Quote:
Originally Posted by Xringer
Gary said,
There are a bunch of refs out there saying that AC powered attic vents don't payoff.
I think of my AC powered attic fan kinda like a very low cost heat pump.
It started up around noon today, but we never turned on the AC until about 3 PM.
By 6:30 PM it was cool enough to shut off the Sanyos again.
Without the attic fan, the house heats up earlier and stays hotter longer.
When we did turn the Sanyos on this afternoon, the house cooled down a couple of degrees, very quickly..
Right now, 7:45 PM, the ceilings are at 76.6F and the attic sensor is at 93.1F.
It's 76 indoors and 71.6 outdoors (and dropping fast).. 
In my case, I don't mind paying a few extra bucks for power,
when it allows us to enjoy more hours of mild summer weather.
Not really expecting the fan to pay for itself in 10 years..  |
Hi X,
Sounds like the way you manage the time that its on makes it work well for you.
I think there are a lot of variables -- how well the living space ceiling is sealed against airflow up into the attic, whether there is also a radiant barrier, how much power the fan uses, whether its a not so expensive DIY install or a more expensive install, ... I should not have made a blanket statement.
I got one of the solar powered attic vent fans when they were closing them out at Costco for $80. Its now installed near the outlet of my solar air heating collector in the shop to keep the hot air from stagnating up at the ceiling in the winter. It does a really nice job of keeping the air mixed up -- no controls needed it just runs automatically when its sunny
Gary