Water Heater Pilot Goes Out After A Few Hours | Causes & Troubleshooting Tips

A water heater pilot light is a small flame used to ignite the gas burner in a gas water heater. The pilot light is essential for properly functioning the water heater, providing the heat needed to warm the water.

However, it is not uncommon for the pilot light to go out after a few hours of use. Various factors, such as a malfunctioning thermocouple, a clogged gas line, or a draft in the room, can cause this.

If the pilot light goes out, it will be necessary to relight it to continue using the water heater. This article will discuss why a water heater pilot light might go out and what steps you can take to fix the problem.

Your water heater’s pilot light will most likely go out because of a damaged, bent, or dirty thermocouple.

What’s A Pilot Light?

An electric pilot light is a device that continuously burns a flame. Ignition of the burner takes place through this part. Exactly how?

When your appliance is turned on, gas is released from the main burner, and a pilot light flame ignites it to produce heat.

The heat that warms your main burner is also used to heat the air or water inside your appliance, which is distributed as needed throughout your home or business.

What Is A Thermocouple?

Temperature measurement is its simple definition. In addition to regulating gas flow inside your water heater or furnace, it controls the temperature. It has two wires. The first one is near the thermostat, and the second sits near the pilot light’s flame.

In response to rising temperatures, the thermocouple sends an electric signal that activates the gas valve and permits combustion. Sensing a temperature drop, the thermocouple closes the gas valve if the pilot light goes out.

In most cases, a faulty thermocouple causes your pilot light to malfunction. It is normal for your water heater to collect dust, dirt, and other debris over time. It is possible for your thermocouple to malfunction because of buildup.

You can solve this problem simply by letting it cool down and brushing off the dirt or debris. You might have a bending thermocouple.

Gas valves are controlled by the end that sits near the pilot light flame, which is what communicates with them. The gas valve does not register heat if bent away from the flame.

You can bend your water heater back once it has cooled down. Don’t try to repair your issue if you don’t know what to do. Call us, and one of our professional technicians will assist you.

Despite not being bent or dirty or having to troubleshoot both issues, you may still have a defective thermocouple.

Reasons Your Water Heater Pilot Light Keeps Going Out

Reasons Your Water Heater Pilot Light Keeps Going Out

The start of a chilly day is made worse by a chilly shower. It may have just occurred to you that the pilot light keeps going out. So, why does your water pilot light keep going out?

1. Poor Electrical Wiring

A water heater with an electric element usually has this problem. This is why you should always hire a professional to install your water heater. Water heaters that suddenly stop working may have faulty electrical systems.

You should immediately turn off your water heater and contact a technician. Be careful not to damage the wiring.

2. A Faulty Main Control Valve

Possibly the rare problem you will ever encounter.

Before tampering with this part, it’s recommended that you check the pilot tube, thermocouple, and flex tube first. In most cases, the Main Control Valve Unit does not crash.

Nevertheless, don’t rule out this possibility; your water pilot may malfunction for various reasons. To regulate the heater’s gas and water pressure, the Main Control Valve is responsible. An electric water heater can’t function without it.

A small amount of gas is first supplied to the pilot light to begin the process. If the gas is lit, the main valve will fully open, allowing a steady supply of gas to flow.

Whenever there is a problem with the main control valve, the gas valve will close unexpectedly, cutting off the gas supply and creating a flickering flame.

There are several signs that indicate a faulty main control valve, including:

  • When pressed, a faulty pilot button does not appear
  • The control knob is faulty

When the water is extremely hot, it exceeds the specified temperature range. Changing the main control valve is not an option if it is faulty. It is strongly advised against attempting to fix this technician, despite claims that they can do so.

We advise you to replace the part to prevent recurring costs and damage to other parts of your water heater.

3. Flex Tube Issues

Flexible tubes connect the gas controller with the burner, which contains the pilot light and thermocouple, among other pieces. Damaged or clogged flex tubes will prevent gas from being supplied to the burner for combustion.

It is, fortunately, rare for flex tube faults to occur as frequently as thermocouple issues do. Before paying attention to the flex tube, ensure your thermocouple is in great shape.

