Top 10 Reasons Your Water Heater Pilot Light Keeps Going Out

Top 10 Reasons Your Water Heater Pilot Light Keeps Going Out

The Top 10 Reasons Your Water Heater Pilot Light Keeps Going Out

Are you tired of dealing with a water heater pilot light that keeps going out?

Please don’t feel like you’re alone in this situation; many homeowners experience periodic issues with their water heaters.

Thankfully, some simple fixes and maintenance tips can help prevent future pilot light outages or, better yet, stop them from happening periodically in the first place.

In this blog post, we’ll look at the top 10 reasons your water heater’s pilot light might be going out and discuss some solutions to help alleviate the issue for good.

So if you’re looking for the best advice and information on why your water heater pilot light won’t stay lit and how to remedy it, read on!

πŸ”₯ What Is A Pilot Light?

A pilot light is a small, constantly lit flame used to ignite gas appliances like furnaces and water heaters.

The pilot light acts as a spark to ignite the primary fuel source feeding the main burner, which is usually natural gas or propane, which powers the appliance.

Pilot lights are designed with safety in mind and typically have several safety features, including an ignition system that can be manually shut off if the flame goes out.

In addition, they often have sensors that will shut off the gas supply if there is a sudden drop in air pressure or temperature.

pilot light and thermocouple inside a water heater

πŸ”₯ How Does it Work?

The pilot light works by creating a small flame that can be ignited using matches or lighters.

This flame heats up a metal plate called a thermocouple, creating an electric current.

This current keeps the gas valve open so that more gas flows into the burner and ignites when ignited with the flame from the pilot light.

Once this primary fuel source has been ignited, it will typically stay on until manually turned off, either by pressing the button on the unit or flipping the switch near the appliance.

πŸ›‘ Safety Precautions When Working on a Water Heater

water heater repair

Following the safety precautions listed below when working on a water heater is essential for several reasons.

First, it prevents potential accidents and injuries that can occur when dealing with high levels of heat and gas.

Second, it helps ensure the connection is secure and will not lead to gas leaks or other hazards.

Finally, following these safety precautions may help extend your water heater’s life by avoiding unnecessary damage or wear caused by improper use.

  • Before beginning any work, turn off the power and gas shutoff valves.
  • Wear protective clothing such as gloves and goggles when working with hot water.
  • Make sure all connections are properly tightened to avoid gas leaks.
  • Use a step ladder when necessary to reach high places.
  • Unplug the water heater’s power cord before disconnecting the wiring.
  • Keep children and pets away from the area while you are working on the water heater.

πŸ’§ What Are The Reasons My Water Heater Pilot Light Keeps Going Out?

water heater pilot light repair

The reasons why your pilot light keeps going out are numerous.

Diagnosing and addressing pilot light problems adequately is essential so your water heater does not suffer from further damage or cause any safety risks.

Taking the time to investigate and address the root of the problem will help ensure that you can enjoy consistent hot water for years to come.

🧰 1. Dirty Pilot Tube

It’s not uncommon for water heaters to experience this issue.

But don’t worry- it’s usually caused by dirt or debris clogging the pilot tube, which supplies gas for the pilot light’s combustion process.

If the tube is partially blocked, it may not be able to provide enough gas for a sustained flame, so the pilot light’s flame will keep going out as a result.

Taking the time to unblock that tube can help avoid further issues and ensure your heater works as expected.

🧰 2. Lack of Combustible Air

A failing pilot light could be due to insufficient combustible air.

Your water heater needs plenty of fresh air to keep the pilot light flame burning properly.

Ensure there is nothing blocking airflow, such as clutter or other debris.

Maintain a clean area around the hot water heater for best results.

🧰 3. Pilot Flame is Too Small

The pilot light in a gas water heater may be too small due to low gas pressure.

Ask your gas company if they are providing the right amount of fuel – it could be that the problem lies within the water heater itself.

A clogged pilot light tube could also contribute, caused by dirt getting into the system from the gas line.

Installing a dirt trap can help alleviate this issue though this should only be done by a qualified professional.

Also, by consulting the manufacturer’s instructions, check that you have the correct sized burner orifice.

Finally, remember that the flame should always be blue, and ensure the storage tank is full before ignition.

🧰 4. Pilot Flame is Too Large

A pilot light that is too large or out of control could result from high gas pressure, which can be due to a problem on the part of the gas company. If you suspect this is the problem, call your local gas company.

Additionally, check that you have the right-sized burner orifice.

