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Alpha CD12S/20S/28S - Wiring Diagrams
9.1 ILLUSTRATED WIRING DIAGRAM
9 WIRING DIAGRAMS
Br
- Brown
Bk
- Black
Bl
- Blue
R
- Red
Or
- Orange
G
- Green
NOTE:
TO CONNECT EXTERNAL CONTROL
REMOVE LINK FROM TERMINALS 1 & 2
AND CONNECT 230/240 V SWITCHED LIVE TO
TERMINAL1.
A FROST THERMOSTAT IS INCORPORATED
WITHIN THE MAIN PCB
G
G/Y
Or
Or
Bl Br
Heat Exchanger
Thermal Fuse
W/Bl
Bk
Flue Temperature
Sensor
Y
Y
S3
S1
S2
Main
PCB
CH CAP
MAX CAP
Br
Bl
X7
Bl
P
Bk
Bk
W
R
Gy
Br
Bk
R
Bl
Br
Gy W
R
Or
Y
R
Or
Y
Gy
G
W/Bl
W/Bl
Pk
Pk
Br Bk Bl W P
Fuse
F2A
Link
Supply
230/240V-50Hz Fused at 3A
2
1
N
L
Pump
Br
Bl
Gas Valve
Overheat
Thermostat
X3
1 2
X8
3
2 1
X4
1
2 3 4
X13
4
5
3
2 1
X6
4
3
2 1
X12
4
5
3 2
1
X15
4
6
5
2 3
1
X9
4
6
9
5
8
2 3
7
10
1
X11
4
6
5
8
2 3
7
1
W Gy
5
4
3
2
1
Br
Bk Bl
(Optional) 2 Channel Clock
2
1
Spark
Generator
Transformer
Pk
P
Pk
G
240
V
a
c
24
V
a
c
CH SET
DHW SET
Primary
Pressure
Switch
Or
Or
NO
COM
Primary
Temperature
Sensor
R
R
G/Y - Green/Yellow
W
- White
Gy
- Grey
Pk
- Pink
P
- Purple
W/Bl - White/Blue
Br
Bk
Bl
W
P
Fan
Flame
Sensing
Electrode
4
3
Ignition
Electrodes
Green LED
Yellow LED
Red LED
Red LED
Fuse F1
315 mAT max
250 V
Fuse F2 and F3
2.5 AF
250 V
F1
F2
F3
Summary of Contents for CD12S
Page 43: ...43 Alpha CD12S 20S 28S...