Investigation begins
After the incident yesterday our Rancilio Silvia need some service.
Before starting: make sure that the machine is plugged out of the socket to avoid electrocution.

First step
Remove the top plate

Second step
Measure heater resistans. Result 48Ω’s this would give a resulting power of 1,1kW (P=U2 / R). Sound resonable.

Third step
Check the automatic overheat protection located on the side of the boiler. This one was tripped in our machine. This was good news.

However testing the machine tripped the residual-current circuit breaker. Must be some damage to the heater after all.
Step four
Measuring the resistens to ground.

This is possibly caused by crack in the heater element. 🙁
Conclusion
A new boiler and o-ring is needed.
