Baxi 47 075 35 Installation & Servicing Instructions Manual page 53

Fig. 62
Fig. 63 and Fig. 64
13.2 Annual Servicing ­ Inspection
1. Ensure that the boiler is cool.
2. Ensure that both the gas and electrical supplies to the boiler are isolated.
3. Slacken the screws securing the facia panel. Lift the outercase panel so that its securing tabs are clear of the facia. Remove the
panel, allowing the facia to hinge down (Fig. 62).
4. Remove the screws securing the inner door panel. Lift the panel slightly to disengage it from the studs on top of the case (Fig. 63).
5. Unscrew the sump from the bottom of the condensate trap assembly (Fig. 64) and remove any deposits from the sump and trap.
Clean as necessary and replace the sump.
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6. Undo the nut on the gas inlet pipe to the venturi (Fig. 65) and pull the sensing pipe off the fan.
7. Disconnect the electrode leads, noting their position, and the fan electrical plugs (Fig. 66).
8. Undo the four nuts retaining the combustion box cover to the heat exchanger.
9. Carefully draw the fan, collector and cover assembly forward, being careful to retain the injector in the venturi (Figs. 65 & 66).
10. Clean any debris from the heat exchanger and check that the gaps between the tubes are clear.
11. Inspect the burner, electrodes position and insulation, cleaning or replacing if necessary. Clean any dirt or dust from the air box.
12. Reassemble in reverse order.
NOTE: The sensing pipe must be reconnected to the fan, not the venturi.
DHW Filter (Fig. 68)
13. If the flow of domestic hot water is diminished, it may be necessary to clean the filter.
14. Initially check the cold water inlet tap filter.
15. Turn the tap off and draw off from a hot tap. Undo the blanking cap and remove the threaded bush (Fig. 67).
16. Extract the filter and rinse thoroughly in clean water. Reassemble and check the flow. If required clean the restrictor filter as
described below.
17. Pull off the hall effect sensor. Undo the restrictor from the inlet/return manifold.
18. Rinse the filter thoroughly in clean water and reassemble in reverse order.
19. Turn the selector switch fully anticlockwise against the spring pressure to the reset position and hold for 5 seconds to reset the
boiler.