The original, and two replacement, fan motors in the outside (compresser) unit of my Miller central air conditioner system all made a loud noise when wet. At first, I thought it was a bad motor, but a replacement didn't help for long. The second replacement worked a day, but the next day was very noisy.I finally traced the problem to one of design. The motor is open in the bottom. When it rains, water hits the fan under the motor and gets splashed up and into the motor. When there is water in the motor, it gets extremely noisy, sounding like a diesel truck motor.There is no question that this is the problem. On a dry day, when the motor is quiet, if I spray water up into the motor (yes, I switch it off first) and then start up the unit, the motor gets noisy.Can I simply replace the motor with a sealed unit of the same power, shaft size, RPM and rotation and solve my problem?Has anyone ever seen this problem before? Is there an easier fix?
Sometimes when the compressor is wet, the fan is pulling on the moisture and it is working harder and may sound a little different. That would be normal. But if it is real loud, may be time for a new one. If is more than 12-15 years old, you will have a new one about twice as efficient.
yes i have seen this problem and it was because the motor wasnt the proper motor for the unit.. nearly all condenser fan motors are totally enclosed..or on some old units if the motor had openings on the bottom of the motor there should have been a water slinger that was larger in diameter than the motor to prevent water from being blown or splashed into motor....the easiest fix is to buy a water slinger and install it between your fan blade and your motor...
A condenser fan motor should not have a open frame. It should be a closed frame motor. To answer your question, yes you can relace the motor with a closed frame motor. Make certain the replacemsnt is the same frame size, rpm, horse power and rotation. You will also need a matching capacitor for the replacement motor. Before removing the fan blabe mark on the blade how far down it is located in the condensing unit. A fan blade which runs too deep will draw more amperage than the motor is rated for and it will also cause the head pressure to increase on the compressor
