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squidflake
Dec 3, 2010, 08:30 PM
Having a problem with my blower motor. Even when you turn to fan on at the t-stat it doesn't kick on. After a while it kicks on after turning power on and off and spinning up the fan by hand inside the furnace. Could it be the capacitor? Not sure what it could be since the problem is intermittent.

T-Top
Dec 3, 2010, 08:49 PM
Its hard to say with out voltage reading. If you have voltage going to the motor and its not working you have a bad motor or run capacitor. You can take the capacitor to any local hvac company and have them test it. If it reads low buy one from them it's a very low cost item and give it a try. Its not uncommon for a motor and capacitor to go out at the same time.

ma0641
Dec 3, 2010, 09:15 PM
Sounds like a bad start capacitor. By turning the fan by hand, you help get the motor started. Capacitors are usually small round or rectangular boxes on the motor or squirrel cage ***'y. They are very inexpensive and easy to change, match the microfarads as close as possible. Make sure to short the capacitor terminals to ground before touching them in case they are still holding a charge. .

squidflake
Dec 6, 2010, 06:40 AM
OK. Thanks for the replies. So last night, the house was cold once again. Furnace fires up, but the blower does not come on. Turned the T-stat to "fan on" and nothing. Went to the basement and turned the power to the furance off, then on again. When I manually press in the door switch I hear the solenoid click loudly, so I assume that's working. Then for no reason the blower decides to come on without me turiing the cage (which by the way is turning very easily). Could the turning the system off then on again be doing something like charging to the capacitor? If the furnace went out on high limit, wouldn't the blower kick on and stay on? Shouldn't the blower start no matter what once the switch is turned to fan on. PS now that its running, I left it on fan on to keep the chill off the house.. Does this still seem like a capacitor issue?

ma0641
Dec 6, 2010, 07:30 AM
If the fan "turns on" when you spin it by hand or by bumping the switch it is most likely the capacitor. Once it is running, the capacitor is not used. Capacitors are charged from the line not the motor. For <$10 try the capacitor.

squidflake
Dec 6, 2010, 10:52 AM
THanks. Will change it out and let you know