatly appreciated. I have baseboard heat so I dont think the backdraft would be from the heating system unless its possible for the furnace which is in the basement to affect the air pressure upstairs. I did not try opening a window while fire was on because I dont want to make the house cold while trying to enjoy the fire and keep warm, but I guess to try it once for an experiment is a good idea. I am unsure about the cap being the right one but I assume it was installed to try and fix this issue with the previous home owner and it just didnt do the trick but they left it on there. I do see some soot on the front of fire place stone so smoke has been escaping over the years. I am going to get that outside air duct cleaned to see if maybe its clogged and causing the issue. The unit is a superior kr-43 unit not sure if it's a good unit or cheap junk. I am considering a chimney fan but I see they are pricey $900-1,500 bucks. Any other advice would be appreciated I hope I answered everyone's questions.

 

[webby3650]

If smoke is escaping, they make a piece called a smoke guard that can be added just inside the opening. It simply reduces the size of the opening a few inches. It’s often enough.
I assume you are burning with the doors open the whole time? Are there operational screens on it?