Troubleshooting a furnace that does not turn off begins with examining it for a malfunction or clog. The thermostat, air filter and fuel supply can all be examined in less than an hour. If the error cannot be identified during these steps, contact your manufacturer and have a certified technician examine the furnace.Continue Reading
Turn down the temperature via the thermostat. If the thermostat is too high, the furnace may just be working extremely hard to maintain the temperature level. Lowering the temperature on the thermostat gives the furnace a break and shut it off.
Check to see if the air filter in the furnace needs to be replaced. If the air filter is blocked or clogged, it does not allow the hot air from the furnace to travel throughout the house. This causes the furnace to continue running as it registers that the temperature in the house is not rising.
Establish whether the other appliances that use gas or oil are operating. If they are not, this may mean that the gas or oil fuel supply is not working. If that is the case, the fan or blower continues to run within the furnace as the appliance does not have a fuel supply to burn.