The LED power light on the back of all Xtreme Boat Heaters indicates that your heater is powered up and ready for use. 

If you would like to test your heater further by simulating freezing conditions, this can be accomplished using refrigerant spray commonly found in electronics supply stores and also available here.

To simulate freezing conditions,

To simulate freezing conditions, spray the test port labeled on your heater where the thermostat control is located. By spraying this test port for 3 to 4 seconds, you can simulate the low temperature condition that will turn the heater on. The fan should start instantly and heat can typically be felt within a few seconds.

It is a good idea to test your heater periodically, particularly at the start of each cold season to ensure proper operation.

If you can’t find refrigerant spray anywhere, it is possible to test the heater by placing it in an environment below freezing, such as a freezer. Leave the heater in the freezer for at least 1 full hour. It takes time for the metal to cool enough to fool the heater into thinking it’s winter! Plug the heater in immediately after removing it from the freezer, and it should activate.

It is also a good idea to test Xtreme boat heaters after the boat has been serviced by a third party. Depending on the work done, the heater may have been moved, wires may have been disconnected or tapped into for additional equipment, or circuit breakers may have been turned off.