Glow-worm Energy Saver Combi 2 and Gas Valve - Manual (Page 35)

35 221854B
14.19 Heat Exchanger
Refer to section 12.9 and drain the boiler heating circuit.
Refer to Section 12.10 and drain the boiler hot water circuit.
The right hand casing panels should be removed as described
in section 12.8.
Remove the gas valve as described in section 14.11.
Remove the fan and burner as described in section 12.3.
Remove the central heating flow thermistor as described in
section 14.8.
Remove the ignition electrode as described in section 12.4.
Remove the pump as described in section 14.14.
Remove the hot water cylinder as described in section 14.18.
This may not be required if there is sufficient clearance to the left
of the boiler to allow removal of the left hand casing panel.
Remove the automatic control module as described in section
14.4.
Remove the air pressure switch as described in section 14.20.
Remove the wire clip on the internal flue adaptor pipe and pull
the adaptor pipe down into the flue outlet pipe, see diagram 7.5.
Pull the flue outlet pipe out of the heat exchanger.
Remove the automatic air vent pipe from the top right hand side
of the heat exchanger.
Pull the condensate pipe off the top of the condensate siphon.
Unscrew the heat exchanger condense pipe from the base of
the heat exchanger.
Undo the heat exchanger flow pipe connection from the bottom
left hand side of the boiler.
Undo and remove the return pipe locking plate from the rear
panel below the heat exchanger and pull the return pipe down
and out of the casting.
Prise open the heat exchanger retaining clips on the back panel
of the appliance and remove the heat exchanger.
After refitting the heat exchanger , fill, vent and pressurise the
boiler and check for leaks.
14.20 Air Pressure switch
Remove the sensing tube from the air pressure switch.
Disconnect the wires. Unclip the air pressure switch from its
plastic retaining clip. Fit the new air pressure switch with the
sensing pipe connections downwards, see diagram 14.6.
14.21 Condensate siphon
See diagram 9.1.
Unscrew the drain cap on the siphon and drain off the
condensate.
Disconnect the drain pipe from the outlet of the
siphon. From underneath the baseplate, unscrew the two
condensate siphon securing screws. Pull the condensate siphon
trap away from the bottom of the appliance and disconnect the
heat exchanger condensate pipe.
Check the condensate siphon gasket and if necessary replace
prior to refitting the assembly.
Insert the heat exchanger condensate pipe onto the trap and
siphon assembly prior to fixing to the boiler base. Ensure pipe
14 Replacement of Parts
Diagram 14.5
6540
PRESSURE
GAUGE
RETAINING
LUGS
LOCATION
PIN
SLOT
is not kinked after trap/siphon has been refitted.
Refill the condensate siphon as recommended in section 9.4.
14.22 Display PCB
Unscrew the two securing screws, one on the top front edge of
the base panel and the second on the bottom edge of the base
panel. Carefully remove the ribbon wire plug from the display
PCB. Unclip the PCB from its four retaining pillars on the PCB
cover.
When refitting the PCB and cover to the appliance base panel
be careful not to trap the ribbon wire behind the cover. The
ribbon wire should exit from the right hand side of the cover.