My Suburban water heater doesn’t work on shore power, or any other 120 power source. I made sure the switch was on at the water heater. I also verified I had power at the outlet that the water heater is plugged into and that it was actually plugged in. The only obvious thing I see is that there is no switch for the water heater to run off of 120 on my control panel. The only switch is for gas operation. Do I need the second switch? I looked on the Forest River website, but it’s of no help, and the dealer is backed up for months. Can you help?? —Kevin, 2021 East to West Della Terra 271BH
Your Suburban water heater has a switch on the face of the water heater in the lower left. This switch provides 120-volt power to the heating element. This photo shows the switch with tape over it to ensure it is in the off position when sent to the dealership.
You should also have a switch inside the rig that turns the water heater on and off in either mode. If the switch on the actual heater is off, turning the inside switch on will send 12-volt power to the module board and it will start the lighting procedure for the propane mode of operation. If the switch on the unit is on, turning the inside switch on sends 12-volt power to the module board, as well. However, it will then allow 120-volt power to go to the heating element, which is located just to the left of the drain plug behind the black plastic cover.
120-volt power is supplied to the water heater from the distribution center with a 15-amp circuit breaker. Since you verified there is 120-volt power to the outlet, the circuit breaker is on. Next, check to verify you have 120-volt power to the switch on the water heater. If yes, check for 120-volt power at the thermostat. There is a high limit switch on the black rubber cover just below the relief valve. The right side button is for 12 volt and the left is 120 volt. These can be reset by pushing them in and feeling a click. If you have power to the switch, check for 120-volt power at the heating element. You can check the heating element with the power off and check for continuity and it should have an Ohm reading of 10 Ohms of resistance.
Remove the element and check for calcium buildup, an expanded element, and cracks. The most common issue with heating elements is starting the water heater on the electric mode without water in the tank, which will ruin the heating element. This is common in the spring when bringing the unit out from storage and not realizing the switch on the unit is in the on position.
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