What you will learn from How to Test Thermocouple with MultiMeter article How not to guess if the thermocouple is bad.
What is the thermocouple millivolt range for good thermocouple What is the thermocouple test procedure.
How to Test Thermocouple with MultiMeter The thermocouple fits in the burner ..
Thirdly, start the flame and put the tip of the in the fire..
Next, ensuring the tip is nice and hot from the flame, take one lead from the meter and put it on the shaft of the thermocouple and the other lead and put on the end of the thermocouple where it makes contact with the gas valve..
Finally, if the reading is less than 25 millivolts replace the thermocouple as most standing pilot gas valves need 25 or more millivolts to keep the pilot flame lit.
If the tip is in the flame, you have held the nob on the valve down for longer than minute, the pilot flame is strong and steady, and the pilot still does not stay lit, then you have problem with the valve.
Therefore, the valve could not open.
From the junction, stem runs length from the body of the thermocouple tip to the gas valve..
the inside the valve remains open.
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