15.0
Fault Finding
44
No Switched Live to
boiler. Check Systems
Controls and System
Wiring.
240V at B ?
Check wiring from
terminal block to PCB.
Check for shorts on
pump, fan & gas valve.
Replace if shorted &
replace fuse.
YES
NO
Replace PCB.
YES
YES
NO
NO
ELECTRICAL SUPPLY
240V at A ?
PCB fuse OK ?
B
Fuse
A
Optional
Pump
Live
N
L
Off
Off
Off
ON
Lights
Summary of Contents for System 100 HE Plus
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