Generator Will Not Run AC

[Bob Rivers]

2003 36LD Horizon,
New basement AC unit (2 compressors), Same issue with old AC unit.
Well maintained Onan Diesel Generator
AC runs without issue on shore power.

Problem:  Generator turns off when AC is running.  It does not rev up or bog down under the load, it simply turns off.  The generator will restart immediately, run for a few minutes then shut down again.  Any suggestions?

 

[Isaac-1]

You likely have one of 2 things going on, the air conditioner is pulling too many amps (may be a bad capacitor), or the generator is not adjusting to load.

 

[John Hilley]

Sounds like a generator problem. You can test with electric space heaters and microwave to see if it does the same thing.

 

[John Canfield]

What John said. Is your generator an inverter model (speeds up and slows down according to load?)

 

[Bob Rivers]

Not sure, but it does speed up when under a load (speeds up when coffee is brewing).  It does not speed up or bog down when it shuts off when only the AC is running.

 

[Bob Rivers]

John - I'll try using heaters and the microwave soonest.

 

[Gary RV_Wizard]

Both types of generator increase engine power when under load, but only the inverter type actually changes rpm. The other type is applying more power to maintain  constant rpms. It may be hard for a non-tech novice to tell the difference.