NECTA SPA TECHNICAL MANUAL “BRIO 250”
Service Manual: Brio 250
Edition 02-2002
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AIR-BREAK FRONT VIEW WITH DOOR OPEN
Operating conditions at first start-up:
When the machine is started, a microswitch connected to the float
indicates the absence of water to the SW, from the control board a signal
is sent to relay K16, which activates the water inlet solenoid valve.
Water is delivered to the air-break flowing through filter “F”, thus
eliminating any foreign matter present in the water (sand, calcium
particles, etc.). Upon reaching the maximum level the microswitch is
triggered indicating the situation to the SW, then the relay and the
solenoid valve are de-energised.
In the event of water not reaching the maximum level within a set time
(for example because of water interruption from the mains), the SW
disables all functions and sets the vending machine in “Water Failure”
condition.
Stand-by operating condition
With the air-break full, when a selection is made a solenoid valve is
activated (2-way or 3-way according to the type of selection) and at the
time the pump draws water from the air-break and sends it to the boiler
flowing through the volumetric counter, determining the exact amount.
When the water falls below a set level, the microswitch is activated
starting the re-filling cycle.
NOTE:
The above cycle applies to the espresso version only, as in the
instant version the air-break is incorporated in the boiler and there is no
pump, since water for a selection is dispensed by 2-way gravity solenoid
valves, the dose computation is by timing according to the valve rated
flow (normally between 10 and 12 cc/sec).
Level indicator
microswitch
AIR-BREAK: VIEW FROM REAR SIDE
WITHOUT PROTECTIVE CASING
AND COFFEE CONTAINER
Wiring for signals
to microswitch and
air-break
Overflow
drain tube
Water inlet
filter “F”
Level indicator
microswitch
