I have a suburban SF-30F furnace and lately I set the temp on the thermostat to 75 or 80 and after maybe 10 minutes it turns off. I have hot air coming through the ducts so that's not the issue it just stops. I can reset it again and the same thing happens. It stops after about 19 minutes. Does anyone have an idea what it is that's wrong? I've heard the limit switch is bad. Is that the case?
If the limit switch were bad, the blower would keep running- does it do that? For the blower to stop, the fault has to be either power, thermostat, blower relay (either separate or on fan control board), or blower motor.