Why Your Pilot Light Keeps Going Out
When your pilot light keeps going out, it usually means there’s a problem with your gas furnace or water heater. The most common causes include dirty components, faulty thermocouples, drafts, gas supply issues, or a clogged orifice. You can often fix this yourself by cleaning the pilot assembly, checking for drafts, or adjusting the gas supply. However, if you smell gas or can’t solve the problem after basic troubleshooting, it’s time to call a professional. A working pilot light is essential for your heating system to function properly and keep your home warm.
Table of Contents
| Common Causes | Possible Solutions | When to Call a Pro |
|---|---|---|
| Dirty pilot assembly | Clean with compressed air | If cleaning doesn’t work |
| Faulty thermocouple | Reposition or replace | If replacement is needed |
| Drafts near unit | Block air sources | If drafts can’t be controlled |
| Gas supply issues | Check gas valve | For any gas line problems |
| Clogged orifice | Clean carefully | If clog persists |
Understanding How Pilot Lights Work
A pilot light is a small flame that stays lit all the time. It serves as the ignition source for your furnace or water heater’s main burner. When your thermostat calls for heat, gas flows to the main burner and the pilot light ignites it.
Modern systems often use electronic ignition instead of standing pilot lights. These systems only create a spark or flame when needed, which saves energy. But many older furnaces and water heaters still use traditional pilot lights.
The pilot light works with a safety device called a thermocouple. This metal rod sits in the pilot flame. When heated, it generates a small electrical current that keeps the gas valve open. If the pilot light goes out, the thermocouple cools down and signals the gas valve to close, preventing gas from leaking into your home.
Common Reasons Your Pilot Light Keeps Going Out
Dirty Pilot Assembly
Over time, dust and dirt build up in the pilot assembly. This can block the tiny hole where gas comes out. When this happens, the pilot light may not get enough gas to stay lit.
You might notice the flame looking yellow or orange instead of blue. A healthy pilot flame should be blue with a small yellow tip. If it’s mostly yellow, that’s a sign it’s not burning efficiently due to dirt or poor air-to-gas mixture.
Faulty Thermocouple
The thermocouple is a safety device that senses when your pilot light is on. If it gets dirty, bent, or wears out, it might not sense the flame correctly. When this happens, it can shut off the gas supply even when the pilot is actually lit.
Sometimes the thermocouple is just out of position. It needs to be directly in the pilot flame to work right. If it’s too far from the flame, it won’t get hot enough to keep the gas flowing.
Drafts Near Your Furnace
Air drafts can blow out your pilot light just like they blow out a candle. These drafts might come from:
– Open windows
– Leaky ductwork
– Cracks in your foundation
– Ventilation issues
Even a small breeze can be enough to extinguish the pilot flame. This is especially common in furnaces located in basements, attics, or garages where there might be more air movement.
Gas Supply Problems
If your pilot light keeps going out, there might be an issue with the gas supply. The gas pressure might be too low, or the gas line might be partially blocked.
Sometimes the gas valve isn’t opened fully. This can happen after maintenance or if someone accidentally bumps the valve. Check to make sure the valve is in the fully open position.
Clogged Pilot Orifice
The pilot orifice is a tiny opening where gas flows out to create the pilot flame. It can get clogged with dirt, debris, or even spider webs. When this happens, not enough gas reaches the pilot light.
Because the opening is so small, even a tiny amount of dirt can cause problems. Regular cleaning can prevent this issue from happening.
How to Fix a Pilot Light That Keeps Going Out
Safety First!
Before you start any work on your furnace or water heater:
– Turn off the gas supply to the appliance
– Make sure there are no gas smells in the area
– Have good ventilation
– Keep a fire extinguisher nearby
Never force any parts or use excessive pressure when working on gas appliances. If you smell gas at any point, leave your home immediately and call your gas company from a safe location.
Clean the Pilot Assembly
Cleaning the pilot assembly often solves the problem. Here’s how to do it:
1. Turn off the gas to your appliance.
2. Wait 10 minutes for any gas to clear.
3. Remove the access panel to reach the pilot assembly.
4. Gently clean the assembly with compressed air or a soft brush.
5. Pay special attention to the small opening where the gas comes out.
Be very gentle when cleaning. The components are delicate and can be damaged easily. Avoid using water or liquid cleaners on the pilot assembly.
