Running 2 a/c's

My opinion would be that if the generator wont run two just run one. I sure hopes this helps.

If connected to your camper, you might be exceeding the generator's capacity because: the water heater is on electric, the microwave, television, refrigerator on electric, and radio in your camper could be pulling parasitic power when not actually turned on. The converter in your camper is running, charging your batteries. Add it all up together, and might not be JUST the air conditioners pulling the load, but everything else in your camper combined with the 2 air conditioners that is exceeding the limits.

total power use
and
the a/c units might benefit from "soft start" kits (generally listed as Hard Start)
added to the compressor start up circuit, they reduce the surge load on the generator

13k btu a/c has a compressor lock rotor AMPS surge of about 54amps
so if the running loads a/c etc total 20amps
and the second a/c needs 54amps to start the compressor spinning, your asking that 5000w genny to provide almost 10,000 watts for the few seconds it takes to get the compressor running
the compressor can't get enough power it just overloads the genny
the first one starts, because until you start the first compressor there is very little load and the genny and Grunt and get the first compressor running
but it doesn;t have enough ommph to do both

this is more about the age of the A/C components needing more power to start since they are getting older, not the generator, it was sufficient when everything was NEW

We had the 5500 Onan on a 2002 MH with two AC's. Dont remember if they were the 13 0r 15000 size and it had no problem running both at one time. Didn't have an elec water heater. I'd say your Onan needs a tuneup.

Unpopular comment coming: Presumably you're boondocking and want to run 2 AC's? Perhaps you need to seek an alternate hobby/lifestyle.

Our 5500 Onan runs 2 13.5K A/C units with no issue I would get your genny looked at.

I would check how your A/C is wired in your electric distribution panel.

I have had two RVs where both A/Cs where on the same leg. This stupid wiring error by the manufacturer made it such that it would stall my Onan 5500.

Moved the second A/C to the opposite leg on the distribution panel and all was well from then on out.

noplace2 wrote:
Unpopular comment coming: Presumably you're boondocking and want to run 2 AC's? Perhaps you need to seek an alternate hobby/lifestyle.

Don't editorialize. Just stick to answering the question.

Do you have a 30 amp or 50 amp system? I have a Kohlar 5500 watt genset with a 50 amp system and when I turn the second AC on it bogs down for a few secs then runs ok. Is your frequency set to 60 HZ?

How old are these 13.5 air units? Yes have the start capacitor checked by a good technician... and good luck finding one.

Otherwise the best shot is to buy a new nigh efficiency air conditioner.