Why Does the Pilot Light in My Gas Furnace Keep Going Out and What Can I Do to Fix It?

The pilot light in a gas furnace is a small flame that lights the main burner. It is crucial for safe and efficient operation. If the pilot light keeps going out, it can be frustrating and inconvenient. This article explores the common reasons behind this issue and provides practical steps you can take to fix it.

Common Causes of a Flickering Pilot Light

There are several reasons why a gas furnace pilot light might keep going out. Here are some of the most common causes:

Faulty or Dirty Thermocouple: The thermocouple is a safety device that ensures the gas supply is properly turned off when the pilot light goes out. A dirty or faulty thermocouple can cause the pilot light to go out frequently. Weaker Pilot Flame: Over time, the pilot flame can get weaker, making it more susceptible to being blown out by drafts or air currents. Excessive Draft: If there is too much air flow around the furnace, it can blow out the pilot light. Obstructed Gas Line or Orifice: In some cases, condensation, water, or rust particles may accumulate, blocking the gas supply to the pilot. Aged Automatic Pilot Igniter: If your furnace is equipped with an automatic pilot igniter, its age or malfunctions may cause the pilot light to go out.

Steps to Troubleshoot and Fix the Problem

Before calling a professional, there are several DIY troubleshooting steps you can take to address the issue:

Cleaning the Thermocouple

Disconnect the pilot control valve and examine the thermocouple. A build-up of dirt or debris can cause it to malfunction. Use a soft brush or a cotton swab to clean the thermocouple. Make sure to follow the manufacturer's guidelines when performing this step.

Adjusting the Pilot Flame

Ensure that the pilot flame is properly adjusted. A weak or uneven flame can cause the thermocouple to give false signals, leading to frequent pilot light failures. Consult the furnace's manual for the correct flame adjustment procedure.

Checking for Obstructions

If the pilot light is located in the basement, check for condensation or water in the gas line. If there is water or rust particles blocking the orifice, you might need to disassemble the pilot to remove the dirt. Install a particle trap to prevent future blockages.

Professional Inspection and Repair

If these steps do not resolve the issue, it is best to have a professional HVAC technician inspect the furnace. They can identify any issues that may be causing the pilot light to go out and make necessary repairs to ensure safety and efficiency.

Additional Precautions and Safety Measures

It is vital to take additional safety measures when dealing with gas appliances:

Carbon Monoxide Detection: Install carbon monoxide detectors in the basement and other areas where the pilot light is located. Regularly check for any signs of carbon monoxide poisoning. Proper Ventilation: Ensure that the furnace and other gas appliances are properly vented to the outside. This prevents the accumulation of harmful gases like carbon monoxide. Utility Company Inspection: Contact your local utility company to perform an inspection of the gas lines and appliances. They can identify any issues and provide recommendations for safe operation.

Remember, while it may seem like a small issue, a faulty pilot light can have serious consequences, including carbon monoxide poisoning. Therefore, it is important to address these problems promptly and effectively.

Conclusion

A gas furnace's pilot light can be a critical component for safe and efficient operation. Understanding the common causes of frequent pilot light failures and taking proactive steps to address them can help you resolve the issue. If necessary, don't hesitate to seek professional help to ensure the safety and reliability of your furnace.