Either fill the fresh water tank and turn on the pump, or connect a hose to the city water inlet. Then make sure your water heater is not bypassed for winter storage. Run the hot water taps at every sink, shower, outside shower, etc. until it stops sputtering air and you get a steady stream of water.
That fills your water heater, and it's now safe to turn on the heat. Turn on the electric heater first (connected to shore power) and let it heat for 10 minutes. Run the hot water and see if it's warm. If so, turn off the electric heat and turn on the propane switch. Go outside to the water heater vent and listen for the burner operating. If it's burning, you're good.
Be careful if it gets to full temp, I think mine is set to 140F. Probably not enough to injure, but it is plenty HOT!
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