boren wrote:For those who only drink espresso and don't need to steam milk, wouldn't it be easier to change the pressostat and reduce the pressure so that brewing temperature is optimal and consistent between consecutive shots?

For those who do need to steam milk, just get another machine and set its pressure high enough so that it's optimal for steaming

As I recall, from my many years of using a series 2 LP, the optimum temperature for brewing shots requires a boiler pressure setting that makes steam available anyway. The problem is then that the little group head becomes too hot to cool down. The solution is to use the machine to make a single espresso or cappuccino and then switch it off until you are ready for another. If you need to serve more than one person successively, get a different machine.

guijan12 wrote:That does not work; optimal temperature is appr. 88C (0,7 bar).
No water will enter the grouphead at that pressure.

Not sure about the La Pavoni, but it works very well with my Elektra (MCaL). I set it to 1.2 bar, which I find to be ideal for steaming, but I turn it off and let pressure reduce to 0.7 bar before brewing espresso. When it was set to the default 1.0 bar steaming was weaker and the espresso tasted much worse. For this to work though the grouphead needs to be really hot (same temperature as the boiler). If I let the machine warm up and then try to brew at 0.7 bar (when the grouphead is still cold) the espresso turns out really sour.

I think we're getting away from the topic of the Bong Isolator. Someone posted earlier that there are many ways to control brew temperature on La Pavoni home levers, which is well handled in other topics.

I wonder if the Bong Isolator is safe to leave installed, especially the older version that deforms, and I don't know what tests have been done on the nylon version.

I'll let you know.
The nylon replacement is expected to arrive coming Tuesday and I hope to find time to install it asap.
It's time for maintenance again...

Guido, If you can, I would love to see a measurement of the distortion in your old version and an estimate of how long and often you used it.

Also, do you know if the nylon being used is food-safe? Some nylons are not.

Hi Gary, all,

I received the replacement and installed it yesterday evening.
The total distortion is approximately 1,5 mm (on 11,9 mm thickness of the Bong isolator), being appr. 13%.
And containing a small crack (see pictures attached).

The isolator has been in use since 1st of December 2020 and the LPP is my daily driver.
On average I heat it up 3 times a day to pull 2 espresso's.
So my guestimate is it has been pressed and stressed for 840 times, in the past months.

The reply of the supplier (Coffee-Sensor) has been swift and accurate, all the time.
For now I'm enjoying the LPP again and I keep a close eye on isolator!

I have some video's with the old Bong isolator and the new Bong isolator too.
The new isolator already seems less compressed by pulling the shot.
Let's see what happens in the coming weeks.

A pull with the old Bong isolator still in place:

And with the new Bong Isolator:

Hi there,

I'm interested in hearing how the nylon isolator is holding up after several months. Have you noticed any cracks or distortion?

Thanks for reminding.

It is still perfectly well and not deforming.
The pull is almost like the isolator is not installed.
So I'm still very happy with it.

drgary wrote:I see a potentially serious safety hazard. If the Bong Isolator old or new version fails catastropically, the user could be blasted with live steam if it opens at the top. There are other mods that don't have this risk, including this fix, which makes the 2nd gen group water heated instead of steam heated. Add to that a thin PTFE heat break gasket and you're not extending the lever or risking steam burns.

Heat control mod for 2nd Generation La Pavoni Levers

Interesting point. And thank you for that. But...
About old and new version, if you could be a little bit more specific towards what do you mean.
Are we speaking generation wise of the machines on which the product is installed or material wise used to build the Bong Isolator?

We did have two materials used to create the isolator, first being the Teflon (softer) and now, Nylon (harder material).

About the possible safety hazard...i would not go so far when speaking about the product, simply because from the user POV, La Pavoni is full of other funny (or not so funny after all) safety hazard traps.
People have had blown portafilters from the group head after the extraction when coffee + hot water was splashed in the entire kitchen.
Other users reported burned skin from accidental touching the boiler body before steaming and so on.
Two users have written that the boilers (new ones) had pinched point where leaks where visible with naked eye.
Not to mention the entire sight glass system which is not IMHO a good solution, safety wise.
A cracked sight glass is not very visible, because it usually happens in the upper or lower retainer.
A cracked glass under 1 and something bar is not good.

Regarding the Bong Isolator, we NEVER had safety issues like that presented, even in private.
Most common issue reported in the past was small pressure leaks on the upper part junction, between the product and the GH neck.
That happened because:
1. A lot of users DID NOT remove the old o-ring from the group head neck (they simply responded that they thought that was NOT a gasket or O-ring, being too flat and worn out), before installing the new O-ring;
2. Group heads that were not straight at the connection point with the boiler (manufacturing fault from LP);
3. Bottom out bolts (happened only on some machines, because of the non standard inside thread La Pavoni made inside the GH - solved with the shorter bolts);
4. Isolator soft material (solved with second gen material - Nylon).
This is a short presentation of the overall situation, after i think one year during hundreds isolators sold worldwide and also a lot of feedback and reviews from users.

As i mentioned shorttly above, we improved the bolts and had made them shorter (from 30mm thread length to 28mm thread length, for better compatibility with old gen machines). Overall quality of the bolts was also improved (now they are more expensive).
Also, bear in mind that the entire pulling force of the shot sits on the two stainless steel bolts and not on the isolator.
And both are screwed a few mm inside the boiler body. So we have two sitting point for the GH on the boiler, metal on metal.


Thanks and God bless,
Tudor P.