Immergas NIKE Mini 24 Export Manual page 16

Technical Documentation Technical Documentation
Safety devices and checks for combi models.
Automatic system by-pass (3).
This device guarantees the circulation of water in the central
heating circuit even when it would be prevented by the high
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resistance of the system.
It works between the central heating delivery and return,
inserted inside the by-pass fitting (4) that connects the pump
unit (2) to the 3-way unit.
System filling unit (7).
This is a valve positioned between the boiler circuit and the
domestic cold water inlet and makes it possible to pressurise
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the heating system.
This unit is connected to the d.h.w. flow switch (6) by means
of a threaded fitting and to the pump unit (2) by means of
an O ring.
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Automatic air vent (1).
It automatically expels gaseous substances from the boiler
circuit.
It is mounted on the circulator delivery, directly on the pump
unit (2).
2
3-bar safety valve (5).
3
5
This valve prevents the safety pressure being exceeded in the
primary circuit (3 bar).
It fitted on the front of the pump unit (2) and fixed on the
outside by means of a fork.
4
When this valve triggers, water exits from the boiler return
pipe.
Expansion vessel (8). NIKE Mini 28
It compensates for variations in volume as a result of heating
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the water which also limits pressure variations.
It has a 6-litre capacity (4.5 useful litres) for the 24 model and
7.5 litres (4.5 useful litres) for the 28 model and a preload
pressure of 1.0 bar.
In the 24 model it is rectangular in shape and located on the
right-hand side of the boiler, by the side of the combustion
chamber while, in the 28 model it is circular in shape and lo-
cated at the rear of the boiler, behind the combustion chamber;
in both models a copper pipe connects the expansion vessel
to the pump unit (2).
NIKE Mini 24
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STNM ed 07/07 NIKE Mini Export
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