I hope this tempered water heater has been retired by now. Because what you did is a hack and defeated the burning chamber overheat prevention feature..

The OEM part Thermocouple has a built-in temperature fuse. While the universal Thermocouple available at home improvement store does not. That's why the manufacturer chose the left-hand thread to prevent universal right-hand thread thermocouple can be used to replace the OEM thermocouple at the first place.

The new Whirl Pool FG model tune-up kit has left to right-hand thread adaptor to work with the original thermostat, and the temperature fuse has been put into a separated piece of hardware. The new assembly kit thus uses the universal right-hand thread Thermocouple.
There are a couple of different models for each size and BTU water heater. Choose the one made for your model.

https://www.lowes.com/pd/Whirlpool-W...Up-Kit/3435164


On Sunday, October 28, 2012 at 10:56:49 AM UTC-6, Bob F wrote:
The thermocouple on my 7yo Whirlpool water heater went out Sat. The stores open
on the weekend had only right hand thread thermocouples, and as far as I could
find out, the manufacturer would sell me a conversion kit for $31 which would
take 10 days to receive. (out of warrantee)

My solution: I carefully clamped the threaded fitting on my old thermocouple
end-to-end in my vice so one face was up, then used a 1" cutting disc in my
dremel tool to cut a slot into the fitting so I could slide it off of the tube.
I slid the threaded fitting on my new thermocouple down out of the way, then
slipped the slotted one over the tube and carefully screwed it into the valve
fitting. It works perfectly.

If you have a several years old Whirlpool or American Products water heater, you
might want to check to see if it has the left hand thread on the thermocouple.
If it does, and it is still in warrantee, contact the manufacturer now so you
can get the conversion kit for free ahead of the time you really need it.

The early symptom of failure on my thermocouple is that it took 1 1/2-2 minutes
of holding down the pilot light to get it to re-light and stay lit. The new one
took about 20 seconds.