RV How-To Guide | A/C, Furnace, and Thermostat Operation

You must always fill the hot water tank before you turn the gas or electric heat on. Most trailers fill this tank automatically when you hook up to a city water connection. Hot water tank controls are usually found in the bathroom next to the gray and black water tank indicators. Consult your trailer manual first before operation.
- To make sure the hot water heater is filled, turn on your taps to make sure the water has ran through the hot water heater to reach the lines. Then turn on your hot water heater to begin pumping.
- If you are using your freshwater connection, then be sure to turn the hot water heater pump on before using any hot water and before turning on the hot water heater. The hot water heater and hot water pump switches are usually found in the bathroom next to the gray and black water tank indicators.
Most trailers have to be plugged into at least a 30 amp outlet for them to operate and most AC units and water heaters will not work on a battery.
Quick Cool Feature - Sometimes there is a vent on the AC unit that can be opened up to cool the trailer quickly.
A common reason AC units are not working effectively is forgetting to close all doors and windows, this will prevent the AC from working effectively.
Many AC units have an auto mode and a manual mode to control the fans and temperature. Auto mode will bring your fan to the tempurature you set it to whereas manual mode will essentially turn your AC on at the desired fan speed until you manually turn it off. Manual mode will keep cooling or heating until you turn it off so it could get too cold or hot. For that reason, it is usually better to leave it in auto mode.
Air conditioners are more designed to pull heat from the trailer and cooling is a byproduct. So when the trailer has been hot all day and you turn on your AC at the end of the day, it has to pull all the heat out of the trailer, including the heat in the carpets, bed, sofas etc. This can take a long time and is very taxing on your AC and energy use. If you are at a full service campsite, it is more efficient and effective to leave your AC running on auto mode in the morning so you can make sure it will be cool when you want to use your trailer at the end of the day.

Go Back to Your RV Handbook