The pilot light is a critical piece of your water heater, and if it is not staying lit, there are reasons behind it besides a ghost haunting your house and blowing it out (If you are looking for answers on this, I will consult your neighborhood ghostbusters).
A few reasons why a water heater pilot light goes out are due to a dirty pilot tube, a kink in the flex tube, a bent or damaged obstruction in the thermocouple, a faulty burner or electrical system, or a bad main control board.
Here I will discuss these common water heater pilot light issues and how to fix them yourself. If you are unable to fix it yourself, you may want to consider calling a professional to take a look.
Reasons Behind the Pilot Light Not Staying Lit
The reasons a pilot light will not stay lit are more than you may realize. Here are the different reasons behind this issue and how to fix it:
Dirty Pilot Tube
Dirt and buildup are common reasons for your water heater to stop working, and when it comes to pilot light issues, this sediment clogging can also be its cause.
The pilot tube allows gas to flow through and ignite the flame. If this is clogged, gas cannot flow through it efficiently or effectively. The pilot light may not stay lit because of this or if it does light at all, it may produce a weak light that goes in and out.
Beware: if you see an orange or yellow flame instead of a blue flame, leave your house immediately and call the gas company, as this could mean that your pilot light is leaking carbon monoxide into your house.
Kink in Flex Tube
Another reason your pilot light is not operating as it should be is the flex tube. Similar to the situation above, a flex tube with bends or kinks can restrict gas flow. When flow is restricted or closed off, gas cannot make its way through to light the pilot light.
To fix: Turn off the gas valve and allow 10 minutes for the gas to disperse. Then, straighten out the flex tube where kinks and dents occur and smooth it out as best as possible. If your pilot light still doesn’t light, you may need to replace it. Do check other potential causes before replacement, though.
Obstruction in Thermocouple
The thermocouple is a tiny probe that signals the gas valve to open whenever the pilot light is on. When this device is compromised or faulty, it will prevent the pilot light from staying lit.
Any obstruction to the thermocouple can prevent it from operating. When dirt and particles settle and build on the thermocouple, it can prevent it from keeping the gas valve open. Thus, while the pilot light can turn on, it is unable to stay on.
You can easily clean this with sandpaper, be sure to turn the gas valve off and wait 10-15 minutes before doing so.
Bent Thermocouple
If your pilot light is still not staying lit after checking or cleaning the thermocouple pipe, check to see if the tube is curved or bent at all. This device should be straight, not bent or curved. It cannot function properly if it is bent or curved and not aligned with the pilot. It cannot receive the heat signal bent, which triggers it to keep the gas valve open.
You can try to fix this yourself. Turn off the gas and allow the thermocouple to cool down. Once cooled, you can try to bend the pipe back into position towards the pilot light. If this doesn’t work, you may need to call a professional to fix or replace this.
Damaged Thermocouple
If there’s no dirt buildup to your thermocouple, and the pipe is not bent away from the pilot, the cause for your pilot light not staying lit may be simply because the thermocouple itself is damaged. It could be missing a chunk, or the metal could have eroded, among other possible scenarios. If it is damaged, though, it won’t be able to supply sufficient voltage to keep the gas valve open.
You can use a multimeter to test if the voltage is 20MV or above. If it isn’t, then the thermocouple is damaged and needs to be replaced. (Be sure to turn off the gas valve before testing).
Faulty Electrical System
Having a faulty electrical system can be a big pain. If the internal wiring hasn’t been installed or manufactured correctly, it can cause all kinds of issues in your water heater – and one of these issues is preventing your pilot light from staying lit.
A faulty electrical system can occur during the installation of your water heater or simply from the malfunctioned water heater itself. Poor wiring exposes the fuse to the risk of burning out and/or can shorten the circuits, shutting down your water heater. A breaker shutdown can detect a broken electrical system.
