Function

• The RV hot water heater comes equipped with a pressure relief valve that opens if the water temperature reaches 210 degrees F. It is also supposed to open in the case of a build up of pressure. When the water supply pressure hits 50 lbs. per square inch (PSI), the unit's relief valve will pop open and water will come out the valve. The valve will then close when the pressure drops back down to 50 PSI. It is normal for a RV hot water heater to drip in this manner. It is not defective or a malfunction.
  
  

Types

• Most RVs come equipped with a hot water heater that has a capacity of 6 gallons. Some larger vehicles may have larger heaters. They usually hold about 10 gallons of water. Most RV hot water heaters rely primarily on propane gas. It is important to note, however, that some run entirely on gas whereas others use a combination of gas and and 120 Volt AC.
  
  

Features

• To operate your RV hot water heater, you may need to light a gas pilot light. Other hot water heaters have an automatic, direct spark ignition (DSI) system. These heaters are operated by flipping an electric switch inside the vehicle. Another feature allows you to drain the hot water tank and winterize the appliance much easier. It is called a by-pass valve kit and it saves you time and anti-freeze. It is installed near the water heater's cold water inlet. The feature promotes the blockage of water to flow into the appliance.
  
  

Considerations

• Before first operating your RV hot water heater, make sure that there is water in the tank. Check to make sure that the bypass valve, if there is one, is open because this will allow water to flow. Then, connect the vehicle to a water source or turn the on-board water pump on. Next, open a hot water faucet and wait until the water is flowing strongly, free of air pockets. Once water is coming out of the tap, you can be rest assured that the hot water heating tank is full and is safe to operate.
  
  

Storage

• If you are not using your RV for a while or storing it for the winter, the hot water heater should be drained. This will help avoid damage in case it freezes. Sometimes, mineral content in water supplies can build up and deteriorate the tank, so this will help avoid that, too. To drain the water heater, turn off the power at the main breaker or by flipping the switch inside the RV. Turn off the water pump and the gas supply and open all faucets and fixtures through the RV, hot and cold. If there is a bypass valve, put it in bypass position. Open the access door to the water heat and remove the anode rod. This will allow water to drain from the tank.