53
Set the operating switch
(or programmer)
to OFF, and turn both
control knobs
anti-clockwise to OFF.
Does the pump continue
to run for approx.
5 minutes?
When the pump
has stopped,
turn on fully a
hot water tap.
Does the demand
indicator
illuminate?
Does the pump run?
END OF
DOMESTIC HOT
WATER TEST
Whether the pump
stops immediately
or continues
indefinitely the
control board will
be at fault.
Replace control board
Replace demand
indicator
Replace the
control board
Replace the
flow switch
Replace the
control board
Replace the
control board
Is there 230V at
pin 1 of
terminal
X1
?
(Blue wire)
Is there 230V at
pin 3 of
terminal
X1
?
(Brown wire)
Is there approx. 90V
at pin 5 of terminal
X3
? (DEM)
Note:
Lamp is not
driven directly by
mains voltage
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
FAILURE A
T
POINT G
FAILURE A
T
POINT H
FAILURE A
T
POINT I