Technical data

22
Fig. 21
Alpha SY9-24 - Component Replacement
8.11 VIEWING WINDOW
1. Gain access behind the casing as in section 8.1.
2. Remove the rubber window frame and remove the damaged glass.
3. Re-assemble in reverse order with a new glass. Ensure the rubber frame is located correctly in the front panel.
8.12 INTERNAL FUSE - Refer to Fig. 14
The fuse is located in the boiler terminal block.
1. Gain access as described in Installation, section 4.8.
2. Lift out the fuse holder and remove the fuse. Fit a fast blow 2 A fuse as a replacement, ensuring that the holder snaps into position.
3. Re-assemble in reverse order, ensuring the terminal block is located correctly on the plastic pins.
8.13 PCB - Fig. 21
1. Gain access behind the control panel as described in section 8.1.
2. Disconnect all the wiring connectors from the PCB.
3. Remove the five fixing screws and carefully withdraw the board from the switch spindles.
4. Re-assemble in reverse order. Refer to the wiring diagram in section 9.1 for connections.
8.14 HEAT EXCHANGER
1. Gain access to the combustion chamber and drain the boiler heating circuit as described in sections 8.1 and 8.2.
2. Remove the four screws securing the combustion chamber front cover and remove the cover.
3. Remove the overheat thermostat (section 8.9) and the CH temperature sensor (section 8.17).
4. Remove the right hand side baffle plate by lifting it up.
5. Disconnect the two unions from the heat exchanger flow and return pipes.
6. Lift up the heat exchanger off the pipes and remove it by carefully withdrawing it out of the boiler.
7. Carefully prise off the two clips and remove the flow and return pipes from the heat exchanger.
8. Fit the flow and return pipes to the new heat exchanger, ensuring the new 'O' rings are in position in the flanges.
Lubricating the 'O' rings with a soap solution will aid assembly. Ensure the heat exchanger is correctly located.
9. Re-assemble in reverse order.
10. Refill and pressurise the system. (Refer to Commissioning, section 5.1).
8.15 COMBUSTION CHAMBER INSULATION
1. Gain access to the combustion chamber as described in section 8.1.
2. The front panel slides out.
3. To replace the rear and side panels remove the heat exchanger as described in section 8.14. Prise out the top of the rear
insulation panel and lift it up and out of the boiler, then slide out the side insulation panels.
4. Fit a new panel and re-assemble in reverse order.
5. Refill and pressurise the system. (Refer to Commissioning, section 5.1).