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Lazarus_Alessan's avatar
Jun 21, 2019

Replacement AC fan motor very weak.

Short version: I just replaced a failed AC fan motor. Now the fan actually works BUT it runs at around 20% of the previous speed and blows air very weekly. Also, when I set the fan to auto instead of low or hi, it doesn't blow at all. Help!

Background: I've got a Dometic 13.5K BTU ducted AC in my 2014 Coachmen Apex. A while ago the fan started having a very hard time turning on (click and hum but no turning even if I tried to spin it by hand) but after trying for a couple hours if get lucky and it would start. Once it started, it would run indefinitely. I replaced the capacitor and that didn't really help. Yesterday, I got it running after a struggle and it ran for a few hours until it started squealing louder and louder until the fan geadually slowed to a stop. I got a replacement for my model (457915.711CO) from an RV service place, same size, wire colors, wire lengths and connectors so I felt confident it was the right part. I installed it and now I've got the problem I mentioned above. Could it be a bad ground? Did I swap a wire? Anything? O was only 95% sure that I put the condenser fan back on the right way but that doesn't seem like it should me such a drastic difference in the speed the motor will turn. Any help is appreciated.

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