So we moved the water heater and no longer need the vent that the one onse used that went through the brick to the house chimnney. Chimney is still being used by furnace, whats the best way to block it off? its I think a 4 inch duct. Thinking cover than using the chimmeny great stuff around it?
Mortar it shut where it goes through the brick.
do I have to replace with brick or can i just go over it like a patch?
I'd be inclined to just use mortar and patch it. The temps shouldn't be that high if it is just the exhaust off the furnace. If it was coming off the fire place, that would be another story.
yeah only thing using it is the furnace.. thanks!
They make galvanized, fluted sheet metal covers precisely for this purpose.
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