Immergas EOLO Mini - Secondary circuit (D.h.w. Circuit)

11
STEMkW Special ed 01/08 EOLO Mini kW Special
Technical Documentation
Technical Documentation
Operation.
When domestic hot water is drawn cold water ows inside
the d.h.w. ow switch (1) which closes the electrical contact
coupled to it (see the electrical circuit).
As a result, the integrated P.C.B. starts the d.h.w. priority phase
that ignites the burner and, if there’s an ongoing central heating
request, switches the 3-way diverter valve (2) moving it into the
working position (see operation of the hydraulic 3-way valve).
is causes the ow pipe (M) to close and simultaneously the
passage opens to the d.h.w. exchanger (3).
In this way circulation in the central heating system is preven-
ted while it is allowed in the plate exchanger, inside which the
domestic cold water absorbs the heat from the primary circuit
water (see d.h.w. exchanger).
So in this phase, central heating is o, domestic hot water
having priority.
e water/water heat exchange occurs inside the d.h.w. exchan-
ger (3) which is secured to the d.h.w. inlet (1) and outlet (2)
body with screws.
e top of the body on the left allows cold domestic water to
enter, while at the bottom it allows primary circuit return.
In the same way, the top part of the body on the right allows
the outlet of domestic hot water while at the bottom it allows
primary circuit ow.
Secondary circuit (D.h.w. Circuit).
Cold water
inlet
1
3
2
Primary circuit
ow
Primary
circuit return
D.h.w. outlet
D.h.w. outlet