Product review (5 stars): Great part in card cardboard and plastic window .
This is a decent thermocouple , remember it's a right hand threaded thermocouple , use your fingers ! Make sure it's threaded at least 3 to 4 threads , did you make sure your old one is tight?
75 % of them time the threaded end isn't as tight as it should be , first thing I do is by hand try to unscrew it , if I can it's prolly what's wrong , these parts work on millivolts and that's a whole nother story ,
1.  Is thermocouple tight
2.  If this is a water heater is the air inlet clogged and if it has a vapor filter is it clear from dust and lint ?
3.  Make sure the pilot is near the thermocouple not in the flame just 1/4- 1/2" away ,

4. Make sure the new one is tight and not kinked.
Questions I can help you
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