Modern whole house fans...my electric bill $35

[Fledermaus]

San Antonio, Texas

Happily, the previous owner installed double pane energy star windows with about six inches of insulation in the attic, and I have installed a modern whole house fan.


http://www.tamtech.com/wholehousefanhv1000.htm

With night time temperatures in the 60s, last months electric bill was $35…no AC
I shut the windows during the days and the house would be 80 by 6pm. At night, just open the windows and turn the fan on. The house would be in the 60s again by morning.

[Warpy]

1. That's all my folks used while I was growing up

even after they moved to NC, where it gets awfully hot and steamy in summer. They'd turn the fan on overnight, turn it off in the morning and close heavy drapes on the sunny side of the house. The house stayed cool all day.

Here in NM, most of us use evaporative coolers, something that works really well with the arid conditions. On very hot days, I'll leave it on fan at night to cool the house down. The cooling bill is about $15.00/month.

[Kadie]

2. How quiet is it?

We have one already, but it is about 10 years old. I don't use it very often because it is so noisy. I would be interested in replacing ours if we could find one quiet enough to run at night.

[Fledermaus]

9. The modern whole house fans are very quiet.

They are smaller than traditional whole house fans and move less air. The one I have uses 120 watts and moves 1000 cubic feet per minute. It is 16 by 24 inches and fits between the joists. It has insulated doors that automatically open and close and has an R value of 22.

I have a Tamarack but I have seen an other type at Home Depot. They are not cheep, but with the automatic insulated doors no heat gets in during the summer or out during the winter.

This is a good flash presentation from Tamarack
http://www.tamtech.com/whcflashdemo.htm

[XemaSab]

11. We've got one that sounds like the house is cleared for liftoff

We really only use it to air out the house when the smoke alarm goes off.

And that's because the fan in the kitchen... doesn't do the job. :P

[Wickerman]

3. When I was in San Antonio I looked into getting one of those

Had a hard time finding anyone who knew much about then (early 90's) and kinda let the idea die. Recently while visiting in Georgia I saw several homes with them and am considering getting one for the house in Minnesota. Thanks for the post as a reminder...

[MindPilot]

4. $35?! That's just for the fan right?

If you're trying to tell me your electic bill for a whole house for a month is 35 bucks, I ain't buying it. Unless you live someplace where power is like .002 per KWhr.

[Fledermaus]

7. Billing Period Apr 03, 2008 - May 05, 2008

Electric
Residential Electric
Service Availability Charge $4.25
Energy Charge 386 kWh x $0.06275 $24.22
Fuel Adjustment 386 kWh x $0.02152 $8.31
Regulatory Adj 386 kWh x $0.00213 $0.82
Total Electric Bill (Non-Taxable) $37.60

Current Electricity Charge $37.60
Current Natural Gas Charge $23.37
Total Current Energy Charge $60.97

City Services $17.99
State & Local Sales Taxes $1.45

Total $80.41

I have only started using my AC this week.

[Javaman]

17. The fan for a 1500 sq ft house is about $550. still not a bad deal in the long run. nt

[bananas]

5. Do you have an attic fan also?

[Fledermaus]

8. Yes, the previous owner installed a large attic fan.

I can easily get to the thermostat and adjust it. I kept the attic hot when the weather was cooler. Thermal gain is good in the winter.

I have set it to 85 now. I program my AC to 85 during the day when I'm not home.

[tinrobot]

10. Be careful with attic fans

If your house isn't sealed properly, the suction from the atti fan can actually pull air conditioned air out of the house and into the attic. Check the seals around ceiling vents and recessed lighting to make sure there are no air gaps. The power needed to run the fan can also add to your bill, the solar fans are the better in that regard.

I just researched attic fans and other methods of cooling my attic. All the experts seem to think passive cooling is the cheapest and most reliable, so I installed a ridge vent. I might also install a radiant barrier.

[Fledermaus]

15. Over venting your attic will cost you in the winter.

Hope you live in the south. Radiant barriers are good any season of the year.

[OKIsItJustMe]

6. I used to use a breeze-box in my folks' house

Put the breeze-box in an open, upstairs window, with the airflow set to exhaust. Open a screened cellar window. (The "breeze-box" is just encouraging the natural tendency of hot air to rise.)

Hot air is pumped out upstairs, outside air is drawn into the basement and cooled, then drawn through the house.

It worked great! (even during the day.)

[happyslug]

12. Reminds me of my old High School...

Now it is in Pittsburgh, and thus rarely gets 100 degree days, and the School year ended on June 15 of each year (The City of Pittsburgh Schools was the last school district to close each year in Western Pennsylvania, except for schools that had gone on Strike) but do to the massive fan in the basement, the blew a steady flow of air throughout the school from deep underground, the School was cool even on days when the temperature was over 90 (This was in June or September and then only for a dew days, the School was closed during the heat of Summer). All of this without ANY air conditioning. That is the advantage of a well design building, with good air movement designed into the building.

The key was air flow, a gentle overall movement of air from inside the building to the outside. It was rare to have air to come in from the outside, do to the air flow. Air was pumped from the basement to the rest of the building. This flow kept the hot outside aid out, in addition to having a steady flow of air. Pulling the air from the basement via ducts from the outside, kept the air cool, for the air was exposed to the cool area of the basement of the building. This cool air then was pumped to the rest of the building. Al this decades before the invention of Air Conditioning.

[4dsc]

13. Solar anyone??

http://www.solarroofvent.com/

A local radio station is advertising for solar attic fans.. Kind of pricey if you ask me..

[Fledermaus]

14. Yes, they work well. Best to have a thermal snap switch

They will vent in the winter, but a thermal snap switch will put an end to that. With a snap switch, the will only come on when the attic temperature is above 80F and the sun is shinning.

Optional Thermal Snap Switch is available to automatically turn off Solar Attic Fans during colder months.

If the previous owners had not installed an attic fan, I would have installed several solar attic vents with a thermostat. My utility gives rebates for solar attic vents. They sell them at Homedepot for under $300.

[kristopher]

16. Light colored metal roofing helps considerably and...

Don't forget to check the tax credits (both state and Federal) for anything to do with energy in your home before you make your final choices - even for things like roofing.