My machine: 6 yr. old Pavoni Millennium Europiccola

Today, immediately after pulling a blank shot, there was a loud bang or pop from inside the machine. The power light went off, and a little bit of gray smoke escaped from the top of the boiler.

Haven't inspected machine yet to see if there are obvious signs of damage. The only indication that there was anything amiss was that yesterday and today the machine seemed louder than usual once reaching operating temp. A couple of years of years ago, I had a similar symptom and posted about it here, writing, "I can't tell if it's coming from the boiler or the steam assembly, but when the machine reaches operating temp, there's a low, full-bodied hiss that sounds like a deep radiator, separated by occasional "Ch...ch..." sounds."

Ultimately, in that case, I took it into the shop and discovered that my p-stat needed replacing. Once that was done, the machine worked perfectly until now.

There have been no signs of leaking, or any other indication that the gaskets and seals have failed, which were changed at that time.

The sounds today and yesterday weren't exactly the same as before, but similar. But 2 years ago, there was never any loud bang or pop, and the power light never went out. Do you think it's the p-stat again? The heating element? A circuit break? All of the above?

Is this a catastrophic failure, euro-pav-wise?

Use a light and look at the heating element. Do you see any cracks in the metal coil? If so this would explain it heating faster. It would be time to replace the heating element.

Was the water level in the tank very low initially? If so you could have blown the thermal protect fuse too. Did you have to reset it?

There was definitely some kind of explosion. There's no sign of damage on the outside, but I keep a towel wrapped around the base to catch water dripping from the steam knob and arm. The part of the towel that was on top of the base directly behind the boiler was covered in black soot, as was part of the counter top under the machine. There was a small hole in the towel, too. There were also a few bits of black stuff around -- looked like part of the black bottom of the machine, though I didn't see any damage to it.

I have been filling the boiler to about 1/4 inch below the top of the sight glass. I never start a session with less than that, though occasionally if I make 2-3 shots in a row, I wind up with the sight glass very low. But in those rare cases, I turn the machine off as quickly following the 3rd shot as I can.

FWIW, the machine seemed to be functioning properly, apart from the unusual noise, i.e., it seemed to heat up in the proper amount of time, and was not cycling too quickly.

Haven't yet examined heating coil. No, I've never tried resetting fuse. Should I? How?

Thanks.

If you're curious, it was the power cord. There was apparently a short. The explosion blew a tiny hole in the cord, near the base of the machine. That was the source of the black smoke, not from anything inside the boiler. In fact, the cord has been replaced, and the machine works like a charm!

Still not sure if my raising the lever to pull my blank shot contributed to the failure. Or, if there's still a danger of another short. The outlet seems fine.

Please let me know if I should be doing something I'm not, or vice-versa.

The original power cord was 120V. The new one says it's 125V. Not sure if this matters.

The voltage is less important than the amperage or wattage that the cord is rated at. Cords short from a cause- wear against a sharp part, a failed strain relief or grommet, decaying insulation from chemical or ozone exposure, manufacturing defects, stray bullets, chewing rodents, etc. It sounds like you will be fine. Glad it happened with someone home since the towel could have ignited causing more problems than a dead espresso machine.

Hmmm... Like I said the hot side of the power sought ground and shorted to the frame...