Originally Posted by wildpop
NO the dealer did not show me. They did a basic walk through and nothing more. I found nothing on the back of the wqater heater no switch, no nobs nothing.
Here's the key to the forest! I had the same problem 1st night out. The only access I know of to a wtr htr in 378 is through a 3" white screwed plug just under the access door. Unscrew it reach up in the the back of the heater and your'll soon realize which is the bypass valve. Inlet at bottom, outlet at top and bypass in the middle all towards front of coach. Close it, make sure other two are open, it water will now fill heater and you can start gas or electric.