Ensuring you have the correct-sized burner orifice for your water heater for optimal performance is vital.

If the pilot orifice’ size is too large, it can cause the pilot flame to be too high and unstable. This decreases the lifespan of your water heater and can also be a safety hazard.

Furthermore, having an incorrect-sized burner orifice will result in lower efficiency and higher fuel bills. Thus, ensuring the right-sized burner orifice is essential for protecting your wallet and safety.

🧰 5. A Dirty Thermocouple

The thermocouple is your water heater’s brain, controlling the gas flow if it senses the pilot light has gone out.

When the pilot light is lit, it creates an electric current, which triggers the gas valve to close if the flame goes off. A layer of dirt and grime can prevent this electric current from reaching the thermocouple, leaving you without hot water on a cold morning.

To avoid this issue, regularly cleaning off any dirt and grime from your faulty thermocouple is essential. Taking a piece of sandpaper and carefully scrubbing away any residue should ensure your water heater keeps pumping out hot water.

🧰 6. A Kinked Thermocouple

Cleaning your thermocouple is only the first step. The following important task is to check its position and whether it has become kinked. The thermocouple must be relatively close to the pilot light to receive heat and generate an electric current.

If it’s too far away, no signal will be produced, and the gas valve will be closed, leading to a lack of hot water. To ensure this doesn’t happen, you should manually adjust and straighten the thermocouple so it slightly touches the blue flame of the pilot light.

🧰 7. A Broken Thermocouple

After cleaning and positioning your thermocouple, if you still find that the pilot light keeps going out, it could be that the thermocouple is broken.

To confirm this, run a diagnostic test with a multimeter to measure the voltage supplied by the thermocouple.

The thermocouple millivolt reading should be approximately 30 millivolts (mV) with an error rate of plus or minus 5 mV.

If your thermocouple is putting out less than 25 mV, we recommend replacing it.

However, if the reading is close to but not at 30mV, you can try moving the device closer to the pilot light before giving up on it completely.

🧰 8. Flex Tube Issues

The flex tube is a long tube that connects the gas controller to the gas burner where the pilot light and thermocouple are located.

If there are any kinks or visible damage to this piece, it could block the gas flow to the burner. If you don’t detect any issues with your thermocouple, you should straighten out any kinks on your flex tube and look for signs of gas leakage since this could be another reason why your water heater pilot light won’t stay lit.

🧰 9. A Faulty Main Control Valve

Checking the pilot light, thermocouple, and flex tubes should be your first step if your water pilot keeps going out.

However, please don’t rule out a problem with the main gas control valve unit, as it may be the culprit.

This component is a safety device responsible for regulating gas supply and water pressure.

If a fault occurs here, it can cause an unexpected closure of the gas valve and a weak flickering flame.

Here are some possible signs of a faulty main control gas valve:

  • A pilot button that won’t pop up after pressing it
  • A faulty control knob
  • Hot water exceeding the specified temperature range

Unfortunately, there is no way to fix this part, so manufacturers advise replacing it to avoid potential recurring costs and damages caused by other components.

🧰 10. Poor Electrical Wiring

This is usually a problem associated with electric water heaters.

If your water heater suddenly shuts down, this could indicate an electrical issue and should not be ignored.

Switch off the device immediately and contact a technician for help.

Don’t attempt to fix the wiring yourself unless you’re a qualified electrician.

🚿 Final Thoughts

Phyxter Approved Logo on Service Truck

Fortunately, if you’ve been dealing with the frustration of a constantly failing water heater, you now understand what might happen better.

Out of all the potential causes we discussed, one constant remains.

Be sure to call a professional plumber if any of them are beyond your ability to fix.

After all, it’s better to be safe than sorry regarding plumbing repairs.

Even though this article may have helped shed some light on the matter for you and provided tips on fixing your water heater in specific scenarios, understand that there are often more complex issues beyond what can be quickly solved.

So don’t hesitate to call a trusted local plumber for assistance.

If you need further advice or resources on these topics, remember our blog is an ever-expanding repository of homeowner plumbing-related knowledge!

Related Reading: Hot Water Not Working But Cold Is? Here’s What You Need to Know

Russell Jones

Russell, a native Australian and VP of Operations at Phyxter Home Services, is also part-owner of Vernon Air Conditioning, Plumbing, and Electrical Services. When he's not busy with work projects and renovations, Russell enjoys putting his vast knowledge of home improvement to good use by sharing his tips and tricks.

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