There are three pressure gauges, left is for brew boiler ,right for steam boiler and top for extraction I think ?

so the top one is meant to be calibrated at 9 bars and this is what I want when extracting. Do I have to pay any attention to the two bottom gauges ?

Also I heard that some machines arrive calibrated at 11 bars, that can be easily changed…. But how do you know if it’s at 9 or 11 bars ? Isn’t grind size going to determine that? How to check that before extraction,

Thanks in advance.

    MuddyOne The gauge on the left tells what the pressure in the steam boiler is - e.g.: if it’s pressurised or not, and if so, by how much;

    The gauge on the right tells you the pump pressure - If it’s a rotary pump machine it will tell you the pressure of the pump, not the pressure of the circuit.

    The gauge on the group tells you the pressure at the group, which can be controlled by the little lever (flow control) on top of the group. So you can profile your shots.

        MediumRoastSteam

        Thank you, so during extraction I should not be concerned with boiler gauges they just show that they are charged up.

        I still don’t understand what is this about,found in several places but this quote is from home barista forum.

        “Most people receive their machines with the rotary pressure between 10-11 bar. You can certainly adjust it to 9 bar”

        I have seen video where guy adjust with screw from somewhere on bottom of his machine back to 9 bars.

        I’m confused here, we adjust our grind size to aim to 9 bars typically,what is that they are talking about?

            MuddyOne - you can adjust to whatever you want. The nominal adjustment is 9 bar. But that machine you are looking at, has a flow control, so you can also adjust the flow rate, which in turn will influence pressure, during the shot.

                MuddyOne - buy the machine, use the machine, get to know your machine. Then you think about adjusting things. So no, don’t worry about it.