Setting Jumpers; Ignition Gas Pressure Adjustment; Max C.h. Power Adjustment; Checks - Biasi RIVA COMPACT M90E.24S Service Manual

After any adjustment operation the selector has to be
brought back to the normal position (ON).
Selector 2
f
This selects the boiler functions on the basis of the type
of gas used.
It allows the selection of the maximum supply current
given to the modulator device.
To set selector 2 correctly follow the table in Fig. 32.
Gas supply Position of selector
Natural gas On
L.P .G. Off
Fig. 32
Selector 3
f
This forces the functioning of the boiler in order to allow
the optimal gas pressure at the burner to be adjusted
during the ignition phase.
The adjustment (see section 9.7) is done by means of
the potentiometer "11" marked "ACC" (Fig. 28 on page
18).
After the adjustment operations bring the selector back
to the normal position (ON).
gas pressure calibration
Fig. 33
Selector 4
f
This allows you to select the minimum time that must
pass between two ignitions of the burner in c.h. func-
tion.
30 sec.
Fig. 34
9.6

Setting jumpers

Two setting jumpers are fitted on the Electronic control
p.c.b.
Refer to Fig. 35 for the position of the jumpers.
The numbers refer to the marking printed on the circuit
board.
1 2 3 4 5 6 7 8 9
Fig. 35
Approx. Max current
through the modu-
lator device
120 mA
165 mA
ON (1)
OFF (0)
Normal
ON (1)
OFF (0)
3 min.
9.7

Ignition gas pressure adjustment

By using the device "11" (Fig. 28) marked "ACC." on
the Electronic control p.c.b., it is possible to adjust the
gas pressure at the injectors in the ignition phase.
This pressure is maintained at the injectors until ignition
occurs (ionization signal from the full sequence ignition
device).
To carry out the adjustment move the function selector
3 to the OFF position (Fig. 33) and use the adjustment
device "11" (ACC).
Adjust the gas pressure at the injectors to the value indi-
cated in the tables of the User/Installation manual
(Technical information section, Gas pressures at the
burner table).
By rotating the device clockwise the pressure in-
creases.
Check the regular ignition of the burner by turning the
boiler on and off repeatedly.
After the adjustment operations bring the selector 3
back to the normal position (ON).
9.8

Max c.h. power adjustment

By using device 12 (Fig. 28) marked "RISC." on the
Electronic control p.c.b., you can limit the maximum
useful output delivered during the c.h. operating mode.
This adjustment does not influence the maximum use-
ful output delivered during the d.h.w. operating mode.
By rotating the device clockwise the pressure in-
creases.
9.9

Checks

Check that the fuse is complete
n
If the Electronic control p.c.b. does not supply any de-
vice (pump, fan, etc.) check that the fuse 14 (Fig. 28) is
complete.
If the fuse has blown replace it with one that has the
same characteristics after having identified the reason
for failure.
Check the setting jumpers position
n
Two setting jumpers must be fitted on the Electronic
control p.c.b. as shown in Fig. 35 and NO TAG.
9.10

Removal of the electronic control p.c.b

Warning: isolate the boiler from the mains
electricity supply before removing any
covering or component.
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 p.c.b..
To disconnect the connectors J1, J2 and J3 (13,
2 and 1 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. 36.
Electronic control p.c.b.
21