Why Would Your Furnace Be Blowing Cold Air?

On a cold day, nothing feels quite as good as walking into a cozy warm home, feeling the warm breeze flowing through the vents. 

But it doesn’t always work that way. Sometimes you turn your furnace on expecting warm air, and the only thing you find is that the furnace is blowing cold air. 

What’s causing it? The good news is there are many ways to solve the problem, with some of the solutions easy to fix on your own. Where do you start?

Faulty pilot light

How old is your furnace? Furnace technology has evolved over the years. While furnaces up to 2010 were built with pilot light ignition systems, there after electronic ignition systems were phased in instead. If your residential furnace still uses a pilot light for ignition, it can have problems or be damaged from normal wear and tear. Try relighting the pilot light to see if that solves the problem. If you have an issue getting the pilot light lit, or keeping it lit, check in with a professional to get to the root of the problem. 

Why Would Your Furnace Be Blowing Cold Air?

Dirty air filter

When was the last time your furnace was serviced? If you schedule a maintenance visit at the start of the winter season, an HVAC technician will check over the entire system to ensure it’s operational, and will change out the air filter to allow proper air flow distribution throughout your home. If you feel cold air blowing from the vents, the air filter may be dirty, impeding the furnace from receiving and sending out proper air flow. 

Damaged ductwork

While most people know the furnace and air conditioner require regular maintenance, they often don’t give the ventilation system much thought. Cracked and damaged ductwork can cause serious issues with your heating and cooling. When the furnace blows cold air out into the ductwork, cracks can allow it to escape where it shouldn’t be … in your attic or behind the walls. Since ductwork isn’t easy to get to and assess, you’ll need to bring in a professional to help find and solve the problem. 

Thermostat problems

Sometimes the furnace blowing in cold air is a thermostat problem. Check your thermostat to ensure it’s set properly. It may have been moved to the wrong setting, causing it to reduce air flow. Be sure the thermostat is set at “auto” rather than “on” to ensure it works as efficiently as possible. 

Clogged condensate lines

Modern equipment comes equipped with condensate lines to remove moisture from the air. Over time, this can become clogged with dust and other particles. If the debris builds up, it could cause a blockage and disable the burners, which in turn leads to cold air coming out of the furnace. An HVAC technician can check the drain pan and unclog and clean the lines. 

Is your furnace blowing cold air? Give us a call today. We’re happy to help return your furnace to good working condition, or help you select a new system that will increase your comfort and your efficiency. 

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