One problem that may develop with the furnace is that it sometimes blows cold air out of the registers. Here are just a few of the reasons that you have cold air blowing from the furnace.

  1. Inspect the fuel source

    Make sure there is no disruption in the fuel supply. If you have an electric furnace, make sure the switch is turned on. In the case of a gas heater, the gas valve should be open. Oil tanks must have the appropriate amount of oil to effectively heat the house.

    The furnace will not be able to generate warm air if the supply line is cut off resulting in cold air blowing through the ducts.

  2. Examine the air filter

    A clogged air filter will result in inefficient operation of the furnace. Dirt and dust that accumulates on the filter will prevent air to reach the furnace. As a result, the furnace will take longer to generate heat.

    If the filter is not cleaned, the furnace will eventually stop blowing warm air, and cold air will flow from the outside and circulate inside the rooms.

  3. Inspect the thermostat

    In certain situations, a thermostat can also make the furnace blow cold air. This will usually be the case when the temperature battery is dead. Also, if the thermostat is set at a lower temperature than the house temperature, it can result in cold air blowing from the furnace.

    Sometimes setting the thermostat to ON instead of AUTO results in cold air blowing from the system. This is especially the case if you notice that the blower is constantly running but the furnace tends to blow cold air occasionally.

  4. Cracks inside the ductwork

    A crack inside the ductwork can allow cold air to seep inside the system. The furnace may be functioning properly but the warm air might be blown out of the registers. A professional furnace technician can carefully inspect the ductwork to find out if the cold air is blowing inside through a crack.

  5. Pilot light problem

    A faulty pilot light can also be the cause of cool air blowing from the air registers. The pilot light is a small flame in gas furnaces that must burn continuously for the furnace to generate warm air. Keep in mind that the pilot light should only be lit by a professional as lighting it yourself pose a fire hazard.

Cold air blowing from the furnace? Call Allbritten for emergency service!

If you reside in the area of Fresno in California, you can contact Albritten technicians to solve all kinds of furnace repair issues.

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Aaron Marquez
Aaron Marquez

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