Whole House Fan

[Czech]

I know this has been mentioned a few times, just curious if any of you that have installed these have any updates. I have a split level home, tuck under garage, attic access in the main hall upstairs where I would probably mount a fan. Questions for you:

1) Which make and model is best and why?
2) Is the big difference in price mostly quiet related?
3) My one kid has hay fever pretty bad, although we do open up when we can. Wonder if a fan would make things worse?

Thanks gang.

 

[Georgiadave]

Consider that a whole house fan leaks a great deal of heat in the winter. You probably should build an insulated box to fit over it in the fall.

 

[Czech]

Yep. My plan would be to have the opening be interchangable with the cover that is there now, fan for the summer, ceiling rock frame and weather strip and insul for the winter.

 

[maverick06]

My info can be found here: https://www.hearth.com/econtent/index.php/forums/viewthread/69820/

In summary,
1) I am pretty sure it is triangle engineering: http://www.trianglefans.com/ But, there are lots of good options. I didnt buy from them and am very happy. But triangle has a lot of good features, look at their site.

2) price difference = fan size and design (which can be related to how quiet it is), build quality, markup, ripoffs, sources, etc....

3) It will be like the outdoors, lots of outdoors brought inside. It will reduce inside allergens, but bring in those from outside. It will also bring in whatever moisture is outside. If being outside with the windows open is good, this will be too. If it makes the allergies worse, this will make it even more so.

As for insulating, you install the fan. That is a permanent installation. Then you build a foam box that goes overtop and seals the fan. This is easy and cheap to install. The install value is as good as the foam you install, easily better than the rest of the insulation.

Rick

 

[burnham]

Belt driven is quiter than direct drive. You need decent ridge vent or gable vents so the fan can work. We had one when I was a kid, I've installed ten or so.

 

[Dr.Faustus]

its a gamble with the allergies really. sometimes the fan helps me, sometimes i just gotta wall up and throw all the ac's on full blast. yes it runs up the electric bill but you cant put a price on breathing.

mostly for me anyway its worst when all the trees start dropping the pollen. the kind of days when you have to wipe the layer of pollen off your car.

times like that i'll wet up the area with the hose. helps keep it down. like spray the house, lawn driveway etc. cuts down inside dust too.

 

[Don2222]

Hello

Yes, I did this quite a while ago so I dug out the pics!

It works well, just open all the windows a crack.

However if you want to make the whole house 10 degrees cooler install rafter vents and Home Depot's Reflectix Foil like I did in the last pic

 

[SolarAndWood]

Do you guys do more than run it for 15 mins after the sun goes down to change the air in the house over? I never found the noise for that short a period to be that annoying.

 

[maverick06]

Mine isnt too near the living space, So it runs for hours on end. We bought a pretty nice fan and its not very lows. Actually its a better noise than the fireplace blower. The whole house fan is more of low rumble than the blower which is more high pitched.

Its the largest diameter, slowest spinning (at full speed), belt drive fan I could get. I elevated it up so it is above the louvers by a few inches. (helps reduce noise). I put foam between the fan and the box I built. I reinforced all the nearby rafters (to help spread out vibration forces). And before installation I tightened all the fasteners and I tack welded all the pieces with MIG. All that really quiets it down.

10 hours of runtime of the fan is equal to 1 hour of runtime of the AC. I also have it set to be run by my generator, which is spectacular in the summer!

 

[SolarAndWood]

10 hours of runtime of the fan is equal to 1 hour of runtime of the AC

Where do you have 10 hours of cool air stored or are you saying it uses 1/10 the power of AC for the same cooling effect?

 

[Czech]

Mav it sounds like you found a fan then did the surround and louvers? What I'm thinking so far, usually the final product is much different. I have power fairly close, plan to pull 110 from and existing wall plug in the hall up into the attic. I was considering trying to make an enclosure that sits in the existing access, then just replacing the insulated access cover with the fan during the summer months. The access is around 22"x33" or so, I need to get up there and measure good, this is just a guessimate from the bottom side. I guess what I'm thinking is it would be easier to use the access than cut ceiling and joists, the location is good in the hall between the three bedrooms. I've look at some of the smaller all included store bought ones, but I like to tinker (some call me cheap!) so was thinking I may have a DIY project too. Thanks all for the replies, lots to think about.

 

[woodgeek]

Czech,

Swapping in and out seems a pain. More importantly, you don't need to cut any joists--see the pics of Don's install. The air will go around. The big return plenum for my central/HP is set up the same way.

 

[Czech]

Czech,

Swapping in and out seems a pain. More importantly, you don't need to cut any joists--see the pics of Don's install. The air will go around. The big return plenum for my central/HP is set up the same way.

The more I think about it, the more you guys are probably right. That's the usual case! I need to get up there and look around and see the lay of the land (joists). Thanks to whoever supplied the link above to the maker, nice folks, waiting on some more info from them. Funny when you bring this subject up, many folks seem to say 'the house I grew up in had one'. This seems like a cost effective way to cool a house down most summer days here, I've been saying it for years looking at the temp gauge saying 85 inside and 70 outside. Wonder why you don't see more of these? Or have them as routine construction?

