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Why is My Furnace Blowing Cold Air?

Baby, it’s cold outside and the situation indoors isn’t much better. It isn’t normal to feel cold air from a furnace. When you do, the cause may be a simple fix or an issue that requires expert help. Before you call an HVAC expert and ask, “Why is the air from my furnace cold?” try some DIY solutions first.

Why is My Furnace Blowing Cold Air: Troubleshooting Tips

Overheating and Air Filters

A clogged, dirty air filter may hinder heating equipment’s ability to warm your house effectively and efficiently. If the equipment has to work overtime to make your home feel comfortable, it might overheat and shut down the burner, making it seem as if cold air is blowing into your home.

If more than a month has passed since you lasted changed the filter, change it now. Restart the furnace and continue to replace the filter on a monthly basis.

Thermostat Mode

Thermostats have two modes: heat and cool. During the cooler months of the year, make sure the thermostat is set to “Heat” mode to prompt it to warm your home. When the weather warms up, switch it to “Cool” mode.

Thermostat Batteries

When the batteries in a thermostat start to die, your heating equipment might not work appropriately. If your thermostat works on batteries alone, instead of being connected to your home’s central power, try replacing them.

Thermostat Temperature Setting

If you still feel cold air coming from the furnace after verifying the thermostat is in “Heat” mode, check the temperature. The set temperature should be warmer than the room’s temperature. Try raising the temperature 5°F to see if it makes a difference.

Thermostat Fan and Limit Switch Settings

If the fan continuously blows, it may send cold air into your home even when your heating equipment finishes cycling. If the fan is set to “On,” switch it to “Auto.”

If the thermostat fan setting is on “Auto” and the fan continues to blow, check the furnace’s limit switch. You’ll find it under the hood. Like the thermostat, the switch should be set to “Auto” instead of “On” or “Manual Override.” If the switch’s button is depressed, pull it out to place it on “Auto” mode.

Air Duct Leaks

It’s normal for ductwork to develop leaks with time. When ductwork has a leak, cold air will enter a duct and blow into your home. At the same time, warm air will escape through the leak and enter the unoccupied space. Your home might also seem more humid and dustier than normal.Check leaky air ducts

If you feel cold air coming from your furnace and the previous troubleshooting tips did not help, there might be a leak in your ductwork. Securing mastic or foil tape designed for ductwork over the leak—if you’re able to locate it safely—might help. Otherwise, call a specialist to inspect your heating equipment and ductwork.

Electronic Control Panel

Newer furnaces have electronic control panels that might act up. Resetting the system by turning the furnace off at the power switch and then back on after a few minutes might help resolve the glitch.

A multitude of issues—from faulty ignitions to empty oil tanks—can leave you wondering, “Why is my furnace blowing cold air?” If simple troubleshooting doesn’t resolve your heating problems, it’s time to call a specialist. HVAC professionals are trained to find and fix furnace problems quickly, so you don’t have to spend a minute longer in the cold than necessary. If your heating equipment isn’t performing as effectively as it should, schedule a free consultation with AAA Heating and Cooling today.