Condenser Motor Reverses After Each Cycle.

[dman777]

I have never heard of this one. Hope you guys can help. My current home is under a home owner's warrenty so I had a HVAC repair guy come out and replace a burned out motor on the condenser. When I got home I saw that the motor was drawing air down into the condenser and blowing it out through the coils. (Reverse from what it originally did.) I thought that the guy had just reversed the wires on the capacitor. Since it is a weekend the guy has not come back but I have noticed that each time the system cycles the condenser fan reverses. One time it is drawing in the next time it is blowing out. What is going on?

Thanks.

[Freon]

You need a new run capacitor for that specific motor. I have a feeling the repair guy used the old dual capacitor that was there. Since most condenser units use dual run capacitors (2 capacitors in one can, 3 connections at the top) for both the compressor and fan, it means a trip to the supply house for the right one and he was too lazy. Your old motor may have been fine since the reverse spin is a classic symptom of a bad run capacitor.

Make sure you know exactly what microfarad value you need for that fan motor. It may be on the motor case. The wrong capacitance value can burn out the motor or not give the condenser enough air flow.

[dman777]

Thanks Freon!

So a bad capacitor will make the fan run in reverse one time and then forward the next?

[Freon]

A bad capacitor can cause many weird motor behaviors. Since you said it ran clockwise one time and then counter clockwise the next, that's the clue it's a capacitor and not an improper motor with the wrong direction of rotation. Fortunately it's an inexpensive part, about $15, and very easy to install. Just make sure you pull the disconnect to the condenser unit and mark the leads as you take them off the old capacitor, assuming a dual capacitor with 3 terminals at the top.