Coffee Delivery Groups; Electronic Control Unit (Version Evd); Volumetric Dosing (Version Evd) - Wega Mininova Use And Maintenance Manual For The Technician

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Coffee delivery groups

The delivery group and the heat exchanger are
the fundamental components in obtaining espresso
coffee,in particular, the function of the group is the
coffee erogation.
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 the 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 (1) 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.
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not working
coffee
delivery
in erogation
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5
4
w a t e r
inlet
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Electronic control unit (version EVD)

The electronic control unit is installed on the machines
with volumetric dosing. Its function is to
manage electronically the dose of coffee
through the passage of the water in to
the dispenser and control the loading of
the entry of the water in the boiler. Some
versions of control unit are designer for the
connection of systems of accounting for
payments through a special interface device.
Some units include a button lithium battery.
i
When it needs replacing, disconnect the machine
from the power outlet and open the central unit
placed inside the equipment.
Dispose the battery in compliance with the
collection regulations of the country of use.
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Volumetric dosing (version EVD)

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The volumetric dosing device, installed on electronic
version EVD, serves the purpose of measuring the
quantity of water sent to the group of espresso delivery.
The dosing device generates an electrical impulse
which is sent to the electronic control unit. This impulse
is read by the control unit and memorized during the
programming of the dose
The flashing of the LED (1) indicates that the electrical
impulse has been sent from the dosing device to the
control unit.
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1