Hello all,

I've been reading this forum for a while and decided to give a lever machine a shot . So I bought a new Europiccola (millennium). I was under the impression that these machines should be almost entirely silent, but it turns out to be quite noisy while heating up - sort of a popping/cracking/water turning over noise. It makes sense that the boiler would make noise, but I don't recall hearing it in my first couple uses, and I have never seen any discussion about it. Probably just paranoid about my new purchase. It is actually possible to feel the sound/vibration on the counter top. Is that normal?

Thanks for your input.

Mine made the roaring sound as well. I ended up enjoying hearing it in the mornings.

Quite normal. Water is boiling in the "boiler," air at first vents out of the over pressure valve until the machine comes near operating pressure. Some air and steam can vent through the over pressure valve later, but that shouldn't be constant. Enjoy your lever experience!

Liquids commonly become "super heated" when they are heated. Bubbles have to form in order for liquids to vaporise. Surface tension results in there being pressure inside bubbles. The physics formula for this is P=2ɣ/R, where ɣ is the surface tension and R the radius of the bubble. Bubbles have difficulty forming in clean liquids with only smooth surfaces, because the pressure inside small bubbles is inversely proportional to radius. When bubbles do finally form and they get large enough to expand against the surface tension they expand almost violently because the surface tension pressure inside falls as the bubble expands. If you put pure water in a clean test tube and heat it, boiling will not occur until one gets well above the boiling point, and once bubbles form they form violently, so water can shoot out of the test tube.

Water inside boilers makes noise from the mini explosions that occur from this. As boiler heating elements age they are likely to develop coatings that can help create bubbles.

Liquids with low surface tension do this much less, and adding materials to the water that reduce surface tension will reduce it, but we do not want to put pollutants in espresso water!

(Sorry for the physics lecture.)

I thoroughly enjoy the physics and chemistry lessons you provide - and suspect many others do as well.

rpavlis wrote:Liquids commonly become "super heated" when they are heated. Bubbles have to form in order for liquids to vaporise. Surface tension results in there being pressure inside bubbles. The physics formula for this is P=2ɣ/R, where ɣ is the surface tension and R the radius of the bubble. Bubbles have difficulty forming in clean liquids with only smooth surfaces, because the pressure inside small bubbles is inversely proportional to radius. When bubbles do finally form and they get large enough to expand against the surface tension they expand almost violently because the surface tension pressure inside falls as the bubble expands. If you put pure water in a clean test tube and heat it, boiling will not occur until one gets well above the boiling point, and once bubbles form they form violently, so water can shoot out of the test tube.

Water inside boilers makes noise from the mini explosions that occur from this. As boiler heating elements age they are likely to develop coatings that can help create bubbles.

Liquids with low surface tension do this much less, and adding materials to the water that reduce surface tension will reduce it, but we do not want to put pollutants in espresso water!

(Sorry for the physics lecture.)

Um ... that's what I was trying to say. Thank you Robert, once again!

jingram1, First I would like to congratulations on your purchase . La Pavoni Europiccola one of the best lever espresso machine. I sold mine two years ago.( Yes, I missed her ) I like piccola because it is small in size, very portable, easy to bring to anyway I like and easy to make great espresso even you are in camping. I will definitely buy one again, but I wish I could get one in FULL COPPER one

I appreciate everyone's responses! Glad to hear there's nothing wrong.

rpavlis wrote: Liquids with low surface tension do this much less, and adding materials to the water that reduce surface tension will reduce it, but we do not want to put pollutants in espresso water!

Excellent explanation. When I first used the machine, I don't remember hearing this noise. However, my first two runs were to descale/clean it - I used Urnex descaling powder. Perhaps it contained a surfactant that minimized this effect. Is that possible? I wasn't able to find a full ingredients list, but some of Urnex's other products say they contain surfactants.

CoffeeBar wrote:jingram1, First I would like to congratulations on your purchase . La Pavoni Europiccola one of the best lever espresso machine. I sold mine two years ago.( Yes, I missed her ) I like piccola because it is small in size, very portable, easy to bring to anyway I like and easy to make great espresso even you are in camping. I will definitely buy one again, but I wish I could get one in FULL COPPER one

The size is great because it heats up really fast. I too wanted the brass/copper one, but I had to exercise self control.

I've had pretty good results so far, decent espresso with lots of crema. Quite low shot volume (~30ml), but I am pretty sure that's normal. Haven't been able to make microfoam yet, though. I haven't even gotten my 51mm tamper (using a 49mm one from my ROK) and frothing pitcher, so I'm hoping that leads to an improvement.

jingram1 wrote:I've had pretty good results so far, decent espresso with lots of crema. Quite low shot volume (~30ml), but I am pretty sure that's normal. Haven't been able to make microfoam yet, though. I haven't even gotten my 51mm tamper (using a 49mm one from my ROK) and frothing pitcher, so I'm hoping that leads to an improvement.

I hope you enjoy the journey. The learning curve is part of the fun of this hobby!

Dr. Pavlis and others have written about how to get rid of the air pocket that creates a spongy pull and achieve larger shot volume. Here's an example of someone who's found the zone:

La Pavoni Spongy Pulls

Thanks!

I followed some tips in that thread and just got a more satisfying pull with resistance all the way through (I barely noticed the lack of resistance at the beginning of the pull earlier). The volume was 33ml as opposed to 28ml without the new technique, and it tasted better as well. A little bitter, but I prefer that to under extraction.

Can only get better from here.