It’s the middle of winter, and you go to turn on your furnace only to find that it’s blowing cold air. What gives? Before you start Googling “furnace repair near me,” let’s figure out what’s happening.
Why Is My Furnace Blowing Cold Air?
Most people immediately assume something is wrong with their furnace and panic. However, there’s no need to worry just yet. In most cases, a furnace blowing cold air is a regular occurrence that can be easily fixed.
The Temperature in Your Home is Above the Set Point on Your Thermostat
If the temperature in your home is already above the set point on your thermostat, your furnace won’t turn on at all. However, if your home temperature is slightly above the set point, your furnace may turn on but blow cold air. This is because furnaces are designed to maintain a consistent temperature in your home, not to raise the temperature quickly.
The Pilot Light is Out
This is the most common reason for a furnace to stop working. If the pilot light goes out, the furnace will not be able to ignite the burner and will not produce any heat. So first, check to see if the pilot light is on and if it is not, relight it according to the manufacturer’s instructions.
In some cases, you may be able to see that the pilot light is out simply by looking at the furnace. However, in other cases, you may need to remove a panel from the furnace to see the pilot light. Of course, if you’re uncomfortable doing this yourself, you can always call a professional for help.
The furnace filter is dirty.
A dirty filter can restrict airflow and cause the furnace to overheat. As a result, the switch that turns off the furnace when it gets too hot will trip, causing the furnace to stop working. Replace the filter with a new one.
The Furnace Is In DIY Mode
Some furnaces have a DIY or Do It Yourself mode that allows homeowners to perform simple maintenance tasks like changing the air filter without having to call a professional. While this mode can be convenient, it’s also easy to forget that the furnace is in DIY mode when it’s time to turn it on for the first time in the season. As a result, the furnace may blow cold air because it thinks you’re still working on it!
The furnace is turned off.
Believe it or not, this happens more often than you might think! People forget to turn their furnaces on all the time. So, before troubleshooting, double-check that your furnace is turned on.
The thermostat is set to “off.”
This is another common mistake people make with their furnaces. They think they’ve turned the furnace off when they just set the thermostat to “off.” So, if you find that your furnace is blowing cold air, check the thermostat to see if it’s set to “off” or if it’s set to a temperature below the current room temperature. Then, suppose it’s set to “off,” turn it back on and adjust the temperature accordingly.
The blower motor is turned off.
In some furnaces, the blower motor can be turned off independently from the rest of the furnace. So, if your furnace is blowing cold air, check to see if the blower motor is turned off. If it is, turn it back on, and your furnace should start blowing warm air again.
The limit switch is tripped.
The limit switch is a safety feature that prevents the furnace from overheating. If the limit switch trips, it will cause the furnace to shut down and stop blowing warm air. To reset the limit switch, follow your owner’s manual instructions or call a professional for help.
The blower motor is not working.
The blower motor circulates air through the ductwork and into your home. If the blower motor is not working, no heat will spread, and you will be left cold. Check to see if the motor is running and if it is not, replace it with a new one.
There is a problem with the gas line.
If there is a problem with the gas line, then there will be no gas flowing to the furnace, and it will not be able to produce any heat. Call a qualified technician to inspect the gas line and make any necessary repairs.
If your furnace starts blowing cold air, don’t panic! In most cases, it’s a simple problem that you can easily fix without calling a professional. However, before you call a technician, check things like the pilot light, thermostat setting, and blower motor—one of these might be why your furnace is blowing cold air instead of warm air!