A faulty thermostat can cause your heating unit to run and not turn off. The unit may have a broken heating sensor, the wiring may have gone bad, or the switch itself may have broken. The older the thermostat is, the more at risk you are for this happening. Fortunately, a broken thermostat is an extremely easy fix.
Why does my furnace keep running after I turn it off?
Step 1: Locate your fan limit switch
But if the furnace fan runs continuously, regardless of whether the furnace is heating or not, your furnace fan limit switch is either: Set incorrectly to Manual or. Faulty and needs to be repaired/replaced.
What does it mean when your furnace keeps running?
When a furnace runs constantly, it probably means that something is dirty or clogged. The filter is the first thing you want to check, especially if you do not replace your filter as often as recommended (once a month during the heating season).
