How To Use A Whole House Fan In A Two Story House

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Using a whole-house fan properly can lower heating and cooling costs, reduce indoor allergens, and freshen the temper of your home. Whole-house fans work past moving hot air out through gables or vents and drawing libation air in. Whole-house fans therefore don't piece of work very well when the outdoor temperature is much higher than the indoor temperature or when the outdoor humidity is high. New products have temperature and humidity sensors to add comfort.^[ane]

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one
Decide the size of the fan your home volition need. Calculate the foursquare footage of your home. Well-nigh whole-house fan manufacturers will list the capability of the fan to the square footage of your house. Some believe a complete change of the home's air should exist accomplished every 3 or 4 minutes.
- Many fans include a CFM (Cubic Anxiety per Minute) rating. The greater the CFM value, the more air it can move. But divide your dwelling house'due south cubic feet past the fan'southward CFM rating to upshot in the number of minutes to commutation the air. ^[2]
- Consider that larger value CFM fans oft take a larger physical size and/or higher rotational speed. Equally a result, they may exist more noisy than lower value CFM types. Noise levels might too dictate where in the abode the fan should exist installed. A 2000 square foot habitation with viii pes (2.4 m) high ceilings volition, in theory, have all the air in the house completely changed in 8 minutes with a 2000 CFM fan (and windows open in each room). Likewise, a 4000 CFM fan will do it in as footling equally 4 minutes!
- Here's how one arrives at those figures. A 2000 CFM fan moves 2000 cubic foot volume of air in a minute. A 2000 square foot house with an 8 foot (two.4 m) loftier ceilings has xvi,000 cubic feet of space (2,000 sq/ft area * 8 ft = sixteen,000 cubic feet). 16,000 cubic feet of infinite divided past the capacity of the fan, 2,000 cubic feet per minute, equals eight minutes (xvi,000 cu/ft volume of air divided by 2,000 cu/ft of air moved per infinitesimal = eight minutes to move that volume of air).
2
Ensure that the home has at least one. 5 times the area for discharge as the opening you cut into the ceiling for the fan. The air being drawn up by the whole-business firm fan needs to be discharged somewhere, and yous want that procedure to move smoothly.
- Example: a ii' 10 2' opening for a fan results in iv sq Ft. And so, this 4 sq Ft X 1.5 = 6 sq Ft. Look around your cranium. If you have two gable vents that are 1' x two' = two sq Ft each, equaling only 4 sq Ft total. You probably have screens over them, so knock off 20% to 30% from 4 sq ft and you're downwardly to around 3 feet (0.9 one thousand). If you do not accept acceptable exhaust vent area, add some.^[3]
- Ridge vent, soffit vents or enlarge the existing gable end vents are ways to obtain adequate exhaust ventilation area. Deduct for any and all blockages (screens, slats, lattice, etc). Mostly, 10 sq Ft of attic discharge surface area is more than sufficient per fan in residential applications.
- That said, only very largest of homes would crave multiple fans, and that is simply when many windows are open up and the resulting cakewalk is not satisfactory. Of class, closing windows increases the air flow (CFM) through those that are left open. More than on this beneath.
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3

Make up one's mind where the best intake locations are (windows or doors). These locations will have screens. Locations without screens are unsuitable. The fan should non be behind a door, but rather in a common hallway.
4

Close the damper on the fireplace. If the damper is left open, outside air volition exist drawn down the chimney, bringing in soot and odor.^[4]
5
Open but the windows that take screens in the room(southward) in which you are in. A 2000 CFM whole house fan will try to movement 2000 CFM of air. This fan is limited just past the fan's 2000 CFM rating and the amount of area to intake (windows) and discharge (gable & ridge vents, etc) air surface area. Pulling that 2000 CFM through ii or 3 windows instead of 10 windows results in a much stronger breeze.
- Let's do the math: 2000 CFM via x windows = 200 CFM per window. Now, shut all but the four windows of the rooms you're in. 2000 CFM via 4 windows = 500 CFM per window (If windows are large enough)! That'due south a big difference. Information technology's this breeze that creates the evaporative cooling of the skin.
- Moving air in an unoccupied room for hours doesn't arrive experience cooler than it would if yous had just entered information technology and and so opened its windows. You lot can plough this into cash in electric bill savings past running the fan at a lower speed with ii or 3 open up windows instead of high speed with x+ open windows.
- Don't run the fan when no i is domicile, every bit this just wastes electricity. The instant the fan is turned on, information technology creates a cakewalk that immediately cools y'all down. You can't become that kind of instant relief when y'all turn on an air conditioner.
- Maximize your savings: Windows that are open on the shaded side of a house will bring in much cooler air than those open in a higher place a sun drenched blacktop.
6
Consider adding boosted vents for the attic infinite. Allowing hot air trapped anywhere in the attic out prevents that oestrus from radiating downward through the ceiling into the living space, and reduces cooling load.
- Turbine ventilators work great, but strong winds can crusade a downdraft and create static pressure, which will destroy the fan'southward ability to frazzle the habitation'south air.
- Under eave vents are cheap to buy, cheap to mount, and provide a great mode to frazzle the air. If your house has eaves, mountain as many as possible under the eaves to let proper ventilation. This is the all-time way to exhaust, as the furnishings are twofold: The commencement is that hot stale cranium air is exhausted out, and second, with nether eave vents the air travels forth the roof line and down, which provides cross-ventilation for the attic itself. These are much easier to add than a ridge vent or powered attic ventilator.
7
Be rubber. Accept your work permitted and inspected. Most localities observe the National Electrical Lawmaking^[5] or some derivative of it. Follow your local lawmaking.
- If you insist on doing information technology yourself, make sure you install a service switch in the cranium if information technology is possible to work on the fan from the attic space. An outlet nearby would probably come in handy to plug in a drib light or power tool.

