Originally Posted by JamieGeek
Make sure the water heater bypass valves are set properly before firing it up. Especially if you'll use it on electric.
I forgot to mention, the Challenger has 2 water heater bypasses. There is the one on the termination panel in the storage compartment and then there is the standard three valve bypass close to the water heater. Both of the bypasses must be set correctly for the tank to fill. I opened the pressure relief valve on the water heater to ensure it filled before turning on the electric to the tank.