Whole House Fan

Second floor of my house gets considerably hotter than the first floor. I am considering installing whole house fan to mitigate this issue.
Does whole house fan realy help?
I was thinking about the fan that has insulation on top of it and which opens up when the fan starts. Until I read extermely bad reviews about this fan.
I really don't like to install regular whole house fan as an idea of huge uninsulated hole in my attic does not really click with me.
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My parents used a box fan, in upstairs window. Helped, a lot.
Does your house have full attic? Tell us a bit about insulation, and windows in your attic, or no windows?
Christopher A. Young Learn more about Jesus www.lds.org .
Second floor of my house gets considerably hotter than the first floor. I am considering installing whole house fan to mitigate this issue.
Does whole house fan realy help?
I was thinking about the fan that has insulation on top of it and which opens up when the fan starts. Until I read extermely bad reviews about this fan.
I really don't like to install regular whole house fan as an idea of huge uninsulated hole in my attic does not really click with me.
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one of the huge window fans, and a relative built a hinged frame for it so that I could swing it open to get to the window to close it in the rain.
Next two houses have had the hole-in-the-attic variety. I really liked the first of those, which I bought 20+ yr ago at Sears. It had a variable speed knob and the self-closing vents plus the company sold some sort of heat sensor that killed it in the event of a fire. Make sure you have good window screens - that fan worked so well that it sucked small bugs in.
Current house came with a small whole house fan. It has one speed - loud! So when I use it, it's usually just to start air circulating, and then I turn it off.
One problem with all of them is that(in addition to the bugs) they also suck in the humidity. As for the gaping hole in the winter, "they" used to sell plastic covers for the grates that attached with magnets. I've also taped plastic over the grates, and in the last house where I had really easy access to the attic, I used to throw an old quilt over it in the winter.
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Thanks. The others have given great ideas. My parents used to open the windows at night, and use a box fan blowing out, from one upstairs window.
Christopher A. Young Learn more about Jesus www.lds.org .
House is very well insulated and has R-49 attic insulation. The roof is gable and there is continous soffit vent and ridge vent. No other vents or windows.
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I got one. It's too fast and noisy. Panasonic has some smaller quiet fans. I have shutters, and I built a box above out of foam, with foam door. I sometime quick cool the house when it's cooler outside, but soon turn it off. I also sometimes clean the house with a blower !!! They used to sell a vertical belt driven model with less than 16 inch opening. Don't know if it's still around. A lot quieter. I still want to install another fan less than 500 cfm.
Greg
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We have one in central NJ. Yes, they really help.
We have a 4'x4' louvered grate that opens to the outside on a wall. The door that opens into the attic to let air flow is insulated.
--
Dan Espen

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consider one of these. Set it to blow out and open your BR windows. We had a large one like this but have switched to a smaller version that's quite efficient. I take it out and put it in a closet during cold weather. We use a timer that turns it on a couple hours before bed time and then shuts it off after several hours at night.
http://www.ventingdirect.com/air-king-9166-20-3560-cfm-3-speed-whole-house-window-fan/p441363?source=gba_441363
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wrote:

The fan can do wonders under the right conditions, but it is not an air conditioner. We use our in mild weather and it draws the cooler outside air into the house and flow is controlled by opening or closing windows as needed. It is also variable speed.
In the real heat though, I turn on the AC and the fan sits idle. Fans move air, but they do not remove humidity.
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Years ago (40) in another location I built one. 20 inch blade, belt drive.1/3 horsepower 3 speed motor. Bought a bladed set up that would open up by suction of fan. closed when fan turned off. Single story house. Installed in hallway. Would turn on and open windows on shaded side of house. This worked very well. At night time opened bedroom window and ran fan speed on low. No cool air problem in winter. blades sealed well WW
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The answer to that is sometimes, ie, when it's cooler outside and you don't have AC on. Then the fan can quickly draw cooler outside air into the house. Like if you've been away, come home and find it 80 inside and 70 outside. For it to work, you also need the outside air to not be too humid.
On the other hand, if the problem is that the upstairs is considerably hotter than downstairs with central air on, it's 85 outside, then the whole house fan isn't going to do you any good. I suppose you could turn it on to draw the cool air from downstairs up, but it's not going to be very efficient, because the air leaving from upstairs is going to need to be replaced by hot, humid outside air coming in downstairs. That will heat up the downstairs and place a huge load on the AC.
You also need sufficient attic venting so the air has a means of exist.

Having one that seals when off and is insulated is important. If the attic is accessible, some just manually cover it up with insulation in the fall.
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On Monday, July 9, 2012 2:04:37 AM UTC-4, snipped-for-privacy@optonline.net wrote:

I understand that I need to openwindows downstairs when operating whole house fan. I expec to use it when temperature outside is cool enough which does happen a lot of time ussually at nights.

Covering fan with insulation only at fall does not help much since the fan will represent a huge hole when not working during summer time in otherwise well insulated attic.
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On Sun, 8 Jul 2012 18:38:59 -0700 (PDT), ls02 wrote:

I had one of the fans with insulation on top and found that it didn't move enough air and was noisy.
I replaced it with one of these and have been very happy:
http://www.airscapefans.com/products/Shop/Natural-Cooling/Starter-Whole-House-Fans/Kohilo2
Also available in a larger size:
http://www.airscapefans.com/products/Shop/Natural-Cooling/Starter-Whole-House-Fans/Kohilo
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Interesting point. The problem of insulation vs airflow would seem to be an inherent part of any design where the insulation is part of the fan. For insulation to be effective, it has to be reasonably thick. And if it is, unless they have some fancy design that moves it completely out of the way, it's going to be in the way of the airflow.
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On 7/8/2012 8:38 PM, ls02 wrote:

that's the way whole house fans are. You just climb up there in the fall, take the belt off and cover it with the bat fiberglass insulation. in the spring, when it doesn't work (because the belt is off) you are reminded to go up and take the insulation off it and re-install the belt. For me, i just leave it uncovered. It's not that big a deal.
Having said all that about the fan, is your house air conditioned? You might try closing a couple or few vents in the down stairs and making sure all the vents are wide open upstairs. Opposite for heat.
--
Steve Barker
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How about a photo of the house, where you ae located, any trees, type of heating/cooling system, etc. Otherwise we are all just taking potshots at something we know very little about.
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wrote:

I just wanted to point out another option. We currently utilize an evaporation cooler here in Colorado. If you live in a area that has relatively low humidity, then this is a good option. It's similar to a house fan, but it sits on top of the roof. It contains a large rotating drum which pulls outside air through moistened pads and then feeds the cool wet air through the top floor of the house. You open a lower level windows to draw the cool air outside. This cools the entire house and provide fresh air. Unfortunately, it doesn't help much in high humidity as the air is already wet.
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If you are considering installing attic fan Consider shutters to be open electrically and with no dough in you mine have variable speed fan motor. If you can get shaded or polyphase fan motor similar to AC condenser motor you can variable speed control your self However if you are not electronic wiz get one all ready made for that purpose.

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Having electric shutters is a great idea for slow fan speeds. It would also open up ability to have thicker insulated shutters.
Greg
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