Why Your Water Heater Pilot Light Isn't Working and Troubleshooting Tips (2024)

One of the most common problems that you will face with your gas water heater is a faulty pilot light. The water heater pilot light needs to stay lit for a number of reasons. Not only does it ignite the gas inside your heater, but it also helps to maintain the internal temperature of your water heater, which cools over time.

Igniting the pilot light is the first step you take to turning on the water heater. If this isn’t working, then you know there will be a problem with the whole unit. As this is a fairly common problem among gas water heaters, it is also pretty easy to fix.

Take a look at our guide below to troubleshooting and fixing your water heater pilot light.

Table of Contents

Lighting a Gas Water Heater Pilot Light

Before starting to worry about your broken pilot flame, you will need to make sure that you are igniting it properly first. This is the initial step for any pilot light troubleshooting.

You get two different types of water heater igniters. The older kind requires you to manually light the flame with a match or lighter, while the newer models utilize a spark igniter through the push of a button. The same basic rules for lighting the pilot flame applies for each model.

Igniting the Pilot Light

  • Make sure that the pilot control knob has been turned off before starting the process
  • Once the system has been turned off, you will need to wait a while for everything to cool down. Make sure that the burner compartment and thermocouple have been properly cooled down. Giving it time will also make sure that any excess gas from the pilot disappears.
  • Once cooled down, turn the pilot control knob to light.
  • If you have one of the older, manual models, this would be the time to strike a match or get your lighter ready.
  • Now you will need to press the pilot knob down on the light setting and hold it there for a while. This will release the gas to the pilot flame. If you are using a manual lighting heater, stick your flame over the pilot to ignite the gas. If you have a newer model, this is when you will need to press the ignite button to spark the gas. Once lit you will need to hold the button down for a while to ensure that it keeps burning.
  • Once the pilot is burning well, release the knob and turn it to the ‘on’ setting.
  • Now the water heater pilot light should be burning smoothly. If the light starts to flicker, or goes out, then it would be time to troubleshoot the problem.

While this guide applies to basically all water heaters, be sure to check the instructions of your specific unit first. Different igniting systems may vary slightly. It is also important to make sure that you don’t smell any gas leak in the air when you ignite the water heater pilot light.

7 Reasons Why the Water Heater Pilot Light May Not Be Working

We see faulty pilot lights pretty often, so there is no cause for major concern if this is the case. Here are seven of the most common reasons why your water heater pilot light might not be working, and how you can fix it.

Clean the Air Vents

Underneath the burner, at the bottom of the tank, or on the sides of the pilot light there should be air vents. Firstly, make sure that these vents are clean in order for the burner to run smoothly. If these are blocked up, there will be a lack of oxygen which can affect your flame. This is the first thing to notice.

Interrupted Gas Flow

This is one of the most common reasons why your pilot light may not be working, and it is something that can happen in old and brand new models. Luckily, this one is super quick and easy to fix by yourself.

Your water heater will have a flex tube that connects to the gas controller. Sometimes this tube may become kinked, restricting the flow of gas. As these tubes are found externally, this can be an easy issue to figure out.

Simply straighten out the kink in your flex tube and you should be good to go! If the problem continues though, perhaps you should have a look at the thermocouple.

Dirty Pilot Tube

This is something that could commonly occur in older water heaters that have seen plenty of use. If your pilot light won’t ignite or flicker at all, then there is a good chance that a dirty pilot tube is the cause of it.

Check your pilot tube to see if there is any dirt in it. Sometimes this little tube will get blocked off by some kind of unwanted debris, restricting the flow of gas. If this is the case, then an easy fix is in order.

All you need to do is take a needle or thin piece of wire, and run it through the pilot tube until it has been cleared out. Try to light the flame again to see if you have been successful in unblocking the tube.

Bent Sensor

This is another pretty simple problem with an easy fix. Have a look at your thermocouple – there should be a sensor at the end of it that just touches against the pilot flame when lit. Sometimes this sensor can bend away from the flame, causing an issue with the heater.

All you need to do is bend this little sensor back in place so that it will lightly touch the flame. Problem solved.