 

[woodgeek]

Wonder why you don't see more of these? Or have them as routine construction?

I personally think that there are two answers:

1--folks want a fully automatic set and forget system.
2--in many climates you still need an AC system, so this is an additional system that (in the minds of many) needs to justify its presence/cost
on the basis of energy savings. In a cheap energy era, folks are not going to be bothered to put them in or to use them if they are in.

The above pessimism aside, I think these work and I hope you enjoy yours.

 

[Czech]

Yep, makes sense wood. Kind of funny, during the day we're at work, by the time we're home the inside is ten degrees warming or more than the outside. Summer that is! Up north from here we saw -35 the last couple of nights! I looked around, bonus round was the adjacent fire detector, hardwired. Think I found my power source rather than pull form a wall socket below. Now to find a fan and louvers....

 

[maverick06]

I didnt want to cut the joists either. But the louver that I had needed it, so I needed to man up and chop through 2 joists. It wasnt too bad to do.

I had to box out the joists, put down foam strips and then the fan on top of that.

Here are pics of my install:

Since these pictures have been taken, I have built the insulation box for wintertime, and cleaned up the insulation and the wire (although you could argue thats the least of the concerns as the rest of the wiring in the house is the black stuff that predated romex.

Its not pretty, but it runs great and really helps cool the house. And sorry for the above confusion, it does use 1/10th the power. The fan is about 450 watts. The AC is (I forget exactly) about 4000 watts. It still makes for a great heat pump, but cooling is far cheaper with the fan. Of course this depends on what portion of the country you are in. In the north east, its good, although the humidity limits the functionality slightly.

Rick

 

[Czech]

OK you house fan gurus. So Czech has been shopping, for some reason money is a bigger issue of late (join the crowd, huh?). There's seems to be quite a gap between the direct and non-direct motors, around 2 bills or so, then the louver which seems to be included with the direct but extra for the other. So what is the main difference? Noise? What else? I'm not too concerned with the noise, the wife HAS to have a fan running at night to sleep anyways! Nice installs guys.

 

[maverick06]

i think the price is because:
1) noise
2) size of the fan, belt drives can run larger fans more efficiencly
3) CFM, believe belt usually can pull more air.

If you truely dont care about noise, just get a direct fan. just make sure you dont care.

 

[heat seeker]

You'll want to run it for more than a few minutes, probably. It will change the air in the house rather quickly, but the accumulated heat in the house itself, furnishings, etc., will heat it right back up. Besides, the moving air will make you feel cooler.
Make sure you have enough ventilation in the attic to allow the air volume to escape. The fan can't move air out of the house unless air leaves the attic. A belt driven fan is quieter than direct driven. I would go for a variable speed fan, since you can turn it down and still get a nice breeze in the house. Opening and closing selected windows will increase your comfort level, too.
You might consider a gable mounted fan. I had one in my last house, and really loved it! It was very quiet itself, and since it was at the end of the house opposite the bedrooms, it was silent. We had a louver setup in the hall ceiling for the air to leave the house, and the fan itself had its own louver setup to the outdoors. I've had several attic fan setups, and this was by far the best. It adds to the wiring, and you need two sets of louvers, but I think it's worth it.
Keeping the attic cooler will also benefit you by increasing your shingle life.
We have central air in this house, but still use the attic fan at times. This one is really noisy, so is getting replaced in the near future.

 

[Don2222]

I didnt want to cut the joists either. But the louver that I had needed it, so I needed to man up and chop through 2 joists. It wasnt too bad to do.

I had to box out the joists, put down foam strips and then the fan on top of that.

Here are pics of my install:

Since these pictures have been taken, I have built the insulation box for wintertime, and cleaned up the insulation and the wire (although you could argue thats the least of the concerns as the rest of the wiring in the house is the black stuff that predated romex.

Its not pretty, but it runs great and really helps cool the house. And sorry for the above confusion, it does use 1/10th the power. The fan is about 450 watts. The AC is (I forget exactly) about 4000 watts. It still makes for a great heat pump, but cooling is far cheaper with the fan. Of course this depends on what portion of the country you are in. In the north east, its good, although the humidity limits the functionality slightly.

Rick

Hi Rick
Very nice pics. Looks great. I have taken the blade off in the winter and put insulation on top to hold the heat.

What did you make your box out of for the winter? Do u have any pics of it?

Thanks

 

[Czech]

So I ended up going with a belt drive 30" fan, the price was right and I pick it up next week from Grainger. It will be a bit before I do the install, the upper hallway on our split level tuck under garage is a perfect location I believe (the joists even cooperated, need to relo a smoke detector and that's all). So once the snow melt in June or July, I'll post some install pictures here, I too will need to build a insulated box for the 10 months of off season. Thanks everyone for the input, it was great advice as usual! Pictures updated 3/16/11-