Remove burner assembly.
Gas water heater thermocouple replacement.
Make sure that the gas controller is in the off position before attempting this repair.
Honeywell home cq100a1005 u cq100a1005 replacement thermocouple for gas furnaces boilers and water heaters 36 inch 4 7 out of 5 stars 188 9 79 honeywell cq100a1021 u cq100a1021 replacement thermocouple for gas furnaces boilers and water heaters 18.
If the thermocouple is working you should be able to measure 30 to 40 millivolts of voltage at the connection end of the tube when the pilot flame is on.
How to replace the thermocouple on a standing pilot water heater.
Step 8 reattach the manifold tube pilot tube and thermocouple to the gas control valve thermostat and tighten them using the adjustable wrench.
Turn off the gas supply.
For example sid harvey s dyna couple universal mounting thermocouple sold in lengths from 18 to 48 will replace honeywell robertshaw penn baso white rodgers and other thermocouples.
Then unfasten the three nuts that hold the thermocouple and the two gas tubes to the valve.
A new one costs about 5 to 10 and is easy to install.
The thermocouple has two ends.
Unfasten the three nuts that hold the thermocouple and the two gas tubes to the valve.
First shut off the gas valve on the water heater and the gas valve on the gas line near the heater.
Replace the two piece wire connector onto the thermocouple and igniter wire securing it with the retainer clip and slide the manifold burner assembly back into the water heater.
Then detach the thermocouple from the burner and take it with you to the home center or hardware store to ensure you buy the right replacement.
Replacement thermocouples using universal mounting include clips and fittings that will work on most gas fired heaters and water heaters.
How to replace a gas water heater thermocouple with video instructions turn off the gas supply to the water heater by using the gas control valve or the main valve.