Heater Thermostat Not Working Properly?

If you know someone who can change out a thermostat, that is an inexpensive thing to try. I would not do it myself, but I had a friend who did it for me. He was a home handyman. However, in my case, that was not the problem. Since we do not know what kind of heat you have (electric, natural gas, hot water, oil) we can't help you any further. If you have electric heat, call an electrician, and see if that person is familiar with heating systems. If you have some other kind of heat, one usually calls a plumbing shop where you have plumbers who are also trained to work on furnaces of all types. Call one up and discuss your problem. Under no circumstances should you try to fix this yourself, as you have no clue what to do. I always rely on professional help as I also have no clue.