it was a 110v unit..so you had to plug it in somewhere..check the circuit breaker you have it plugged into...the heat draw on that thing could have tripped it..mine does work but has not come on in two years...when we camped going west to Asheville it did drop to the high twenties one night but we have heated hose...I had sensor in that compartment and it stated 45 degrees so it did not come on...but the furnace ducting I did do a leg from bathroom and fished a duct to tanks as well..the water tank is in a separate compartment is somewhat insulated...also the pipes from the tank run thru the cargo bay...I have extra small space heaters I could have plugged in but had no need...I have learned that despite all the legal mumbo jumbo..that the coach was built well insulated.