Basement 47 degrees in Winter
My unconditioned, unfinished basement gets pretty cold in the winter (as low as 47 degrees). It is connected to a 3 car garage that also gets cold in the winter (semi-conditioned at 40 degrees). We are in upstate NY.
I have sealed and insulated the rim joists so I can’t for the life of me figure out why the basement gets so cold. The only combustion appliance down there is a 76k btu power vented gas water heater.
Is it at all possible that the negative pressure caused between the combustion and power venting of the water heater is enough to draw in cold air which keeps the basement at these temperatures?
We have an excess of solar power so I wanted to replace the gas heater with a hybrid water heater (heat pump with resistance heat backup). However, in heat pump mode it’s the same as running a 4,200 btu air conditioner down there.
Do you guys think there’s any shot it would actually be warmer in the basement after getting rid of the gas water heater or should the infiltration caused by power venting and combustion be negligible?
Thanks for your time!
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