Last fall mine started overflowing and it water pump pressure related.  The internal coil wore thru due to age and vibration. I just bypassed the hot water coil and added a 4 gallon Bosch hot water electric tank until I could get back to my summer home/shop,  I pulled the unit this weekend and disassembled it. Thanks to it being in the middle of the coach the easiest way was to remove the cargo tray and rail then slide it out that way. took about 6 hrs to do. Mine has propane and the gas pipe ru