Should gas furnace registers be left open or closed when using a wood stove?
MKloman
| Posted in Energy Efficiency and Durability on
We have a gas furnace (fueled by propane), but because it’s too expensive to operate we purchased a wood stove insert. This is not only cheaper but does heat the entire 1900 square foot house.
My question is: Do we leave the gas vents (registers) open or closed when operating the wood stove (which is 95% of the time)?
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Replies
Mary,
It doesn't make any difference. In most cases, your furnace and your furnace's ductwork should be entirely inside your home's thermal envelope, so there is no need to close the registers.
If your home has ductwork in an unconditioned space (for example, an unconditioned attic), and if the duct seams are unsealed and leaky, sealing off the registers might make sense (to keep outdoor air out of your house, or to prevent indoor air from escaping). However, the dampers on forced-air registers aren't really airtight, so this measure wouldn't really prevent air leaks.