air conditioner fan sticks

[jmatt]

HELP! HELP! has anyone had to climb on top of their Montana 5th wheel to start the fan on their air conditioner so it would run. Otherwise, it humms and does nothing. If it sits for a few weeks without using it it sticks and has to be started then it runs until it isn't used again for a few weeks???? HELP! PLEASE. jMATT

[waldo238]

Sounds like the motor is bad or a bad starting capacitor if it has one.

[Les and Julie]

It does sound like the capacitor is malfunctioning --- it is probably burned out.

Les

[Ozz]

I have had some luck using a spray of WD-40 on each end of the bushing/bearing bell, then rotating it by hand. It takes very little resistance to stop them from turning. Could be the half of the capacitor that is used for the fan motor, (the other half is for the compressor) *** (in most cases.) I have lengthened the service of motors by drilling into that bushing/bearing bell and injecting some light grade oil. There is usually a fiber packing that holds the oil.
I don't know if your fan has bushings, or bearings. One would hope bearings.If you need a capacitor, get the numbers on it and call your local Johnstone Supply Co. they will have it.
Ozz
Good luck.

[Ozz]

http://www.grainger.com/Grainger/cat...ies/capacitors

[racerjoe]

Mine was stuck last spring,the first time I turned it on. Had to go up at move it by hand also. Was ok after that,do not know about this spring yet. Ozz is right,I think it is a lubrication issue also,if it happens again I am going to lube it as Ozz suggested,The older GM cars and trucks used to have a fan motor with no shut off,always on low speed,after a while they would stick or make a growling noise. You would drill a small hole in the rear of motor and shoot some WD40 in there,to quiet it up and make it work right.

[Ishler]

I had the same problem with ours, I called Dometic and they replaced the motor. Apparently they had a bad batch of motors.

[Dogman]

Ours does that occasionally. Next time your topside remove the shroud and spray the fan shaft with a silicone spray (WD-40 attracts and holds dust and dirt). The problem usually is a buildup of dirt/dust which is just enough to cause the fan to stick when the AC is started. Once you clean and spray the shaft you shouldn't have any problems for quite a while. Also, when and if it does stick you can (at least on ours) access the fan from inside by removing the main ceiling grille. You can see the fan and all you have to do is reach up and give it a spin (make sure the AC is switched off). That will free it up and then when you turn the AC on the fan will start turning.

[Ozz]

In winter, when in cold weather, and not using the A/C unit, I advise turning on the INDOOR FAN ONLY of the rooftop unit, this will keep the fan in working order. Once a week or 2 weeks, It is not good for it to sit idle for a season.
DO NOT TURN THE A/C unit on, (compressor) in Winter.... not good.