I laugh at myself often because I will usually do things the wrong way a few times before I can figure what is right. I hope that is what's going on here. I took a close look inside the steam valve to see how it seals, and I noticed that the part in which the nylon seat presses against is raised. Therefore, the nylon seat needs to be FLUSH with the top of the cup on the end of the shaft.

Either the Brugnetti distributor sold me a nylon seat that is too long or I just didn't realize that I needed to cut it. That's what I did. I cut the end of the nylon piece with a utility knife. So far so good. It's working.

Here are some pics:


You can actually see the indention from the raised part of the steam valve that seals against the seat.

Pressure - way too high. Should be more like 1 - 1.2bar.

pstat - for some reason, brugnetti love putting them below the waterline. I know of no other make that does this. Anyways, check under the boiler. Alternatively, trace the element wires backwards. one or both will lead to the pstat. That device you referred to in the top right could be a thermostat. I have no experience with these outside of seeing them listed in my parts manuals. Hope someone else reading is of more use to you.

I have wanted to adjust the pressurestat settings on the Brugnetti but wasn't sure where to find it on this machine. I read this informative post: How to adjust an espresso machine pressurestat (boiler temperature) However, I did not see a Sirai, MA-TER, or CEME pressurestat.

The only one I found is below:



I was able to adjust the pressurestat by turning the top dial with a pair of pliers. Right now, it is cranked down from 1.5 to 1.3 BAR. That does seem to make it easier to maintain a stable temperature. A temperature setting of 1.3-1.5 is actually recommended by Brugnetti for this machine:

Brugnetti Simona Top Manual:
The yellow control lamp (000628) will light now, when boiler reaches its optimal
operating pressure between 1.3 and 1.5 bar, as shown on the gauge (# 884349), the
control lamp (# 000628) will shut off.

In a couple of days, I may crank it down to 1.2 to see how that goes. In reading others' posts, it seems that manufacturers like to set the machines to run too hot, and most users end up adjusting them to lower temperatures. Is that true? If so, why would the manufacturers do that?

According to a Brugnetti Rep, the Simona top has a relatively short HX path, which benefits from higher boiler pressure. As a side bonus, steaming power is improved.