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Water Heater Pilot Light Won’t Stay Lit – 10 Causes & Solutions

Fact checked by Stephen Conklin

water heater pilot light won't stay lit

To tell why your water heater pilot light won’t stay lit, you’ll have to examine its component. Typically, this issue stems from problems with the pilot tube, flex tube, thermocouple gas control valve, igniter, solenoid, or other gas water heater pilot light components.

Please keep reading to learn about these reasons for the pilot light not staying lit and help you decide whether to troubleshoot and fix the problems yourself or hire a professional.

Table of Contents

10 Reasons the Pilot Light Won’t Stay Lit (and How to Troubleshoot/Fix Them!)

We gathered sufficient information to categorize pilot light-associated issues into eleven. You’ll be amazed at how “benign” these reasons might seem, yet they are instrumental in a pilot light that keeps going out.

1. Gas supply issues


You might laugh, but gas supply is one of the most often overlooked reasons for a pilot light that won’t light or stay lit. After all, the pilot light needs gas to light up and stay lit.

Troubleshooting and Fix

  • Check the gas supply’s main valve and ensure it’s “open.” Twist the valve’s handle to align it with the gas pipe.
  • Assess the gas control valve knob on your water heater. Ensure it’s in the right position, allowing you to depress the knob during activation. I should have no issues lighting the pilot light and keeping it lit when I release the knob.
  • Check if your propane gas tank is empty by looking at its gauge. If there’s no propane gauge, disconnect the gas tank and pour warm water onto it. Then, touch the tank—it should feel cool wherever there is propane.
  • You can also assess the natural gas meter and evaluate whether it’s still running.

2. Blocked pilot tube


If the pilot light won’t stay lit on water heater, it could be due to debris, dirt, and other particles blocking the pilot tube. This small tube delivers gas to the pilot light. Pipe blockage translates to zero or insufficient gas reaching the pilot light, causing it not to light up.

Troubleshooting and Fix

  • Get a needle or a thin wire and insert it through the pilot tube. This action will help dislodge any obstructions.
  • After “cleaning,” try to reignite the pilot light. The device should produce a nice blue flame. If not, you can keep removing the blockage or just get a new pilot tube.

3. Issues with the Piezoelectric igniter


Modern gas water heaters feature a “spark igniter” to eliminate the need for manually igniting the pilot light with a stick lighter or matchstick. Unfortunately, this component is not immune to problems.

Troubleshooting and Fix

  • Grab a can of compressed air and blitz the piezoelectric igniter to remove dust, dirt, and other debris. Press the igniter to see if the pilot light ignites and stays lit.
  • Check the piezoelectric igniter if the pilot light is not lighting Assess the grounding wire, ensuring it’s in the correct location. Otherwise, you can reposition the cable to the water heater’s frame so the igniter gets voltage.
  • Assess the spark igniter’s spark rod and pilot light termination for signs of rust or corrosion. You can try to remove the buildup with steel wool and check if the pilot light ignites and stays lit.
  • If that doesn’t solve the problem, you might want to buy a replacement piezoelectric igniter. This is especially true if the igniter doesn’t glow, despite getting voltage.

We recommend getting a component specific to your water heater. For example, the Rheem Sp14410 is perfect for a Rheem water heater.

4. Flex tube kink


The flex tube conveys gas from the main supply line to the water heater’s gas controller. Kinking can interrupt or reduce gas flow.

Troubleshooting and Fix

  • Follow the flexible tubing from the water heater’s gas controller to the main gas supply line.
  • Ensure the tubing has no kinks. Straighten the flexible piping to facilitate more efficient gas flow.

5. Thermocouple rod is not in its correct position

The thermocouple senses heat from the pilot light, allowing it to produce electricity to keep the gas valve supplying the pilot light open. Hence, if the pilot lights only stay lit for a few minutes, there’s a good chance the thermocouple is the problem.

Troubleshooting and Fix

  • Assess the thermocouple rod’s position, ensuring it’s next to the pilot light’s flame. Otherwise, the device cannot sense the flame-generated heat and keep the gas valve open.
  • You can reposition the thermocouple rod and restart the pilot light.

6. Dirty thermocouple rod


Sometimes the thermocouple is in its correct position, yet it still doesn’t “sense” heat from the flame. Similar to how a clogged-up pilot tube can keep the pilot light from lighting, a thermocouple rod can cause you headaches as well.

Troubleshooting and Fix

  • Remove the cool thermocouple from its platform.
  • Clean the thermocouple rod with steel wool (without soap).
  • Replace the thermocouple into its bracket and reignite the pilot light.

7. A defective or worn-out thermocouple

A more sinister issue might be causing your pilot light not to stay lit if the thermocouple rod is neither dirty nor malpositioned. You might need a new thermocouple installed in your water heater.

