Immergas NIKE Mini Export, Manual

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Technical documentation Technical documentation
STNME ed 07/03
8
NIKE MINI
HYDRAULIC CIRCUIT
SECONDARY CIRCUIT
(DOMESTIC HOT WATER CIRCUIT)
- OPERATION
A d.h.w. request causes cold water to flow through the 3-way valve (1) and its subsequent movement to
operating position
(see hydraulic 3-way valve operation).
This causes the delivery pipe (M) to close with simultaneous opening of the passage towards the d.h.w.
exchanger (2).
This way, circulation is prevented in the heating system, while this does occur in the plate exchanger,
inside which the d.h.w. cold water absorbs the heat contained in the primary circuit water
(see d.h.w.
exchanger).
During this stage, the central heating function is disengaged and d.h.w. production has priority.
- DOMESTIC HOT WATER
EXCHANGER
This is a water-water exchanger consisting of 13
stainless-steel plates, one over the other, on the
surface of which the boiler circuit water and d.h.w.
cold water run in counter-current, and by means of
which heat exchange between the two liquids occurs.
It is fitted horizontally and is connected to the 3-way
valve
(primary circuit delivery), to the hot water
outlet pipe and to the return pipe of the primary
circuit by means of threaded unions with flat seal
(1).
From serial number 1511772 for NIKE Mini and
from serial number 1507922 for EOLO Mini, the
hydraulic coupling to the 3-way valve
(cold water
inlet) is of the coupling type with OR seal (2), while
previously it was obtained by means of a threaded
union with flat seal.