26
Alpha CD90S/115S - Routine Servicing
6.4
CLEANING THE BOILER
1.
Remove any deposits from heat exchanger using a suitable soft brush. Do not use a brush with metallic bristles.
2.
Check the condition of the combustion chamber insulation panels.
3.
Check the condition of the burner injector on the combustion chamber front assembly, carefully clean them with a
soft brush if necessary.
Do not use a brush with metallic bristles as this might damage the injector.
4.
Remove any deposits from the heat exchanger coils. This can be done by suction or water sprayed onto the coils.
Ensure all electrical components are protected from water. Any water used to clean the heat exchanger will drain to
the condensate trap.
5.
Unscrew and replace the injector should it appear damaged.
6.
Remove the four screws securing the burner and remove the burner. Clean the burner with a soft brush and check
that the flame ports are clear. Blockages may be removed with a stiffer brush. Tap the burner, open end down, to
remove any deposits from inside.
7.
Check the condition of the electrodes.
9.
Check the spark gap, positioning and height of the electrodes. Refer to Fig. 25.
10. Unscrew the condensate trap drain cap to remove any deposits.
Note:
Before removing the cap, ensure that the water released from the trap can be contained to avoid spillage.
The trap will contain no more than 200 cc of condensate water. Replace the drain cap.
Fig. 25
Electrode gap
3 - 4 mm
Burner
Burner to electrode
gap 16 mm
Flame sensing
electrode
Front panel insulation
Ignition electrodes
Combustion chamber
front assembly
6.5
RE-ASSEMBLE THE BOILER
1.
Replace the burner, ensuring it is located correctly and secure it in position using the four screws previously
removed.
Important:
Before replacing the combustion chamber front assembly, pour at least 200 cc of water into the coils of
the heat exchanger. This is to ensure the condensate trap is full of water before operating the boiler.
2.
Replace the combustion chamber front assembly, ensuring it is correctly located.
3.
Ensure the electrode lead is connected.
4.
Re-connect the gas pipe to the manifold, test the connections for gas tightness and re-commission, Sections 5.2 and
5.4.
5.
Place the case or front case panel in position and secure in position with the screws previously removed, see
Section 6.2.
7.
Check the operation of the boiler.
8.
Return all controls to their original settings.
