Pilot Light On Furnace Won’t Stay Lit: Troubleshooting Tips

Water Heater Troubleshooting Pilot Won't Stay Lit Repair and
Water Heater Troubleshooting Pilot Won't Stay Lit Repair and from www.youtube.com


Having a pilot light that won’t stay lit on your furnace can be frustrating, especially during the colder months. A pilot light that keeps going out can prevent your furnace from functioning properly, leaving you in the cold. In this article, we will discuss some common reasons why your pilot light might not stay lit and provide you with troubleshooting tips to help you resolve the issue.

1. Gas Supply Issues

One of the most common reasons why a pilot light won’t stay lit is due to a problem with the gas supply. Check if the gas valve is open and ensure that there is an adequate supply of gas to the furnace. If you suspect a gas leak, it’s important to contact a professional immediately for assistance.

2. Thermocouple Problems

A faulty thermocouple is another common cause of pilot light issues. The thermocouple is a safety device that detects whether the pilot light is lit or not. If it senses that the pilot light is out, it will automatically shut off the gas supply. Over time, the thermocouple can become dirty or worn out, causing it to malfunction. Cleaning or replacing the thermocouple can often solve the problem.

3. Dirty Pilot Orifice

A dirty pilot orifice can also prevent the pilot light from staying lit. The orifice can become clogged with dust, debris, or rust, obstructing the flow of gas. Carefully clean the pilot orifice using a small wire brush or compressed air to remove any obstructions.

4. Drafts and Ventilation

Drafts or poor ventilation can disrupt the flame of the pilot light, causing it to go out. Check for any drafts near the furnace and ensure that the area around the furnace is properly ventilated. Consider sealing any gaps or cracks in the furnace room to prevent drafts.

5. Faulty Gas Valve

If none of the above solutions work, it’s possible that the gas valve itself is faulty. The gas valve controls the flow of gas to the pilot light and main burner. If the gas valve is defective, it may not allow the pilot light to stay lit. In this case, it’s best to contact a professional HVAC technician to inspect and replace the gas valve if necessary.


A pilot light that won’t stay lit can be a frustrating issue to deal with. By following the troubleshooting tips mentioned in this article, you can identify and resolve the problem causing the pilot light to go out. However, if you are unsure or uncomfortable performing these troubleshooting steps on your own, it’s always recommended to seek professional assistance to ensure the safety and proper functioning of your furnace.


The information provided in this article is for informational purposes only and should not be considered as professional advice. Always consult a qualified HVAC technician for accurate diagnosis and repair of your furnace.