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Need help to fix slow running Air conditioner motor? Answered

The motor in my central air conditioner runs slow. I have replaced the control board but motor is still slow. I checked the motor by directly connecting it to a power source and it operates at normal speed. It's only when I connect it to the control board it runs slow. What is causing the motor to spin slow?



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1 year ago

Can be many things but if it runs fine directly it only leaves your air conditioner system.
If it is running quite rough and at about half speed I suspect it is only getting one half of the sine wave.
Maybe a faulty filter on the board or motor control.
If it is DC motor or otherwise speed regulated motor then the corresponding tansistor(s)/mosfet(s) that regulates the motor speed could be faulty.
Hard to say without poking it with my multimeter....