Rancilio S27 - Owners Diary
Last Updated: 27.03.2025
General Information
Measurements: 380 x 465 x 515 mm (WxHxD)
Power draw: 230V, 50Hz, 2050W
Boiler capacity: 3.9L
Weight: 35 kg
Volumetrics
Setting the volumetrics
Press and hold the right most button (the one which doesn’t picture a cup) until water stops flowing out of the group head, and it starts blinking to enter programming mode
Put in your portafilter
Press the button you want to program
Press the rightmost button again to stop the flow and store the value
Press the rightmost button again to exit programming mode
Standard Deviation
When using the volumetrics to pull a 18g in / 36g out shot of espresso, I observed a standard deviation of just 2.02g, which is pretty good.
Grounding of the Flowmeter
I ran into a small issue where the Flowmeter wouldn’t report flow in an understandable and reproducible way.
This happened because some scaling had occurred on the flowmeter itself due to a brittle O-ring. Once I replaced it and sanded down the Flowmeter, so the grounding wire made contact to ground again, the flowmeter works flawlessly once more.
Hardware Exploration
Pinout of the Keypad
| Pin | Name | Comment |
|---|---|---|
| 1 | GND Continous LED | |
| 2 | GND Dose 4 LED | |
| 3 | GND Dose 3 LED | |
| 4 | GND Dose 2 LED | |
| 5 | GND Dose 1 LED | |
| 6 | Button Dose 3 1 | |
| 7 | Button Dose 3 2 | |
| 8 | Button Dose 2 | |
| 9 | Button Dose 1 | |
| 10 | Button Dose 4 | |
| 11 | Button Continuous | |
| 12 | Common Anode for the LEDs | +3.3V / +5V => Needs to be checked |
Doses are counted from the left of the keypad to the right