Broken Thermocouple

As one of the most important parts of your water heater – if it is broken or damaged, your pilot light won’t work. There are a few ways in which it may be damaged, some more serious than others.

The best way to check this out is by taking a reading with a multimeter. If this reading is above 20MV then it should be fine. Anything below this though, and you will know that the part is damaged. This will then require replacing with a new one.

Dirty Thermocouple

Sometimes your thermocouple can give you problems that are easy to fix. This is commonly found through an obstruction in the device. This little gadget is designed to monitor whether the pilot light is on or not through an electric signal. If the thermocouple thinks that the pilot is out, it will shut off the gas supply.

This often happens if there is some kind of dirt or debris getting in the way of this signal. Simply remove the it from your water heater, and gently rub and clean it down with a cloth or piece of fine sandpaper. This should remove any dirt blocking the signal.

Damaged Control Valve

While the issues mentioned above are all fairly easy to figure out and fix, a damaged control valve can be a pretty serious problem. If your pilot light isn’t working, be sure to look into all of the above issues first before jumping to the control valve.

If you can’t seem to find the problem, then chances are it’s a faulty control valve. Unfortunately, this can be quite an expensive issue to repair. It is not an easy job either. The only way to fix this is through replacing the control valve – something that is best done by a professional.

Replacing the Thermocouple

Out of all of the problems that could occur with your water heater pilot light, a broken one of the most common. Luckily, replacing these parts is a job that can be done at home pretty easily – especially if you have an older manual water heater. If you have a sealed burner compartment though, this could get a bit more tricky.

To replace one, start by turning the gas supply completely off. Shut off the supply valve, and turn the pilot control knob to off.

The thermocouple will be fastened to a bracket. Use a wrench to loosen the screws and take the device off of the bracket. Reach into the burner compartment and pull it out completely.

Take your new one and bend the wire on it so that it matches the position of the old one. Reinsert and screw this new device down onto the bracket. Make sure that the tip of it will just touch the pilot flame.

Then all you need to do is connect the outer end to the gas control valve and tighten this firmly. Now you can relight your pilot flame.

Conclusion

If your water heater isn’t working properly, heating up, igniting, or cooling down, then the pilot light should be the first place to look. There are a number of reasons why your water heater pilot light may not be working – most of them are easy enough to troubleshoot and fix at home.

Be sure to check out all of the possible options, and see what you can do to get the pilot burning smoothly again. One of the most common issues will come from the thermocouple, something that can be replaced pretty easily.

It is important to remember that if you are confused about what the cause might be, or are unsure how to fix it, rather called an experienced water heater maintenance professional to take on the job.

We hope this has answered your questions as to why your water heater pilot light isn’t working. For more maintenance tips on your water heater appliance, check out the dedicated section in the link above.

You Might Also Like:

Water Heater Explosion: Causes, Warning Signs, Prevention Tips

Consider Water Heater Installation Costs

Why Your Water Heater Pilot Light Isn't Working and Troubleshooting Tips (2024)

FAQs

Why Your Water Heater Pilot Light Isn't Working and Troubleshooting Tips? ›

Pilot Light Keeps Going Out

What would cause water heater pilot not to light? ›

In many cases, the reason that you can't get your pilot light to ignite is that the pilot tube is clogged. This is a small metal tube that supplies the gas needed to ignite the pilot and keep it lit. The pilot tube often becomes clogged with debris, and this will prevent gas from flowing to the pilot light.

What do I do if my pilot light won't light? ›

How to Fix Your Pilot Light
  1. Find your gas valve. ...
  2. You need to turn the valve to the off position for at least three minutes.
  3. Once you have had the valve at off for a few minutes, switch it over to pilot setting.
  4. You will need a match that is lit. ...
  5. Set the pilot valve to the on position.

How do I know if my thermocouple is bad? ›

If the pilot flame ignites but goes out after you release the gas control knob, the cause may be a dirty or defective thermocouple. If the gas is on but the flame will not ignite at all, a pilot tube obstruction is the most likely issue. Remove the pilot tube from the gas valve and spray compressed air to clear it.

