Most RVs have a propane-fueled water heater. There are also some that are dual propane-electric. These water heaters are either 6 or 10 gallons, depending on the size of the RV. Some will have an automatic ignition, while other must be lit manually. The heater is accessible from the outside through its ventilation grill.

Six to 10 gallons of water should be sufficient for at least a couple of showers if water is used judiciously. Most RV showers have a dial that reduces the flow of water. To save water, wet your body, turn off the flow of water and soap up, and then turn the water flow back to normal and rinse off. Leave your fifteen-minute showers for home with its 40-gallon water heater.