Why Your Pilot Light Keeps Going Out & How to Fix It Fast

Why Your Pilot Light Keeps Going Out

If your furnace pilot light keeps going out, you’re dealing with a common but frustrating problem. A pilot light that won’t stay lit can leave your home cold and uncomfortable. The most common causes include dirty components, thermocouple problems, drafts, gas supply issues, or a faulty gas valve. In many cases, you can fix a pilot light that keeps going out yourself with simple cleaning or adjustments. However, some causes require professional help to ensure your furnace operates safely. Understanding why this happens is the first step to getting your heat back on and keeping your home warm.

Common Causes	Possible Solutions	DIY or Professional?
Dirty pilot opening	Clean with compressed air or soft brush	DIY
Faulty thermocouple	Reposition, clean, or replace	DIY with caution
Drafts near furnace	Seal openings, check venting	DIY
Gas supply problems	Check gas valve, supply line	Professional recommended
Faulty gas valve	Replace valve	Professional only

Understanding Your Furnace’s Pilot Light

Before we dive into why your pilot light keeps going out, let’s understand what it actually does. The pilot light is a small, continuously burning flame in your gas furnace. Its job is to ignite the main burner when your thermostat calls for heat. In older furnaces, the pilot light burns all the time. Newer, more efficient furnaces often use electronic ignition systems instead. These systems only create a spark or flame when needed, saving gas and money. When working correctly, your pilot light should show a steady, blue flame. If the flame looks yellow or keeps going out, something is wrong that needs fixing.

Common Reasons Your Pilot Light Keeps Going Out

Dirty Pilot Opening or Orifice

One of the most common reasons a pilot light keeps going out is dirt. Over time, dust and debris can clog the tiny opening where gas flows to create the pilot flame. When this happens, the gas can’t flow properly, and your pilot light may go out. Think of it like trying to drink through a straw that has food stuck in it. The blockage prevents proper flow, and in the case of your furnace, this means an unreliable flame.

Faulty Thermocouple

The thermocouple is a safety device that senses when your pilot light is on. If the pilot light goes out, the thermocouple tells the gas valve to shut off. This prevents gas from leaking into your home. When a thermocouple gets dirty, bent, or worn out, it might not sense the pilot flame correctly. This can cause it to shut off the gas even when the pilot is actually lit. The result? Your pilot light keeps going out for no apparent reason. Sometimes, the thermocouple is just positioned incorrectly. It needs to be in the path of the pilot flame to work properly.

Drafts Near Your Furnace

Air drafts around your furnace can blow out the pilot light. These drafts might come from:

• • Cracks in the furnace room walls

• • Open windows or doors

• • Leaky ductwork

• • Problems with the furnace venting system

Even a small breeze can extinguish the tiny pilot flame, especially if it’s already weak from other issues.

Gas Supply Problems

Your pilot light needs a steady supply of gas to stay lit. If there are issues with gas flow, your pilot light may go out frequently. Common gas supply problems include:

• • A partially closed gas valve

• • Low gas pressure

• • Kinks in the gas line

• • Gas supply interruptions

Sometimes the gas control valve itself is set too low, providing insufficient gas to keep the pilot light burning consistently.

Faulty Gas Valve

The gas valve controls the flow of gas to your pilot light and main burner. If this valve is dirty, worn, or damaged, it might not deliver gas properly. This can cause your pilot light to go out frequently. Gas valves can wear out over time, especially in older furnaces. When they start to fail, they often work intermittently before failing completely.

How to Fix a Pilot Light That Keeps Going Out

Now that we know the common causes, let’s look at how to fix a pilot light that won’t stay lit. Some of these fixes are simple DIY tasks, while others require professional help.

Safety First!

Before attempting any furnace repairs:

• • Turn off the gas supply to your furnace

• • Turn off the furnace power

• • Have a flashlight handy

• • Never force any components

If you smell gas at any point, leave your home immediately and call your gas company from a safe location.

Clean the Pilot Opening

If dirt is causing your pilot light to go out, cleaning may solve the problem:

1. 1. Turn off the gas and power to your furnace

1. 1. Locate the pilot light assembly

1. 1. Gently clean the pilot opening with compressed air or a soft brush

1. 1. Be careful not to damage any components

1. 1. Restore gas and power, then relight the pilot

This simple cleaning often resolves pilot light problems, especially in dusty homes or if your furnace hasn’t been maintained recently.

