Glow-worm 56-2 Back Boiler - Manual (Page 18)

18 221781A
9 Replacement of Parts
Diagram 9.2
8019
Diagram 9.3
NOTE: It is important that the thermostat is
fitted the same way as shown in diagram
CONTROL
KNOB
ELECTRICAL
CONNECTIONS
THERMOSTAT
SECURING
SCREW(2)
SENSING
TUBE
FITTING
ASSEMBLY
THREAD CUTTING
SCREW(Taptite)
1 mm
BACK
BOILER
SENSING TUBE
BULKHEAD CONNECTION
TUBING
NUT
BOILER AIR DUCT
SENSING
TUBE
FITTING
ASSEMBLY
FRONT FACE
OF BOILER
CASTING
FILTER
Diagram 9.4
6129
9.2 Flue Blockage Safety Device Assembly
Gain access as the relevant part of Section 8.3.
Remove lead from electrode.
Pull off back boiler lower sensing tube.
Undo the pilot tube securing nuts and the thermocouple nuts at
gas valve, see diagram 8.4.
Undo the flue blockage safety device assembly securing screws
and withdraw, see diagram 8.4.
When refitting take care not to damage the lower sensing tube
adapter “O” rings.
9.3 Gas Valve
Gain access as the relevant part of Section 8.3.
Disconnect the thermocouple tube nut at the gas valve and
ease out of the valve, see diagram 8.4.
Disconnect the pilot tube nut at the gas valve.
Undo the securing screws to separate the gas valve from the
supply pipe flange. Take care not to damage the “O” ring seal
between the flanges.
Undo the two securing screws to release gas valve from the
combustion chamber extension, see diagram 8.2.
Transfer the union nut and liner to the replacement gas valve
using a small amount of approved jointing compound on the
external thread only.
When fitting the thermocouple only tighten the nut at the gas
valve a quarter turn beyond finger tight.
9.4 Ignition Lead
Gain access as the relevant parts of Section 8.3.
Remove the lead from the electrode and piezo unit.
Fit the silicone sleeve over the new lead.
Fit the black insulated end of the ignition lead to the piezo unit
and the clear end to the electrode.
Push the silicone sleeve into position, see diagram 8.4.
9.5 Main Burner Injector
Gain access as the relevant parts of Section 8.3.
Refer to diagram 8.4 and undo the thermocouple nut and
withdraw the thermocouple.
Undo the pilot tube nut at the gas valve control.
Refer to Section 8.3 paragraph eleven.
When replacing the main burner injector use a small amount of
approved jointing compound on the external thread only.
9.6 Pilot Burner Injector
Should pilot burner injector need replacing, the whole pilot
burner assembly must be replaced.
9.7 Piezo Unit
Gain access as the relevant parts of Section 8.3.
Disconnect the ignition lead from the piezo unit, see diagram
9.1.
Note: To ease the removal of the piezo unit it is advisable to
temporarily remove the boiler thermostat from the control box,
refer to Section 9.8.
Depress the retaining tabs and remove the Piezo unit.
SELF ADHESIVE
ALUMINIUM FOIL
GASKET
MICA WINDOW
PEEL OFF
BACKING
PAPER
OPENING
(PILOT
BURNER)
7886