Rear HVAC compressor and fan won't come on

[bobder41]

On my coach I have the thermostat calling for cooling on the 2 zones. The duct fan will start for both units and the front compressor. The rear compressor and fan will not start on the unit. I breakers are on since when I flip the rear one off its fan duct motor turns off also. My question is on a roof top unit with the ducted system how do you get to the junction box or controls of the unit. I'm pretty sure Coleman would not design a unit that would require removal from the coach to check it out.
Coleman heat pump Model 47073a879 13500 BTU

Thanks in Advance

[Peralko]

The capacitor on the unit may have gone out. Simple to change out on the rooftop unit.

[Dtwallace]

Originally Posted by Peralko

The capacitor on the unit may have gone out. Simple to change out on the rooftop unit.

And will not require removal of the unit

[Melmoses]

Go to the Airexcel/Coleman website if you don't have the manual for your ac. The parts diagram will show you exactly where to look for the start capacitor. The shroud comes off easily and these units are easy to work on. Just be sure no power to the unit is on when you do.

[Dutch Star Don]

"bobder41"....Before you go too crazy, do you have 30 amp or 50 amp service. Your coach won;t run both A/C's on 30 amps unless the conditions are perfect, like everything else is off. If you do have only 30 amp, try firing both units with the generator.

[asuperheat]

I think Don is on to something. Maybe just call for zone 2 and see if it will run then. If you have EMS it may be shedding the load.

[bobder41]

Thanks to all for the advise. I found a bad relay in the control box under the condenser fan motor. Calling the dealer today for a replacement part. The dealer is 300 miles away from my house.