The hair dryer will always do it!
I think your rig may have the
load shedding device which I believe kills the aqua hot electric water heater element first, not sure what's after that.
We don't have that device, and the last 30A park we are at in the heat, we shut off the aqua hot electric, dialed back the Magnum Shore Power setting to 5 Amps and turned off the Humidity Control on the fridge. After that we were able to run two AC's and the other low draw necessities reliably (but not the hairdryer) without popping the pedestal breaker.