AC and fan not working

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wdchparks

New member
Joined
Aug 11, 2017
Posts
3
I have a 2006 31' coachmen with a dometic roof top ac unit.  I started the generator and turned on the AC unit.  The generator suddenly began to groan like it hit a short.  I Shut off ac generator fine.  So I tried to turn on the fan, the fan does not run either and does not affect generator when I try it.  Going away in 4 days cant get in for service call.
If the capacitor is bad would it also stop the fan from working?
I will be opening up roof cover tomorrow battling hornets in it today.
I will see if fan spins freely, will I also see the inside fan up there?
I don't have a fancy capacitor testor but do have ohm meter what am I looking for?
Do I have to discharge it before testing?
I have also read that it seems all ac units mount to a 14 x 14 box so replacement seems to be some plugs and bolts.
 
Most of the time, defective capacitors will be bulging.....usually at the top where the terminals are.  (But. of course, you can have a bad cap with no swelling.)  You can disconnect it and look for an ohmeter "capacitive kick" but that's not much of a test.  Suggest you short the terminals together (just a precaution) and take a few pics of the wiring.  Then take the capacitor to a Graingers (hopefully you have one [or something similar] in the area) and get a replacement.  The rules: The replacement cap must have the same or higher voltage rating (it almost certainly will) and while the exact replacement in capacitance (ufd) is very desirable;  most manufacturer's reps agree that capacitance values within + or - 10% are acceptable.  A LOT of rooftop A/Cs are brought back to life with a new cap...........and you can use a spare anyway if that turns out not to be the problem.

BTW- It is highly likely that your fan cap and the compressor cap are integrated into the same "can"; however, it is just possible that the fan cap is separate.  If so........replace 'em both while you are up there.  Oh, and carefully clean the condenser fins if they need it too .... you'll be lookin' right at 'em.

Lots of experienced HVAC guys here on the forum ........ hopefully they will chime in.

If you have a lot of trouble finding a place to sell you a new cap, I would stop by a heating & air conditioning shop (in person) and tell them your predicament.....and they might "cut you some slack" ............ I know I would.

Good luck.........and safe travels on your trip.
 
Thanks, there is a Graingers not sure they are open on Saturday, I do have about three trailer repair places in close proximity.  I will replace both and hope for the best.
 
You can get upgrade or replacement start caps on Amazon & Ebay. Search for 'start capacitor' and select one designated for your a/c make & model.

But you may just have a bad or jammed fan.  It should spin freely by hand when the a/c is off.
 
Fixed
Issue was hornets nest built into fan, so fan could not spin. They must not have much torque.
Removed many bee nests cleaned up coils and unit.
Unit is now running fine
What I learned
The condenser fan is dual shaft motor, inside blower and condenser fan.
The AC unit tripped the breaker on the generator long before any breakers tripped.
That bees seem to love to nest inside of the Ac unit, they did not win the battle.
That everyone here is extremely helpful
Thanks to all!!! :))
 
Thanks for posting back........it's really appreciated.  Nice to have a "zero dollars" fix once in a while.  :D

Looks like Gary "nailed it"..............again.  :)

Be safe...............
 
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