crazy question - attic fans (cost, electric, to work)

[Sea Ray Mark]

Originally Posted by Messing About

So would mine be working to enhance the proper air flow direction, since it brings outside air in from the bottom of the attic and forces it upward toward the ridge vents or should I not use this thing?

MA, the fan in your garage is probably there to exhaust hot air out of the garage to make it more comfortable and not necessarily for increased attic ventilation. Don't think it would have any negative effect on either area. You mentioned seeing some that go the other way which I don't understand why they would do that. Does seem backwards. Mark

[Sea Ray Mark]

Originally Posted by 03bluecoupe

My exhaust fan only kicks on when the temp is over xxx degrees in the attic. I forget what they set it at but wouldn't keeping the temperature down up there be a good thing? The exhaust is on a thermostat so it's not like it's constantly running.

Don't see how that could be a bad thing? I'm not being argumentative, it just seems to me that it'd make sense to keep the temp down.

I don't think you have anything to worry about. The main concern is that you have plenty of ventilation and having an attic fan the runs occassionally I don't think will harm anything but might be a matter of efficiency of running a fan versus natural convection even though the attic temps are being reduced somewhat. Personally if I have good insulation, good soffit ventilation, and good High mounted exhaust vents, I wouldn't run a fan. Mark (99RedVertM6)

[Old Gal]

I think you may have misunderstood what I mean. The type of attic fan, maybe it has a different name but that is how I have always heard them referred to, is designed to cool the entire house. The first house that I owned had one and it worked really well to cool the interior of the house until the outdoor temps reached about 90 degrees or so.

[03bluecoupe]

AH, so you're talking about one that actually goes into the ceiling of the house, typically in a hallway, and blows air from the living area into the attic?

[Old Gal]

Yes! My terminology was incorrect they are called whole house fans. I know the house I had one in was wonderful. We didn't have to turn on the A/C until the end of June. Would come home from work and flip it on, raise a few windows and within 5 minutes the house was very comfortable even in the Texas heat. With the cost of electricity I'm rather surprised that they are no longer used.

[wpc691]

These were really popular in New England back in the day - not sure if they still are. I'm thinking in SWF, the temp and humidity conditions are only right maybe 3 months out of the year. And then you've got another hole in the house for your insurance guy to wonder about. You'd probably save more by installing roll-down shutters on the West side of the house, and you get hurricane protection to boot.

[Messing About]

ahhhhh...the whole house fan. Yes, a completely different animal. When I was house hunting here, I saw one house with one. Seemed like a good idea but haven't thought twice about getting one since. Opening up all doors and windows, while running ceiling fans seems to serve the same purpose for me.

[Old Gal]

That's what I was thinking about the temperature and humidity whether it would really be that useful. Also if one would potentially create a mold problem from having the windows open and getting so much humidity into a house.

[03bluecoupe]

Yep, humidity is not your friend. I'd suspect most people have, or are about to fire up the A/C's and let 'em run until Winter for that reason alone. But I'm guessin'

[PCHI]

Not enough of both cool and low humidity days to be worth the time, in my opinion. More or less constant breeze also lets one just open a doors/windows for about the same effect. Once modern AC came available I suspect the whole house fan went the way of the buggy whip.