I've got a funky one for you on one of my KGL 100 kettles.
I got called over today, they had 15 gallons of water in the kettle, on full blast. Wouldn't get to a boil.
I dry fire the unit, PSI cuts off at around 40 PSI on the dot. From what I understand, 40 PSI steam is at around 287 *F.
The other unit they are comparing it to, cuts off at 45 PSI which is closer to 300*F
The 1st unit (the one that cuts off at 45 PSI) is working fine and they are happy with it.
The 2nd unit (the one that cuts off at 38-40 PSI is not good and they are not able to use it for certain things due to it being like this.
I Then went to look at everything, potentiometer is fine, thermostat is fine, it's consistently shutting off at 40 PSI, not varying at all, they use it fine when there is more water in it which is what is so odd about it. I then tried to turn up the potentiometer on the controller, didn't change anything.
When I first learned to calibrate these I would set them too high and they would blow the valve in the back so I know they can go above 40 PSI, so I put a new controller in, still wouldn't go above 40 PSI so I jumped out the high limit and then it would go above 40 PSI. So to me it seems the high limit is failing.
So I checked the specs on the high limit, seems like it cuts off at 140-150*C (140*C is 284*F, 150*C is 302*F)
So I'm thinking it's shutting it off early and that I should replace the high limit.
They want the water at a furious boil around here, I think they got a name for every kind of boil you can imagine but the one where you can barely see the water because there is so much steam, and it's ALMOST boiling when it shuts off, I think the extra 10*F might be what's killing the mojo here, that's the only big difference I see between the 2 kettle's.
What do you think, am I missing something?