[Richard and Rhonda]

This is what I have learned so far, just in case you have to investigate a similar problem in your coach.

The main control board for the Dometic units is usually located in close proximity to the evaporator (the unit inside the coach) For my front unit, the evaporator is right by the door, underneath the kitchen counter. When I removed some of the internal pieces of the cabinet, I found a small box with the control board inside. On the control board is a relay the provides power to the condenser unit. This relay is not "making". When I bypass the relay and hardwire power to the condenser, it works as it should.

Here are some other useful bits of info.

My Dometic systems are filled with R22. I took these measurements at about 55 degrees ambient. The static pressure in all three units was about 90 psi. When running the high side was about 150 and the low side about 45.

I have to find a replacement board now.