SERVICING AND SPARES
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3. Clean the heat exchanger from top to bottom using the brush.
▶ Refit the clean out cover plates in reverse order using a new seal (C)
and tighten screws.
6.1.5
TO CLEAN THE BURNER
1. Remove cover panel (A) by removing the screws (B).
▶ Check that the boiler is completely isolated from the gas supply.
Fig. 67
2. Remove the clips (C) and unscrew the two bolts (D).
▶ Unscrew and remove the two hexagon screws (E) securing the fan.
▶ Slacken fully the rear securing bolt (F).
▶ Remove the burner cover plate (G).
Fig. 68
3. Remove the burner (H) and clean components.
Do not use a wire brush.
Fig. 69
6.1.6
TO CHECK THE DIAPHRAGM IN BURNER COVER
4. Carefully withdraw diaphragm (J) from fan intake tube and check for
soiling and splits.
▶ Carefully refit diaphragm (J) the correct way round into the fan intake
tube, the diaphragm flaps must open upwards.
▶ Re-assemble burner in reverse order using a new seal (K).
▶ Adjust gas/air ratio. Refer to section “Setting the gas/air ratio”.
3.
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A
B
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B
1.
F
C
D
2.
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H
G
E
E
3.
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J
I
K
I
4.
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