Glow-worm Betacom2 - Manual (Page 45)

0020145065_01 - 09/12 - Glow-worm
18.5.1 Spark electrode
• Disconnect the electrode cap (7) and the earthing cable (6).
• Remove the 2 spark electrode retaining screws (8).
• Carefully remove the electrode (10) from the combustion
chamber.
• Remove the gasket (9).
• Check that the distance between the 2 electrodes is between
3.5 and 4.5 mm.
• Install the electrode and a new gasket.
18.5.2 Igniter unit
• Remove the ignition lead (2).
• Remove electrical connections (4).
• Loosen the screws (3) located on the igniter unit (2).
• Remove the igniter unit (2).
18.5.3 Removing the combustion/burner door
assembly
b ATTENTION:
The burner door seal (13) must be replaced each time
the combustion/burner door assembly is removed.
• Disconnect the spark electrode cap (7) from the igniter unit.
• Disconnect the gas supply pipe (36) at the gas valve.
• Remove the electrical connectors from the gas valve (37) and
the fan (34).
• Remove the retaining screw of the silencer.
• Loosen the 4 nuts (12).
• Remove the combustion/burner door assembly from the heat
exchanger (11).
• The studs (19) must not be damaged. If damaged you will need
to replace the heat exchanger.
• The combustion/burner door assembly insulation should be
inspected and replaced if damaged.
18.5.4 burner
• Remove the 3 burner retaining screws (16).
• Remove the burner (15) and the gasket (14).
• Fit the new burner and the new gasket.
18.5.5 Heat exchanger
b ATTENTION:
There will be water in the heat exchanger.Carefully ease
heat exchanger out.
• Drain the boiler heating and hot water circuits as described in
the appropriate chapter "Draining".
• Remove the flue connection.
• Undo the two screws located on the top of each side panel.
• Remove the thermal fuse connector (20).
• Remove the 2 heating pipe retaining clips (25) and (29).
• Release the heating pipes (24) and (27) from the heat
exchanger.
• Release the condensate trap pipe from the heat exchanger.
• Remove the combustion/burner door assembly (11) refering to
chapter "Removing the combustion/burner door assembly".
• Unscrew the 4 retaining screws (17) and (23) and remove the 2
retaining plates (18) and (22) from the heat exchanger.
• Pull the heat exchanger towards you to extract it from its 2 side
rails.
18.5.6 Re-assembling the burner group
• Place the burner assembly on the heat exchanger (21).
• Progressively tighten the 4 nuts (12) in an alternate order.
• Reassemble the silencer.
• Connect the gas pipe (36) with a new gasket to the burner
group.
• Connect the spark electrode connector (5) to the igniter unit.
• Connect the connector to the gas valve (37) and the fan (34).
• Open the appliance’s gas input.
• Check the tightness of the gas connection.
18.5.7 Heating Flow Thermistor
• Remove the electrical connections from the thermistor (28).
• Remove the retaining clip from the flow pipe (27).
i IMPORTANT:
When reconnecting, the polarity of the wiring to
thermistors is not important.
18.5.8 Heating Return Thermistor
• Remove the electrical connections from the thermistor (26).
• Remove the retaining clip from the return pipe (24).
i IMPORTANT:
When reconnecting, the polarity of the wiring to
thermistors is not important.
MAINTENANCE
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