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This unit heating will not cut off. The T stast has been replaced and the fan relay also been replaced. The breaker would have to be turned off before the unit will cut off.
First time he turn breaker off and then back on and it worked good for days then would not cut off. Replaced Tstast and it worked good for about a week then started not working again. So replaced fan relay and worked fine for 2 days, Tonight it stuck on again. Need some help . Thanks Todd

Does the unit respond to the t-stat at all - HEAT/COOL or Fan ON/AUTO?

yes it dose and will work fine for a day or so. Even if the stast tells it to cut off it wll not. heater and blower still run until all power to unit is killed. looks like the sequenceris sticking on and that is also holding the fan on also. Have two on order will try that. Thanks Todd

I concur. Sequencer(s) sounds like the culprit.