Check and Reposition the Thermocouple
If your thermocouple is just out of position, you can fix it yourself:
1. Look at where the thermocouple sits in relation to the pilot flame.
2. It should be directly in the flame, about 1/2 inch from the tip.
3. If it’s too far away, gently bend it closer to the flame.
4. Make sure it’s secure and not wobbly.
If the thermocouple looks corroded or damaged, it probably needs to be replaced. This is a fairly simple job that many homeowners can do themselves, but you can also call a professional.
Eliminate Drafts
To protect your pilot light from drafts:
1. Check for air movement around your furnace or water heater.
2. Close nearby windows and doors.
3. Seal any cracks or openings in the walls or foundation.
4. Make sure the exhaust flue is properly connected and sealed.
Sometimes adding a simple draft guard can help protect the pilot flame. This might be as simple as a small metal shield that blocks air from hitting the flame directly.
Check the Gas Supply
Make sure your gas supply is working correctly:
1. Verify the gas valve to the appliance is fully open.
2. Check if other gas appliances in your home are working normally.
3. Make sure your gas bill is paid and service is active.
If you suspect a problem with gas pressure, you’ll need to call a professional. Only licensed technicians should work on gas lines and pressure regulators.
Clean the Pilot Orifice
If the pilot orifice is clogged, you can try to clean it:
1. Turn off the gas and wait for it to clear.
2. Locate the pilot orifice (the small hole where gas comes out).
3. Use compressed air to blow out any debris.
4. For stubborn clogs, you can use a very fine needle, but be extremely careful not to enlarge the hole.
This is a delicate job, and if you’re not comfortable doing it, it’s best to call a professional. Damaging the orifice can create bigger problems.
When to Replace Parts Instead of Cleaning
Sometimes cleaning isn’t enough, and parts need to be replaced. Here are signs that replacement is needed:
Thermocouple Replacement
Replace your thermocouple if:
– It’s visibly corroded or damaged
– The tip is black or discolored
– You’ve cleaned and repositioned it, but the pilot still goes out
– It’s been in use for more than 10 years
Thermocouples are inexpensive (usually $5-$15) and relatively easy to replace. Many hardware stores carry universal thermocouples that fit most furnaces and water heaters.
Pilot Assembly Replacement
Consider replacing the entire pilot assembly if:
– Multiple cleanings haven’t solved the problem
– The assembly is visibly damaged
– The pilot tube is bent or kinked
– Your appliance is very old and parts are worn out
Pilot assemblies are more expensive than thermocouples (typically $30-$100) and may require professional installation. Always get the exact replacement part for your model.
Modern Alternatives to Standing Pilot Lights
If you’re tired of dealing with pilot light problems, you might consider upgrading to a system with electronic ignition:
Intermittent Pilot Ignition
This system uses a pilot light, but only lights it when the furnace needs to run. When the thermostat calls for heat, a spark lights the pilot, which then lights the main burner. When heating is complete, both flames go out.
This saves gas because the pilot doesn’t burn continuously. It’s more efficient and eliminates many pilot light problems.
Direct Spark Ignition
This system doesn’t use a pilot light at all. Instead, an electric spark ignites the main burner directly. There’s no pilot to go out, which eliminates this common problem completely.
Direct spark systems are very reliable and energy-efficient. They’re common in newer furnaces and water heaters.
Hot Surface Ignition
This system uses an electric heating element that glows red-hot to ignite the gas. It works like the cigarette lighter in older cars. When the furnace needs to run, electricity flows to the igniter, heating it up until it’s hot enough to light the gas.
Hot surface igniters are very common in modern furnaces. They’re reliable but do need replacement every 3-5 years as they can become brittle.
Preventive Maintenance to Keep Your Pilot Light Working
Regular maintenance can prevent pilot light problems before they start:
Seasonal Cleaning
Clean your furnace or water heater at least once a year, preferably before the heating season starts. Pay special attention to the pilot assembly and surrounding areas.
Use compressed air to blow away dust and debris. This simple step can prevent many pilot light problems.
Professional Tune-Ups
Have a professional HVAC technician inspect your system annually. They can:
– Clean parts you can’t easily reach
– Test gas pressure and connections
– Check for safety issues
– Spot potential problems before they cause breakdowns
Professional maintenance typically costs $80-$150 but can save you money by preventing expensive repairs and extending the life of your system.
