Checks; Removal Of The Electronic Control P.c.b - Biasi Parva HE M96.24SM/P Service Manual

9 Turn the boiler OFF and ON positioning the func-
tion selector knob A as indicated in Fig. 46
E B
Fig. 46
10 Keep pressed the reset button C for about 10 sec-
onds until the lock ---out signal lamp D blinks.
11 Press the reset button C repeatedly (4 times) until
the lamps E give the indication as in Fig. 47 (igni-
tion pressure adjustment mode).
Where:
Fig. 47
12 Turn the knob B to the minimum (fully counter-
clockwise) and then on the position correspon-
ding to the position obtained on step 7.
By turning the knob B, the lock ---out signal lamp
D blinks quickly (2 per second) indicating that the
setting has changed and must be memorised.
13 To memorize the setting keep pressed the reset
button C for about 5 seconds until the lights E
briefly blinks simultaneously.
14 To reset the boiler to the normal operation turn it
OFF and ON by the function selector knob A
checking the ignition pressure and that the
burner lights up uniformly. In any case, the boiler
automatically resets to its normal operation after
10 minutes.
10.9

Checks

Check that the fuses are complete
n
If the Electronic control/ignition p.c.b. does not supply
any device (pump, fan, etc.) check that the fuses 11
(Fig. 29) are complete.
If a fuse has blown replace it with one that has the same
characteristics after having identified the reason for fail-
ure.
Lock sequence
n
Start the boiler until the burner is ignited.
With the burner firing, interrupt the gas supply. The
Electronic control/ignition p.c.b. must carry out three
complete ignition cycles and then, after about 3 min-
utes, goes to lock ---out state.
By turning the boiler on and off by means of the function
switch the device must not unlock and the burner must
not turn on.
A
C D
Lamp OFF
Lamp ON
Electronic control/ignition p.c.b.
Fan functioning device
n
With the boiler operating and the burner on, open the
negative pressure test point of the Venturi device.
At the moment of opening the burner must turn off.
10.10

Removal of the electronic control p.c.b

Warning: isolate the boiler from the mains
electricity supply before removing any
covering or component.
When replacing the Electronic control/ignition
p.c.b. it is advisable to go through the setting modes
of the boiler
1 Gain access to the parts located inside the con-
trol panel as explained in the section 2.3 of this
manual.
2 Remove all the wiring connected to the Electronic
control/ignition p.c.b..
To disconnect the connectors x1, x6 and x7 (1, 2
and 3 in Fig. 29) delicately flex the hook present
on one side of each socket.
To disconnet the connectors x4 and x2 (4 and 5
in Fig. 29) press delicately the hook present on
one side of each connector.
3 Remove the spindles of the c.h. and d.h.w. tem-
perature adjustment knobs by delicately pulling
them with pliers in the direction shown by the ar-
rows in Fig. 48.
Fig. 48
4 Unscrew the four screws that hold the Electronic
control/ignition p.c.b. on to the control panel.
5 Remove it by lifting its rear edge and freeing it
from any of the wiring.
6 Re---assemble the Electronic control/ignition
p.c.b. following the removal procedures in the re-
verse order.
Important
When re---assembling the Electronic control/ignition
p.c.b.:
7 Fit the p.c.b. into the control panel by first insert-
ing the front lower edge under the control knob
shafts. Lower the rear edge and ensure that no
wiring is trapped beneath.
8 Insert the spindles in the control panel knobs un-
till the notch A (Fig. 49) reaches the potentio-
meter edge. It is not necessary to force them in
the knob.
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