Furnaces

Is It Possible for a Furnace to Get Too Hot in Winter?

While a furnace that warms your home efficiently and safely is a real benefit during cold Oklahoma winters, an overly hot furnace might be malfunctioning and can present a hazard. Today’s gas-fired furnaces have an excellent safety record if the unit is professionally installed and receives annual preventive maintenance. Still, certain issues may arise over time, including overheating. If you ever suspect that you have a hot furnace at an unsafe level, always contact a qualified HVAC contractor immediately. 

Signs of an Overheated, Hot Furnace

  • The smell of something burning coming out of HVAC vents inside the house. While a few minutes of acrid odor is to be expected when the furnace is first started up at the beginning of the heating season, this should dissipate rapidly. Any suspect odor that occurs later is a sign to shut off the furnace and call for professional help.

  • The furnace shuts down quickly. If your furnace automatically turns itself off soon after cycling on—known as “short cycling”— it may be the safety sensor detecting excess heat somewhere in the unit. Alternatively, the sensor itself may be defective. If an automatic safety shutdown occurs, don’t keep restarting the furnace until it’s been inspected by a certified HVAC technician. Also: Many furnaces will not restart after a safety shutdown until a technician resets the sensor.

Causes of Your Furnace Overheating

  • Insufficient system airflow. If the air circulating through the furnace is obstructed, internal furnace components of the furnace, such as the heat exchanger, do not receive sufficient cooling and may overheat. This can permanently damage critical components, as well as pose a fire hazard. Causes of restricted airflow include a clogged system air filter and obstructed supply or return vents.

  • Failing components. A worn-out blower motor often overheats, causing pungent burning odors before it fails completely. Aging electrical wiring inside the furnace may also begin to disintegrate and melt when exposed to heat.

For qualified professional service to diagnose a hot furnace, contact the heating experts at Air Assurance.