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akarusso

New Member
Oct 27, 2022
1
Long Island NY
Hi everyone, I’m new to this thread I have a chimney with two flues. The chimney was built in 1950 along with the house. I recently converted to a tankless navien boiler. the old furnace flue that had a liner in it is not being used any longer. The plumber put some sealant around the opening. The issue I’m having is I just had my first fire in the fireplace since doing this now I’m getting smoke in my boiler room behind the plywood that covers the hole with the flu is connected. The plywood has a little bit of a gap and I could smell the smoke coming behind. on the roof there are two flues. One for the boiler and one for the fireplace. is it possible that the smoke From the fireplace is entering the old flue that the boiler was connected to and being that they probably didn’t seal it good enough in the basement that it’s pulling the smoke into the basement?
 
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Yes.
Better sealing is one way, but the better way is to prevent it from getting in that flue in the first place. The way to do that is to ensure the fireplace flue terminated a foot or so higher than the unused.flue.
 
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Your fireplace is using combustion air from inside your home. In order to replace that air, it’s drawing air down the unused flue. That air contains smoke from the fireplace flue. You need to better seal the unused flue…
 
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Your fireplace is using combustion air from inside your home. In order to replace that air, it’s drawing air down the unused flue. That air contains smoke from the fireplace flue. You need to better seal the unused flue…
My new wood stove (main floor) is connected to a terracotta lined chimney which goes all the way to the basement, where an oil furnace (no longer functioning) is connected. to the same chimney. My chimney sweep put fiberglass in the chimney below the stove connection, and also where the stove flue enters the chimney. I worry about negative pressure from the basement but he tells me all is good.I had the ducts from the old furnace removed during a rehab of the basement. It's a 60+ year old house. I was thinking about covering the (now-useless) ducts, but I don't feel air moving when I have the stove running. Newbie also. Would appreciate your thoughts.
 
If you described it correctly, there are two big problems.
Two appliances on one flue is a big no-no.
Fiberglass is a big no-no.

I would suggest you get someone there with proper credentials. See https://www.csia.org/

The best way is to add a stainless (and insulated) liner into the terracotta connected to your stove. And to properly seal the basement flue connection.
 
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My new wood stove (main floor) is connected to a terracotta lined chimney which goes all the way to the basement, where an oil furnace (no longer functioning) is connected. to the same chimney. My chimney sweep put fiberglass in the chimney below the stove connection, and also where the stove flue enters the chimney. I worry about negative pressure from the basement but he tells me all is good.I had the ducts from the old furnace removed during a rehab of the basement. It's a 60+ year old house. I was thinking about covering the (now-useless) ducts, but I don't feel air moving when I have the stove running. Newbie also. Would appreciate your thoughts.
Well first thing you need to do is eliminate the fiberglass in both locations. Install a good well sealed cleanout door at the bottom and install the pipe properly into the upstairs crock
 
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If you described it correctly, there are two big problems.
Two appliances on one flue is a big no-no.
Fiberglass is a big no-no.

I would suggest you get someone there with proper credentials. See https://www.csia.org/

The best way is to add a stainless (and insulated) liner into the terracotta connected to your stove. And to properly seal the basement flue connection.
Yikes! The old oil furnace in the basement is out of commission, so no fumes from her. She is disconnected from the outside and tank is gone. Only fiberglass below the stove connection. Fiberglass is a big no-no? That's a concern. I am out in the middle of nowhere, this chimney guy is well-regarded, fluent in local, but his relaxation does concern me ( but I am a nervous nelly). Hard to find credentialed folks here. They don't want to do the 100+ mile drive. Pic is the flue from stove into the terracotta chimney. Problems with the stove already. Now I have to worry about the chimney?

20221116_151509_resized.jpg
 
Yikes! The old oil furnace in the basement is out of commission, so no fumes from her. She is disconnected from the outside and tank is gone. Only fiberglass below the stove connection. Fiberglass is a big no-no? That's a concern. I am out in the middle of nowhere, this chimney guy is well-regarded, fluent in local, but his relaxation does concern me ( but I am a nervous nelly). Hard to find credentialed folks here. They don't want to do the 100+ mile drive. Pic is the flue from stove into the terracotta chimney. Problems with the stove already. Now I have to worry about the chimney?

View attachment 302939
Fiberglass around the pipe is a problem as well and honestly pretty pointless it won't air seal well at all
 
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Yikes! The old oil furnace in the basement is out of commission, so no fumes from her. She is disconnected from the outside and tank is gone. Only fiberglass below the stove connection. Fiberglass is a big no-no? That's a concern. I am out in the middle of nowhere, this chimney guy is well-regarded, fluent in local, but his relaxation does concern me ( but I am a nervous nelly). Hard to find credentialed folks here. They don't want to do the 100+ mile drive. Pic is the flue from stove into the terracotta chimney. Problems with the stove already. Now I have to worry about the chimney?

View attachment 302939
Thanks for the link bholler. Certified comes up at the 75 mile range. Will follow up. Thank you, truly!