NECTA SPA TECHNICAL MANUAL “BRIO 250”
Service Manual: Brio 250
Edition 02-2002
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3 - AIR-BREAK / BOILERS
It is the same functional unit used in the Venezia and Spazio vending machines, therefore with established
characteristics and reliability.
It is a functional unit that permits various functions:
Its main function is to keep the water level constant and to signal a water flow interruption from the mains; in the
event of such water failure the current selection can be completed.
In addition, it serves the purpose of holding a reservoir of water at normal atmospheric pressure, so that the
pump can draw the correct water dose for the selection and deliver it to the Espresso boiler without changes in
pressure that may affect the volumetric counter reading.
The dose is measured by means of the volumetric counter.
The water level is ensured by a float that triggers a microswitch, keeping the level between the factory set
minimum and maximum (it is very important not to replace the microswitch with another one of different
mechanical characteristics, as a variety of malfunctions may occur).
Furthermore, in the event of failure to the maximum level microswitch, an overflow hole allows the water to be
conveyed through a tube and to the safety device fitted on the water inlet solenoid valve, thus causing its
mechanical lock (such safety device is triggered also in the event of a power failure).
The air-break also causes a signal to be sent to the machine control board necessary for the initial installation and
for filling with water. This air break operation initially needs to be done manually.
If upon switching the machine on, the float does not trigger the maximum level microswitch within a set time
(e.g. 60 sec) the vending machine locks due to a water failure.
Back view without protective casing
DETAIL OF AIR-BREAK SYSTEM INCORPORATED IN THE OPEN-TOP BOILER (INSTANT MODEL
)
Float
REAR VIEW WITHOUT CASING - ESPRESSO VERSION WITH SEPARATE AIR–BREAK
Air-break
Float microswitch for
level indicator
Overflow drain
tube
Pressure boiler
Water
inlet tube
Actuation rod for
float microswitch
Open top
boiler
