Why Your Furnace Blows Cold Air

Posted: 2020-11-05

During cold months, nothing satisfies more than a warm, toasty home. But what if you turn your heating system on and realize it’s releasing cold air instead of warm? This can be really frustrating, especially if it happens in the middle of the night.

The good thing is that there are ways to find out whether a furnace is doing what it’s supposed to do or not. That’s our main goal in writing this article.

Four Seasons Air Specialists is your friendly heating company in White Bear Lake MN. We have been in the HVAC industry for over forty years, and we know furnaces from the inside out. Allow us to give you some idea as to why a furnace is blowing cold air.

An Overheating Furnace

Regardless of what system you are using, overheating is never a good sign. When a furnace overheats, it turns itself on and off unnecessarily. This problem is called “short cycling,” which is the leading cause of high energy consumption and furnace failure. 

One of the possible causes of overheating is a dirty filter, causing your furnace to limit the airflow within the heat exchanger. This lack of proper airflow causes the furnace to use more fuel than usual. Checking and replacing the furnace filter as often as possible can help prevent this problem. It’s one of the easiest things you can do to keep your furnace running effortlessly. Avoid neglecting this problem as repeated overheating can damage the heat exchanger, which not only is an expensive part to replace but can also cause a carbon monoxide leak in your home.

Also, closed registers can cause your furnace to overheat by increasing the pressure in your air ducts. This added pressure slows down your furnace blowers and compromises the airflow within the system.

Moreover, a clogged evaporator coil, a dirty blower wheel, or a broken gas valve can also result in the overheating of your furnace.

Ensure your furnace does not overheat, schedule a routine inspection and maintenance at least once a year. A qualified technician understands your furnace and can detect issues before they escalate and become more severe problems.

Ductwork Issues

Your furnace produces heated air, which is then carried throughout your home via the duct network. If there is any leak, a crack, or any form of damage anywhere within the ductwork, your furnace will blow cold air.

These tiny openings will collect cold air that mixes with heated air, disabling your furnace from reaching your desired temperatures. Severe damages to the ducts can even result in losing heated air altogether. When this happens, it’s inevitable to have cold nights and excessively high energy bills.

For this reason, you should regularly maintain your air ducts. The task of taking care of ducts can be quite challenging for an untrained individual. It’s best to have a qualified technician come and inspect your ducts.

Thermostat Problems

Another main reason for a furnace to blow cold air has to do with the thermostat. This device controls your heating system, determining when and how much heat will be created by the furnace. If your thermostat is set to ON instead of AUTO, it is still possible for it to cause your furnace to blow cold air.

If your thermostat has old or damaged wiring, a buildup of dust, extreme temperature changes, and similar issues, it can cause your furnace to produce cold air instead of warm.

Uncomplicated troubleshooting steps like changing the battery usually fix the problem. Weak or dead batteries are the leading causes of thermostat malfunction. Also, unsecured electrical connections, faulty or old wiring can result in thermostat issues. If the thermostat problem seems too complicated for you, consider calling an HVAC professional or replacing it with a brand-new one instead.

Trust No Less than the Heating Pros

A malfunctioning furnace can cause stress and put your health at risk at the same time. To restore the heat in your home and ensure your heating system stays in tip-top shape, call Four Seasons Air Specialists. We exist to provide solutions to your home comfort problems. Our friendly and seasoned technicians are easy to talk to and deliver outstanding workmanship. We are your reliable Dellwood furnace repair company.