NEWEST Feature: The overpressure valve (a.k.a. OPV) is now adjustable on our latest batch of new Silvias (started in February, 2007). The overpressure valve is normally set to 11 bar. However, if your grind is just right, the grind should only create 8-9 bar of resistance so the overpressure valve will never open.

Some customers want to change this to 8-9 bar. No coffee will come out of your grouphead if the coffee grind has a resiatance greater than the setting on the overpressure relief valve. You will need the V512 pressure gauge to asses the pressure. Please note this part is not returnable. In addition, if you break something while doing this, you will need to pay for the part and shipping. If you decide to return the machine with the broken part, we will deduct the charge for the part and labor from the credit.

You can increase the amount of excess water pressure (meaning make the valve open at less than 11 bar) by bringing out the OPV and tightening the nut against the valve (like show). Or, you can decrease the amount of excess water pressure (meaning make the valve open at more than 11 bar) by bringing the OPV into the valve after you loosen the nut next to the valve.