The Solution: Straighten every kink in the flex tube. Check for visible signs of damage that might cause gas leaks as well.

In addition to reducing the gas supply to the burner, leaks will reduce gas pressure. You might be experiencing frequent outages or flickers because of it.

4. A Broken Thermocouple

It’s been a while since you had a water pilot issue, but you’ve cleaned and straightened your thermocouple. Your thermocouple might be broken now, so you should accept that fact.

If you don’t think your thermocouple is working, use a multimeter to diagnose it. When your thermocouple provides less than 20 MV, it probably needs to be replaced as it is broken.

The Solution: If the multimeter reading is close to, but not at 20MV, you can move the thermocouple close to the pilot light. You have no choice but to replace the damaged part if the reading is well below 20 MV.

5. A Kinked Thermocouple

You should check the thermocouple’s position after cleaning it. Be sure to check if it’s slightly bent as well.

The thermocouple must be on the same side of the pilot light as the gas valve to receive heat and operate.

The heat won’t be received if the distance is too great, and an electric current can’t be produced. As a result of the thermocouple detecting that the pilot light is out, the valve will be closed, and the gas will be shut off.

The solution:

  • Give your heater a quick turn-off.
  • Disconnect the gas supply.
  • Wait until the thermocouple cools down.

If you need to bend or straighten the thermocouple back to its original position, you will need to do so manually. There must be enough distance between it and the pilot light to allow a slight touch or to wrap around the pilot light’s flame.

6. A Dirty Thermocouple

Water heaters contain a thermocouple that acts as their brain. When the pilot light has gone out, the gas valve closes automatically. A pilot light produces an electric current which triggers the thermocouple.

The device prevents gas leaks by acting as a safety device. As a result, your water pilot may keep going out because of a dirty thermocouple.

Dirt and grime can prevent electric current from reaching a thermocouple. The pilot light will go out due to cutting off the gas supply. An early Monday morning without hot water.

The solution: Once again, you’ll need to clean. You must first turn off the main gas supply valve and allow the thermocouple to cool. Get a new sandpaper and scrub off all the dirt and grime.

7. An Unclean Pilot Tube

Most water heaters suffer from this problem. It’s nothing to worry about; your heater is in good working order. There is just dirt buildup.

Gas is supplied to the pilot tube for combustion by the pilot light. The tube must not be clogged with dirt or debris to prevent the flame from going out.

Occasionally, the tube can become partially clogged and provide very little gas to the pilot light- no wonder it keeps going out.

The Solution:

  1. Give the area a thorough cleaning.
  2. Gently unclog the tube with a slender needle.
  3. Make sure the passage is clean until it is open.

It is important to be patient. There will be times when you’ll need to clean pilot tubes several times. Reconnect your water heater and turn it on as soon as you’re done. You should see a steady blue flame.

Is It Dangerous If The Pilot Light Goes Out On Water Heater?

The same thing has happened to all of us. In the middle of taking a warm shower and getting ready for the day, the water suddenly turns ice cold. You don’t want to have that experience in the morning because it’s unpleasant and can ruin your day.

Often, the problem’s cause is the water heater’s pilot light. A water heater pilot light that goes out can make for a cold experience, even if it is not dangerous.

Whenever your pilot light goes out, you must go to the water heater and light it up again. This will allow you to use the water again once it has warmed up.

There’s a possibility that when a pilot flame goes out, the gas valve supplying fuel for it may still be pumping gas.

The pilot can be relit or relight itself after this, which could result in an explosion. The incidence of this disease has decreased in recent years, however.

It is expected that all furnaces made within the next 20 years or so will be equipped with a failsafe electrical shut-off valve. Gas flow is automatically shut off following the extinguishing of the pilot, preventing excessive gas buildup.

Final Words

You must call in the big guns (technicians) if your pilot light keeps going out despite your attempts. There’s no denying that technicians cost a bit, but at least you’ll feel more confident in the results of the repairs.

Furthermore, we all know that electricity and gas can be very dangerous. The safety of you and your family is paramount.

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