An understanding of basic RV electric power is necessary before you take your first RV vacation.

RV’s have 3 power sources 12 volt dc power, power cord connection and 120V AC power.  All 3 are necessary in certain circumstances.

As you read educational articles “Coach” refers to the camper portion of the RV. “Chassis” refers to the truck portion of the RV.

1. 12 volt dc power:
There is a “coach” battery or series of batteries. This battery supplies
power for the lights, water pump, hot water heater ignition, refrigerator gas valve, starter for the generator, and blower for the furnace. It is important that the batteries are charged as needed.

There are 3 ways for the battery to charge.
a. The RV shore power cord connection will automatically charge the battery when plugged in. If you have a constant connection to electricity, you will have no worries with battery   power
b. The RV engine will automatically charge the battery while running.
c. The gasoline powered generator will automatically charge the battery while running.

If you do not have an electrical connection for the power cord, you will need to monitor the battery level using the monitor panel to be certain the battery charge remains high enough to power any equipment you are using.
It is important that you know the amount of battery power needed to operate items. The furnace blower uses the most battery power of all. If the battery is run down, the furnace will not operate. This is very important during freezing weather, especially if the RV has water in it.

2. 120 Volt AC Power – There are 2 ways you can have ac electricity in an RV, connection to a power
source through the shore power cord, or an onboard gasoline generator. AC electricity supplies power
for battery charging, air conditioning, electrical outlets, the microwave oven, and is one of 2
power sources for the refrigerator. An RV does not automatically have ac electricity available.
One of the 2 power sources must be working.

3. L.P. (liquid propane). L.P. is supplied to the RV from an onboard tank. L.P. supplies power for the stove top,
oven, water heater, refrigerator, and furnace. There must be a supply in the tank and the tank valve must be turned on to work. All RV’s have an L.P. leak detector. Some RV’s require the leak detector to be on for L.P. to flow to the RV. In any case, the leak detector should always be used. There is an L.P. level gauge mounted on the tank and also another in the monitor panel. L.P. tanks have an 80% fill
capacity, so the gauge may not read full.

About the Author: Mike Wilson is a RVDA Certified Master RV Tech. Mike has 25 years experience as an RV Technician and now he’s sharing his knowledge with you. Mike is the president of Wilson RV and
developer for The RV Help Desk