Your Furnace Won't Ignite: Now What?

Furnaces rely on an intricate system to heat a home. A large part of the cycle is the ignition process. When the furnace doesn't ignite, the heating process can't initiate — which means your home stays cool. Typically, there is a specific reason why a furnace won't ignite; you just have to figure out the problem. Here are some of the common reasons why a furnace won't ignite, and what you can do about the problem.

Clogged Filter

Heating systems rely heavily on airflow. Not only does the system function by cycling warm air out of the system, but it also relies on airflow throughout the system. As a result, a lack of airflow can cause the furnace not to function correctly.

A leading reason for airflow problems is a clogged air filter. In the same manner that you must regularly change the air filter in your cooling system, you must also change the filter in your heating system. When the filter clogs, the issue limits the amount of air that is able to flow through the system, which typically leads to problems. 

Closed Supply Line

A furnace will generally have a gas supply line. The gas supply line is responsible for distributing the fuel supply to the furnace in order for the system to operate. There are some instances when the valve might close, especially if you perform maintenance to the furnace on your own and don't know exactly what you're doing. 

If the valve is closed, don't try to open it on your own. You run the risk of damaging the line, which could cause gas to leak from your furnace. Allow a professional to address the matter for you. 

Pilot Light Problem

The pilot light is the mechanism by which the furnace ignites so a problem with the pilot light will always lead to heating concerns. However, a problem with the pilot light isn't always the easiest to spot. Typically, the furnace will still power on like it normally would, but you might hear a clicking noise and of course, the system won't produce heat.

Pilot problems arise for many different reasons, including a problem with the sensor. Similar to a gas line issue, it's always best to leave the matter to a professional. If you attempt to replace the sensor, you could cause significant damage to the furnace.

If you're unable to discover the reason for the furnace failure or you can't investigate the matter safely, contact a repair technician for further assistance. Visit a site like for more info.