Water heater running on electric power is the most common reason for a 30 amp breaker to trip in my experience. The water heater draws a lot of amps, and you have no control of when it kicks on.
Otherwise you will learn quickly not to run two high power appliances at the same time.
Most folks can actually run two ACs at the same time. The high power draw is only when the AC compressor starts. Once the AC is running the amps being used drop down. But as with the water heater you must manually control when the compressor starts. You cannot run the AC on a thermostat.
I routinely fire up both ACs on 30 amp power when we arrive on a hot day and the inside the rig is like an oven. But EVERYTHING else is turned off. I power up the bigger AC and let it run a couple minutes to stabilize the power draw, then turn on the smaller AC. If the breaker holds the load, fine.
But I only run them in the ON mode, not automatic. And usually only a hour or so. And I can’t use any other 120v appliance.
Full-Time 2014 - ????
“Not all who wander are lost.”
"You were supposed to turn back at the last street."
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