Hot Water Heater Pilot Light Keeps Going Out

It can be both mind-boggling and infuriating when your pilot light on your hot water heater won’t stay lit, and the fix may seem daunting if you don’t know what you are looking for. These six reasons should cover why your pilot light keeps going out and the best way to fix it helping you get hot water once again flowing through your taps as soon as possible. Once you know the cause or causes of your pilot light failure you can prevent future problems by knowing what to look out for.

1. Obstruction of the Thermocouple.

The majority of hot water heaters operate with the use of a thermocouple. The thermocouple is vital to the operation of a hot water heater by checking whether the pilot light is on or off via an electrical current that is produced by the heat of the flame. Whenever the thermocouple notices that there is no electrical current is will disable to gas flow into the unit as a safety precaution.

If the thermocouple is dirty it can fail to pick up the electrical signal thus preventing the gas flow and failure of the pilot light. The solution is easy, simply clean the thermocouple gently with a piece of sandpaper but ensure that the mains gas supply is turned off before doing so to prevent leaks or potential problems.

2. Damaged Thermocouple.

If you a sure that the source of the problem stems from the thermocouple and you cannot see any bending or dirt, then you are more than likely suffering from a damaged thermocouple. The only way to fix a broken thermocouple is by replacing the device with a new one or having it professionally repaired. Make sure that the gas is switched off and that the thermocouple is cool before removing it. You can also check whether the device is damaged by using a multimeter to test the voltage coming from it. If the reading is showing a voltage of 20w or less then its time to have it replaced or repaired.

3. Bent Thermocouple.

Again, the usual culprit with a faulty pilot light is the thermocouple. If you have checked it for dirt and the multimeter indicates that there are no issues with it, it may be down to being bent away from the source of the pilot light. If it is bent too far away it cannot register the heat and thus it will not allow the gas flow to continue. The remedy is simple and requires you to gently bend it back towards the pilot light area. The flame should gently touch the unit or be near enough that the heat can be detected. Once bent into position check to make sure that the pilot light reaches it and that the flame is blue in color and not orange or red.

4. Dirty Pilot Tube.

After checking the thermocouple and everything being ok with it, the next step is to check the pilot tube. Dirt, dust, and grime can easily build up inside of it and block the flow of gas to the pilot light causing it not to light or stay lit. Fixing a dirty pilot tube is a quick and painless process, simply allow the unit to cool and take a sewing needle and gently scrape it around the inside of the tube. Make sure you scrape out any debris and do not allow it to drop down inside the tube. Once you are done cleaning it, turn on the unit and light the pilot light to check that it is operational if there are still issues repeat the process until it is thoroughly cleaned.

5. Flex Tube Problems.

The flex tube is a small pipe that connects to the gas controller and ensures that there is a steady stream of gas. This tube can at times develop kinks and bends that prevent the flow of gas to the unit. To remedy this issue simply remove any kinks or bends from the tubing, or if not possible have the tubing replaced. Flex tube problems are less common than thermocouple and pilot tube issues so you should check those before checking the flex tube.

6. Main Control Valve.

This is the least common cause of problems with the pilot light and should be the last thing to check after ruling out problems with the previously listed parts. The main control valves generally do not go out unless it is broken. If the main control valve is broken, the only way to fix it is by having it replaced. If all other options have been ruled out then this is most likely to be the culprit.

Now that you know what to look for and how to fix it, any problems you have with your hot water heaters pilot light can be checked and resolved with ease. If in doubt call a professional to perform a check-up and repair for you.

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