Quaha Napolitana II assitance required.
I recently replaced my boiler element in my Quaha and also replaced the steam thermostat with a 140c . The machine worked like a charm for two days and then this morning started to trip the safety switch. I stripped it down and can see the element looks like is overheated with the copper showing distinct signs of malformation due to overheating. I checked the all the thermostats with my Fluke and they all around 0.1 ohms. Any helpful advice would be appreciated.
Possibly the new Steam T/stat was faulty, in that it allowed the element to overheat rather than control it to 140C.
If you've done nothing else to the machine, then that is a possibility...
The other possibility is that you may have overstressed the element when fitting and cracked the vitreous insulation at the connection points. If so, this will allow moisture ingress and cause the RCD protection to trip the power.
I have replaced two machines with 140°C steam thermostats without issue. Not sure what may have happened.
Maybe the new thermostate exceeds 140°C. But I would think a masive over temp would result in the 175°C safety triggering.
Not sure what you mean by the copper showing distinct signs of malformations. Are we taking about the electrical connectors?
Increasing the temperature stresses the components more. Maybe you had a small leak that with the increased pressure from higher temperature causes leakage? Not much earth leakage is required to trigger an RCD.
Dimal might be right about the element insulator.
Not much info to go on.