It can be a real inconvenience when your furnace starts to blow cold air during winter. It’s important to determine the cause and fix it as soon as possible to make your home comfortable again. There are several potential causes for a furnace blowing cold air, and each one requires a different solution.

Incorrect Thermostat Settings

The thermostat is essential in defining the right temperature range for your home’s comfort. Therefore, you must check the thermostat if you immediately note the furnace blowing some cold air. One common reason is that someone set the thermostat to “cool” instead of “heat.” If you set the thermostat to “cool,” the furnace will blow cold air. Another possibility is that you set the thermostat too low. In this case, the furnace will turn on, but it won’t be able to reach the temperature you’ve set it at, so it will continue to blow cold air.

Damaged Ductwork

Over time, the ductwork that carries heated air from your furnace to the different rooms in your home can become damaged by developing holes and cracks. This can happen due to several factors, including animal nesting, inadequate insulation and bad installation. The small and large openings in the duct system can allow heat to escape before it can reach your rooms, resulting in cool air coming from the furnace. Consequently, they can also allow cold air from outside to enter the ductwork.

The Pilot Light Is Out

If you have a gas furnace, it uses a pilot light to ignite the gas that powers the burners. The pilot light is a small flame that ignites the burner in the furnace, which in turn heats the air. If the pilot light goes out, the burner will not be able to produce heat. There are a few reasons why the pilot light may have gone out. One possibility is that a draft has blown it out. It’s also possible that the pilot light igniter may be dirty, or someone turned the gas supply to the furnace off.

Your Furnace Takes Time to Heat Up

A furnace system consists of several moving parts that do not instantly respond to a thermostat’s signal. Therefore, when the furnace switches on, everything requires some time to heat up. For the air in your home to feel warm, the furnace has to heat up. This process can take a few minutes, during which you may experience cold air from the vents. Once the furnace is up to temperature, it will start blowing hot air. This delay usually happens if no one’s used the furnace for a substantial period. If your furnace blows cold air, wait a few minutes, and it should start blowing hot air.

Dirty Air Filter

A possible reason your furnace might be blowing cold air is a dirty air filter. The air filter is responsible for trapping dirt, dust, and other airborne particles; over time, it can become clogged with debris. When this happens, airflow is restricted, and the furnace has to work harder to draw in air. As a result, the furnace may not be able to generate enough heat to warm your home. In the long run, the airflow obstruction makes the furnace system overheat, causing it to shut down.

Condensate Lines Are Clogged

Clogged condensate lines can also cause cold air to blow from the furnace. Your furnace produces water vapor as a by-product of the combustion process. This water vapor condenses on the heat exchanger and drips into a drain pan. From there, it is supposed to be drained out of your home through the condensate line to prevent the development of rust. If this pipe becomes clogged, the water will back up and overflow into your furnace, causing the furnace to shut down and instead blow cold air.

Weak Fuel Source

You may notice that your furnace is blowing cold air if the temperature in your home starts to drop suddenly, especially if your furnace uses natural gas to create heat. If the gas supply is not strong enough, the burner will not be able to produce enough heat to warm the air. The furnace will deactivate as a safety measure and blow out cold air instead.

If your Omaha furnace is blowing cold air, Xtreme Heating & Cooling LLC can help. We have an experienced team of experts who can assist you with all your heating and cooling needs. We also provide indoor air quality services and can work on commercial HVAC systems. Contact us today for more information or to set up an appointment.

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