How To Tell If My Attic Fan Is On

Whole house fans work on the principle of removing the hot and humid air out of the house.

How to tell if my attic fan is on.

If the fan turns on the motor is still good. If you re running an air conditioner you wouldn t want to have a whole house fan blowing that cooled air into your attic. Any whole house fan that you buy should have this figure listed somewhere on the packaging. The warm air escapes through the attic and to the attic vents allowing the circulation of chilly air from the windows.

Now take that number and divide it by 750. Once done test that the motor still works by plugging the motor into an extension cord that is connected to an outlet. Turn the attic fan off and unplug the motor from the thermostat. However the utility of attic ventilation fans is actually quite a controversial topic.

The downside of attic ventilation fans. Attic ventilation fans whether hard wired or powered by their own solar panels seem like a low cost and effective way to help keep your house cool. You simply add up the nfas of all your vents and divide that number by the area of the attic to determine whether you re within the 1 150 ratio. How to tell if you need an attic or whole house fan.

Your attic fan may not be turning on because of an electrical problem like a tripped circuit breaker a blown fuse or a bad connection. When the temperature within the attic reaches a set point the fan will turn on and start venting the heated air cooling the attic space. Likewise adjustable thermostats will shut the fan off. The whole house fan is installed inside the attic between the living space and ceiling.

Or look at the weather for 2 days with the same weather and monitor temps with and without the fan on each day. You can diagnose it by plugging other electrical appliances that are working into the same outlet and by plugging the fan into a different power outlet. So if your fan is rated at 1500 cfm you will need about two feet of totally open space in your attic. Turn your fan off and monitor the temperature in your attic up unitl 2pm or something then turn it on.

Good insulation reduces fan effectiveness. This is done because you need one square foot of ventilation area for every 750 cfm that your fan can push.