Main Circuit Flow Switch; Function - Savio GAIA 424 S Service Manual

13

Main circuit flow switch

13.1

Function

The main circuit flow switch (A in fig. 62) is a device that
controls the speed of water that crosses the main heat
exchanger.
A
fig. 62
This device controls the regular functioning of the
pump, the presence of water in the primary circuit of the
boiler and the absence of obstructions of the main heat
exchanger during the c/h function as well as during the
d.h.w. function.
As a consequence of any one of these causes the main
circuit flow switch cuts---off an electric circuit by means
of a microswitch (B in fig. 64) installed on it.
The main circuit flow switch is connected to the elec-
tronic control circuit and its intervention prevents or
stops the burner ignition cycle but does not send the
boiler in the lock state.
13.2
Checks
Warning: isolate the boiler from the mains
electricity supply before removing any
covering or component.
General check
n
It is possible to verify the general operation of the switch
by measuring the voltage between its leads during the
operation on c/h or d.h.w.
Warning: isolate the boiler from the mains
electricity supply before removing any
covering or component.
1 Switch off the boiler and open the control panel.
2 Connect a meter, set for alternating voltage
(230V) measurement, to the points indicated in
fig. 63.
3 Switch the boiler on
age by matching the readings with the values
indicated in the section 3.3.
position and verify the volt-
fig. 63
Mechanical function
n
1 Remove the front panel of the case and lower the
control panel as described in the section 2.2 of
this manual.
2 Remove the fork C that holds the main circuit flow
switch B (fig. 64).
fig. 64
3 Start and stop the boiler in c/h operation (time
switch and external controls must call for heat)
and verify the position of the shaftD referring to
fig. 65
fig. 65
V~
B
C
Boiler OFF
D
Boiler ON
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