Brew pressure
An adjustable valve, for a technician
There is no pressure gauge and no pressure setting for owners. The pump's pressure is limited by an adjustable over-pressure valve, which the US manual calls the safety valve, returning surplus water to the tank.
Rancilio's 2019 manual and its current US manual give this on a page headed "This operation should only be conducted by a qualified technician". The 2024 EU manual drops the page altogether. Rancilio gives no factory pressure. What others say is listed below so you can see the spread.
What the manual shows the technician
Rancilio's 2019 manual and its current US manual give this on a page headed "This operation should only be conducted by a qualified technician". The 2024 EU manual drops the page altogether. These are the steps on that page, for reference.
- Unplug the machine and wait until it has cooled completely.
- Lift the tank out, remove the four screws on top and lift off the cup tray.
- Loosen the lock nut on the valve.
- Screw the adjusting screw in or out by 1 turn at most.
- Tighten the lock nut.
- Refit the cup tray and its screws.
Rancilio's drawing marks + and − beside the screw but does not make clear which way is which. Videos of older Silvias hold the valve with one 20 mm spanner and turn the lock nut with another; one says clockwise raises the pressure. They read the result with a gauge on a blind basket.