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Why Is My Heater Blowing Cold Air?

If your heater is on and blowing cold air, it is most likely an issue with either your thermostat or your ductwork, but the complexity of heating systems opens up multiple possibilities. Find out what problem your heater might have and contact ABC Home & Commercial Services for heater repair today.

Heater Is Still Warming Up

Whether your heater is electric or gas, heat exchange is not an instant process. It will take a while after turning your heater on to initiate all of the processes involved in creating and moving heated air throughout your home.

Your heater has to first collect and compress the air in your home, then heat it and expel the cold air. Heating systems work by heat exchange so that your HVAC returns the cold air to the outside of your house. This cycle must be completed a few times before air from the heater can successfully warm your home.

Ductwork with poor insulation is more likely to extend the initial heating time of your heater. Make sure that the airways through which your heat travels can maintain the air temperature as they push it throughout your home. It should never take more than a few minutes for the hot air to begin to flow.

Heater Is Not Powerful Enough

The size of your heater affects the volume of warm air it can push out. Larger heaters contain more powerful parts that produce large amounts of heat for big homes. Concern for the environment has raised awareness of the resource costs of large heaters, so most modern heaters are custom-fit according to the size of the living space.

Smaller homes don’t need as much power, so they can save space and energy with a smaller heater. Even in small spaces, however, poor insulation and ductwork can cause a small heater to work inefficiently. If you feel that your heating system is blowing air that’s too cold, check with a professional to ensure that the size of your heater is right for your home.

Thermostat Is Incorrectly Set

Without an instruction manual, it can be tough to know exactly how to set your thermostat. For most thermostats, if you want the heat to blow, you’ll have to set your desired temperature higher than the current temperature in the house. This holds true whether the thermostat is set to auto or on.

Ductwork Is Leaking

The ductwork for your HVAC usually sits in the attic above the insulation where it is exposed to extreme temperature changes. Alternating hot and cold outside temperatures can expand and contract the materials of your ducts, causing breakage along the airways.

Cracks and holes from damaged ductwork can allow warm air to leak into the uninsulated parts of your home, such as the attic, preventing it from reaching your vents.

Dirt and dust from general use can also sometimes block the passageways where air flows, limiting the amount of warm air that blows from your vents. While you may not feel cold air blowing from your heater, air blocked by dirt and dust is likely to be cooler than your desired temperature.

Pilot Light Is Out

Gas furnaces require an ignition source called a pilot light through which natural gas can move and combust to create heat. The pilot light is simply a small, always-on flame maintained by a minimal stream of gas.

If your pilot light goes out, your heater has no ignition source and it will be unable to begin the heating process. You can relight your pilot light using a small ignition source or call a professional for help.

Filter Needs To Be Changed

For oil heaters, filters need to be regularly changed to ensure maximum efficiency. You might feel cold air blowing from an oil heater if the system is unable to filter the air that moves through it. A blocked filter will create enough resistance that your heater is unable to expel the leftover cold air and will try to push it into your home.

If you’ve gone through troubleshooting for your heater and simply can’t find the answer, it may be time to call a professional. There are problems that can occur in the machinery or electric work that only an experienced technician can handle.

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