January 23, 2023
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March 9, 2023



When cold winds are howling outside, it can be distressing to find that your furnace is also blowing cold air inside your home. Fortunately, there are some simple things you can do to get your home feeling warm and cozy again. Here are some common situations that cause furnaces to blow cold air.

FAN SETTINGS- Check your fan settings. If it happens to be set to “ON”, it will continually blow air whether the furnace produces heat. By simply changing the setting to “AUTO” this will ensure your gas furnace will only run during the standard heating process. This situation is more common in older thermostats that have a physical fan control switch that can be easily bumped.

PILOT LIGHT/IGNITER- If you notice a strong flow of cold air and an abrupt stop, then your pilot light is likely to blame. Gas furnaces use a small pilot light that burns continuously to ignite a larger burner like your furnace. If the pilot light fails, your furnace will never kick on. Relighting a pilot light is a fairly simple process for most homeowners. Your furnace manual will come with easy troubleshooting steps to relight your pilot light. Newer furnaces do not typically have pilot lights, they feature a solid surface igniter that raises its temperature high enough to engage the natural gas. There is no quick fix for a bad igniter, it will need to be replaced.

DIRTY FILTER- If you find that your furnace or heat pump never seems to warm up the air after completing a full cycle, then you probably have a clogged furnace filter. A grimy air filter can cause longer heating cycles which in turn can lead to overheating issues. Overheating will cause your heater to blow cold air. This can be confusing as most homeowners would think that a clogged filter would prevent air from coming through the vent at all. But even with a clogged filter a furnace will still run, and the blower still does its job and pushes air through the vents. When the filter is clean the blower sucks air through the filter and over the heating elements and then through the vents. But if a dirty filter blocks that air, it will move through any hole, crack in the furnace or vent system causing your system to blow cold air. Air filters should be changed at least every 90 days.

CONDENSATE LINES- High-efficiency gas furnaces have something called a condensate line. This line aids in the removal of moisture. A blockage in this line caused by dirt or debris can deactivate the burners and cause the furnace to blow cold air.

FUEL ISSUES- If your gas furnace is not getting an adequate supply of gas, not only will it not heat, but will also shut down as a safety measure and blow out cold air. Check your gas valve lever to make sure that it is parallel with the gas supply line. Beyond that, troubleshooting gas lines is better left to the professionals. Call- AUBURN HEATING PLUMBING & AC 440-543-1777 or toll free 1-888-543-HEAT (4328)

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