2nd A/C

[huntram]

So my buddy who has worked on RV's for over 30 years (If you have seen RV Today on TV you have seen Bill), says in all his years he has never seen a coach that allowed both A/C to run off 30 amp UNLESS there was a switch between them. He is really questioning this. Help me, to convince him. So are you saying without switching something I can choose either the fromt or back A/C to run while hooked to just 30 amp? It doesn't really matter to me, but Bill who has a HH and is now retired and fulltiming doesn't beleive it. I keep trying to convince him 

Thanks!!!!
Brian

[gtfiver]

I'm not an electrician, but here's how I understand it. The 2 A/C's are wired on different circuits. When you are conected to a 50A service, these two circuits are powered separately and you can run both A/Cs at the same time with no issues. When your are connected to 30A service, the adaptor bridges the two circuits together so that they are no longer powered separately. What that means is that in most cases, you can't run both A/Cs at the same time without tripping a breaker. However, you can run either the rear A/C or front A/C, your choice. You just turn one on and turn the other off. Hamshog is saying that he was able to run both A/Cs at the same time on 30A without tripping a breaker, but his fridge and water heater were turned off while he was doing that.

[Hamshog]

Hey Huntram(Brian),

     Like GT5ver said, while on a 50amp 2pole circuit, the A/C units may be on separate phases or not. With the A/C units drawing 11 to 13 amps while running(2 units would be 26 to 28 amps), and 16 to 19 amps on startup, the 50amp 2pole circuit has tons of power. When you put a 30amp adapter on the 50amp coach cord, the adapter bridges the 2 phases of the 50amp, and makes it a 30amp 1pole system.

      Now amps and volts are directly proportional to each other. The more volts you have, the less amps it takes to run the same load. While running both A/C's on a 30amp 1 pole circuit, I had 125volts of push, so my amps were lower,(approx. 26amps) even with both A/C's on. Had the voltage been 110volts or lower, I'd have added 2 or more amps to the circuit, which may not have held the load.

      Tell your buddy it can and has been done with no problems. I can't be done everywhere, everytime, but with the right conditions, yes...

Regards, Hamshog