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Diagnosing a Broken Heater: Why is it Blowing Cold Air?

Tips for Dealing with a Broken Heater That’s Blowing Cold Air

Now is the time of year to test your heater to make sure that everything is working properly before the coldest days of winter arrive. It’s also a good time of year to learn a little bit more about your heater to make sure that you’re prepared to handle any issues that arise in the months ahead. One common problem is heaters blowing cold air.

While this sometimes indicates an issue that requires professional service, it often is a simple problem that can be easily resolved. Here are some tips from local HVAC professionals to help you diagnose and repair a heater that is blowing cold air.

Check the Furnace Settings

Oftentimes when your heater is blowing cold air it is because of the settings on the fan. If the fan is set to “On,” the blower will constantly run, even when the furnace unit is not heating. The result is cold air blowing through your vents.

furnace settings

To fix this, switch the setting to “Auto.” This will ensure that the blower is only going when the furnace is heating and will avoid having cold air blowing throughout your home.

Dealing with an Overheated Heater

overheated heaterAnother cause for your heater blowing cold air is if the heater overheats. This can happen for a number of reasons, but often is an indication that the heater is nearing the end of its lifespan and needs to be replaced.

Some common signs that the heating system needs to be replaced include the need for repeated repairs, repeated short cycling, strange noises from the unit and higher utility costs.

An overheated furnace can leave you cold and frustrated during the winter months. If you notice any of these signs or are concerned about your heater’s functionality, it’s a good idea to have your unit inspected before the coldest days of winter arrive.

Replacing Dirty Air Filters

One common cause of heaters blowing cold air is dirty air filters. When air filters get dirty, they restrict airflow. This essentially suffocates your system and can cause it to overheat and blow cold air. The good news is that this is an easy issue to deal with. By regularly changing your air filters, you can keep air flowing through your unit and help your heater to function effectively along with purifying the air in your house.

dirty air filters

Most air filters should be changed at least every 90 days, while those with allergies or pets should change filters every 45 to 60 days. Regardless of when your air filters were last changed, if your unit is blowing cold air, check to ensure that the filters are clean.

Trust Garneski Air Conditioning & Heating

Garneski Air Conditioning & Heating has been providing quality HVAC services to the Sterling and Northern Virginia communities since 1982. Their experience in the field coupled with their commitment to meet each customer’s individual needs makes them the relied upon HVAC company for the region.