Furnace Blower Motor Capacitor Test

First the power supply should be shut off then the two terminals on the capacitor should.

Furnace blower motor capacitor test. Remove the wires that are connected to the terminals. If you re concerned that your furnace capacitor isn t operating properly you can test it by following a few simple steps. Set your voltmeter to the capacitor. I dont know how savy you are.

Although only pros should test or repair capacitors you can examine your. Buy when you get up there there are a couple of wires coming off the blower motor. Look at the wiring digram on the back of the furnace. How to test start capacitors on furnace blowers.

Check the capacitor rating on the side of the unit. Failed capacitor would be my guess if no blower. Excessive heat in the motor can cause the motor to malfunction. A furnace usually uses a run capacitor to maintain a relatively constant voltage supply to the blower motor.

Inspect the capacitor visually for signs of damage. If it not you probably have a failed capacitor. This will cause the motor to run slowly causing excess heat. Check the capacitor rating on the side of the unit.

If the capacitance number went up infinitely to the limit of your multimeter the capacitor has shorted out and should be replaced. The capacitors on most of residential blower motors are very small so technicians tend to overlook them. So the capacitor plays a big role. When the motor generally goes south the motor itself it will trip the breaker.

Locate the capacitor inside your appliance capacitors are metal tubes that store an electric charge usually found near a motor in the appliance. Inspect the capacitor visually for signs of damage. For example if your capacitor says 50 5 the acceptable capacitance range is 47 5 to 52 5 f. A capacitor helps the motor run and gives it more torque.

Some capacitors will have a set capacitance with an acceptable percentage of variance. How to test start capacitors on furnace blowers. If you notice your furnace s motor cycling frequently you should test the capacitor. A faulty capacitor will not be able to hold the charge necessary to run the blower motor properly.

Using a capacitor tester to test the capacitor. Set your voltmeter to the capacitor setting and connect the meter to the terminals on the capacitor.