Why Won’t My Furnace Turn On? Troubleshooting Tips

Suffering from furnace issues can leave you heated, and your home in the ice box. Furnaces come with added safety requirements that cannot be ignored. To prevent Carbon Monoxide poisoning, The Centers for Disease Control and Prevention (CDC) recommends that homeowners have their “heating system, water heater, and any other gas, oil, or coal burning appliances serviced by a qualified technician every year.”1 This is not only an important preventative measure to avoid a CO dangers, but can help to avoid many common furnace repair issues.
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My Furnace Won’t Kick On, What Next?

If you do find yourself shivering in the comfort of your home, you can try to win the fight with the furnace by troubleshooting on your own. Be sure to seek out a home furnace repair service provider if you are not trained to perform any of the troubleshooting techniques suggested. Above all, safety first.

What to Check When Furnace Won’t Ignite

Check the Ignition Sensor

If your furnace won’t come on, check the ignition sensor. A dirty sensor could be the reason why your furnace won’t stay on or even why your furnace won’t stop blowing cold air. Only if the furnace’s heat exchanger — the part that actually heats the air — senses an ignition, will it power on the furnace. However, dirt or grime can inhibit the sensor’s abilities. A trusted furnace repair company can carry out a furnace flame sensor replacement and the cleaning it needs to function properly.

Inspect the Furnace Pilot Light

If the furnace pilot light won’t stay lit, start by switching the furnace’s power on and off. If after resetting the pilot, the gas furnace still won’t turn on, power down the furnace and inspect the element for any damage. If all else fails, it is best to call a professional to come and perform gas furnace maintenance as soon as possible.
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Check the Electrical Panel

Circuit breakers also control furnaces. Make sure that the circuit breaker panels and the furnace itself are in the ON position, sometimes a simple solution as to why your furnace won’t kick on. If not in the on position, pop the breakers back into place carefully. Be sure to close the furnace door so the safety switch can activate the furnace.

Thermostat Won’t Kick on Furnace?

Extreme temperatures, wonky wiring, or dust buildup can leave your thermostat not able to properly regulate the furnace’s heat. Here’s what to check first.

Check the Batteries

If the thermostat is not indicating that it’s powered on or won’t kick on the furnace, the batteries might have run out of juice and need a replacement. If your furnace is not heating your house at consistent times, switching to AA lithium batteries instead of alkaline batteries can extend the life and consistency of your system.

Check the Thermostat Position

If your constant chills are making you question why your furnace won’t go above 60, make sure your thermostat is in the heating position. Even changing the physical location of your thermostat away from sunlight and/or drafts will ensure a more accurate reading of the thermostat and heating experience.

Furnace Turns On But Wont Blow Heat

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Check the Furnace Filter

If your furnace powers on but still fails to keep you warm, inspect the furnace’s filter, located in the uptake or furnace itself. Check if it is clogged by dust or other debris. One tip to check clogging is to hold the filter up to the light; if light does not pass through it, you need to replace it. Ensure the furnace is off when replacing a filthy filter, and align it in the direction the furnace is blowing the air.

Learn More: How To Change a Furnace Filter

Furnace Won’t Turn On? Take It Seriously

If not taken care of, a faulty furnace could end up costing you more than just a furnace repair fee. For one, it can hurt your wallet with elevated energy costs over the long-run. Carbon monoxide can also be emitted from your furnace and into your home from a cracked furnace heat exchanger or if the burner is improperly burning fuel.

Because your furnace deals with different gases and ignitions, it is best to always call a professional to handle any further troubleshooting needed to ensure proper furnace repair.

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