I have an electric Coleman forced air furnace in a mobile home (30 years old). Worked fine all that time. Now, all of a sudden, no matter what heat setting, the furnace does not cycle off. The heating element will not shut off. Overheats the home terribly. The only way to shut it down is to cut the power.
Is this the themostat or a limit switch problem?
The thermostat is digital, about 10 years old (not original).
Dave