Whole house fan

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LLigetfa said:
To latch the door open, you need a door stop that holds in both directions like this.

baby-door-safety-door-stop-252x300.jpg

...or one of these.

180mm-Door-Holder-01.jpg

very nice door stops. where did you buy them?
 
BeGreen said:
Nice neat job down below, now get some staples in that romex and neaten it up in the attic. Seriously, those loose wires can be a hazard and are not to code.

HAHA I knew I would get called on that. I measures and left enough slack to properly attach the romex in place. I also have to straighten up the insulation. But it was about 11:30pm when I left the attic) The house was built in the early 50's (not knob and tube, not sure what the black stuff is called). so 90% of the wires are laying across the joists, under insulation, etc.... rewiring isnt an option, so it is what it is, but for the newly installed items I always do my best to insure they are done right.

I wasnt at all happy with the electrical aspect to the fan, the "junction box" that all the wires were to be fit into was about 2"x2"x2"It was too tight for easy work. But was able to get wire nuts on and electrical taped the nuts on and everything in place.

Thanks for calling me on that! Seriously, its important, but i have every intention of doing that tomorrow.

Thanks
Rick
 
black stuff is a early version of romex. back then ground wire was a option. some had it, some did not. next time your up there remove the tape. if you did the wirenuts right there is no need for tape. but the big reason for removing the tape is between the heat in the attic and the heat the motor makes the glue from the tape starts to liquify and gets into the splice and acts like a insulator. and soon enough the splice will fail. seen it happen alot in attics.
 
Congratulations on the new fan. We have one, and I like it a lot. There's some truth to the idea of summer A/C cost savings. Trouble is, this works best for me if I wait until around 3-4AM when it's hit the coolest overnight temperature, before turning it on, then run it several hours, then turn it back off as the sun resumes heating. During this short 3-5 hour window, you might see a significant drop in inside temperature from the heat rise from the previous day. We do. The strategy is to wait until its a few degrees colder outside than inside. This could be put on a timer, BTW, but I also play some games with opening strategic windows only for the cooling times, and otherwise keeping them all shut to avoid daytime heat gain through open windows. OK, so I'm a night owl and crazy enough to do this. Most folks who work day jobs will roll their eyes, but let me tell you, this actually works great!. Last summer I ran almost no A/C at all, the whole season- and didn't suffer. Houses have tremendous thermal equilibrium. It often takes a week or more for inside to begin to really catch up with high outside temperatures, using this strategy.

Run it during the day a lot and you are sucking in lots of warm, humid air. Yeah, you get the nice breeze effect, but you also get heat gain. Lots of it. Then turn off the fan and you feel hot- because you have heated your house with all that outside air. If you run a whole house fan constantly on High, you are probably pulling a similar amount of current compared to one or two window unit A/C, FWIW. (Remember- duty cycle on A/C) We used to run ours on High near continuously, sometimes for days or even weeks on end. You'd see that in your electric utility bill for sure. Now I run only a few hours a day and get much less temp rise in my house.

These things might not work the same for you. I'm on a wooded lot with lots of tall trees, many over 100ft. My house is in pretty much full shade in the summer. If you have full daytime sun exposure, all bets are off so far as my method. Experiment.

Something I doubt anyone else will think of- if you are a wood burner, remember that accidentally (or intentionally) turning on the fan while you have your wood stove going could lead to some smoke in the house. I had a little one time. I advocate a 'seasonal kill switch' in addition to any 'regular switch'. Or, in my case, I unplug the fan up in the attic and also reinstall some removable winterizing to eliminate the big winter heat leak the fan causes. I built a 5-sided attic-side cover box out of pink foam wallboard. I pile insulation on top of that.
 
I agree with Clutter that whole house fans are great. I also agree not to run it during the day - you can watch the thermostat increase. My fan is probably 20 to 25 years old and I tend to run it when it starts cooling down at night. I often wake up in the night and turn it off because I've gotten chilly! I will then turn it on and run it for a couple of hours in the morning, before it starts to heat back up. I live in an older house with no central air and I generally don't miss it. I live in the mountains and it usually cools down well at night. There might be about a week each summer that is really hot, but I can always cool down in the pool! I've never really lived in a house with AC and don't regret it. My fan is maintanence free, I've never done anything to it. I've pondered from time to time getting a newer and hopefully quiter fan, but it always comes down to if it ain't broke don't fix it!
 
What is the benefit to having a whole house fan? In what homes would it work best?
 
delaford321 said:
What is the benefit to having a whole house fan? In what homes would it work best?

Are you really here seeking to gain or share information, or are you here simply to spread your links around? Just askin' Rick
 
delaford321 said:
What is the benefit to having a whole house fan? In what homes would it work best?

you run the one fan instead of running 7 fans. run more than two 20 inch box fans and you are using more power than the whole house fan. and the whole house fan moves about the same amount of air as 4 to 5 twenty inch box fans. and it can be put on a timer or thermostat to shut it down in the middle of the night when it gets colder. 20 inch box fans run about 2 to 2.5 amps each. the whole house fan that the original poster install runs at 5. so if your running 5 box fans it takes the same amount of electricity as a 12000 btu window air conditioner running full out. so doing the math if your running a load of box fans why not run the air conditioner and take out the humidity at the same time. actually it would be cheaper to run the air conditioner because the compressor will cycle on and off as needed.
ok did i do a good job selling the whole house fan :cheese: now where is my commission
 
Growing up - we had a beach cottage down on the Northern Neck of VA. It had a whole house fan. You'd flip the switch and the curtains would draw in. We'd prop doors with old antique irons. If you didn't - the draft would pull the doors shut.

It was rare that we ever ran the window units. During the day - we were in the water and fishing. There was always a breeze coming off the water. At night - it would cool off quick.
 
Hello maverick06

I just did some testing on my whole house fan.

It is 88 degrees F outside in shade and 94 Degrees F in the Sun and the attic is 109.0 degrees F.

After running the Fan on High for approx 3 mins the temp in the attic went down to 93.2 Degrees F

It is 85 Degrees inside!

How is your fan working these days??
 

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Aren't the big ceiling fans just great? We love ours.

If you didn't get one of those self- adjusting louver covers with that fan, may I suggest that 1/2in grid wire cloth, spray painted white with Rustoleum, would make a very attractive ceiling fan cover without restricting the airflow much. You'd notice the fan a lot less, that way.
 
Cluttermagnet said:
Aren't the big ceiling fans just great? We love ours.

If you didn't get one of those self- adjusting louver covers with that fan, may I suggest that 1/2in grid wire cloth, spray painted white with Rustoleum, would make a very attractive ceiling fan cover without restricting the airflow much. You'd notice the fan a lot less, that way.

Thanks, that is a good suggestion Cluttermagnet

I do have the self adjusting louvres, just not in those pics. :)

They do move alot of air!

I also installed a radiant heat shield in the attic using proper vents and reflectix foil. That takes the whole house temp down over 10 degrees
See thread
https://www.hearth.com/econtent/index.php/forums/viewthread/71142/P15/

Do you have one?
 
If I understand your question right, all we have for ventilation in the attic is those traditional roof peak vents- the triangular, louvered, screened ones at each end of the house. The roof on our Rambler is pretty shallow pitched BTW, maybe 30 degrees or so. We have no ridge vents or other such things. It's worth mentioning that the builder did put in a pretty good ~2ft overhang, and it looks like they built in some small spaces (slots) to let it breathe, way down at the end of each rafter space where they join up with the fascia(?) boards- the ones you attach the gutters to.
 
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