La marzocco linea pb x

[mangga88d (Mangga)]

@mangga88d

Where can i learn more about espresso machine? iany channel or books about machine.
I have issue when machine turn on first early in the morning. The pressure gauge goes up to 15bars before it slowly come down 9 bars. How can i set it not goes to 15 bars. Just want max up to 12 bars? Is it this overpressure valve adjustment?