Hi guys,

I recently bought a Pavoni pro... older unit not sure what year (its got an orange base). The guy i bought it from rebuilds machines as a hobby, said its got new boiler and gaskets. Seems to work fine, just cant get a good shot, they all taste really really bitter. I know my Maestro plus grinder isnt fine enough (going to try and do the mod for it) i did get some ground with another grinder, it choked the pavoni, then tired a less fine grind, got good resistance from the press, and got some crema, still very very bitter. when i got the machine i used a product called Cleancaf its a cleaner and descaler. I did that cause the machine wasnt fully clean when i got it, the group head screen has some holes blocked. So I thought the boiler had buildup or something, so i emptied it and waited for the water to cool, tried a sip of the water...had a weird taste, could that be making the shots bitter? and how do i do a full scraping and cleaning of the boiler? i think i get very small particles in my shots, small enough to go through the portafilter holes.

Thanks for any help!!

Welcome Alex! I have a pre millennium EP that I bought used off of ebay. Was in mint condition being used maybe 2-3 times. Wasn't sure the last time the boiler saw water so I descaled it. Now some say to flush it a couple times to get rid of any residue, but to play it safe I tripled that amount. I then ran a bunch of shots - all of them sinkers. I then filled a glass with solution and cleaned only the grouphead. Flushed a few more times and was pretty confident I was good to go.

May I ask where the water you are adding to the boiler is coming from and when you say particles, what do you mean? Pieces/shavings of metal?

ya i flushed it out a few times more then they suggested on the packaging. The pieces are so small cant tell what they are, they are only visible in water and i have to let it sit a few minutes for them to settle. I use Britta filtered water

If you have not, consider disassembling the group and cleaning the seals and the screen.

Flush until the water is clear?

I did that, the screen was clogged a bit. Cleaned seals, piston etc

My recently acquired Pavoni had some sediment, too. After doing what you did, I filled the boiler about 1/3-1/2 full of water and then gently shook the machine, and dumped the water out. I then let it drain upside down in a dish drainer overnight. Don't forget to remove the grate on the drip tray first. (Don't ask how I know this). This seems to have taken care of the sediment problem.

The manual describes the "commissioning" procedure, which includes this step:

Prepare a water solution with two teaspoons
of bicarbonate in a container and wait for the
bicarbonate to dissolve completely; then pour
the solution into the boiler.

Alternatively, instead of using bicarbonate,
prepare in a container a solution of water with
a tablespoon of white vinegar and pour it into the boiler.

You then pull some blanks. You might want to try this as it might improve the taste. If you try this, you'll want to do the shake and drain afterward to clean out the boiler.

Final suggestion: have you tasted boiled Brita water? Maybe it's just not tasty stuff. I'm being serious, BTW. Brita water tastes bitter to me right out of the carafe, and I'm not sure that boiled water tastes good ever.

michaelbenis wrote:You may simply be overextracting. Try dialing back the grind a bit....

dont think its over extracting. it isnt taking 20 sec to pull the shot.

Heilmittellehre,
will try what you wrote...


thanks all for all the hits/help!!!!
cant wait to get decent shots, its now my only espresso machine and i need my fix! maybe i should get a cheap basic pump machine for now til i get this working properly....hmmmm

As i had the machine turned over to see is sediment would come out, i decided for the hell of it to remove the element, the element looks spotless, brand new like the seller told me, but look at the inside of the boiler tank...ewww, ran my finger in it had a green residue....what should i use to clean it? and would that give me the bitter taste?

I would be tempted to first wipe out the boiler with a paper towel. Since the stuff comes off on your finger, no sense going wild with chemicals and wire brushes. After that, maybe a scrubbing with baking soda. I would think that baking soda would be safe, and would polish up the boiler nicely. If the green stuff is related to the bitterness you're tasting, the soda should help to neutralize it.

One other perhaps remote possibility is that you've got a keen sense for bitter tastes. If possible, you might want to see if others (ideally not genetically related to you) also taste the bitterness. You might be sensitive enough that you taste something that most people don't, and it might be something you can't clean out of the Pavoni.

My sister-in-law finds it bitter and gross too. Will do a complete deep clean and post results..to let others know if they come across the same issue as me

That green residue is a little creepy! Verdigris?

Please let us know the results of the clean-up process. A superb shot of espresso is surely just ahead.

I found that in addition to cleaning the boiler, which had residue that tasted bitter from the lime build up, I needed to disassemble the head - gaskets, seals et al - and soak the pieces in a white vinegar solution. The deposits were like creosote! It took some time and effort as the lime salts and tar are very tenacious.

When putting it back together I used the correct silicon lubricant. I couldn't believe the difference in quality. Like a new machine.

Before drinking the coffee, I ran a vinegar solution 3 more times, then rinsed 5 times. I was surprised with how much fine sediment there was - which went through the filter.

A shot under 20 seconds may taste bitter to you as well. Is it watery-bitter? From my recollection, levers can tend to run longer shots, (like 30-40 seconds?) while still tasting good. Choking is too fine of course, but maybe you're back too coarse again...?

mindless_fool wrote:dont think its over extracting. it isnt taking 20 sec to pull the shot.

In my experience with a Pavoni EP you certainly can and should have an excellent shot if the extraction time is around 20 seconds, which should be in ristretto territory. However this does require a decent amount of resistence in the lever pull down - to the extent that you need to hold down on the boiler cap as you depress. You have to work for that espresso man! If you are not finding this, and that your pull down is "easy" with little resistence, then you will get bitter/underextracted shots. This comes down to tamping, grinding and dosing. A full dose, with a hard tamp/coarser grind or soft tamp and with finer grind should give you good results,

The other cause of bitterness is water that is too hot. The Pavoni's are notorious for overheating, even after a single shot if you dont allow them enough cool down time, or use ice cubes or cold damp cloths to force the cool down more rapidly.

Better than ice or a damp cloth, don't let it get so hot in the first place. It is already difficult enough to try and hit a good temp on the way up, let alone trying to cool it down to the sweet spot.

New-to-me Europiccola!