My heating contractor said it was ok to vent a 90% furnace throug the existing chiminey i do not think he is correct any feedback
Why wont they put a flashing on the roof and vent it with a nice one piece concentric vent kit?
Yes you may vent "through" an exsisting chimney.
The chimney must not be used for any other appliance and the pvc must extend all the way to the top of the chimney.
Karst means cave. So, I search for caves.
I've done it,
Just the way Karsthuntr said, works fine and looks good.
You should also put a cap on the top of the chimney.
Have the pvc go through that.
If you try to fail, and succeed.
Which have you done ?
victoff75: just curious, why did you not believe it correct when your heating contractor told you this?
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