User manual for NERO / NERO INSTANT
Page 20
Version 3.2 / December 2017
It is STRICTlY PROHIBITED to set the cam to positions 7 or higher!!!
The recommended settings for the cam are positions 3 or 4. This means a dose of 6.5-7.5 grams per
portion (per drink).
The weight of the ground coffee inside the dosing apparatus depends on the quality of grinding and type
of coffee.
After each re-setting of dosing apparatus, please weigh the amount of ground coffee according to the
current manual.
Depending on the weight of the coffee, you might need to regulate (adjust) the volume of espresso
group’s chamber.
Figure 24
If the level of grinding will be too low (very small particles), the coffee grinder will not be able to ground
sufficient amount of coffee, which would lead to “Grinder” error and will block the dispensing of coffee.
In such case you should increase the level of grinding. For the purpose you must loosen the upper disk
by turning it counter clockwise.
If the particle size is large the coffee will be less concentrated (less saturated). The time of working of
coffee grinder will be around 3-4 seconds. The thickness of output jet will be 3-4mm. in this case you can
also cause the leaking of the coffee group, because very large particles of coffee damage the gasket of
the piston. In such cases you should decrease the particle size – turn the upper disk clockwise.
The optimum time of grinder functioning is: 5-6 seconds if coffee dosage is set to position 3 and 6-7
seconds if the coffee dosage is set to position 4 (see the next section).
The ground coffee is fed into the dosing apparatus, which ac-
cumulates ground coffee up to a certain level. When the level is
reached the electromagnetic valve opens and the accumulated
dose of coffee is sent to the espresso group.
The dosing apparatus helps you set the required amount of cof-
fee for the espresso group according to the desired drink.
The volume of coffee is regulated with the help of the dosing
apparatus’s cam (see figure 23 position 2 and figure 24). The po
-
sitions can be from
1 to 6 (MAXIMUM)
. At the same time it is pro-
hibited to set the cam to positions 5 or 6 without increasing the
volume of the boiling chamber (see further)!
THIS CAN DAMAGE
THE ESPRESSO GROUP!!!