Running Two ACs on Gennie - Shutting down

[Lakejumper]

Hi, I’m running my 5500 Watt Onan gennie with two ACs on while driving due to very hot weather. They both ran for several hours and all of a sudden they shut down and the control panel beeped with the gennie still running. It eventually reset itself. This happened several times. We had a full tank of gas. I had the gennie serviced recently. Why is this happening?

[Lakejumper]

I think that I know what happened. I failed to mention that I was in the high Sierra mountains at about 6000-7200 feet when this occurred. I believe that the Power Management System did a “load shed”. The manual states that the AC’s use at least 2400 watts when starting up. I have a 15k btu in the front and either a 13.5k or 11k in the rear. The manual states that the 5500watt gennie loses 3.5% power for every 1000 feet gain in elevation. Thus, I was losing about 23% of the gennie power. It couldn’t keep up with the ACs. This has been a good lesson.

[Lakejumper]

Thanks for the replies. The gennie kept running. I think the time2roll has the answer. It seemed like a load shed. The water heater was off and the fridge was on propane. I also thought that since I had the AC fan on high, both units may have coincidentally started at the same time so one shut down. It happened about three times during the last part of our trip during the hottest part of the day. We were also climbing at high elevation over 6000 feet. Perhaps the gennie surged. I’ll look at the manual.

[time2roll]

Control panel beeped? Is that an energy management panel? Could it be a load shed due to the water heater electric element coming on?

Did both A/C shut down together?

Self reset does seem odd unless something sensed an overheat condition.

[Yankee_Clipper]

There are a few auto-shut-off features, thermal, and low-oil are the most common tripwires. IN the heat, the fuel can vapor-lock. Check the airflow over the genny, another concern.

[way2roll]

pianotuna wrote:
It may be that the generator is overheating and shutting off to protect itself.

That's what I thought too but the OP said that the AC's shut down and the genny kept running?

To the OP, when it happens you need to get the code from the genny and it will tell you what the problem is.

[pianotuna]

It may be that the generator is overheating and shutting off to protect itself.