Why Does My Furnace’s Pilot Light Keep Going Out?

Your pilot light is the core of your furnace’s functionality. Without it, there can be no ignition and no heat. New furnaces rely on electronic ignition systems, but if your HVAC system was installed before 2010, you’ll still need your pilot light to burn continuously. If your equipment doesn’t remain lit, it could mean:

• Your gas supply is obstructed.
• Your thermocouple is dirty or damaged.
• The pilot light is covered in soot or debris. 
• You have a draft.
• Your gas regulator is faulty. 

The Age of Your Heating System

Your intake valve can attract a surprising amount of dirt as it ages. If you’ve neglected annual maintenance, your aging heat exchanger might develop cracks that expose your pilot light to drafts. Mechanical damage can also alter your air pressure and reduce the ventilation in your combustion chamber. The average life expectancy of a furnace is 15 to 20 years. If your system has passed its prime, a replacement could be more cost-effective than a repair. The general rule of thumb is to opt for replacement if the required repair costs more than half the price of a new furnace. 

The Condition of Your Heating System 

Your heating system is responsible for warming the air before distributing it via your ductwork. The heat exchanger supports this process by moving air through tubes or coils. Cracks can expose your pilot light to too much air, but they can cause an even bigger problem: carbon monoxide poisoning. Your furnace is prone to blockages, rust, and debris that can only be mitigated through an annual service. Preventative maintenance will clear away clogs, remove soot deposits, and replace a defective thermocouple.

Gas Valve & Supply Problems

Your pilot light can only burn if it has access to a continuous gas flow. A dirty or damaged gas valve could be causing all your problems. However, before you assume you have a mechanical fault, ensure you still have an adequate gas supply. If you still have plenty of fuel, look for red flags like short-cycling and safety shutoffs. These symptoms can indicate a faulty valve that can cause a carbon monoxide hazard. 

Thermocouple Malfunction

Your thermocouple alerts you when your pilot light is out, but sometimes, it can cause ignition loss. This equipment connects to your gas valve and keeps it open. Dirty thermocouples can cause inaccurate readings and shut off your gas supply before it reaches your furnace. Loose wires can cause similar problems. Thermocouples aren’t designed to last as long as your furnace, so you’ll need to replace yours regularly during your annual service. 

Poor Venting & Airflow 

If your pilot light tends to go out on windy days, you have an airflow problem. Flames need a good air supply to remain lit, but too much airflow can blow them out completely. A faulty intake air register can have a vacuum effect, so you may also have a blockage. If your pilot light is flickering rather than turning off completely, you probably need more airflow. This can also cause a yellow, wavering, or split flame. A vent blockage can cause the same problem. 

Is it safe to relight your own pilot light? 

If you use the right precautions, it’s usually safe to relight your own pilot light. Hold down the reset button while relighting the flame. Even so, an undiagnosed pilot light problem can be a hazard. If your light goes out due to a gas valve flaw, your home may be exposed to a carbon monoxide leak, so it’s best to request professional support. 

Trust Total Air With Your Furnace Repair

Total Air and Heat is a family-owned business that truly cares about your comfort. Our team is certified and completes two manufacturer’s training courses annually to provide the best pilot light support in the industry. If you aren’t comfortable, we aren’t comfortable. 

Don’t try to manage pilot light niggles alone. Call Total Air and Heat at 972-881-0020 or contact us online.