15.0
Fault Finding
55
© Baxi Heating UK Limited 2005
Rectify wiring.
NO
YES
Unplug
3-way PCB connector
& unplug fan. Is there
continuity from K to L &
from M to N ?
NO
Unplug
the smaller of the
6-way PCB connectors. Is there
continuity from O to P & from Q
to T & from
S to R ?
Replace fan.
FAN
Rectify wiring.
YES
K
M
O
S
Q
N
L
R
Viewed from
Wire Entry end
P
T
Fan
Connection
PCB
Connection
Fan
Connection
PCB
Connection
DHW FLOW SWITCH
Replace PCB.
Unplug
5-way connector
from PCB. With all DHW taps
off is there continuity
across W ?
NO
Is
DHW flow switch
blocked ?
Unblock DHW flow
switch.
NO
Replace DHW flow
switch.
YES
YES
Viewed from
Wire Entry end
W
Off
Flash
Flash
On
ON
LED
Lights
NOTE: The fan is supplied with 325 Vdc.
Fan Fault Finding should only be carried out after
the boiler has been electrically isolated.
On
On
Flash
Flash
ON
LED
Lights