Benjamin Franklin Plumbing shows you a photo of a water heater pilot light out.

22 Aug Water Heater Pilot Light Out?

Water Heater Pilot Light Troubles

There’s nothing more frustrating than a water heater pilot light that won’t stay lit. Not only does this prevent the furnace from running efficiently, but it prevents hot water from being readily available. Many factors contribute to why a pilot goes out and why it won’t stay lit. As soon as an understanding of why these factors are occurring, it can help future outages and save money. Here are some potential reasons why a water heater pilot light won’t stay lit.

Thermocouple Obstructions

The purpose of a thermocouple in a water heater is to help tell it if it’s on or off and most operate with them. The gas is shut off by the thermocouple as a precaution if it detects an unlit pilot. If there are obstructions or dirt, then it could cause a gas outage because there is an interruption in the electrical current. Cleaning the unit with a piece of sandpaper will resolve this problem. The gas must be turned off before any cleaning takes place and the unit must be cool.

Thermocouple Curving

A photo of a customer putting in a thermocouple into a water heater.

If there is bending or curving in the thermocouple, it’s no longer functional. The reason is that, if there’s a bend, it will move too far away from the pilot. When this occurs, the unit will believe the water heater pilot light isn’t lit. Once the unit is clean and no obstructions are present, carefully bend it back so it is back to where it can read the pilot light correctly.

Pay close attention to how close it is to the pilot light’s flame. Under most circumstances, it’s lightly touching the flame or just close enough to cause the device to experience heat. If there’s light wrapping around the sensor, then it’s close enough. Another good indicator is if the pilot light appears blue.

Thermocouple Damage

If it’s possible to rule out obstructions or any bending to the device, it may be that the device is broken. Under some circumstances, it’s possible for repairs to occur to remedy this problem. Otherwise, it will need replacing.

Before anything can occur, make sure the gas is not on and the device is cool to the touch. Upon doing so, remove the furnace cover and unscrew the unit. A multimeter test can determine if the device is no longer working by testing its voltage. If it reads below 20 MV, then it’s no longer operational.

Pilot Tube Dirty

Upon ruling each of these things out, another issue could be a dirty pilot tube. It’s possible for grime and dirt to build up, thus blocking proper gas flow. It’s simple to fix this issue, however. Once the gas is off and the pilot is cool, the tube can be cleaned out with a needle.

Simply remove anything that may be causing obstructions in the gas flow. Once this is complete, turn everything on to see if the water heater pilot light will stay lit. If the pilot light doesn’t stay lit, try repeating the needle process until the tube receives a thorough cleaning.

A photo of flexing tube, which could be why your water heater pilot light keeps going out.Flex Tubing Problems

If there are problems with the flex tubing, then the water heater pilot light will not stay lit. The purpose of this tubing is to ensure a steady stream of gas by connecting the unit to the gas controller. If kinks in the tubing occur, then improper operation will occur.

If it’s determined that this is the issue, then it’s possible that unkinking the tubing could solve the problem. However, under most circumstances, installation of new tubing is required. It’s uncommon for this problem to occur and should be addressed once everything else is ruled out.

Problems with Main Control Valve

It’s rare, but the pilot light could go out because of the main control valve. Before considering this option, rule out all other options. The main control valve will need replacement if this is the problem. The use of a multimeter can determine if the main control valve isn’t working properly and causing problems with the pilot light.

Final Thoughts

When a water heater pilot light doesn’t stay lit, it’s essential to troubleshoot many different scenarios before replacing parts. Not only does this prevent frustrations, but it also saves money. With a little time and patience, it’s possible to determine why these issues are occurring and solve the problem. For those who are still unsure about how to solve this problem, it might be helpful to call in the help of a professional.

Benjamin Franklin Plumbing Tyler serves the East Texas cities of Kilgore, Longview, Tyler, and Whitehouse with a team of certified plumbers. In addition to emergency plumbing repair, some of the plumbing services provided by the company include faucet repair, drain services, toilet repair, plumbing fixture installations, tub and shower installations, kitchen sink repair, faucet installation, water heater repair/replacement, and garbage disposal replacement. Call us today at (903) 730-6611 to schedule an appointment!



Book Now