The dark, chilly winter months need not be awful if you have a lovely warm home to return to after a day outside. If your heating system breaks down in the dead of winter, your warm and inviting bedroom will be of little use. Here are a few of the most prevalent furnace issues in cold weather.

Duct Filter Clogged Up

It’s surprising how often dirty furnace filters are at the root of technical difficulties. It is commonly believed that this is the primary reason furnaces break down. If the filter in your heater is clogged, the airflow will be diminished. The decreased airflow will force your heating system to operate for longer than necessary. Problems with the furnace can manifest in a variety of ways under these settings. Easily remedied by swapping out the air filter in your heater.

No heat/airflow consistency

Again, the blocked or extremely unclean filters might be the underlying cause of some of the most typical furnace difficulties in cold weather. However, there will be moments when the control board keeps malfunctioning. Even when the thermostat calls for heat, it occasionally stops working or only blows cold air or has an uneven air flow. This is especially true in the winter. The heat request, the heat pump, and the auxiliary heating system are all inoperable. In this case, it may be possible and inexpensive to just replace the furnace’s control board. It’s possible that your furnace’s power has been switched off because a circuit breaker has tripped. Make sure all circuits are turned on by checking the breaker box.

Damaged Heat Exchanger

A malfunctioning heat exchanger is usually the most severe issue one can encounter when dealing with furnace problems during the winter season.   The purpose of the heat exchanger is to separate the heated flame from the air inside your home.   The heat exchanger in your furnace is warmed by the fuel from your heating system, and then the warmth is spread throughout your home using ductwork.   When a cold front passes, it frequently leads to an increase in temperature that exceeds expectations.

Given the frequency of heat exchanger cracks, it is strongly recommended by HVAC technicians to promptly replace the furnace in such cases.

Issues with the Intermittent Pilot System

This electrical ignition system uses a high-voltage spark when the thermostat triggers the furnace to turn on. The primary burner has a flame detecting rod that lights up when the pilot is lighted. The flame extinguishes at the end of each heating cycle and does not relight until the following cycle begins. Remember that if the furnace’s intermittent pilot mechanism isn’t functioning correctly, the furnace won’t turn on.

Although spark ignition is more frequent in older furnaces, it is still used in certain newer systems. In contrast to conventional hot surface ignition systems, this one requires a pilot light to be lit beforehand. When the board sees that the pilot is glowing, it orders the main burners to ignite. Therefore, everything is done through the gas valve from giving the ignition source to the flame rectification procedure.

Hot Surface Igniter Issues

The hot surface igniter is now the most popular electronic ignition method available. This igniter, often made of silicon nitride or carbide, uses electrical current to heat and ignite your furnace’s gas burners.

The resistance (ohm value) of an igniter rises with its age, shortening its useful life. In a hot surface ignition system, the hot surface igniter cracking is the main issue. Because of this, the gas cannot be set ablaze by the igniter.

Issues with the thermostat

The thermostat is the control center for your heating and cooling system. When your thermostat malfunctions, your complete heating and cooling system typically malfunctions as well. The most common thermostat issue is dead batteries.


After you’ve exhausted all possible self-service options for furnace troubleshooting, it’s best to bring in the experts. Look for a business that specializes in fixing heating, ventilation, and air conditioning systems. Find out how well their treatment holds up during winter.

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