Duotherm front ac wont start

[Gary RV_Wizard]

Is it possible for the generator to create only 1 phase?

The prior owner said he just replaced the inverter. Could it have been installed incorrectly?

Yes, and the Onan QD 7500 in fact does that, i.e. produced two legs with exact the same phase. But your EMS recognizes that special situation and handles it - notice that the EMS display indicates power is coming from the generator. Your EMS display also indicates it is passing power to the front a/c, so it is not intentionally shedding that load. That too shows it thinks you have an adequate power source.

The most likely conclusion is a bad relay for the front a/c power or a faulty front a/c breaker.

The inverter is not involved in power to either a/c, but it's conceivable the installer could have messed up some other wiring. Not likely, though.

 

[Vin2]

Yes, and the Onan QD 7500 in fact does that, i.e. produced two legs with exact the same phase. But your EMS recognizes that special situation and handles it - notice that the EMS display indicates power is coming from the generator. Your EMS display also indicates it is passing power to the front a/c, so it is not intentionally shedding that load. That too shows it thinks you have an adequate power source.

The most likely conclusion is a bad relay for the front a/c power or a faulty front a/c breaker.

The inverter is not involved in power to either a/c, but it's conceivable the installer could have messed up some other wiring. Not likely, though.

I am almost certain it is a faulty relay within the ems board. The front ac works now that i have it jumped.

These parts seem hard to find. It will likely stay this way for the foreseeable future

 

[8Muddypaws]

There are probably techs around capable of doing a board level repair. I probably know one but I'm in the SF Bay Area.