"Did you encounter any problems on your holiday trip to cold country, Dave?"
"It got kind of tough after a system failed. We had to heat water for tea in the microwave oven because the hot water dispenser quit working." :P
Our coach has a 12VDC/120VAC hot water dispenser. The 12VDC portion failed. A notice on the dispenser indicates that there are "No User Serviceable Parts Inside." I pulled the fuse at the foot of the bed that serves the dispenser. Then I pulled the covers to reveal the mysteries beneath. I used a continuity tester to verify that the heating element was intact, but the thermal fuse had opened. I ordered a thermal fuse for the Emerson/Insinkerator dispenser from Sears. I installed the thermal fuse and got 150F water from the dispenser while operating on the 12VDC circuit. I plan to adjust the thermostats to the minimal temperature that seems satisfactory for brewing tea or coffee.
I have included a few pictures so you can see what is under those covers that enclose the parts that are not to be serviced by the user. The thermal fuse is the little tubular gadget between two spade connectors at the upper right. There is another thermal fuse for the 120VAC circuit at the lower left. The picture of the plastic bag shows the part number. One could probably find a thermal fuse locally if you know the proper specification.
Interesting! Mine has never worked on 12v from the switch, but I plug it into 110 and it operates fine on AC. I will have to take another peek at it... I figured it was just an internal relay.
Dave, J. D. Later models after about 1999 did not have the 12v option. I had combo units in my '94 and my '95 but my 1999 and my 2003, neither had the 12v source. Wonder J D if yours might be a replacement unit?
I think ours is original. The coach is a 1997 model built in late 1996. I searched for the exact same dispenser on line and could only find the 120VAC systems. That is consistent with your experience. I assume the thermal fuses are the same for the 120VAC and 12VDC heaters. The 12VDC system has worked for a few hours now. I think it is fixed.
Our dispenser is wired such that the 12VDC portion will operate whenever the 12VDC house supply is turned on. The 120VAC portion only operates on shore power or generator power. The LED at the control switch for 120VAC will remain on under inverter power, but the 120VAC circuit is not powered from the inverter.