Ok so I have lived in Alaska for 2 years and used my Block Heater there with no problems, I move back to North Carloina and use it 1 year and now that it has dropped off really cold outside and I try to use it, it is not heating up? I have looked in the owners manual for a fuse location and tried different extension cords as well as plugging it inot other locatiions and nothing changes. Any suggestions as to what I should check next before I fork out any money to change out the heater?