Within the last couple of days, the blower will not shut off. You can hear it shut off momentarily and within a second or two turn on again. I am able to shut the actual heat off using the thermostat, but that does not affect the blower. I can turn the entire unit off using the switch on the side of the unit, but that does not reset the blower when I flip the switch back on. The result of this is that the temperature in the house went up to 70 when I had the thermostat set at 65. Any ideas? Thanks.