Troubleshooting and Fix

  • Get a multitester to check the thermocouple’s functioning.
    • When the thermocouple is cool to the touch, remove it.
    • Set your multimeter to the ohms function.
    • Touch the two multimeter probes to the thermocouple’s top end and the metal’s tubing side.
    • Turn on the lighter.
    • See if the result is between 25 and 35. If not, the thermocouple is broken.
  • Replace the thermocouple if defective. However, we must reiterate the need to test the pilot light after replacing thermocouple.

8. The pilot tube’s end is not in its correct position


The ideal setup is for the thermocouple to stay next to the pilot light’s flame to sense heat. After troubleshooting the thermocouple and the issue of the pilot light not staying lit persists, it could be a malpositioned or bent pilot tube terminus.

Troubleshooting and Fix

  • Open the pilot light access panel and assess the pilot tube terminus’s position.
  • If it’s bent, you have two choices. You can either replace the deformed component or remove the old pilot light assembly and install a new one.

9. The pilot head doesn’t receive adequate gas pressure

So, the pilot tube terminus isn’t bent, but your pilot light still won’t lit. The situation might be due to low gas pressure exiting the pilot head. Lower-than-normal gas pressure can prevent the thermocouple from sensing flame-generated heat.

Troubleshooting and Fix

  • Access the pilot light assembly and assess the pilot tube’s opening. Check for obstructions or any sign of clogging.
  • Try to remove the blockage by forcing compressed air.
  • Replace the pilot tube if this doesn’t work.

10. Defective solenoid


Although this issue is uncommon, you will feel more confident learning about it. The solenoid is an integral part of the gas valve, allowing it to stay open and supply gas to the pilot light and burner. A bad solenoid prevents this action from happening.

Troubleshooting and Fix

  • Ascertain there’s nothing wrong with the thermocouple, flex tube, gas supply, pilot tube, and piezoelectric igniter.
  • Replace the gas control valve or hire a professional to complete the task if your water heater is near its end.
  • Alternatively, you can ask a professional to repair the broken solenoid.

How to Determine That I Have These Issues

Determining water heater pilot light issues requires understanding how this device works, including its components and their respective functions.

You can read your water heater’s User Manual or Owner’s Guide for details on how to inspect these technologies and their operation. Doing so will make you more confident in troubleshooting and diagnosing why your pilot light doesn’t stay lit.

Alternatively, a professional can help you determine pilot light issues. Moreover, the technician can offer a more appropriate solution to the identified problem.

Safety Considerations


Many novice water heater owners ask whether working with pilot lights is safe. Is it dangerous? Should they leave professionals to do it? What safety considerations should homeowners remember? Below are a few key points:

  • Always turn off the gas supply valve if you smell “rotten egg” when the pilot light isn’t lit. Open the door to let the gas disperse, but you should only do so if you’re sure the opening doors won’t cause any electric spark.
  • Remove objects that can easily catch fire, including combustible chemicals, flammable liquids, paper, cardboard, and similar items.
  • Wait three to five minutes before relighting the pilot light to avoid untoward incidents.
  • Read the water heater manufacturer’s installation, operation, and maintenance instructions.

When to Call a Professional


Although the troubleshooting guide and solutions we offered in this article are straightforward to execute, most folks are more confident when a professional handles such issues.

The pilot light might seem like a small device, but it requires expertise to troubleshoot, diagnose, and fix it. If resetting the pilot light doesn’t address the problem of the light not staying lit, a professional can help zero in on the most likely culprit.

Lack of confidence and insufficient water heater pilot light knowledge warrant calling a professional. After all, you don’t want to create more problems, especially after flood or other weather disturbances.

Tips to Prevent Problems of Water Heater Pilot Light


Pilot light issues don’t randomly occur. Most are preventable. Here are some tips to keep your pilot light functioning properly.

  • Observe a periodic and frequent assessment, cleaning, and maintenance of the pilot light assembly and other critical water heater components.
  • Have a professional service your water heater at least once a year or according to the manufacturer’s recommendations.
  • Ensure adequate gas supply to the pilot while checking the integrity of associated elements.

When Should I Replace Water Heater Pilot Light

You must consider replacing your water heater pilot light if it doesn’t light anymore or stay lit. You can troubleshoot your appliance using the tricks we outlined in this article. Note that replacement is unnecessary in a dirty pilot tube.

It is worth remembering that a pilot light ignites the water heater’s burner. Hence, a defective or failing pilot light will impact the appliance’s water heating capabilities. There’s a good chance replacing the pilot light assembly is necessary if you’re no longer receiving sufficient hot water.


At least ten reasons can help explain why the water heater pilot light won’t stay lit. After careful analysis, we can categorize these issues into problems associated with the water heater’s pilot tube, thermocouple, and gas supply (including associated components and functions).

Although troubleshooting these issues seems straightforward, we recommend having a professional assess your water heater. There’s a good chance your pilot light isn’t the only concern, especially if your appliance is nearing its end.

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