Monitor Your Pilot Flame
Check your pilot flame occasionally to make sure it looks healthy. A good pilot flame should be:
– Mostly blue in color
– Steady (not flickering)
– Strong enough to reach the thermocouple
– About 1-2 inches tall
If you notice changes in the flame’s color, size, or stability, it’s a sign that maintenance is needed.
Safety Concerns When Your Pilot Light Goes Out
While a pilot light going out is usually just an inconvenience, there are some safety issues to be aware of:
Gas Leaks
Modern furnaces and water heaters have safety features to prevent gas leaks when the pilot goes out. However, if these safety features fail, gas could potentially leak into your home.
If you smell gas (a rotten egg smell), leave your home immediately and call your gas company from a safe location. Don’t use phones, light switches, or anything that could create a spark while inside the house.
Carbon Monoxide Concerns
A pilot light that frequently goes out might indicate combustion problems. Poor combustion can lead to carbon monoxide production.
Always have working carbon monoxide detectors in your home, especially if you have gas appliances. Test them monthly and replace batteries twice a year.
Restarting Safety
When restarting a pilot light, always follow the manufacturer’s instructions. Typically, you’ll need to:
1. Turn the gas control valve to “Off”
2. Wait 5-10 minutes for any gas to clear
3. Turn the valve to “Pilot”
4. Hold down the reset button while lighting the pilot
5. Continue holding the reset button for 30-60 seconds
6. Turn the valve to “On”
If the pilot won’t stay lit after several attempts, stop trying and call a professional. Continuing to release gas while failing to light the pilot can be dangerous.
Frequently Asked Questions
How often should a pilot light go out?
A properly functioning pilot light should almost never go out on its own. If your pilot light goes out more than once a year without someone turning off the gas, there’s likely a problem that needs attention.
Does a pilot light use a lot of gas?
A standing pilot light typically uses a small amount of gas; it might be about $5-$10 worth per month. While not a huge expense, this adds up over time and is one reason newer systems use electronic ignition instead.
Can I leave my furnace with the pilot light out?
Yes, it’s safe to leave your furnace with the pilot light out. The safety systems will prevent gas flow. However, your heating system won’t work until the pilot is relit. During cold weather, this could lead to frozen pipes or an uncomfortable home.
Why does my pilot light go out when I release the button?
If the pilot goes out when you release the reset button, the thermocouple isn’t getting hot enough. This could be because:
– You didn’t hold the button long enough (try 60 seconds)
– The thermocouple is dirty or faulty
– The pilot flame isn’t reaching the thermocouple
– The gas pressure is too low
Is it dangerous if my pilot light keeps going out?
Modern gas appliances have safety features to prevent gas leaks when the pilot goes out. However, a pilot light that repeatedly goes out could indicate problems that might eventually become dangerous. It’s best to fix the issue rather than repeatedly relighting the pilot.
When to Call a Professional
While many pilot light problems can be fixed by homeowners, some situations require professional help:
Gas Smell or Leaks
If you smell gas or suspect a leak, leave your home immediately and call your gas company from outside. Don’t attempt any repairs yourself.
Persistent Problems
If you’ve tried the basic fixes and your pilot light keeps going out, it’s time to call a professional. There might be a more serious issue that requires expert diagnosis.
Older Systems
If your furnace or water heater is more than 15 years old, consider having a professional evaluate whether repair or replacement makes more sense. Older systems are more prone to pilot light and other problems.
Fix Your Pilot Light and Enjoy A Cozy Home
A pilot light that keeps going out is frustrating but usually fixable. By understanding the common causes and solutions, you can often solve the problem yourself and keep your home warm and comfortable.
Regular maintenance is the key to preventing pilot light problems. A little attention each year can save you from the inconvenience of a cold house in winter.
For persistent pilot light problems or if you’re uncomfortable working with gas appliances, don’t hesitate to call a professional. When it comes to your family’s safety and comfort, it’s always better to be cautious.
Need help with a pilot light that keeps going out or other heating system problems? Contact Julian Heat & Air for expert diagnosis and repair. Our experienced technicians can quickly identify the issue and get your system running reliably again. Book an appointment today to ensure your home stays warm and comfortable all season long.