Technical documentation
Technical documentation
STEM@ ed 06/01
7
EOLO MAIOR @
- SAFETY DEVICES AND CONTROLS
Automatic system by-pass
(1)
(combined versions only)
This ensures circulation in the primary circuit even
when this is prevented by the high resistance of the
system.
It operates between the supply and return of the
primary circuit and is accessible after the three-way
enbloc in brass into the two sections of which it is
made.
It can be disengaged (
closed
) by turning the bypass
disengagement screw (2) clockwise.
In the case of models for central heating only (S), the
bypass is optional and is fitted between the system
delivery and return connection pipes.
System filling unit (5)
This stopcock is positioned between the boiler circuit
and the cold water inlet and makes it possible to
pressurise the heating system.
It is housed in the lower part of the enbloc to which it
is screwed up.
In the case of version
27
only, downstream of the
stopcock, an one way valve is fitted (6)
(disconnector)
that prevents accidental flow of water
from the primary circuit to the water network
(d.h.w.
circuit).
System water pressure switch (3)
This reads the pressure inside the primary circuit.
It is housed in the enbloc and is coupled to a
microswitch that prevents boiler operation when the
read pressure is below 0.3 bar.
This way overheating of the main exchanger is
prevented.
3-bar safety valve (4)
This prevents safety pressure being exceeded in the
circuit (3 bar).
It is fastened in the front part of the enbloc by means
of a socket-head screw.
When this engages, water exits from the delivery pipe.
Automatic air vent (7)
For automatically expelling any gaseous substances in
the circuit.
Fitted on the water side of the expansion vessel.
Expansion vessel (8)
Compensates changes in volume following heating of
water and permits reducing pressure changes.
This is positioned in the rear of the appliance and is
connected to the pump by means of a coupling pipe (9).
It has a pre-load pressure of 0.8 bar and a capacity of 8
l in versions 21-24 and 10 l in version 27.
