Thermocouple for older boiler

[DougB]

I have a boiler from 1950. With a standing pilot. That needed a new thermocouple.

I've discovered that replacement thermocouples have two different thread sizes on the gas valve. After buying one (Honeywell) that didn't work, I managed to find another that worked, but doesn't fit well in the 'flame holder'.

I looked on Amazon and Grainger - but there are no descriptions on the thread size, and are very vague about mounting.

Anyone know of a better site for thermocouples?

 

[Dana]

Is it the original 1950 gas valve? (If yes, it's worth considering replacing the whole assembly, if not the whole boiler!)

 

[Sponsor]

 

[DougB]

I was looking for a source of thermocouples that was more descri

Is it the original 1950 gas valve? (If yes, it's worth considering replacing the whole assembly, if not the whole boiler!)

As I said "Anyone know of a better site for thermocouples?"