Furnace Thermostat Not Working_Howard Air

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You try to set the heat in your home, and the furnace doesn’t kick on. Panic is usually the first emotion. The thought that your furnace may need to be repaired or replaced is a daunting one. HVAC repair does not come inexpensively. If your furnace seems to check out okay, isn’t that old, and has had regular maintenance checks, the problem may be as close as your thermostat.

Your Thermostat

Your Thermostat_Howard Air

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Your thermostat is the “brain” that tells your furnace what you want it to do. When your furnace thermostat is not working, your furnace does not know if it needs to work to heat up your home or if it can rest. Most common issues with thermostats can easily be fixed if you know what to check for. Here are the things you need to check and what you can do if this is where the problem originates.

Check the Power

Check the Power_Howard Air

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Thermostats get their power from one or more of three different sources, depending on the type of thermostat you have.

  • Check to see if the battery is old and no longer working. If so, a simple replacement will have you back up and running.
  • Check for a blown fuse that needs replacing. Replacing the fuse is quick and easy.
  • Check your circuit breaker. Many newer thermostats are hooked to the electrical system. If the circuit breaker is tripped, you need to only flip the switch back to the on position.


Dust_Howard Air

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Thermostats are susceptible to dust like any other electronic device. Carefully remove the outer cover of your thermostat and use either a small paintbrush or canned air. If using the air, gently blow off any dust. If using the paint brush, try to use as light of pressure as you can to still remove the dust.

In either case, you want to make sure you get all areas inside the thermostat. To do this, turn the thermostat to its lowest position and clean the right side. Then turn it all the way up and clean the left. Now you can put it wherever you feel comfortable. If dust was the problem, the furnace should now be working fine.

Loose Wires

Loose Wires_Howard Air

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Any time wires are involved there is a chance of one coming free, or completely disconnecting. As you change the setting on your thermostat over time, the wires can become loose or break. This will most likely need to be handled by an HVAC person as wiring that is not handled correctly can cause a fire hazard. If there doesn’t appear to be any broken wires, but moving a wire or two causes your furnace to kick in, set up an appointment to have the thermostat serviced or replaced.

Wrong Location

Wrong Location_Howard Air

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This is most likely to happen if you have recently installed a thermostat or done some renovation that changes the structure of things within your home. Make sure the thermostat is not near any natural light source, like a window.

Warm sunshine can trick the thermostat into thinking it is warmer in the house than it is. A cold breeze from a window or other crack can make the opposite impression. The thermostat should ideally be placed on an interior wall somewhere near the center of your home. In that way, it can get the most accurate gauge of the inside temperature. Moving the thermostat will require an HVAC contractor.


Age_Howard Air

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Nothing is made to last forever. Thermostats get old and wear out like any other object. If yours is old, or if you have no idea how old it is, consider having a specialist come to check it out. Replacing an old thermostat with a newer model may not only solve your furnace issues but could help you save both energy and money. More modern thermostats are more energy efficient. They also work with less effort than an older model that is starting to get old. You may even opt for a programmable thermostat that can save you an even more considerable amount of money.

Final Thoughts

Can a bad thermostat cause your furnace not to work? As you can see, the answer is a resounding: Yes, it can. The best way to avoid surprises with both your furnace and your furnace thermostat is to have regular maintenance done on your home’s heating system. At Howard Air, we would rather spend time checking out your system before it needs repair because we know you’ll be much happier than if you need to call us for a heating repair. Contact us now and set up an appointment to have your HVAC system thoroughly checked and optimized. We won’t leave you out in the cold.