On Sunday, October 28, 2012 10:56:53 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.

Although your post is from last year, I recently had a problem with my 6-year old GSW water heater with a left-hand thread thermocouple.

I am awaiting a free warranty replacement for the whole assembly minus the burner head but while waiting I substituted a brand new $9 RIGHT-HAND thread thermocouple with a slight modification. Rather than cutting a copper line and splicing things together etc., all I did was slide the threaded piece (part that screws into the control box down a ways from that tip, held the piece with a small pair of vise grips and set it against my bench grinder wheel to wear off the threads, I did this on all sides and was left with a smooth piece, still with the 7/16" hex head though. Next I stuck the end right up into the control unit and while holding it in place, took some strong wire, wrapped a fair amount around the copper line that exits that fitting and then just "tensioned" it up by wrapping the wire up higher near the gas line fitting. The pilot stays lit BUT if you look closely at where the end of that thermocouple screws into the box (the female end left-hand threading), there's a small light blue plastic tab that gets depressed when the lefty is fully screwed in. My jury-rigged thermocouple end has no threads so it can't strip that entry point but it's still doing its job: 1. pushed up as far as it can go. 2. pulled tight with wire and held UPWARD. 3. pressing on what appears to be something of a plastic locking tab that IF not pressed in OR when I did happen to move around the now non-threaded piece and the baby blue-colored tab moved, out went the pilot.

Apologies in that I don't know the terms or names of some parts but I was just so excited that I was able to fix this temporarily until I get my replacement kit. Also, after a few decades of replacing the odd thermocouple in my old furnace, I finally figured out that the reason some of my other ones went was because of a tiny hairline crack at the tip of that pilot. Hard to see at first but I kept a few of the older ones and sanded them a bit to verify that such an issue exists for these cheap parts.