The unit is preset to dispense 1.2 Fl oz (35 ml) when making a single espresso. To change the quantity of water you can do this by using the My Coffee setting.
The way to do this:
1) First choose the drink you want to reprogram (Espresso, Americano, Coffee)
2) Press the My coffee button to enter into the programming mode, it will start to flash
3) While is flashing you must press the OK button to start the brewing process
4) Allow the unit to dispense the amount you desired and when that has been reach you press the ok button again to end
4a) If you are changing the Americano setting, the hot water will start to dispense then when the amount you desired has been reached press the OK button again to end
5) Press the My Coffee button to memorize the new setting
Please follow this video for a step by step process:
