Biasi GARDA M90F.24S Service Manual page 21

To disconnect the connectors J1, J3, J7, J15, J16
and (5, 1, 8, 14 and 6 in Fig. 28) delicately flex
the hook present on one side of each socket.
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
arrow in Fig. 37.
Fig. 37
4 Unscrew the four screws that hold the Electronic
starting control 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 starting control
p.c.b. following the removal procedures in the re-
verse order.
Important
When re---assembling the Electronic starting control
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. 38) reaches the potentio-
meter edge. It is not necessary to force them in
the knob.
Electronic starting control p.c.b.
9 While tightening the screws that fix the Electronic
starting control p.c.b. on the control panel, keep
the p.c.b. towards the control panel fascia mak-
ing sure of the contact between the boiler reset
button B and the tab C (Fig. 38).
A
A
Fig. 38
Attention
After installing the Electronic starting control p.c.b. :
10 Make sure the c.h. (
perature adjustment knobs can move freely for
the complete range.
If not, remove the spindle again as described at
step 3, turn the knob half a turn and re---insert the
spindle.
11 Operate the boiler and close the gas inlet cock so
that the boiler goes into the safety lock ---out state.
Verify the correct operation of the boiler reset but-
ton by pressing and releasing it.
Warning: After cleaning or replacement as
detailed above refer to section Combustion
analysis check in the chapter Maintenance of
the installation instructions manual.
B
C
) and d.h.w. ( ) tem-
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