and yes, this is in very large part just an effort to not pay sdge fucking 85 cents per kwh during a heatwave to run a/c overnight. just rolling cool air through is way more effective than blasting a 6500 watt compressor/airhandler combo to actively cool.
and if you DO have a whole house fan, or are thinking about buying one, I wired mine (yes because im a lunatic) into home assistant by using a 'zooz multirelay' that talks zwave to HA. I even did a writeup here: https://community.home-assistant.io/t/how-to-quietcool-3-speed-whole-house-fan-using-zooz-zen16-multirelay-switch/494057
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