My furnace won’t stop running – what should I do?

Having heat is winter is obviously a good thing during winter here in Connecticut – but sometimes you can have too much of a good thing.

“Too much” can happen if your home heating system is constantly running even after the target thermostat temperature is reached. On the other end of the spectrum, a heating system can run constantly and never reach the target temperature. Either way, you’ll end up with higher heating bills and a less comfortable home.

What should you do when your furnace is constantly running? Start with a little detective work.

When your furnace is constantly running but can’t reach thermostat temperature:

  • Check your thermostat setting – Make sure your thermostat is set to a reasonable temperature (the U.S. Department of Energy recommends 68°F in winter for the best balance of comfort and efficiency). If it’s set to 85°F, your furnace will (understandably) run for a long time to reach that temperature!
  • Check your HVAC air filter – A clogged furnace air filter can reduce airflow throughout the heating system, resulting in warm air not reaching your living space. Check your filter once a month during winter, changing it as needed.
  • Maintain your ductwork – The constant flow of hot and cool air through your ductwork will eventually loosen seals and joints, causing conditioned air to escape. Other minor leaks can also develop within the duct lengths – often in hard-to-see places. If 15 or 20 percent of the heated air produced by your furnace doesn’t reach your living space, the furnace will have to overwork to keep up. In some cases, duct joints can be resealed and voids in ductwork can be covered with tape; in others, professional duct sealing will be needed.
  • Seal air leaks – One reason why your furnace might not be able to reach its target temp is that air leaks could be stealing warm air from your living space. Sealing windows in your house with weatherized plastic, installing doorsweeps on exterior doors and replacing old caulking and weatherstripping will help remove some of these draft sources.

When your furnace keeps running after the temperature has been reached:

  • Check the blower motor – Your forced air heating system includes a furnace, whose burner heats air for your home, and a blower motor, which pushes that air through your ducts and into your living space via vents. What you want to understand is whether the blower is running on its own or in tandem with the furnace; to do this, feel the air coming from the vents – if it’s warm, the furnace and blower are both running. If it’s cold, the blower alone is running. In the latter scenario, check your thermostat to see if it is set to “on” rather than “auto.” If it is, switch back to auto and see if the problem goes away.
  • Troubleshoot your thermostat – If the on/auto solution didn’t fix the problem, check your thermostat for things like disconnected or frayed wires or obvious problems like worn batteries. If you change the batteries doesn’t fix the problem, you’ll probably have to install a new thermostat.

If none of these solutions fixes your problem heating system, contact a heating professional at Jennings Oil & Propane. Our expert heating oil technicians and propane technicians will diagnose the problem and fix it quickly so you can get back to enjoying cozy, comfortable nights in your CT home.

For expert heating oil and propane furnace service repairs in Fairfield County, Litchfield County, and New Haven County, trust the pros at Jennings. Contact us today to learn more!

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