My a/c is not working. The fan is blowing air but it is not cold air. It seems that the condenser fan is not kicking on when it is supposed to. We thought that it was the motor, because it would turn some, but slowly as if the bushings inside the motor were bad. Well, I got a new fan motor, installed it, and it is still not kicking on. I don't know what to do... Please help!

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Originally Posted by bhenson7

My a/c is not working. the fan is blowing air but it is not cold air. It seems that the condenser fan is not kicking on when it is supposed to. We thought that it was the motor, because it would turn some, but slowly as if the bushings inside the motor were bad. Well, I got a new fan motor, installed it, and it is still not kicking on. I dont know what to do.... Please help!

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Can you hear the compressor running? Did you change the capacitor when you changed the motor? Are you sure it is wired correctly?

How much vlotage do you have going to the fan motor? It could be the points on your contactor, it could also be shorted compressor that is feeding 120 volts to your fan motor and that could be what is making it turn so slow. It is always smart to make sure that the motor is bad before replacing it.

It sounds like your original problem may have been the capacitor. Are you sure the new fan motor is wired correct? If so I'd replace the capacitor.

There are many things that could cause your fan or unit not to run. As mentioned before, does your compressor try to start? If you have a good unit, it probably has a low pressure switch that won't allow the unit to come on unless you have enough refrigerant in the system. Sometimes there's just enough refrigerant charge to allow it to come on for a short period or until the suction side of the system drops down low enough to shut if off. It will help if you can give us an up-date.

If the fan is slowly turning I wouldn't think that would be a freon issuse

They also said "it seems like the fan isn't kicking on when it is supposed to" which can be caused by a open low pressure switch...

An open low pressure switch would break the low voltage and the unit wouldn't do a damn thing...

"THE FAN ISN"T KICKING ON WHEN IT SUPPOSED TO" then they replaced the motor and and "IT IS STILL NOT KICKING ON". Means it may not be coming on at all which in turn MEANS IT COULD BE LOW PRESSURE.

"My a/c is not working. the fan is blowing air but it is not cold air. It seems that the condenser fan is not kicking on when it is supposed to. We thought that it was the motor, because it would turn some, but slowly as if the bushings inside the motor were bad. Well, I got a new fan motor, installed it, and it is still not kicking on. I dont know what to do.... Please help!" From what I read it also says the fan would turn slowly, Yeah you're right, it could be low pressure, it also could be about 5 other things , I was simply trying to give the guy some other ideas... just what the world needs another ing KNOW IT ALL SERVICE GUY!

I was the one who just SUGGESTED that it COULD BE the low pressure switch. I was the one who was just giving another possible ides... YOU said it can't be LOW PRESSURE I don't pretend to be a know it all service man. But I'm here to offer any SUGGESTIONS to people who need help. I don't do service work anymore, but I have many many years experience with industrial & commercial HVAC & refrigeration. You have a good day!

I agree with the run capacitor idea. At first the motor will run slow and at times run backwards and then not run at all (do to over heating)If the capacitor is bad. If you got a new motor it may not be rated for the old capacitor you have. Just because you changed a 1/4 hp for a 1/4 hp motor does not mean it will take a 5 mfd capacitor.

I agree, that's where he needs to start anyway

My split system is doing the same thing; i.e. when turning on unit, fan moves slowly and finally has got to where it will not speed up and permit functioning ac. Compressor amp draw is right at 28 amps and steady; fan amp draw is a steady 3 amps. High heat build-up in a couple of minutes from condenser!

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Originally Posted by hvacservicetech_07

An open low pressure switch would break the low voltage and the unit wouldn't do a damn thing.........

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What if the low pressure control was self resetting---would it do anything?

If compressor is running while fan is not running the problem is most likely the fan motors RUN CAPACITOR. Check fan motor run capacitor. This run capacitor may have two terminals which is a dedicated capacitor for the fan motor. The capacitor may have three terminals which is a dual section run capacitor that operates fan motor and compressor motor.