Fault Finding And Diagnosis; Internal Wiring Diagram - Worcester 27i System Compact Installation, Commissioning And Servicing Instructions

FAULT FINDING AND DIAGNOSIS

7 FAULT FINDING AND DIAGNOSIS
7.1

INTERNAL WIRING DIAGRAM

FAN
FLOW
N L
GAS
VALVE
SAFETY
SOLENOID
Red
G/Y
Blue SAFETY
Orange
SOLENOID
EMS
X2
CH TEMPERATURE
CONTROL
LCD DISPLAY
X7
13
54
Fan wiring:
Live = Brown
Neutral = Blue
NTC
RETURN
NTC
PUMP SUPPLY
230V
FR FS LR LR
OUT
N L N L N L
X16
Worcester 24V controls point
HCM (at rear of PCB)
X6 X5
13 1
1 13 1
SPARK
ELECTRODES
FLAME SENSE
ELECTRODE
MAX SAFETY NTC
FLAME SENSE
GROUND
PUMP
PUMP CONTROL
Fuse, slow
230V
F 5A H 230 V
IN
N L N L
EMS BUS point
X3 X11 X4
Greenstar i System Compact - 6 720 807 726 (2013/05)
PRE WIRED LINK
FLUE
STAT
DIVERTER
VALVE PLUG
(NOT USED)
DHW TEMPERATURE
CONTROL
DIAGNOSTIC
INPUT
X12
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