Fireplace smells when not in use

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Melisandescott

New Member
Jan 25, 2020
1
CT
We just bought a house and have been dealing with some persistent fireplace smells.

we have a two story house with a finished basement. Mechanical room is partitioned off. 9 yr old furnace is vented to outside and has baseboard heating. We also installed a radon system when we moved in. Only fireplace is on main floor with ash dump in basement. We also installed a new dryer vent in the kitchen (the room next to the fireplace).

After our first couple fires, we noticed that the basement smelled like smoke, so we called a local chimney company out. They sealed the old furnace outlet and capped off the flue that had been used by the old furnace. They also warned that we may need a new liner.

The next fire also smelled in the basement. But we also started getting a lingering smell of “fireplace” in the living room where the fireplace is located. Chimney company came out again and did a cleaning as well as sealed the ash dump in the fireplace. He sealed the ash dump door in the basement with duct tape. He thought maybe when the furnace was pulling air in, it was causing air to come down through the ash dump.

this was just over two weeks ago and we hadn’t smelled anything in the living room. We did try one more fire the day after they came, but smelled smoke in the basement so put it out and haven’t had one since. Today, though, the living room smelled very strongly, and I could feel a draft coming in from the fireplace vents.

I guess our next step is to replace the liner, but I really think we may have a pressure issue in the house, but I don’t know even what to search for to figure out who can help with that. All I know is I don’t want to smell fireplace all the time!
 
Sounds like a reverse draft, BHoller can help you with that but hes probably in bed right now.
 
You are experiencing the effects of negative pressure. The house is losing air and the chimney is the allowing in the "missing" air. Sounds like you have a couple factors that are conspiring to cause the issue.

One passive problem is called the stack effect. which becomes more and more of a problem as you add multi levels. This happens when warm air rises through the building and exits, often through the attic. That air then needs to be replaced and the chimney becomes the path. Many times made worse because cold air in an exterior chimney wants to fall as well.

You can also have mechanical systems cause the same problem. Your radon system, furnaces, bath/kitchens fabs, dryers etc all are removing air from the envelope that needs to be replaced.

First thing I would do is to turn off the radon system when you feel the cold air coming in and see if it stops or slows. You should also check and seal any openings in the attic like poorly sealed attic stairs and see if that helps.
 
You could also put a damper on the top of your chimney that you can close when the fireplace is not in use.
 
We just bought a house and have been dealing with some persistent fireplace smells.

we have a two story house with a finished basement. Mechanical room is partitioned off. 9 yr old furnace is vented to outside and has baseboard heating. We also installed a radon system when we moved in. Only fireplace is on main floor with ash dump in basement. We also installed a new dryer vent in the kitchen (the room next to the fireplace).

After our first couple fires, we noticed that the basement smelled like smoke, so we called a local chimney company out. They sealed the old furnace outlet and capped off the flue that had been used by the old furnace. They also warned that we may need a new liner.

The next fire also smelled in the basement. But we also started getting a lingering smell of “fireplace” in the living room where the fireplace is located. Chimney company came out again and did a cleaning as well as sealed the ash dump in the fireplace. He sealed the ash dump door in the basement with duct tape. He thought maybe when the furnace was pulling air in, it was causing air to come down through the ash dump.

this was just over two weeks ago and we hadn’t smelled anything in the living room. We did try one more fire the day after they came, but smelled smoke in the basement so put it out and haven’t had one since. Today, though, the living room smelled very strongly, and I could feel a draft coming in from the fireplace vents.

I guess our next step is to replace the liner, but I really think we may have a pressure issue in the house, but I don’t know even what to search for to figure out who can help with that. All I know is I don’t want to smell fireplace all the time!
Don't replace the liner to fix this issue. I seriously doubt it will change a thing. It really sounds like pressure issues
 
Start with the 2nd floor. Are there any leaky windows, attic doors or attic vents in the ceiling?
Does the smell get worse after the dryer has been running? Is there a large kitchen hood and fan?
 
+1 to all of the above.

Some folks turn off their radon systems in the winter to minimize the negative pressure draw. Leaving it off for 4 months will not create a hazardous condition unless you have someone living full time in the basement. You could even hook up a timer on the fan part of the radon removal to run it overnight when you are sleeping, any reduction in its use during the winter is likely to help reduce the smoke smell a bit.

In my case I had an inelegant fix by covering the glass fireplace doors (when cold obviously) with a fleece blanket having the logo of my favorite sports team. That stopped the smell and negative pressure issues temporarily. Removed blanket when using fireplace, when guests were over, or for the summer months. Easy fix for me.
 
You could fix it right with a HRV/ERV. Anything you do with the fireplace won't address the fact that the radon system and dryer are pulling out more air than the house can supply.

You can address the stinky fireplace with a properly installed insert with a blockoff plate. As a bonus, now you have a heat source instead of a big hole in the roof.

If you just do the insert without fixing the airflow, the insert will have serious draft problems.
 
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