A properly functioning heater is necessary during cold Vineland, New Jersey winters. If your furnace is pushing out cold air, it’s a sign that something is malfunctioning. It could be a simple fix or a sign that you need a new furnace. Here are some reasons why your furnace may be blowing out cold air.

A Damaged Pilot Light

The pilot light is a small flame used to ignite your gas furnace. It provides a consistent source of ignition for the burner. The pilot light ignites the burners in your unit, allowing it to create heat. You can typically find your furnace’s pilot light at the bottom of your heater, near the front of the unit. You may need to remove a small access panel to see the pilot light. On some models, it’s visible through a small window in the furnace.

Pilot lights can go out for several reasons, the most common being the wind blowing them out. However, a leak or blockage in your furnace can also cause the pilot light to go out. Frequent pilot light outages should be reported to an HVAC technician for troubleshooting, maintenance, or repair.

A Dirty Flame Detector

The flame detector or flame sensor is a safety device on your furnace that detects if the heater is producing a flame or burning gas. On most units, the flame detector is a rod that sticks out where the flame comes from the burners. It always sits on the opposite side of the igniter.

When the burners create a flame, the flame detector sends an electrical signal to the furnace’s control board. This signifies that everything is functioning correctly, and the heater can continue to supply gas to the burners.

However, if a flame isn’t detected, an electrical signal isn’t sent to the control board, and the system shuts down just a couple of seconds after opening the gas valve. This prevents unburned gas from entering your home, creating a potentially dangerous situation.

Over time, your flame sensor can get covered with dirt and soot, making it difficult for the sensor to detect the heat from the flame. Your furnace will turn off the gas, but your blower fan will continue to blow, pushing cold air through the house. If you feel that your flame sensor is the culprit, the HVAC technicians at Laury Heating Cooling & Plumbing can inspect, clean, or replace it if necessary.

Air Filter Is Restricting Airflow

A dirty furnace filter can block incoming air from your gas furnace. Symptoms of a dirty air filter include long heating cycles and issues with overheating. If your furnace has an overheating problem, it can cause cold air to blow through your home. A great way to prevent this issue is by replacing your air filter with a new one based on the manufacturer’s recommendations.

Also, you want to have the right filter for your HVAC system. If you have a filter with a higher MERV (minimum efficiency reporting values) rating, the denser the filter will be, further restricting airflow.

Using a filter with a higher MERV rating is fine if you have the right filter for your unit, as your unit will have the power to keep air moving and pushing through the denser filter material. However, if you use a pleated air filter that’s too dense for your unit, its operation will be less efficient. It could also damage your system, or it may result in your system blowing cold air.

Low Supply of Gas in the Home

A furnace that’s blowing cold air could indicate an issue with the gas supply line in your house. As a safety feature, modern furnaces will deactivate if they’re not receiving sufficient gas to perform their standard process. It’s not easy nor safe for a homeowner to attempt to fix an issue with gas flow. It’s recommended to call a professional HVAC technician to repair the furnace.

Damaged Ductwork

Your furnace might be blowing cold air because there are holes or cracks in your home’s ductwork. Openings in your large or small ductwork can allow cold air from the attic into your air ducts. Your heater might be working as it should. However, the hot air it produces leaks before it can blow out of your vents. Properly inspecting and sealing your ductwork can allow warm air to reach the vents in your house.

Clogged Condensate Lines

If you’ve examined the indoor unit of your HVAC system, you’ve probably seen a large pan sitting underneath it. This drain pan captures water that drips from your HVAC system. Those water drips are collected and carried away via a drain line at the bottom of the pan. However, it can be a severe problem when this condensate line becomes clogged with debris, dirt, dust, pet hair, and other items.

In modern furnaces, if the condensate line becomes blocked, a sensor is activated that turns off the burners. Since the blower fan continues to function, this will cause cold air to be blown into your home.

The Thermostat Is Set to “On”

If your heater is blowing cold air, check your thermostat settings and confirm that it’s on “automatic.” When the thermostat is set to “automatic,” the blower fan will only function when the furnace is burning and there’s warm air circulating through the home. If the blower is set to “on,” the blower fan is constantly going and will circulate cold air when the furnace isn’t producing heat.

Faulty Control Board

The control board of your furnace serves as its brain. When the circuit control board gets a heating signal from the thermostat, it signals the furnace burner and blower. If the circuit board isn’t working right, it might signal the blower but not the burners. So, the blower will be pushing cold air throughout your house. There are several reasons why circuit boards could fail. Many of them have to do with a lack of cleaning and maintenance.

Cracked Heat Exchanger

A cracked heat exchanger can cause cold air to blow from the vents when the heater is on. When a heat exchanger is cracked, it could lead to the unit overheating, causing safety sensors to trigger and turning off the burners. In addition to causing a furnace to blow cold air, a cracked heat exchanger could put your household at risk of carbon monoxide poisoning.

Working With Experienced HVAC Technicians in South Jersey

At Laury Heating Cooling & Plumbing, we’re proud to work with our customers, helping them to enhance their home’s HVAC systems and plumbing. For more than seven decades, our team has focused on having high standards, providing professional service, and offering the best warranties in the business.

Our services include HVAC installation, repair, and maintenance in South Jersey. We also install ductless mini splits and offer natural gas conversions. We even provide plumbing services, water heater installations, drain cleaning, water pipe repair, sewer lines maintenance, and general plumbing. Contact Laury Heating Cooling & Plumbing today and see for yourself what makes us so different from the rest.

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