Testing An Attic Fan

Switch off the power of the attic fan and remove the power cord.

Testing an attic fan.

Look for movement of the needle on the meter toward infinite ohms. Reverse the leads on the capacitor. Also note down the power rating and the fan capacity in cubic feet per minute. Step 1 test the fan motor.

Inspect the attic if your attic is not sufficiently vented you probably won t have to look very hard to find signs. Step 2 test the thermostat. Turn the attic fan off and unplug the motor from the thermostat. Count to three while the leads on the meter charge the capacitor.

One static vent style is the turbine vent which uses wind to power its enclosed fan all it takes is a light breeze to rotate the blades and suck heat out of the attic view example on the home. Note down the wiring before proceeding to remove it. You may need to replace a circuit breaker an electrical outlet or one of the wire connections. Place the leads of the ohm meter on the wires that run from the capacitor to the motor.

The cause of the problem could be the belt. They include rafters and ceiling joists that are damp or blackened with mold. It is preferable to do this test without the moving blade. Once done test that the motor still works by plugging the motor into an extension cord that is connected to an outlet.

Place the black probe on the white wire. Locate the thermostat casing and open it using a screwdriver. If the attic fan is plugged into an outlet use a voltmeter to make sure that the outlet is working. You ll need to take out the outer casing of the fan and look to see if the belt is cracked sagging worn out or broken.

Fan motor runs but not the blades if the motor is working but the fan blades are not moving the problem may be the belt. If the fan turns on the motor is still good.