Hello.
I have an older central Lennox furnace/air conditioner unit that has been giving me trouble lately. I noticed one day that the blower should have kicked on. I went downstairs and found the motor to the blower was humming but the blower was not turning. I flipped the switch on the unit on and off a couple of times and it started.

A couple of days later it happened again. I flipped the switch and nothing happened. I twirled the fan and it kicked in (this may have caused it to work or not----as I will explain). Working fine once more.

Yesterday it happened again. This time the switch method did not help. The twirling did not help either. But, I smacked the fan cage with my hand and it started.

My first thought was the capacitor. I took it off and had it checked. It has a rating of uf 5 and the tester showed 6. Should be good. Right?

So now I am stumped. The blower runs great when it is going. No squeak or rattle. Just having trouble getting going. Sort of like me now days. Anyone got any ideas?

Thanks ahead of time. I appreciate it.

:confused: :confused: :confused:

Sounds like the early stages of motor failure. Loss of starting capabilities with a presumably good capacitor usually indicates a "dead spot" in the motor windings. If your thermostat has a fan selector switch, set it to the "on" position for now to eliminate cycling the blower-this may buy you some time. I would recommend replacement of the motor and capacitor as a permanent solution.

Also if you are trying to buy time before replacing it try cleaning the motor cage.Sometimes excess dirt will slow down your fan and make the motor pull more amps than it is suppose to and burn the motor out faster. Unfortuantly it sounds like it already started.