Gas Forced Hot Air Heater Not Working

When your furnace fails you, whether it’s the first time you turn it on for the season or the middle of a snowstorm, the thought of an expensive service call is daunting. If natural gas or propane fires up your gas forced hot air heater, there are steps to take to decipher the problem on your own before calling in a professional.

Instructions

- 1
  Check the setting on the thermostat. Make sure it is set on heat and then check the temperature. If it is set lower than the temperature inside your home, the gas forced hot air heater will not turn on. Check the batteries on your thermostat if applicable. Digital thermostats operate by battery and are unable to operate when the batteries lose their charge.
- 2
  Find the circuit breaker that controls the furnace in your home’s control box. Verify there are no loose wires on the unit. Reset the breaker or change it if blown.
- 3
  Relight the pilot light if not illuminated or check that the igniter sparks. Confirm the flame on the pilot light touches the thermocouple. The thermocouple is a sensor that measures temperature.
- 4
  Look at the gas control valve carefully to ensure it is in the open position. Open the valve if it is closed. The instructions for opening your furnace's gas valve may vary based on the model.

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