A/C breaker trips

[Pete Masterson]

When the compressor cycles on, the AC can (very briefly) draw well over 20 amps. Most circuit breakers are able to ignore the transient draw -- so I'd suspect a bad breaker that's too sensitive.

As for shore power with 15 amp circuit, I would expect the breaker to trip almost immediately. The standard rooftop ACs draw 14+ amps normally and _any_ other load (lights, battery charger, water heater electric element) will put you way over the top. It's hard enough to keep the AC (and other typical loads) happy on a 30 amp circuit.

Go buy a 12 gauge extension cord. A "skinny" cord is probably dumping a lot of energy as heat instead of delivering it to your coach -- and it's a dangerous fire risk. Look at "contractors" extensions in a home center for a 12 gauge model. Get a cord that's as close to the actual length you need as extra cord will reduce the electrical efficiency.

Pete Masterson

'95 Blue Bird Wanderlodge WBDA 42

El Sobrante CA

"aeonix1@mac.com"

On Jun 29, 2008, at 12:15 PM, John Churchill wrote:

Well, I just got my generator started for the first time ever.  Onan

7kW with a 20 amp and 30 amp breaker.  When I turn on the forward A/C,

it runs for a while (a couple of minutes), then trips the 20 amp

breaker, even with everything else switched off.  When the AC is off,

the breaker does not trip.  I have only used shorepower on a 15 amp

circuit (with a long skinny cord to boot) and it trips that too,

although I am not sure that is a good test.  The owner's manual says

that unit ought to draw 14 amps.  I understand there is a much bigger

transient load as it cycles, but shouldn't it be able to handle that?

 The rear A/C unit does not seem to run, so nothing to report there. 

Any ideas of what to do or check?  Thanks.