A thermocouple or flame sensor is a device for regulating the flow of gas in gas water heaters. Often times, a bad thermocouple is the reason a water heater won’t light or a burner won’t light.
The main reasons an instant gas water heater automatically turns off is that the Check Engine Light goes out, the Check Engine Light won’t start, or there are problems with the gas supply.
Part 2 hit the reset button
- Find the red reset button. There should be a red button in the center of the control panel.
- Press the button firmly. The reset button can be sticky at times, especially if you haven’t reset the oven in a while.
- Wait until you hear the button click.
If the hot water pressure is still low, the problem may be the plumbing under the sink. Remove the bead from the valve and the bottom of the faucet and clean or replace it. Also check the outlet pressure from the de-energized valve.
Turn the water heater gas valve switch to the OFF position, wait a few seconds, then turn the switch to ON to reset the system.
If the flame is not burning at all and you are sure that the gas is burning, there is probably an obstacle in the ignition tube. If the flame goes on and off when you release the gas control knob after holding it for the recommended 20-30 seconds, there is an indication of a thermocouple fault.
A faulty thermostat is probably the cause of the sudden overheating of the water heater. A thermostat controls the on and off cycle of the boiler elements. In the event of a fault, a safety function is activated if the thermostat does not interrupt the power supply to the boiler elements during routine cycles.
Thermocouple Replacement 20 150 Calling a professional plumber to install a new thermocouple should cost as little as 150. If you do the job yourself, you only pay the price of the part, which is around 20.
Clean the sensor After removing the sensor, carefully scrub the metal rod (and nothing else) with very light sandpaper. Remember, you’re not sanding the body here, you’re just removing the debris sensor. Then use a clean paper towel to remove any remaining dust after sanding.
Close the gas tap on the boiler door handle and close the knob on the top of the temperature control valve. Use a wrench to loosen the nuts connecting the burner gas tube, pilot tube and thermocouple. Lower the gas lines and thermocouple from the gas valve.
How to light a boiler burner Open the door / lid above the burner access. Use a flashlight or headlamp to locate the burner inside. Turn the control knob and hold it down. Turn on the pilot by keeping the accelerator pedal pressed. When the flame ignites, press and hold the gas button or button for a full minute.
Step Look for the indicator light on the gas valve. Turn on the light for 30 seconds. Release the button to see if the light goes out. Shut off the gas supply to retest the thermocouple. Count to 20 and wait for the lights to go out. Listen to the click of the gas valve.