The electrician didn't do anything except confirm that the machine has a fault that is blowing fuses. Resistance is not a part, is an electrical property of the part. Electrical current is the voltage divided by the resistance, so if you don't have enough resistance you get too much current. The fault could be anything from a bad switch to shorted terminals on the heater. Essentially you have to take it apart and check the components. My procedure would be to do a visual inspection first for bad insulation, electrical terminals touching each other or the metal parts of the machine, cracked heater, signs that water is leaking into the circuitry, etc.
If the machine blows the fuse even when it is turned off, the problem is almost certainly the power cord or at the switch. The most likely place for the power cord to fail with a short (other than an improperly installed replacement plug) would be where it goes into the machine. Look closely for cracked or broken insulation both on the inside and the outside of the machine.
After that I would use an ohmmeter to check the electrical resistance of parts. For example, if the coffee pot is rated for 10 Amps, the heater resistance should be 120 Volts / 10 Amps = 12 Ohms. Since your model is rated between 800-1000 Watts, (7.1 - 8.3 Amps), the heater resistance should be at least 14.1 Ohms. The indicator lamp should read "out of range" if it is a neon bulb, but may read several ohms if it is incandescent (the resistance of incandescent bulbs increases as they get hot).
One possible source of the problem is a leaky steam pressure switch. If water is getting into the electrical part of the switch, it could be causing a ground fault.
If the power cord is bad, you can cut off the bad part and rewire with the remainder (if it is still long enough for you), or you can replace it with any 16 gauge power cord of the same style rated for elevated temperature use. "For La Pavoni replacement parts
and service, please
contact La Pavoni USA at
1-800-927-0277" (from the
Pavoni website).