Faulty Burner
If your pilot light still doesn’t stay lit, the burner in your water heater could be the culprit. The burner is the plate which the physical flame is produced from. It produces a stable flame when enough air cycles into the combustion chamber. If this device is defective or if there is sediment buildup on it, it will not be able to keep the flame alive.
The easiest thing you can do to fix this is to remove the dirt that may be clogging up the burner and then flush it out. If that doesn’t work, it could be a wiring issue with the burner. If that’s the case, you will need to call a professional to get this fixed or replaced if need be.
Main Control Valve
If nothing else fix the issues, your main control valve may be broken. This is a rare scenario, however. More often than not, the issue with your pilot light not staying lit will be something other than a faulty control valve.
There is only one way to determine if this is the problem: to eliminate all other possibilities. You can try to use a multimeter at the thermocouple to test the voltage, but that may not mean the main control valve is the problem. Main control valves seldom stop operating correctly.
If you have eliminated all other possibilities, then it may be time to call a technician to get this part repaired (however, you may want to consider getting it replaced, as it could cause issues again later on).
How Do You Fix a Pilot Light That Won’t Stay Lit?
There are a few ways you can fix your pilot light if it doesn’t stay lit:
The easiest thing you can do yourself is to remove the dirt buildup. Check and clean the pilot tube, the thermocouple, and the burner. Once you’ve removed as much as possible, flush the system with water. Dirt buildup is the most common reason for a pilot light not staying lit.
If that doesn’t solve it, inspect the pilot tube and thermocouple to ensure they aren’t damaged or bent. If there is a bend/ curve/ kink in either of these, you can try maneuvering the pipes yourself to straighten them out. If this doesn’t work, there could be damage to one or both of them. You will need to call a technician to get this fixed or replaced.
The burner could also be defective. If you suspect this is the case, you will need to bring in a professional to fix or replace this.
Finally, if nothing else solves the issue, it could be your main control valve that is faulty. You will need to get this replaced if this is the case.
What Do I Need to Work on My Pilot Light
Be sure to turn off the gas valve and allow time for the water to cool before attempting the following.
You will need basic tools, such as a wrench and a screwdriver. These tools can help you loosen certain parts to clean the inside. The sizing/types may vary depending on your water heater and the areas you try to fix.
You will also want sandpaper to scrub surfaces free of sediment buildup and a garden hose to flush it out. You can attach the garden hose to the drain valve to use the water to flush.
As for anything else you may need to fix it, the only other tool you may need is a muscle to straighten out pipes or to align pipes to the proper place. Aside from this, there is nothing more you can do other than call a technician, as other necessary repairs or replacement parts should only be taken care of by a professional.
Related Questions
Why is Water Heater Pilot Light Lit But Burner Won’t Ignite?
If everything else with the pilot light is working and only the burner is causing issues, it is likely due to one of two reasons:
- Dirt and sediment are built up on the burner, blocking oxygen from ventilating and allowing the light to stay ignited.
- The burner is defective. This could be due to poor wiring during the installation of the water heater.
Why won’t my pilot light keep a flame?
If the pilot light in your water heater won’t keep flame, and you’ve determined that the thermocouple is not damaged, bent, or obstructed, and has no other issues, then it is likely one of these reasons listed below:
- A dirty or twisted pilot tube
- A faulty electrical system
- A dirty or defective burner
- A broken main control valve
When Do I Need to Call a Professional to Fix the Pilot Light?
You will need to call a professional to fix the pilot light when the issue is not due to sediment or dirt buildup, and you’ve checked out and straightened the pilot tube and thermocouple. This is because any other solutions require the repair or replacement of parts: A job only a trained plumber should do.
Final Thoughts
The reasons behind a pilot light not staying lit will be a couple of different things to note with the thermocouples, the burner, and checking the tubes.
There are other water heater problems with more depth in each category, but those are the main things that can go wrong with a pilot light, and the number one thing is to make sure there is no buildup of any kind on it, and to clean it up and knock off the buildup if there is any.
