A too hot furnace is more than just a matter of discomfort; it can also be dangerous. While a furnace that doesn’t produce sufficient heat is an annoyance, a furnace that overheats is a warning sign that should not be ignored.
Gas furnaces are designed to safely operate within a very specific maximum heat rating, which is why most home thermostats do not allow a setting above 90 degrees. A too hot furnace will produce warning signs that need to be diagnosed and resolved by a certified HVAC technician. Here are some red flags that may indicate a too hot furnace:
- Odors. Overheating furnace components typically emit an acrid odor of hot metal and/or burning dust. Electrical wiring inside the furnace may also overheat and produce a pungent odor that is associated with something burning.
- Short cycling. A high-temperature limit switch in the furnace detects excessively high temperatures inside the unit, automatically shutting off gas supply to the burner. When the furnace cools down, it may restart normally but soon rapidly shut down again.
- Strange noises. Excessively high internal temperatures may cause furnace materials to expand or distort, making knocking or clanging sounds which are transmitted through the household ductwork.
Why a Furnace Overheats
- Inadequate air circulation. If airflow through the furnace heat exchanger is insufficient, the unit may overheat. The most common cause is a clogged system air filter. Alternatively, the furnace vent pipe, which is typically routed through the roof of the house, may be obstructed.
- Blower-fan failure. A defective blower motor or associated electrical wiring may also cause internal components in the furnace to overheat due to lack of sufficient circulating air.
- Dirty internal components. If the furnace heat exchanger accumulates excessive dust or grime, it may not transfer burner heat into the system airflow efficiently. This can cause the heat exchanger or other associated burner components to overheat.
Serving Terre Haute homes since 1922, Paitson Bros. professionals are ready to provide experienced service and repair for a too hot furnace or any other heating malfunction this winter.
Jeff Paitson is a third generation business owner who continues to run the business with the same values that have been passed down from previous generations since 1922.
Jeff’s belief is that the business belongs to Jesus Christ; therefore 10 percent of the company’s profits go toward the Maryland Community Church.
Jeff is a Terre Haute Chamber of Commerce member and in his spare time, he enjoys 
Ethan Rayburn is a lifelong resident of Terre Haute and a 2005 graduate of Purdue University.
An Eagle Scout, Ethan spent four years as a non-profit executive with the Boy Scouts of America before joining Paitson Bros. as a comfort advisor and later General Manager. In that role, Ethan has brought a renewed enthusiasm for customer care, integrity, value, and service to Paitson Bros. Heating & Air Conditioning.
Ethan enjoys singing and was a member of the Purdue Varsity Glee Club. He also enjoys playing and coaching soccer, spending time with his family and two young boys, and volunteering his time and resources with his church, Terre Haute First Baptist Church, which he has attended from a very young age.
Paitson Bros
1 (812) 232-2347
Serving the Wabash Valley, IN Area Since 1922