Malfunctioning Thermostat

In the middle of the night I heard the heater fan whirring and I remembered that it was sounding a lot when I went to bed. I went and checked it and the remote thermometer was reading 40.5 degrees under the table. It seemed like the heater may not have been turning off. I yanked the cord and hit the sack. There's a little bit of wiltage this morning but hopefully no casualties.....