Potterton Promax FSB 30 HE Installation & Service Instructions Manual page 51

ELECTRICAL SUPPLY
240V at A ?
YES
240V at B ?
YES
240V at C ?
YES
240V at D ?
YES
PCB fuse OK ?
YES
Replace PCB.
© Baxi Heating UK Limited 2010
Lights
Off Off Off
No Permanent Live to
NO
boiler. Check Mains Fuse
and
System Wiring.
No Switched Live to
NO
boiler. Check System
Controls and System
Wiring.
NO
Check P/L wiring from
terminal block to PCB.
NO
Check S/L wiring from
terminal block to PCB.
Check for short circuit on
NO
condensate pump, fan &
gas valve. Replace if
shorted & replace fuse.
17.0 Fault Finding
A
B
N P/L
S/L
C
Fuse
D
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