Technical data

17
• Close isolating valves on flow and return connec-
tions.
It is not necessary to drain entire heating circuit to
carry out this work.
• Gain access to pump connection as described
in 'To replace main PCB'.
• Pull off pump connector and earth lead.
• Pull out retaining clip from telescopic pump out-
let connection and slide connection upwards to
release from pump.
• Undo and remove two fixing screws and remove
pump retaining bracket from front of pump.
• Grasp pump body, lift upward to disengage from
reversing valve and turn pump to right. Remove
pump by pulling forward and over reversing valve
assembly.
• Discard old pump inlet 'O' ring.
• Apply silicone grease to new 'O' ring supplied,
and fit onto inlet connection on replacement
pump.
• Fit replacement pump in reverse order to re-
moval.
Note: Apply silicone grease to pump outlet con-
nection 'O' ring before assembly.
• Refit pump electrical connection.
• Open isolating valves on flow and return con-
nections, refill, vent and pressurise boiler. Check for
leaks.
To replace pressure gauge
• Drain down heating circuit of boiler only as de-
scribed in 'To replace pump'.
• Undo and remove screw securing pressure
gauge capillary to front section, see diagram 22.
• Carefully pull capillary from front section.
• Undo and remove two screws securing pressure
gauge to lower front panel and remove gauge.
• Fit replacement gauge in reverse order to re-
moval.
• Fit capillary of new gauge to front section using
new 'O' ring supplied.
• Open isolating valves on flow and return connec-
tions, refill, vent and pressurise boiler. Check for leaks.
To replace reversing valve assembly
• Remove pressure gauge capillary as described
previously.
• Remove pump as described previously.
• Remove microswitch assembly as described pre-
viously.
• Remove retaining clip from LHS pipe connection
on front section of valve and disengage pipe.
• Unscrew and disconnect heating flow (centre)
connection at fixing jig.
• Remove retaining clip from heating flow pipe
connection on right of front section.
• Remove flow pipe from boiler.
• Unscrew and disconnect heating return (left
hand) connection at fixing jig.
• Remove retaining clip from expansion vessel pipe
connection at rear of reversing valve assembly and
disengage pipe, pushing pipe back and out of re-
versing valve.
• Undo and remove large screw holding water
valve to back plate of reversing valve assembly,
see diagram 23
• Push water valve back to disengage it from re-
versing valve.
• Unclip and remove loss of water pressure switch
from left of reversing valve assembly, see diagram
24.
• From below boiler, undo and remove three
screws holding reversing valve to bottom plate of
boiler. Remove complete reversing valve assem-
bly from boiler.
• Undo and remove heating return connecting
pipe and hose from rear of reversing valve assem-
bly. Fit hose to replacement reversing valve assem-
bly.
• Fit replacement reversing valve into boiler in re-
verse order to removal.
Note: Use new 'O' rings, retaining clip, filter and
washer provided.
• Unscrew and remove microswitch assembly from
top of replacement reversing valve assembly to
allow refitting of water valve.
Diagram 22
Cla 007
Diagram 23
Des 054
SERVICING INSTRUCTIONS
Diagram 24
Sec 059