Why is My Heater Blowing Cold Air?

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September 18, 2019

Even though the temperatures are still mild, it'll soon be time to think about turning on the heat. Turning on your heat and feeling a blast of cold air can be caused by a variety of issues.

Read on to learn about some of the common causes of why your heater is blowing cold air and how to resolve them:

Dirty Air Filters

One common cause your home heater is blowing cold air is a dirty air filter. Over time, the air filter inside an HVAC unit may become clogged with all sorts of contaminants such as dirt and pet dander. A dirty air filter blocks the air from the system's heat exchanger, which causes it to overheat, shut off and ultimately only blow cold air.

Make sure to swap out your air filters every 30 to 60 days to ensure that your HVAC units works properly. If you have pets, you might need to change it more often. Talk to our licensed HVAC pro to determine what type of air filter is right for your home; you can also discuss air purification options and duct cleaning to ensure your system doesn't become quickly overloaded.

The Fan Might Not Be On

If changing the air filter didn’t fix the problem, you might want to take a quick look at your thermostat. Running the fan might not be the best thing during the summer, but when winter hits, you’ll need to turn it on. Make sure to not keep the fan in the on position for too long. Excessive fan use can significantly increase your utility bills.

The Flame Sensor Needs Cleaned

Most furnaces have a flame sensor inside, which indicates if the heater is making the air warm. A flame sensor is also what detects the presence of a fire. For furnaces, the flame sensor is used to indicate whether or not the gas valve was opened. In most cases, the flame sensor in a furnace is located near the burners. You'll notice that it's merely a bent, metallic rod.

If the air that comes through is warm for a moment, but then goes cold, the flame sensor may need cleaned. It’s not recommended that you try to clean it yourself as you may end up damaging the parts on accident. Enlist the help of our qualified HVAC professional and they’ll handle it for you.

Having a faulty heater is something no homeowner wants to go through, especially during the winter. With cooler temperatures right around the corner, now's the best time to prepare ahead of time by calling an HVAC professional. Contact Master Mechanical at (847) 796-6665 for more information today!

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