How to Turn on a Gas Furnace
- 1). Switch your thermostat to "heat" so that your furnace will shift into heat production mode as soon as it is turned on. This will make it obvious as to when the furnace is operational.
- 2). Inspect your gas furnace, looking for a switch to turn it on and off. If you find an on/off switch, toggle it to the other position to see if it turns on. If you do not find a switch or there is no change when the switch is flipped, your furnace is turned off at the breaker. Return the switch to its original position (if you flipped it and the furnace didn't come on.)
- 3). Open your circuit breaker box if you were unable to turn the furnace on by using a switch on the furnace itself. Use the breaker listing to locate the breaker that controls your furnace; it should be in the "off" position. Turn the breaker on and return to the furnace.
- 4). Light your pilot light if your furnace doesn't use an electrical starter. Turn the pilot light's valve to the "off" position to clear any excess gas, then turn it to "pilot" to prepare to light it. Hold down the pilot button (if a red pilot button is present) or press the valve control in to release gas, then use a fireplace match or grill lighter to light it. Turn the valve to the "on" position once it has been lit.
- 5). Adjust your thermostat to the temperature that you want or switch it to a different mode if you don't wish to use your gas furnace to heat your home at the moment.
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