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3.2 PCB
The main board (PCB) of the boiler is protected by a plastic cover that must be removed to access to the micro-
switches on the board. The circuits of the electronic board are protected by a coating: this particular treatment protects
it from stray currents, humidity, dust and tampering, guaranteeing a longer component longevity.
For safety reasons and in order not to damage the boiler itself, every time you work on the PCB it
is necessary to disconnect the plug from the electrical outlet: the boiler switch off via the ON/OFF
button of the control is not sufficient.
At the top of the PCB, on the left, there are two banks (SW1 and SW2) of eight microswitches each; on the right, there
are three leds of different colors (red, green and yellow).
meaning of microswitches SW1
Some boiler settings can be changed by changing the sequence of the micro switches on the SW1 bank according to
the following table:
Nr.
Bank SW1
1 OFF
NG
(G20)
ON
Prop.
(G31)
OFF
Air-
prop.
(G230)
ON
LPG
(G30)
OFF
Not in
use
ON
Not in
use
OFF
Not in
use
ON
Not in
use
2 OFF
OFF
ON
ON
OFF
OFF
ON
ON
3 OFF
OFF
OFF
OFF
ON
ON
ON
ON
4 OFF
Model:
REB-KBI2424FF
ON
Model:
REB-KBI2929FF
OFF
Not in use
ON
Model:
REB-KBI3535FF
5 OFF
OFF
ON
ON
6 OFF
Low altitude installation ( to 900m asl)
ON
High altitude installation ( above 900m asl)
7 OFF
Normal operation mode
ON
Microswitch setting change enabled
8 OFF
ON
For safety reasons, the electronic board accepts the changes of the microswitches only if the
microswitches no. seven and eight (ON) are enabled in advance; otherwise, the board ignores any
change of the microswitches, interpreting their displacement as accidental, involuntary, and the
boiler goes to lock, showing the error code 20.
At the end of the changes it is necessary to restore the microswitches no. seven and eight to OFF.
Led meaning
The LEDs of the PCB help as a visual guide during the changes to the microswitches of the bank SW1.
The ignition and the flashing have a precise meaning:
Red led = gas type
Green led = model
Yellow led = altitude
One blink
NG (G20)
REB-KBI2424FF
Low altitude setting
Two blinks
Propane (G31)
REB-KBI2929FF
High altitude setting
Three blinks
Air/propane (G230)
Four blinks
LPG (G30)
REB-KBI3535FF
IMPORTANT
Red led (1), green (2), yellow(3)
Dip switches SW1 and SW2
IMPORTANT