Replacement Of Parts - Bosch Greenstar ZWBR 7-25 A 23 Installation And Servicing Instructions

Brush any dust from the controls using a soft non-metallic brush
and battery operated vacuum cleaner.
If any parts need replacing then refer to Section 16.
On completion of the service check for gas soundness and the
correct operation of the appliance as described in Section 12.
Refit the cabinet and check that the controls are set to the user's
requirements.

16. Replacement of Parts

Important: Switch off the electricity and gas supplies before
replacing any components.
After the replacement of any component check for gas
soundness, where relevant, and carry out functional checks as
described in Section 13.
Any gasket or seal which appears damaged must be replaced.
It will be necessary to drain the appliance to remove some
components.
Drain the Appliance
Check that the electrical supply to the appliance is turned off.
When the mains electricity is re-established the appliance will go
through the siphon check procedure. refer to Section 13
commissioning.
Close the central heating flow and return valves and the mains
inlet to the hot water circuit at the manifold.
Place a container beneath the drain point adjacent to the relief
valve and unsrew the plug. See Fig.15.
The appliance drainage can be completed through a drain point
at the bottom of the DHW heat exchanger. Remove the plug in
the base of the casing, place a container beneath the opening
and unscrew the sealing nut.
To gain access to the components it is necessary to remove or
reposition :
a) Facia Cover Panel
Lower to the 'horizontal' position and push firmly upwards at
the side location points to release. Remove the panel.
b) Cabinet
Release the clips at the rear of each side of the appliance and lift
off. Refer to Fig.9.
c) Facia Assembly
Unplug the spark and electrode connection. Unscrew the screws
at each end of the facia and lower assembly. Refer to Fig.15.
Fig. 22. Control Board and Transformer.
Ignition Lead
Connection
Connections
Cover
Fig. 21. Facia connections cover.
d) Inner Case Cover
Unscrew the four screws and remove the cover.
e) Facia Assembly - Removal.
Remove the facia cover panel. Unclip the lower facia cover,
unscrew and remove the controls connection cover. Refer to
Fig.20. Pull off the spark and sense electrode connection. Pull off
the or disconect the mains, multiway, fan/burner and pump
leads. Unplug the appliance code plug - DO NOT REMOVE FROM
THE APPLIANCE.
Disconnect all the earth connections including that from the rear
of the assembly to the main body of the appliance.
Unscrew the two fixing screws to lower the facia and lift from the
side supports.
Control Board
Disconnect all the leads described in (e). Unplug the ignition lead
connections and lower the facia.
Unscrew the four screws securing the metal cover and carefully
prise off the cover. Refer to Fig.22.
The TRANSFORMER can now be removed from the board.
Ease out the control board from the facia.
Transformer
Cover Plate
External
Programmer Control
Cover
Control Cover (Spare)
24
Facia
Lower Facia cover
(clip-on)
Controls
Connections
Cover
Fixing Screw
CERAPUR:
Diagram 8
26/3/99
Cover Plate
Fixing
Screws
Control
Board
Code Plug
Facia