25
7.2
PREPARE FOR SERVICING - Fig. 26
1.
Ensure the electrical supply is isolated and the gas
supply is off.
2.
Unscrew the two screws securing the control panel
and lower the panel.
3.
Lift the case front panel upwards slightly and pull it
forwards to remove it from the boiler.
4.
Remove the four screws, or for the CD32C, release the
four clips securing the room sealed chamber panel and
remove the panel, taking care not to damage the seal.
5.
Disconnect the gas supply pipe union.
6.
Remove the two screws securing the fan assembly to
the combustion chamber front.
7.
Remove the two pressure tubes, noting their
positions.
8.
Disconnect the electrode lead from the ignition
generator and the in-line connector to the flame
sensing electrode.
9.
Remove the six nuts and washers securing the
combustion chamber front assembly and remove the
assembly.
7.3
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. Any damaged panels must be replaced. (Refer to
Component Replacement, section 8.18).
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 injectors.
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 any injector that appears damaged.
6.
Remove the four screws securing the burner (see Fig. 27) 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. See Fig. 27.
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.
7.4
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 and the seal is in position in the bottom of the room sealed chamber.
4.
Test the connections for gas soundness and re-commission, sections 5.4 and 5.5.
5.
Ensure that the room sealed chamber panel seal is intact and in position, replace the panel ensuring it has been located
correctly (especially on the sides) and secure it in position with the screws previously removed.
6.
Place the front case panel in position as shown in Fig. 26 and secure in position.
7.
Raise the control panel and secure in position with the two screws provided.
8.
Check the operation of the boiler. (Refer to Boiler Operation, section 6).
9.
Return all controls to their original settings.
Alpha CD24/32 - Routine Servicing
Fig. 27
Flame sensing
electrode
Gap 11 mm (CD32C 17 mm)
Ignition electrodes
Gap 3 - 4 mm
Burner
Combustion chamber
front assembly
Front insulation
panel
Содержание Alpha CD24
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