With a gas furnace, your home is set for winter comfort here in Jackson. Gas furnaces are a reliable, efficient way to heat your home during the coldest months of the year. However, like all HVAC systems, there are common furnace issues you should be on the lookout for.

In this article, we’ll review the most common gas furnace repairs and how you can take steps to avoid problems with your system.

Here are the most common gas furnace problems homeowners face.

From issues with the blower belt to a circuit board malfunction, here are the common furnace issues, how much they cost to repair, and how they may be prevented:


What are the most common gas furnace repairs?

Cracked Heat Exchangers

A gas furnace’s heat exchanger is arguably its most important component. The heat exchanger serves as a barrier, separating the combustion chamber and its gases from the intake air that it warms and then blows back into your home. This constant heating and then cooling off causes the metal to warp and expand. With enough time, the heat exchanger may crack. Unfortunately, this is a relatively costly repair to make, running most homeowners between $1,500 and $2,000.

Some homes may be at greater risk of their heat exchanger cracking if the installed gas furnace is too large for the space or there are air intake issues.

Frayed Blower Belt

The blower belt is what keeps the furnace’s blower moving. It’s constantly in motion and accumulating wear-and-tear. With enough time, the rubber in the belt will start to peel and fray. Homeowners typically first notice there’s a problem when the furnace starts making strange noises. However, a damaged blower belt can eventually lead to the gas furnace no longer working altogether.

You can prevent blower belt issues by scheduling a seasonal heating tune-up with our team. As part of our maintenance, our technicians inspect the blower belt to check that it remains in good condition. If the blower belt is damaged or deteriorating, replacing it is relatively inexpensive, so it’s in your best interest to act fast and act early if our technician recommends getting a new one in place.

Furnace Circuit Board Failure

Think of the furnace circuit board as the “brains” of the system. It communicates with the thermostat and turns the furnace off-and-on. A failed or damaged circuit board typically means that the system isn’t heating your home, and that you will need to replace this component to get the furnace running again. The cost of a new circuit board depends on the age of your system and the make and model. Newer, more sophisticated furnaces generally have more expensive circuit boards.

The good news is that most furnace circuit boards are covered by the industry’s general 10-year manufacturer’s warranty. If the board fails within the first decade after installation, it may be replaceable under the condition of the warranty. However, there’s an important catch: many of these warranties have a clause that requires homeowners to keep up with annual maintenance if they want the warranty to remain in effect. Among other reasons, this is why skipping seasonal furnace maintenance is a bad idea for your home.

Flame Sensor Malfunction

Finally, there’s the flame sensor. The flame sensor, true to its name, senses whether or not there is a flame in the furnace, which means successful combustion is occurring. If the system is releasing gas but there is no combustion, the flame sensor shuts down the furnace. This is an important safety feature: if the flame sensor is no longer operable or has been damaged, it may either not function or may “cry wolf” and shut down your furnace even when there’s no problem.

During a tune-up, our technicians will take a look at the sensor to make sure there’s no visible signs of damage. Typically, flame sensors show signs of wear-and-tear—such a cracked ceramic or burn marks—prior to failure, so a visual inspection is key. If the flame sensor does need to be replaced, our technician will recommend that as a course of action: flame sensors generally cost between $100-$200.

As a final note, every home should also have a carbon monoxide detector located near their gas furnace. In the unlikely event that the flame sensor stops working but the furnace continues operating and building up gas, the carbon monoxide detector serves as a second line of defense, ensuring that no furnace gases are leaking out of the system and into your home.

See the most common gas furnace issues: