Among the many potential heating system problems, furnace cold air is probably the most basic. A furnace that’s not producing any heat whatsoever is failing at its most fundamental function. This can mean something very essential is wrong–or something quite simple. For safety reasons, do-it-yourself attempts to repair gas-fired furnaces are not recommended.
However, knowing the range of possible problems that can lead to furnace cold air may resolve the simple ones and help you describe the more complex issues to a qualified HVAC service tech. Here are three typical scenarios that might apply:
- Thermostat is “On.” While it seems like the correct setting, the “On” setting actually only activates the system blower to circulate cold air. First, the thermostat must be in the “Heat” mode. Then, the correct setting is “Auto” ( instead of “On”) to ignite the burners and produce heat. Make sure the desired temperature setting is at least five degrees below the current room temperature.
- Safety cutoff switch has activated. Certain malfunctions that produce a hazard can cause an automatic cutoff to shut down the furnace burners. The most common is an overheating condition that might result in fire or severe damage to the unit. If airflow entering or leaving the furnace is below the proper volume, for example, internal components of the furnace may overheat and trip the safety cutoff switch. This must be addressed by a qualified HVAC service technician to resolve the cause and reset the safety switch so the furnace can be re-started.
- Duct failures. Disconnected segments or deterioration of ductwork may allow cold air from unconditioned areas of the house like the attic or crawl space into the system. This lowers the overall temperature of furnace airflow and gives the impression that the unit isn’t generating heat. Ductwork issues may unbalance airflow, causing some rooms to feel constantly chilly. A duct inspection including leakage testing and repair is usually required to restore balance.
If the issue is furnace cold air, get professional advice from the heating experts at Paitson Bros. this winter. We’ve served Terre Haute residents since 1922.
Our goal is to help educate our customers in Terre Haute, Indiana about energy and home comfort issues (specific to HVAC systems). For more information about furnace issues and other HVAC topics, download our free Home Comfort Guide or call us at 812-645-6859.
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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