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Question

Can you run a whole house fan with the windows closed?

Walter Brant
Handyman

Walter Brant is a wikiHow community fellow member and correspondent who has been repairing and restoring houses with over 30 years of feel. He works with homeowners to make a broad diverseness of improvements to make their homes more comfortable and liveable.

Yous should open the windows in the rooms you're using to assistance absurd them down faster.
Question

Can I run a standing room fan along with the whole house fan?

If past "room fan" you mean ceiling or floor fan, then yes. However, it's not recommended to operate your HVAC organization fan at the same time time as the whole-business firm fan.
Question

Exercise I demand to exit the wooden door of the cranium open up while running an attic fan?

No, do not exit the wooden door or access hatch to the cranium open when running the whole-house fan. Remember, the fan works by pulling air through windows from outside and pushing information technology out of your attic vents. Leaving an attic door open would push that air back into the house and defeat the purpose of the system.
Question

How practice I use a house fan to keep the downstairs warm in winter?

At the warmest part of the day, open up a window or two and turn on the whole-house fan. Never operate the fan without opening windows, or if the air outside is colder or hotter than you want the within of your house to exist.
Question

I similar to open up a couple of doors to cool the firm off. Is this an efficient way to utilise the fan?

Aye, as long every bit you merely open the doors for the rooms in which you are in. Also, just open up 2-3 doors; if yous open up also many, the efficiency goes downwards.
Question

Will running an air conditioner downstairs cause the cool air to draw upstairs?

No. A whole-house fan pulls in air from outside, through a window, then pushes information technology out your attic vents. Never operate the fan without opening windows, or if the air exterior is colder or hotter than you desire the inside of your house to be.
Question

We merely bought a firm with a whole house fan, but I cant detect any controls for it. Where would they exist?

Dorsum trace the wires from the fan. No incertitude it will bear witness you a full general location where to offset looking for the control.
Question

Can I close my windows and leave the fan running?

You need to go out at to the lowest degree one window open fully or several windows open up a little. This volition help the fan circulate the air up and down through the house.
Question

How do I tighten the belt on my whole house fan?

Loosen the motor mountain bolts a little, suit motor until belt deflection is i-half inch per two-foot run. Then tighten bolts and check tension by running fan. No startup squeak should occur.

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When y'all use the whole house fan, you lot too clear out your attic of harmful moisture and heat build up, which will increase the functional life of your roof.
A whole house fan costs pennies an hour to operate, depending on the size of the motor. It's a toll-effective alternative to ac.
Keep screens on windows to prevent insect and debris entry.
Running the fan in an unoccupied abode wastes energy and money.
Screens volition require regular cleaning. The screens are the functional equivalent of air filters for your dwelling house when running a whole house fan. This volition require annual cleaning. Don't forget the screens in the attic infinite through which the air will belch to the exterior (such equally the gable vents). They will besides human action as filters for anything that volition no pass through, and over time, eventually reduce the menses of air to the outside.
Attic fans were common in the hot, southern United states before air conditioning. Air within the house was exhausted by a single powerful fan into the attic where information technology dispersed through the vents. This also cooled the attic. Open up windows would have an in draft. The fan racket would be in the attic. This can be emulated by propping open an attic stairway plenty to let a draft through roof mounted turbines or similar powered ventilators (if your abode is then equipped) without the stairway blocking its passageway. A simple box fan can be placed in a fireplace and framed with cardboard. House air volition be exhausted through the chimney.
Open windows only in the room you're in and save money by setting the fan speed to a lower value.

More attention to filters in your habitation will be needed due to the increased pollen, grit, etc being fatigued into the space.
It'southward not a skillful idea for people with allergies or asthma to employ a whole-house fan during spring, or any other fourth dimension of plant and weed germination. A sudden onslaught of outdoor air can wreak havoc on allergies. Check with your doctor first. There are filters that are bachelor for your window that you can buy to prevent such. Cheque operation of your gas powered hot water heater - if the whole-house fan is sucking the exhaust back down from the chimney, you need more than windows open.

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Commodity Summary X

To use a whole house fan, start by opening up any screened doors and windows in the room you'll be in. Avoid opening windows or doors without screens since they won't work with a whole firm fan. Next, shut the damper on your fireplace if you have one then that soot and odors aren't fatigued downwardly into your house. Finally, turn on the fan and so absurd air from outside is drawn in through the open up windows and doors. To acquire how to choose the right whole house fan for your home, keep reading!

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