quikduk, it should be the electric water heater switch. The tanks should be heated from the furnace ducted into the area. Start with cold water inteh water heater; turn on the switch an wait about 30 minutes then check hot side of faucet. Be sure the switch on the lower left corner on the outside vent of water heater is turned on and it is full of water. Let us know what you find.
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7