33
221873B
SAFETY VALVE
WASHER
7085
Diagram 14.5
UNION
NUT
Diagram 14.6
SECURING
SCREW (2)
RETAINING
BRACKET
(2)
PRESSURE
GAUGE
7026
FACSIA
14 Replacement of Parts
14.6 Boiler Overheat Cutoff
Before starting refer to Section 11.
Disconnect the electrical connections, unclip to remove the
overheat cutoff, see diagram 14.4.
14.7 Pressure Gauge
Before starting refer to Section 11.
Remove case base, see diagram 10.3.
Open the controls cover door. Remove the two screws securing
the controls facia, see diagram 9.1.
Hinge the control fascia open.
Release the water pressure and drain the central heating circuit
of the boiler, refer to Section 11.3 and 11.6.
Disconnect the pressure gauge connection from the safety
valve, discard the washer, see diagram 14.5.
Remove the pressure gauge, see diagram 14.6.
Locate the supplied washer under the pressure gauge connection
when refitted to the safety valve.
14.8 Control Board
Before starting refer to Section 11.
Remove the two screws securing the controls facia, see diagram
9.1.
Hinge the control fascia open.
Remove the cable entry covers, see diagram 10.2.
Disconnect the multi-pin connectors retained by clips, see
diagram 14.7.
Remove the controls board cover, see diagram 10.2.
Disconnect the remaining multi-pin connector retained by a clip.
Remove the control board securing screw and the control board
from the support posts, see diagram 14.8.
THE MAIN CONTROL BOARD MUST BE KEPT IN THE ANTI
STATIC HOLDER UNTIL IMMEDIATE REQUIREMENT.
When replacing the main control board check and if necessary
adjust the main burner gas pressure in both the hot water and
central heating modes. Refer to “Commissioning” in the
Installation Instructions.
14.9 Gas Control Valve
Before starting refer to Section 11.
Remove the two screws securing the controls cover door and
controls fascia, see diagram 9.1.
Hinge the assembly open.
Disconnect multi-pin connector
Support the gas control valve, remove the eight socket head
capscrews at the sides of the gas control valve, see diagram
14.9.
Separate the valve from the pipes, noting the fitted position.
Discard the “O” rings and fit the new ones supplied.
Check and adjust the main burner gas pressure in the hot water
and central heating modes, refer to “Commissioning” in the
Installation Instructions.
OVERHEAT
CUTOFF
Diagram 14.4
7994
ELECTRICAL
CONNECTORS
CLIP
THERMISTOR
CENTRAL
HEATING
RETURN
FLOW
PIPE
GAS CONTROL
VALVE
