R
espresso coffee machine - instructions for technician
5.2 DELIVERY GROUP
In this system, the delivery group (1) is heated by a thermosiphon circuit (2) connected to the heat exchanger (3). The same water is used
for coffee delivery, thus ensuring the same temperature for all coffee servings.
• activation of the solenoid valve and of the pump allow cold water to enter the exchanger (3) through the injector (4).
• from the exchanger (3) the boiler water is carried to the group (4) for delivery;
• the pump allows the increase of the pressure of the water flow up to 8-9 bar for delivery.
The injector (4) and the flow reducer (5) are important components for the operation of the delivery group.
To increase the coffee extraction temperature, remove the flow reducer (5) or replace it with one of a greater diameter. To decrease the
temperature, replace it with one of a smaller diameter.
If necessary, the exchangers can be replaced by removing the flange and disconnecting the relative pipes of the hydraulic circuit. These ope-
rations should be carried out after the machine has been switched down and has cooled off. Always replace the seals.
5
2
delivery
coffee
1
3
4
3
inlet
at rest
in delivery
water
5.3 DELIVERY DELIVERY
This group functions with a double-outlet type exchanger.
The delivery is controlled with a manual valve system. The opening and
the closing of the valves for the passage of the water is operated by
a lever placed beside the group which, in turn, operates a cam inside
the group, opening and closing the water.
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English