I have a 2015 2502KS. I run all 3 on occasion on a 30 amp service.. I don't notice anything funny. Everything seems to work just fine. I have a 15,000 btu AC. The fridge is your standard nonresidential RV fridge runs on gas and electricity. Even still the lights don't even dim. the water is very hot!
id be checking the voltage regularly...if you get below 110, id drop the WH. it will shorten your life span on appliances and melt down connections eventually
Run the fridge on propane, in my experience it works best on propane anyway. Water pump does not pull much.
Trailer: Lifted 228BH, heavy duty springs and Yokohama tires TV: 2016 GMC Sierra Z71 4x4 CC, SLT
Spare TV: Two Alaskan Malamutes
Living somewhere in ID; previously lived in Moab UT; previous to that, don't ask!