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Topic: Roof AC won’t run on generator (Read 458 times) previous topic - next topic

Roof AC won’t run on generator

90 Grand Villa, 36'. We were driving and stopped to start the generator and the AC's. Generator started right up and the turned on the AC's which immediately started cooling and then continued the trip. About 10 min later noticed that the AC's stopped working.  Didn't have time to troubleshoot but when we plugged into shore power, AC's worked perfectly.  I flipped the circuit breakers on and off as well as the main breaker outside the panel.  Disconnected shore power, started generator but still no AC. Flipped all the breakers again, nothing. How do I check generator output?  What else do you suggest? Can the auto transfer switch from shore power to generator be at fault?  Where do I locate it?  Thanks!
1990 36' U280 Grand Villa
Cat 3208T/Allison MT643

Re: Roof AC won’t run on generator

Reply #1 –
It could be the transfer switch.  No idea where it is located on your coach.  I would guess that your generator also has CBs on it if it is like ours.  Did you look for and check those?

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: Roof AC won’t run on generator

Reply #2 –
What generator???

What did your AC voltage read when the A/C quit???
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Roof AC won’t run on generator

Reply #3 –
Check the breakers on the generator.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Roof AC won’t run on generator

Reply #4 –
Thanks for the input-examined the generator (7.5 Onan) more closely and saw the breaker on the left side at the back and it was thrown- so flipped it back. Embarrassed to admit I hadn't noticed that breaker before today. Anyway, fired up the generator and the AC's worked perfectly.  Didn't have time to do a long run of the genset to see if the breaker trips again.  Will do that soon. Thanks again!
1990 36' U280 Grand Villa
Cat 3208T/Allison MT643

Re: Roof AC won’t run on generator

Reply #5 –
It's best to replace that 30 year old CB on the generator.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R