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Why Is My Furnace Blowing Cold Air? This Is What You Should Know

By February 5, 2020August 25th, 2020Blog
furnace blowing cold air

There’s only one thing worse than a furnace not working, it’s a furnace blowing cold air. Don’t freeze on days and nights you should be warm and cozy.

There could be a few reasons why your furnace is chilling the room. This guide will tell you what you need to know if that happens.

Warming Up

When you first turn on the furnace, cold air might shoot out of the vents for the first few minutes. This is normal.

The furnace has to push out the cold air currently settled before the warm air reaches you. The concept is the same as using hot water. There is always a small timeframe of cold water before it turns hot.

You might need to call a technician if it doesn’t warm after a few minutes.

Pilot Light

Older furnaces might blow cold air if the pilot light has gone out. Most pilot lights are fairly simple to reignite. Check on the side of your furnace for instructions.

If you’re uncomfortable doing it yourself, call a friend or family member to assist you.

A pilot light should remain lit and start blowing warm air after it warms up. If the light goes out or the air is still cold after reignition, then you might have a problem with the thermocouple.

The thermocouple is the metal rod that helps regulate safety and heat. An HVAC technician can help you repair this piece.


Sometimes the simplest answers solve the toughest questions. Check the thermostat to see what settings it’s currently using.

A thermostat in the “on” position will blow air even if a furnace isn’t heating anything. Change your settings to “auto” and set a temperature for the heat to work.

You will save money on electricity bills and know exactly when the heat is working.

Dirty Sensors

A dirty flame sensor can cause your furnace to start heating for a few moments and then turn cold immediately.

Pilotless ignition furnaces use flame sensors to activate and monitor the ignition burn.

Depending on how knowledgeable you are, someone can clean the sensor and restore the heat; however, a trusted technician can help you.

Filters of a Furnace Blowing Cold Air

An overheated furnace will cause cold air to emit from vents. Furnaces can overheat from having dirty air filters.

Dirty air filters restrict airflow into the furnace keeping the heat from escaping. Replacing the filter should solve this issue.

If clean filters don’t help, you may have a more serious problem with your furnace. Have a professional come to the house to check for a damaged igniter or faulty circuit board.

Only trained professionals can evaluate the damage of a furnace.

Time to Heat Up

One day or night without heat can feel like an eternity. Don’t let a furnace blowing cold air make you suffer.

This guide can help you evaluate or fix the problem. Let the professionals make your life easier, and contact us today so we can get the heat back.