How do I know if my thermocouple is bad on my water heater? ›

Recognizing a Bad Thermocouple

A telltale sign of a bad thermocouple is when your water heater's pilot light refuses to stay lit. If the pilot light goes out or won't stay lit, the thermocouple is not transmitting the right signal to the control valve.

How do you clean a thermocouple? ›

Yes, you can clean a thermocouple, but the task must be done with a light touch. Remove the thermocouple from the process assembly, using a steel wool or emery cloth, lightly clean the tip removing any build up. Cleaning a thermocouple is not a fix for an issue, such as inaccurate readings.

What would cause a pilot light to keep going out? ›

When there is a buildup of dirt in the pilot light port, it can prevent the flame from properly engulfing the thermocouple. In turn, the safety mechanism is triggered, turning off the gas. This is a very common culprit resulting in why your pilot light keeps going out.

How much does it cost to replace a thermocouple? ›

If your thermocouple goes bad, there is only one thing to do: Replace it. If you hire a professional plumber to do this, it may cost up to $200 total. This is another repair you may wish to attempt on your own. The part itself should only cost $20 or $30.

How do you make a pilot light work? ›

If it doesn't have the button, or the button fails, press the regulator valve and hold a grill lighter or long match to the pilot light valve until the pilot ignites. Hold the button down for up to a minute to ensure that the light stays lit.

Will pilot stay lit if thermocouple is bad? ›

A thermocouple is a function on your water heater that senses the heat on the pilot light and allows gas to flow to the burner. A bad thermocouple will shut off gas to both the pilot and the burner, which is when people notice that the water heater pilot light is out.

Can I replace a thermocouple myself? ›

It's easy to replace and a new one costs $5 to $10. Rather than trying to unfasten the thermocouple inside the water heater's burning chamber, it's easier to remove the whole burner and thermocouple assembly.

How often should a thermocouple be cleaned? ›

As for how often the thermocouple should be cleaned, we recommend roughly once every six months or so.

Should I clean or replace thermocouple on water heater? ›

To determine if your thermocouple only needs a good cleaning or requires replacement, it will come down to how often your pilot light is going out. If you're experiencing pilot light outages every few days or have a water heater that is over 10 years old, you'll do better by replacing the thermocouple.

What happens when a thermocouple goes bad on a water heater? ›

The thermocouple is usually placed very close to the pilot light and may even be a part of the same component, depending on the nature of your water heater. Normally when the thermocouple malfunctions or isn't working, it simply shuts off the gas to your heater.

Why won t my pilot light stay lit when I release the knob? ›

If you try to relight a pilot light and the thermocouple is bent in a way that causes it to not make contact with the pilot light, the flame will instantly go out when you release the pilot control knob since the probe won't detect the heat from the flame.

How much does it cost to replace a thermocouple on a water heater? ›

Thermocouple – $20 to $150

The thermocouple is an apparatus that senses whether the pilot light is lit and triggers the gas control valve. Repairs typically cost about $150 to have it done professionally, though a new thermocouple itself only costs about $20 on average.

How do I determine if electronic ignition is bad on my water heater? ›

To determine if the igniter is defective, first make sure the igniter is getting voltage. If the igniter is getting voltage, but it doesn't glow, this indicates that the igniter is defective and should be replaced.

Top Articles
Latest Posts
Article information

Author: Gov. Deandrea McKenzie

Last Updated:

Views: 5916

Rating: 4.6 / 5 (66 voted)

Reviews: 81% of readers found this page helpful

Author information

Name: Gov. Deandrea McKenzie

Birthday: 2001-01-17

Address: Suite 769 2454 Marsha Coves, Debbieton, MS 95002

Phone: +813077629322

Job: Real-Estate Executive

Hobby: Archery, Metal detecting, Kitesurfing, Genealogy, Kitesurfing, Calligraphy, Roller skating

Introduction: My name is Gov. Deandrea McKenzie, I am a spotless, clean, glamorous, sparkling, adventurous, nice, brainy person who loves writing and wants to share my knowledge and understanding with you.