A/C (Heat Pump) Help Requested

[hrgeorge]

The rear unit (Zone 2) in my MH has quit blowing cold air.

I’m a pretty handy guy and like trying to fix things myself, but I don’t have a lot of experience with HVAC. I’m fairly certain this is an electrical/electronic problem though I haven’t even taken off the outside cover to look for anything obvious.

The unit was working fine as we headed out on or current trip. We even used it with the generator at a stop along the way. Since we parked and hooked up to 30 amp power, the normal “power shedding” hasn’t happened. Zone 1 works fine. Zone 2 comes on but does not cool. The compressor doesn’t seem to be running. I’ve checked the obvious (breaker, cleaning, inside wiring connection and thermostat). By checking the thermostat, all I’ve done is make sure it comes on and goes through all the settings properly and it is operating the front unit, Zone 1, with no problem.

I’ve thought about just trying the “shotgun” approach to changing out electrical components to see what helps. But, I know there are problems with that (including lots of expense, some can not be changed easily, may actually be compressor or something else this approach won’t fix) and hope that someone can help me diagnose this properly. Plus, I haven’t opened the outside cover on the Control Box, but I’m already having problems even looking up parts.

Some specifics: Unit is in a 2005 Fleetwood Bounder 37U DP but may not be original (I know the Thermostat has been changed).
The Model Number I can see on the bottom from the inside access is
8534B8767
The numbers I can see on the outside of the Control Box are: RV00293

Again, I don’t know that the control box is an issue, but so far I haven’t been able to locate a board with that part number.

Any help diagnosing will be greatly appreciated!!!

Also, I may be putting the cart before the horse and don’t want to spend this much - But, if I do need to replace the whole A/C (heat pump) unit, how can I find appropriate replacement models? Wired the same using same wires from thermostat with same color or other designations? Do I need to by one with heat strips or can that be moved from my current unit?

Thank you in advance so much for any help you can give!

[mdewenter]

Harry -
I can't help you with diagnosing the issue with your A/C unit; but I looked up your model number. It's a Coleman®-Mach 3 P.S.™ Heat Pump; they've updated their part numbers, new part number is 48008-966.
Mike