20
221763A
9 Replacement of Parts
9.8 Piezo Unit
Pull door forward at the top to disengage the studs and lift to
release from slots, see diagram 7.3.
Remove mains inlet connector by pulling downwards, see
diagram 8.1.
Gain access to inside of the control box by removing the
securing screw located at the top of control box and unhooking
at the bottom, see diagram 9.4.
Disconnect the ignition lead at the piezo unit.
Note: To ease the removal of the piezo unit it is advisable to
temporarily remove the boiler thermostat from the control box.
Depress the retaining tabs and remove the Piezo unit.
9.9 Ignition Lead
Gain access to the boiler as Section 8.1.
Disconnect the ignition lead at the piezo unit, see diagram 9.4
and section 9.8.
Disconnect the lead at the spark electrode, see diagram 9.2.
When reconnecting lead make sure that the clear end is fitted
to the spark electrode.
9.10 Electrical Control Box
Gain access to the boiler as Section 8.1.
Disconnect the mains inlet connector, see diagram 8.1.
Remove the thermostat phial by removing the retaining split pin
from the phial pocket and withdrawing the phial, see diagram
4.5.
Disconnect the gas valve plug from the valve, see diagram 9.1.
Pull the ignition lead off at the piezo unit, see diagram 9.4.
Remove the electrical control box cover securing screw and
unhook the cover at the side.
Remove the two screws and nuts to release the box from the
support bracket.
Refit the thermostat phial as Section 8.5.
Diagram 9.5
CONTROL BOX AND GAS VALVE WIRING
6284
CHASSIS
EARTH
230V~ 50Hz
MAINS SUPPLY
FUSED AT 3A
BLUE
BLACK
GREEN / YELLOW
BROWN
C
THERMOSTAT
GAS VALVE
N
E
N
L
VIEW OF PLUG
WHEN REMOVED
L
GREEN/
YELLOW
N/C
7995
ELECTRICAL
CONNECTORS
ELECTRICAL
CONTROL BOX
COVER
COVER
SECURING
SCREW (4)
ELECTRICAL
CONTROL BOX
THERMOSTAT
SECURING
SCREW (2)
THERMOSTAT
CONTROL KNOB
PIEZO
UNIT
HOOK
IGNITION LEAD
(BLACK END)
CUT-OUT FOR
CAPILLARY
SECURING SCREW
THERMOSTAT
AND CAPILLARY
Diagram 9.4
CONTROL BOX