Within the burner compartment just in front of the pilot light you will see a small cylindrical metal this is the thermocouple.
Water heater thermocouple position.
If the pilot light blows out the voltage stops and the gas valve is automatically closed.
Then snug them up with a quarter to half revolution with a wrench.
The thermocouple is a heat sensitive electronic device that generates a small electrical signal when it reaches a certain temperature.
When relit the water heater pilot light flame should wrap around the thermocouple bulb.
Use wrenches or screwdrivers depending on which you need to loosen the nuts and screws on both ends that connect the thermocouple to the water heater.
Position it according to the manufacturer specs so it is fully immersed in the pilot flame.
To reattach the three lines to the gas valve thread the nuts into place with your fingers and hand tighten them.
This will disconnect it on both ends.
Pull the thermocouple from the pilot bracket attached to the manifold burner assembly.
How to test a thermocouple.
Position it exactly like the old one.
Detach the thermocouple from the whole.
This voltage is used by the hot water heater thermostat to hold open a gas valve.
Before you can actually diagnose and identify that the problem has something to do with the thermocouple you have to know where it is located.
It is a simple device that converts the heat from a burning flame into a small electrical current allowing it to work like a switch to control the flow of gas from the gas supply valve.
It is used to detect whether the pilot light of the furnace is lit or not.
If the pilot light doesn t stay lit check the gas water heater thermocouple by keeping the pilot button depressed.
It is directly connected to the furnace s gas valve.
This pilot light heats a thermocouple which generates a small voltage up to 30 millivolts.
The thermocouple is part of the pilot burner assembly and connects to the gas control valve on the outside of the water heater.
If you experience the pilot outage a thermocouple might not be in contact with the pilot light.
Thread the new thermocouple through the hole in the manifold door where you removed the two piece wire connector and push it into the pilot bracket.
When the pilot lit goes off due to the loss of heat this device detects it and it cuts off the fuel supply.
A thermocouple is a safety device that is attached to the gas furnace.
Slide the thermocouple out of position.
Thermocouples are used as safety devices that will shut off equipment by shutting down the lp or natural gas fuel supply on some gas fired heating equipment such as gas fired furnaces gas fired heating boilers and gas fired water heaters.
