Perhaps the most accurate location of all is inside the brew head. In heat mode and standby mode, hot water flow to the upper part of the boiler, so measuring pressure in the upper position seems more accurate to me. In the steam mode, water in the boiler turn into steam and gets hotter in the top of the boiler, it is reasonable than that locating the gauge outlet in the steam path would give more precise and quicker response readings, especially when steaming. But measurements done by others suggested it is not consistent and that there are differences between readings depends on location. So connecting the gauge to points 1, 2, 3, 4 or 5 should result the same.

Looking at the above Silvia water path that I made, it shows that since all the above locations are connected, pressure theoretically should be the same in each.

I made the flow test after I completed the pressure gauge mod and when gauge showed 9 Bar, I got 320cc which is the value when looking at the Max.

Some sites suggest only 260cc based on the medium graph which I believe is a mistake. This technique is based on Ulka pump’s specification graph which draws the typical flow rate vs. In 1 minute of brewing operation (with blind basket) you should get 320cc of water if pressure is set to 9 Bar. Tip: If you don’t have a gauge and want to measure your Silvia pressure, you can do it easily (though not accurately) by measuring the flow rate from the OPV pipe while using a blind basket. 5 on page 8 and section 8.7 on page 35 of Silvia manual. Tip: For the way to adjust the OPV, follow Fig. On a daily base, the pressure gauge serves mainly as an indicator that tells you if everything is OK. If you find your Silvia pressure is anything but 9 Bar, you can adjust the OPV to correct. Pressure reading helps to understand if pressure is correct for brewing. It is not meant for daily use, only for calibration in case it is out of normal. Silvia V3 has an OPV (Over Pressure Valve) that controls pressure.

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