Fix Thermocouple Issues

If your thermocouple is causing problems, try these solutions:

• • Reposition it: Make sure the thermocouple tip is properly positioned in the pilot flame

• • Clean it: Gently clean the thermocouple with fine sandpaper or steel wool

• • Replace it: If it’s bent or damaged, a new thermocouple might cost about $15-$30 at hardware stores

Replacing a thermocouple is a moderate DIY job. If you’re not comfortable doing it yourself, a professional can handle it quickly.

Eliminate Drafts

To prevent drafts from blowing out your pilot light:

• • Check for air leaks around your furnace room

• • Seal any cracks or gaps in walls or windows

• • Ensure the furnace vent system is properly sealed

• • Keep the furnace room door closed

Sometimes simply closing a window or sealing a crack can solve your pilot light problems.

Check Gas Supply

For gas supply issues:

• • Make sure the gas valve to your furnace is fully open

• • Check for kinks in the gas line

• • If you have other gas appliances, see if they’re working properly

Gas pressure problems usually require professional help. If all your gas appliances are having issues, contact your gas company.

When to Call a Professional

While some pilot light issues are DIY-friendly, others require professional help. Call a heating technician if:

• • You’ve tried the above solutions and your pilot light still goes out

• • You smell gas at any point

• • Your furnace is making unusual noises

• • You suspect the gas valve is faulty

• • You’re not comfortable working with gas appliances

A professional can diagnose complex problems and make repairs safely. They also have specialized tools to test gas pressure and electronic components.

Preventing Future Pilot Light Problems

To keep your pilot light burning reliably:

Schedule Regular Maintenance

Annual furnace maintenance by a professional can prevent many pilot light problems. During a tune-up, technicians will:

• • Clean all components, including the pilot assembly

• • Check the thermocouple

• • Test gas pressure and connections

• • Ensure proper airflow

This preventive care keeps your furnace running efficiently and reliably.

Keep Your Furnace Area Clean

Dust and debris are enemies of your pilot light. Keep the area around your furnace clean and free of clutter. This reduces the amount of dust that can enter the system and clog the pilot opening. Avoid storing cleaning supplies, paint, or other chemicals near your furnace. These can create fumes that affect combustion.

Replace Aging Components

If your furnace is older, consider proactively replacing components like the thermocouple before they fail. This is especially important before winter when you rely on your heating system the most.

Understanding Newer Ignition Systems

If your furnace was made after 2010, it might not have a traditional standing pilot light. Newer furnaces often use:

• • Intermittent pilot ignition: Creates a spark to light the pilot only when heat is needed

• • Hot surface ignition: Uses an electric heating element instead of a flame

• • Direct spark ignition: Directly ignites the main burner without a pilot

These systems are more efficient but can have their own issues. If you have ignition problems with a newer furnace, the troubleshooting steps may be different.

Frequently Asked Questions

Is it dangerous if my pilot light keeps going out?

It can be. While modern furnaces have safety features to prevent gas leaks, a pilot light that repeatedly goes out could indicate problems that might lead to gas buildup or incomplete combustion. This could potentially create carbon monoxide risks. It’s best to address the issue promptly.

How much does it cost to fix a pilot light that keeps going out?

If you DIY the repair, replacement parts like a thermocouple cost $15-$30. Professional service calls typically range from $75-$200, depending on your location and what needs fixing. More complex repairs involving the gas valve might cost $300-$500.

Can I relight my pilot light myself?

Yes, in most cases. Your furnace should have lighting instructions on a label attached to it. Typically, you’ll turn the gas control knob to “Pilot,” hold down the reset button, and use a long lighter to ignite the pilot. Hold the reset button for about 30 seconds before releasing.

How often should I clean my pilot light?

As part of annual furnace maintenance. If you live in a very dusty area or have construction happening in your home, you might need to check it more frequently.

Why does my pilot light go out only at night?

This often happens because temperatures drop at night, causing your heating system to work harder. It could also be related to increased drafts at night or pressure changes in your gas supply. If it only happens at night, drafts are the most likely cause.

Fix Your Pilot Light And Keep Your Home Cozy

A pilot light that keeps going out is frustrating but usually fixable. In many cases, simple cleaning or adjusting the thermocouple will solve the problem. Remember that regular maintenance is the best way to prevent pilot light issues in the first place. If you’ve tried the DIY solutions in this guide without success, it’s time to call a professional. Gas furnace repairs can be complicated and potentially dangerous if not done correctly. For expert help with furnace pilot light issues or any heating concerns, contact Acadiana Comfort. Our trained technicians can diagnose and fix your furnace problems quickly and safely, ensuring your home stays warm all winter long. Call today to schedule an appointment and put an end to those frustrating pilot light problems!