Potterton Promax SL range Installation & Service Instructions Manual page 55

ELECTRICAL SUPPLY
240V at A ?
YES
240V at B ?
YES
PCB fuse OK ?
YES
Replace PCB.
© Baxi Heating UK Ltd 2014
Lights
Off Off Off
No Switched Live to
NO
boiler. Check Systems
Controls and System
Wiring.
NO
Check wiring from
terminal block to PCB.
Check for shorts on
NO
pump, fan & gas valve.
Replace if shorted &
replace fuse.
17.0
ON
Fault Finding
A
N
L
B
Fuse
Optional
Pump
Live
55