subject: RV Expert Bruce Bernhart on the Hot Water Heater [print this page] Bruce Bernhart shares this report from ccis.com on the do's and dont's of operating your RV hot water heater
Unlike the water heater in your house which requires little or no user intervention, operating the typical RV water heater requires you to pay attention to a couple of things.
First and most important, before lighting the water heater gas pilot or turning on any electric heating function, make SURE that the water heater tank is filled with water! Check to be sure that the water heater inlet and outlet lines are not bypassed with a winterization bypass kit and that water flows from the hot faucet in the sink or shower.
Once you're sure, go ahead and turn on the heater. Some heaters utilize an electric heating element in addition to the standard gas burner. Some heaters require a pilot and some are Direct Spark ignition. Check the manual that came with your RV or the data plate on the water heater itself for proper lighting and operating instructions.
Most RV water heaters allow some adjustment of the water temperature. Gas models will have a temperature adjustment right on the gas valve. Gas/Electric units will also have a separate thermostat for the electric side, but locations and accessibility will vary. Best to consult the manual unless you like to play detective... Be careful not to set the temperature too high... it's easy to get severely scalded by water heated beyond 140 degrees.
It is not uncommon to see some weepage from the pressure relief valve on the outside of the water heater when initially heating a tank of cold water. This is caused by the expansion of the heated water and indicates very high pressure within the water system. You can open a faucet briefly to relieve the pressure, but the best permanent fix for this problem (in my opinion) is to add a small expansion tank to your water system. The expansion tank will absorb the pressure fluctuations and smooth the water flow in your rig.
If you have a water heater that utilizes a pilot light, you may be amazed to find that the pilot will heat your water nicely all by itself. Just light the pilot and leave the gas valve in the 'pilot' position when you park.
