An RV has two water systems; you can hook up a hose from the outside, and run the sinks, shower, and toilet from that. The second water system is internal, involving a freshwater tank and a pump. This allows you to travel, and have running water anywhere.
How the RV Water Pump Works
The RV water pump operates on DC power from the RV’s batteries. There is a switch on the RV control panel to turn the pump on and off. This pump draws water from the freshwater tank and pumps it to the sinks, shower, and toilet. The placement of the pump varies from RV to RV, but it will be close to the freshwater tank.
When you are on the road or camped without hookups, the pump allows you to have running water. Just flip the switch and the pump will start. Water pumps are typically noisy, so you should hear it when it comes on.
However, if you are at an RV park and hooked up to the park’s water with your hose, you should turn the pump off. If the pump is still running while you are hooked up to “city water”, you might drain all of the water out of the freshwater tank and not realize it. While RV water pumps can run dry, it still might damage the pump.
How the RV Water Heater Works
RVs come equipped with a water heater; these typically run on propane gas and contain around 6 gallons. Just like the water pump, the water heater has a switch on the control panel, and you may hear it when it comes on.
The water heater is most often placed in a compartment outside of the kitchen; this is because the propane lines are here for the stove and refrigerator. There is a door with vents covering it.
An RV water heater is much smaller than a home water heater, so your showers will be short. People who live in RVs typically turn the water off when they soap up, so they won’t run out of hot water before they’re done. However, RV hot water is very hot, so you should have plenty of water for a short shower. Likewise, a new batch of hot water doesn’t take very long, typically half an hour.
One important thing to note, you should turn off the water heater when you are driving; the wind from driving can blow the pilot light out, and the automatic starter will keep trying to relight it. That could damage the starter. Also, the water heater needs to be turned off when you fill-up the RV with gas; it’s illegal and dangerous to have an open flame at a gas station, and the water heater pilot light is an open flame.