Forced Filtered Ventilation for House

[wooferhound]

 It's starting to get warm enough here in Alabama U.S.A. to open up the windows and blow some fresh cool air through the house. I've never been a big user of Air Conditioning because of the high electric bills. Don't care to keep the same air inside the house and recirculating it. Plus I really don't mind the heat, till it gets over 90 degrees or so. I've been in this house 8 months now and decided on a new project to help make the outside air better for cooling the place. The biggest problem with Blowing the Outside air into the house is the Bugs, Dust, Pollen and Rain. Of course a screen will take care of the bug problem but is no help on the other things.

 So I built this hood to go over the open window in the utility room. You can see a slot in the side where a filter will slide in. There are strips of wood mounted around the opening that the filter lays against, and another set of wood strips around the back of the filter to keep it in place real good. I was planing to put a little door hinged over the slot to keep the filter dry but, we had a heavy windy thunderstorm today and the filter stayed dry so, no door for now. I used the same filter Size as the one on my air conditioner unit, so I only need to remember one filter size. It looks like an airgap between the hood and the window frame but it's not. Everything sealed up nicely with a tight fit. I'll caulk it up later.

 Now I've got all the problems with the Bugs, Dust, Pollen and Rain. Inside the window I have a Box Fan, temporary for now but will be replaced with something a little stronger when it gets hotter. The fan is pluged into a box with a thermostat and a relay so I can control the temperature that the fan runs at. I can go to bed at night when it's hot, and the fan will turn off later that night when it gets cold, and of course it will turn on in the morning when it starts warming up.

I'm living 'Large' now !

Clean, almost free, fresh air, automatically controlled, flowing through the house . . .

  )}- W o o f -{(

[nanotech]

Very nice.

As I live on a dirt road that is frequented by farm trucks (read I have to change the dust filters on my computer quite often), this might be an idea I might try!!

[healerenergy]

I like your setup and I hope you don't mine me making a sugestion that will help your air flow. The thing with air is, it is basicly lazy so when your fan is running air comes from your room over the top of the fan. If you put a board or card board in the open space above your fan it should increase your air exchange effiency. I had to learn air flow dynamics in duct work and closed spaces when I was in the U.S. subnarine service.

[brians]

you can also put filter on box fan to

[wooferhound]

Tes ,  I have tried putting the filter straight onto the fan. One time I even made up a special cardboard box that had the fan on one side and the filter on the otherside. The problem comes from the vibration of the fan. It will shake the smaller stuff right through the filter. I would tape a 24x24 inch filter straight to the fan, but when I would untape it the extra motion and twisting of the filter would shake the dust off and into the house anyway. Plus it would not keep the rain out.

[wooferhound]

 I understand your suggestion, and you are so correct. The fan should be sealed to the hood just the same as the hood should be sealed to the house. All the air that the fan pulls should be coming through the filter. It's still to cold to worry about it much right now, but before the hot weather gets here, I'll have a much more powerful fan and a custom made shroud sealing it to the window opening.

[hiker]

if you have a crawl space under your house it should be a good source of cool air..

just extend your air intake down there..or rip a hole in your floor!!!! ouch.......

[wooferhound]

The Good news is: That's a GREAT Idea

The Bad news is: my setup is on the back of the house which

    is all slab. The front of the house has the crawl space

    Still, one day I'll probably utilize that coolness.

[healerenergy]

Another thing you could use is two DC fans from a car that would fill that space instead of one box fan. Then you could run it from a genny.

[electrondady1]

well, i just spent the last few days in the crawl space under one of my rentals and would not recomend the air under there to any one!  but i was thinking about heat excangers and a source of cooling air in summer.just wondering what kind of plastic pipe/ ducting would be healthy to breath through?

[brians]

i have used bread ties or zip ties  no answer about rain though

[wooferhound]

You're Right ,  I would never use the moist musty air from directly under the house. Maybe extending the intake for a 40 foot roundtrip under the house and then into the inlet of the air handling unit.

It seems that, after awhile you would just end up heating the crawl space to a point that you would no longer have the cooling effect ?

[wooferhound]

Another wonderful Idea.

 But I just have a 12 watt solar panal and a 200 watt wind genny. And the wind here in North Alabama isn't good enough to generate power but 1 of evey 10 days. Not to mention the single 30 amp hour battery to take the charge. Plus I won't even mention the fact that I don't have my wind genny in the air yet since the move.

I could run it for about 1 hour a day . . .

[pyrocasto]

Doubtfull actually, unless you are going for a big flow, with a good heat exchanger(lots of pipe under there).

[electrondady1]

yea, thats what i was thinking , alot of tubing underneath. i need to install bathroom and kitchen vents . i was thinkin,a continuous flow from those two areas down under the house through an exchanger to ether heat or cool incoming replacement air that could enter the house through a floor register. the place is sealed well .  but the system would not work when a door or window was open.

[Aelric]

just a thought, if you plan on using a pipe and forcing air thru it to cool the air down to prevent mold and other nasty things I read on one site for earthtubes (pvc or abs tubing that is ran underground to cool or heat air) that they just used an old towel soaked in bleach pulled thru the pipe.  It would be pretty easy to set up a pull rope and then just leave it in there till the next time you use it (one tip on the pull rope or pull string when you do use one be sure to tie a replacement one to it, makes jobs tons easier whether it be cabling or anything.)  Anyway just my 2 cents

[Kwazai]

maybe this will help with exhausting the hot air out-

http://chuck-wright.com/calculators/stack_effect.html

L8r

Mike

[wooferhound]

Thats pretty cool

My house is a 2 story house and I use the convective ventilation to my advantage. My filtered vent fan is on the bottom floor. and when I'm using it, Only the windows on the top floor will be open.

[HenryVG]

In my experience, putting your open windows on the ground floor to draw in air and putting a fan blowing OUT upstairs will give you a lot more flow. And then you can also choose an 'exhaust' window that's removed from sleeping areas to keep the sound away. Your 'intake' windows can be placed right next to your bed to let the cooler nighttime air be drawn over you. The only downside I've found is that about 3am, I'm freezing.