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18.0 Fault Finding
© Baxi Heating UK Ltd 2014
Fault Finding Solutions Sections
Is there 230V at:
Is there 230V at:
Main terminals L and N
Check electrical supply
1.
NO
Main terminal fuse
Replace fuse
Replace PCB
Display
illuminated
2.
NO
PCB - X1 connector
terminals 1,2
Check wiring
3.
NO
NO
A
Pump
Replace pump
1.
YES
PCB - X3 connector terminals 3 & 4
Replace PCB
2.
NO
Change pump supply cable
YES
B
CH system pressure less than 0.5 bar
Re-pressurise system
1.
YES
Check the tap of the automatic air
vent is opened
Open the automatic air vent
2.
NO
C
1.
NO
YES
Fan connections correct at fan. PCB -
X2 connector, is 230V AC across
terminals 5 & 7
Fan jammed or faulty winding
Replace PCB
Replace fan
YES
D
If pump jammed, release
NO
NO
Replace water
pressure switch
Check connection water pressure
switch terminal
COM - NO and PCB connector
X400 terminals 3,4
YES