Disable attic fan or leave alone?
I recently bought a house that has an attic fan on a thermostat that seems to run whenever the outside temperature gets above about 70. The house was constructed in 1958, and is 2×6 wood frame on 16″ centers. The attic has about 2-3″ of blown-in cellulose, is pitched (I don’t know the pitch but it’s about average for a typical suburban house), and has a gable vent on each end (L-shaped house), soffit vents, and ridge vents.
This is in Albuquerque, NM, where it’s very dry and very hot in summer (90-110 degrees is a normal high from May – September).
I’ve tried to research attic fans, but the information is conflicting. As in, apparently they’re either good or terrible? On the one hand, I’m thinking the previous owner had a reason for installing it (it definitely was not a feature of the original home, nor probably was the ridge vent). On the other hand, I don’t want to waste electricity running it if it makes little or no difference. In the summer it runs from about 8am to 10pm so I’m sure it adds up. Cooling is one roof-mounted evaporative unit, with the ducts in the attic. Conditioned space is about 1450 square feet.
If it was easy to disable, I would try with and without, but it’s a long, long crawl and I’d really like to only unplug it once, ideally when I’m up there adding more cellulose (but I don’t have the time or money for that project right now).
Does anyone have any advice about what I should do here? Thanks!
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