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Heating & Air Conditioning Fireplaces

Two chimney flues

4 years ago

Our house has two flues - one for the fireplace; the other appears to terminate in a DuraVent duct exposed in the basement ceiling. It doesn't connect to anything. What could be its purpose? This didn't get mentioned during the inspection and we're not in touch with the former owners.

It's not bothering me, but I'm wondering if it should be sealed off in some way. Our fireplace is so drafty we can't use it, I have it blocked to the hilt with insulation. I'm wondering if this second flue is in any way responsible.

Thanks.

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Comments (5)

Aglitter
4 years ago
last modified: 4 years ago
I sure hope that's not dangerous. This might be a time to call in the pros. Blocking the vent could cause some serious trouble, as could leaving it open if it is allowing dangerous gasses into the basement area.
mtvhike
4 years ago
Is your house old? That second flue could be for a boiler or furnace which was removed.
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Seabornman
4 years ago
Could it have been for an older gas water heater or furnace?
Joe B
Original Author
4 years ago
House was built in '92. Must have been a furnace before they went with central air and heat. Cold air comes through into the basement, it should be capped on top.

We have a wood burning fireplace insert, with one flue going up from that. I've been wondering if that second flue somehow introduces cold air, but if it's going its separate way from the basement to the roof, probably not.

My problem might be cold hearth syndrome. I have no idea what's surrounding the flues, but if they're not within the home envelope, as they call it, I'm doomed. Cold air comes from everywhere, even through the bricks.

I just need to win some lotto money, then tear out that wall and make an addition.
mike_home
4 years ago
How is your house heated today and how do you produce hot water? The house may have been built with a gas 80% efficiency gas furnace which used the exhaust vent you are seeing in the basement. This could have also connected to a gas hot water heater. If the previous owner converted the heating and how water to electric, then this exhaust vent is no longer needed.

Does you fireplace have a chimney damper and do you keep it closed? Have you looked into installing a fireplace door?

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