8. REPLACEMENT OF PARTS
CONTENTS
8.0
GENERAL
8.1
PRECAUTIONS
8.2
ACCESS
8.3
REPLACEMENT PROCEDURE
8.4
ELECTRICAL COMPONENTS
8.4.1
CONTROL PANEL
8.4.2
BOILER FLOW & RETURN THERMISTORS
8.4.3
CABINET TEMPERATURE SENSOR
8.4.4
FLUE THERMISTOR
8.4.5
WATER PRESSURE SWITCH
8.4.6
MAIN CONTROL PCB
8.4.7
COMBUSTION BLOWER
8.4.8
GAS CONTROL VALVE
8.4.9
FLOW THERMOSTAT
8.5
SPARK IGNITION/FLAME DETECTION ELECTRODE
8.6
BURNER
8.7
HEAT EXCHANGER
8.8
CONDENSATE TRAP
8.0
GENERAL
The following must always be carried out by a competent/qualified person.
8.1
PRECAUTIONS
i)
Always switch off the mains electricity supply and disconnect the plug at the isolating
switch and socket. (If a switch only is used then remove the fuse.)
ii)
Gain access to the appliance (Section 8.2) and turn off the gas supply at the
appliance service cock.
WARNING :
Parts of the boiler internal wiring will remain live even after setting the
User Controls to Standby. Shut off the power supply at the isolating
switch before working on the appliance.
8.2
ACCESS
i)
Remove the cabinet by removing the screws to the top and bottom of the cabinet.
8.3
REPLACEMENT PROCEDURE
i)
Always replace in the reverse order unless otherwise stated.
ii)
Electrical connections must be remade in accordance with the Electrical Wiring
Diagram (Section 6.5).
iii)
Test the tightness of any gas carrying or water carrying joint broken during the service
procedures.
8.4
ELECTRICAL COMPONENTS
8.4.1
Control Panel
(Fig. 6.7.1 item 112)
i)
Isolate the appliance (Section 8.1)
ii)
Gain access (Section 8.2)
iii)
Remove the user control cover by removing the four retaining screws (Fig
6.7.1, item 125 and item 124).
iv)
Disconnect the Control Panel by unplugging the cable connector.
v)
Remove the Control Panel by removing the four retaining screws (Fig 6.7.1,
item 141).
vi)
Reassemble (Section 8.3)
vii)
Check for correct operation of the Control Panel.
WD440/3/2007 Chapter 8 : Replacement Of Parts
The Keston Qudos 28h & Qudos 28hP
Boilers
Installation & Servicing Instructions
Page : 45
