Before you know it, the temperatures in Oklahoma City will be dropping low enough for you to run the furnace in your home. On cold nights, it can be easy to take your furnace for granted. However, if your furnace suddenly starts blowing cold air, it won’t be long until your house becomes uncomfortable and your furnace becomes your top priority. That’s why it’s important to understand the possible causes of cold air coming from your furnace so that you can respond quickly to minimize your discomfort. To help you through this tough situation, here are a few insights from the pros at All Tech Heat & Air.

Simple Things First

If your furnace is blowing cold air, it’s important to check the simple things first. Specifically, make sure that your thermostat is set to the “heat” setting. If the fan is set to the “on” position and the system is set to the “off” position, your fan could be circulating air throughout your home without your furnace running to warm the air as it circulates. It’s also possible that the battery in your thermostat died while the system was operating. Depending on how your system is set up, this may trigger your furnace to shut down automatically without sending the same signal to your blower fan.

Dirty Air Filter

Another reason your furnace might shut down is if you have a dirty air filter. In some ways, your furnace depends on you just as much as you depend on your furnace. To properly operate, your furnace needs cool air from your home to help regulate its temperature. However, if the air filter is dirty, less cool air will flow through the system, causing the furnace to overheat. Fortunately, the furnace has a temperature sensor to prevent it from getting so hot that it causes a fire. Unfortunately, when this sensor shuts the furnace down, your blower fan will likely continue to operate, resulting in cool air circulating throughout your home. To prevent this problem, All Tech Heat & Air recommends inspecting your air filter every month. If you find that the filter is dirty, be sure to replace it with a new filter.

Broken Draft Inducer

One of the biggest risks of gas furnaces is having unburned natural gas or combustion gases come into your home. To prevent this, every gas furnace is equipped with a draft inducer to ensure the gases escape through the flue instead of reversing back into your home. To ensure there is adequate ventilation into a cold flue, the draft inducer is one of the first pieces of equipment to turn on when the heating cycle begins. If the draft inducer malfunctions, sensors in the furnace will prevent it from turning on. With the blower fan running and the furnace stopped, you will have cold air blowing from your home’s vents.

Gas Supply Interruption

Before the natural gas that powers your furnace arrives in your home, it has to travel through a complex system of underground pipes. At any point along this path, a pipe could have a problem that could cause an interruption to your home’s gas supply. When your furnace turns on, one of the checks it does is to make sure that gas is flowing to the burners. If there’s no gas, the pilot light won’t engage and the furnace won’t turn on. This helps protect the pilot light, burners, and other system components. With no burners igniting to produce a flame to heat the heat exchanger, you’ll quickly notice cold air coming into your home.

Pilot Light Not Working

Far more common than a gas supply interruption is a faulty pilot light. The pilot light is the flame or spark responsible for igniting the natural gas that flows into the burners. If you have an always-on pilot light, All Tech Heat & Air recommends checking to see if your pilot light has gone out if your system is blowing cold air. If it has, you can try to relight it according to the manufacturer’s instructions. If you can’t get it to relight, or it doesn’t stay lit after you light it, it’s likely that the thermocouple in your furnace is either dirty or faulty. The good news is that your furnace won’t allow gas to flow to the burners if it senses a problem with the pilot light. The bad news is that this problem could leave you with cold air blowing into your home.

Problem With Flame Sensor

If the pilot light and burners are working correctly, you might still get cold air blowing in your home if there’s a problem with the flame sensor. The flame sensor is the sensor that can shut off the flow of gas to the burners if the burners aren’t producing a flame. Unfortunately, if the flame sensor becomes dirty, it might fail to detect that there’s a flame, even if one is present. This will stop the flow of gas to the burners, thus extinguishing the flame and causing the warm air coming through the vents to transition to cold air. Fortunately, a technician from All Tech Heat & Air can easily test your furnace’s flame sensor to see if it’s the culprit of your cold-air problems. If it is, they can clean or replace it quickly and easily.

Major Problem With Ducts

Of course, there could be times when your furnace is working perfectly, but you’re still noticing cold air blowing into your home. If that describes your situation, one potential culprit is your home’s ducts. Typically, conditioned air leaves the furnace and travels to the vents without losing too much heat energy. However, if your home’s ducts are clogged, leaky, or poorly insulated, the temperature of the air could drop significantly before it reaches its final destination. To check for duct problems, a technician from All Tech Heat & Air can put a camera into your vents. If the ducts are clogged, duct cleaning will remove the dust and debris to restore adequate airflow. For leaky ducts, the holes or gaps in the ducts can be patched to prevent cold air from leaking into the ducts. You can correct poorly insulated ducts in a variety of ways depending on the location of the ducts.

Bad Heating Element

For the most part, this guide has focused on gas furnaces. What if you have an electric furnace, though, and you’re having problems with the furnace blowing cold air? A likely culprit in this situation is a problem with one or more of the furnace’s heating elements. These are coils of wire that are resistant to electricity. Over time, the metal in the heating elements can become brittle as it goes through hundreds of rapid temperature changes. Eventually, this can cause the heating element to break, preventing the furnace from operating properly. Depending on the furnace, you may be able to replace the heating element, or you may need a new furnace from All Tech Heat & Air.

Furnace Repair on the Coldest Days

At All Tech Heat & Air, we understand that home comfort is a high priority when it’s cold outside. That’s why we work hard to provide top-notch air conditioner installations, furnace repairs, geothermal system installations, and much more. With over 20 years of service under our belts, you can be confident that we’ll treat you with professionalism and respect every time you give us a call. That’s why we’re able to maintain an A+ rating with the Better Business Bureau and continually receive five-star customer reviews. To learn more about repairing furnace problems, contact us at All Tech Heat & Air today.

Dan Addi
Dan Addi

Director of Operations

Dan Addi is the Director of Operations for All Tech Heat & Air, and has 20 years of experience.
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