gledhill BoilerMate CP 120 Design, Installation & Servicing Instructions page 24

SERVICING
Normal - standby state
Indicate system status
Press S2
Sensor temperature
reading
Press S2
Control set-point
reading
Press S2
Fault code indicator
lock outs
Press S2
Fault code indicator
block outs
2 DIGIT ACB BOARD DISPLAY FLOW CHART
Appliance Control Board
The appliance control board (shown opposite) has a 2 digit display and 2 push buttons
which are used to check the status of the appliance, check and set its identity and
interrogate it for the current faults and the fault history.
The 2 digit display is controlled by 2 buttons S1 and S2. The fl ow chart of display
modes is shown above. Generally, each press of button S2 cycles the display from top
to bottom and each press of button S1 cycles the display functions from left to right.
The button S2 is also used to reset the appliance i.e. clear the lockout errors and reset
the appliance. (Note: Appliance resetting can also be carried out using the push
button on the front panel)
If S1 is fl ashing on its own, the system is running normal.
If a sensor error is detected one of the following three error codes fl ash alternately
with the sensor number instead of the temperature
E1 Open circuit
E2 Short circuit
E3 Temperature greater than 99°C
A code of FF indicates the fault location is empty.
FAULT FINDING
S2 S1
Press Press Press
S1 S1 S1
Press Press Press
S1 S1 S1
Press Press Press
S1 S1 S1
Press Press Press
S1 S1 S1
Press
S1
Press
S1
Press
S1
Press
S1
APPLIANCE CONTROL BOARD (A.C.B)
Display in Normal (Standby) Mode
In the standard/normal mode the 2 digit display
indicates the status of the appliance inputs
and outputs by switching on the appropriate
segments of the display.
Page 24
2 digit
display
2 push
buttons
S2 S1
Main
processor