Place The brand new thermocouple where the previous just one was and fasten the thermocouple wire in the assembly plug. Move the tubes again with the manifold door. In advance of replacing a water heater thermostat, test it for continuity to make sure it's the culprit for any water heater https://leakfixsolutions.com/top-10-plumbing-repair-services-access-denied-for-top-notch-repairs/