Is Your Heating System Blowing Cold Air? Keep Up with Furnace Maintenance

The Weiss-Johnson Blog

This is the time of year we start getting a lot of questions about furnaces. Chief among them: why is my furnace blowing cold air? It’s a frustrating problem – it’s cold outside and you turn on your furnace expecting to warm up. Instead, you feel like you’ve opened the door to a freezer. There are three common reasons that your furnace is malfunctioning, and the solutions range from a simple flip of a switch to needing to call a professional HVAC specialist to do some furnace maintenance or repair.


Before you do anything else, check to make sure your thermostat is set correctly. Having the thermostat set to “AUTO” tells your furnace to only blow air throughout the home when the thermostat is calling for heat. Conversely, when the thermostat is set to “ON,” it will continuously push air throughout your home, regardless if it’s heated or not.

Air Filters

Air filters should be checked monthly and replaced as needed as part of your furnace maintenance. When they become dirty and clogged, warmed air cannot move out and away from your unit. This forces the air to move back over your furnace, and in turn forces your furnace to overheat and trip the limit switch (a safety feature that turns off the furnace burners). This results in cold air blowing through vents instead of warm air. Continually overheating the furnace can cause damage to the heat exchanger, which is a costly furnace repair.

Pilot Light

Sometimes, a pilot light goes out accidently and needs to be relit. If it won’t ignite, be sure to check that the gas line coming into the furnace is open and the pilot is clean of any debris. A pilot light that keeps going out indicates a problem with the thermocouple (a sensor used to measure temperature) that will require a service technician to perform heating repair.

Weiss-Johnson is Edmonton and the Surrounding Area’s premier furnace repair provider. For expert service and advice, you can count on our trained technicians to do the job right. You don’t have to live with cold air blowing throughout your home; we can provide emergency furnace maintenance and repair whenever you need it, 24/7.


The Weiss-Johnson Blog Team

We are the Weiss-Johnson Blog Team! All blog posts are written by a collective of WJ employees. Each one of our articles is designed to inform our customers of all the happenings in the world of home comfort! Thanks for reading!

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