When the pilot light in your gas water heater won't start or won't stay on for more than a few minutes, you won't have hot water in your home. The pilot light is designed to stay on all the time, so it's a definite sign of a malfunction if yours ever goes out. Thankfully, the problem is usually easy to remedy. If you're having problems with your pilot light, read on to find out how to diagnose and repair what's causing the issue.
Are You Resetting the Pilot Light Correctly?
The first step is to ensure you're resetting your pilot light correctly. It's not as simple as hitting the reset button on your water heater. While it's a good idea to read the owner's manual for your specific model, the procedure to reset the pilot light is typically the same for all gas water heaters.
First, you need to turn the gas completely off at the water heater's control valve. Afterward, set the control valve to the pilot setting and then depress it. Hit the reset switch on your water heater, and then (most importantly) keep the valve depressed for at least thirty seconds to continue delivering gas to the pilot light.
When the pilot light is burning, the flame heats up the thermocouple above it. The thermocouple is a thin metal tube that generates electrical current when it's heated, and this electrical current keeps the gas valve open. If you don't keep gas flowing to the pilot light for at least thirty seconds after igniting it, the thermocouple may not become hot enough to generate the required voltage.
Do You Notice a Spark When Resetting the Pilot Light?
If you don't notice a spark in your water heater's combustion chamber when you reset the pilot light, the igniter may have failed. Oil and carbon buildup on the igniter can cause it to work intermittently or not at all. The igniter is located adjacent to the thermocouple, and you can clean it with a microfiber cloth. Make sure not to touch it with your hands, since oil from your hands can cause the igniter to break.
Most of the time, cleaning carbon deposits and oil off of the igniter will fix it. If your igniter still isn't sparking when you reset your water heater, you'll need to replace it. Thankfully, this is an easy water heater repair to do. You simply remove the igniter's retaining screw and then replace it with a new one.
Does Your Pilot Light Have a Blue Flame?
The pilot light in your water heater should have a sizable blue flame while it's on. If the flame is small and yellow, then it's likely that it's not becoming hot enough to heat the thermocouple to the required temperature. This is most often caused by an obstruction in the pilot light's gas tube. After turning off gas to your water heater completely, you can remove the tube leading to your pilot light and clean it out using a wire brush. Once clogs are removed from the tube, the pilot light will become hot enough to heat up the thermocouple properly.
Has Your Thermocouple Failed?
If your water heater's pilot light still isn't staying lit after trying the above fixes, then it's likely that your thermocouple is broken. Corrosion and high heat can eventually cause the thermocouple to completely stop functioning. Thankfully, this is another easy water heater repair.
Again, you'll need to completely shut off the gas supply to your water heater. Remove the thermocouple and the wire connected to it from the combustion chamber, and then bring it to a plumbing supply store in order to find the proper replacement. If removing the thermocouple is difficult, you may want to remove the entire combustion chamber by removing the nuts that attach it to the water heater tank. This makes accessing and replacing the thermocouple easier. Once the thermocouple is replaced, then your pilot light should successfully stay lit.
Overall, fixing problems with the pilot light in a gas water heater is typically an easy task for a homeowner to do on their own. If replacing the thermocouple doesn't fix the problem, then it's time to call a professional water heater repair service. The problem with the pilot light may be due to a malfunction in the gas valve or with the water heater's control board, and both of these problems need to be repaired by a professional.