NECTA SPA TECHNICAL MANUAL “COLIBRÌ”
Service Manual: Colibrì Edition 02-2002 11 /25
3 - AIR-BREAK / BOILERS
Its 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 a factory set
minimum and maximum (it is very important not to replace the microswitch with 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 that anyway 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
Air-break level control microswitch
Air-break
Overflow tube
Water inlet solenoid tube
Mains water inlet solenoid valve
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