I have an electric furnace that is approx. 15 years old. It will work fine, until about 2:00am, then it will not kick off. I have checked the thermostat, & it is kicking back like it is supposed to, but the furnace continues to run. I had this problem, very sporadic last year. Now it is happening daily. I flip the breaker each day before going to work. When I get home & turn it back on, it may/may not work properly. Any advise appreciated.