espresso coffee machine - technician instructions
18
- english
R
4. Distribution machine BOILER and EXCHANGERS
The boiler is constructed in copper sheet metal
(1)
, to which the heat exchangers are assembled which in turn are connected to the delivery
group. Water for coffee delivery is taken directly from the heat exchanger. During delivery, cold water is sent to the inside of the exchanger
by means of the motor pump. Inside the heat exchanger, cold water and the pre-existing hot water are mixed, thus obtaining optimal water
temperature for coffee infusion.
5. COFFEE DELIVERY GROUPS
The delivery group and the heat exchanger are the fundamental components in obtaining
espresso coffee. Specifically, the purpose of the group is to dispense the coffee.
4.1 ELECTRIC HEATING
The water is heated in the boiler by means of an electrical heating element immerged in
the water
(2)
.
4.2 GAS HEATING
Gas heating is obtained by supplying the flame of the burner located under the
boiler.
4.3 COMBINED GAS + ELECTRIC HEATING
In machines equipped with both systems, it is possible to combine the heating types.
5.1 LEVER GROUP
The lever group uses the boiler pressure and water. This system does not require heat
exchangers.
When the lever
(1)
is lowered, the spring
(2)
inside the group is compressed: the piston
(3)
raises, allowing water to enter the pre-infusion jacket. When the lever is released,
the piston compresses the water to 8-10 bar, allowing delivery of espresso coffee. The
non-return ball valve
(4)
keeps water from flowing back into the boiler
(5)
.
2
1
3
2
4
5
1
Phase 1
Lowering the lever.
Phase 3
Release of lever
and delivery of
the coffee.
ATTENTION
Do not replace the heating element with a more powerful one. Before making any modi
fi
cations, contact the manufacturer.
Phase 2
Pre-infusion for 3÷5
seconds.
