45
fig. 73 (Natural Gas)
GW 428/0
fig. 73a (Propane)
GW 1286/0
fig. 74
GW 466/1
fig. 75
GW 467/0
7.10 Replacement of main heat
exchanger
•
Turn off the boiler as in Section
7.1.1.
•
Release CH water pressure and
drain boiler as in Section 7.1.2.
•
Remove front casing as in Section
7.1.3 and remove combustion
chamber cover as in Section 7.1.5
•
Remove fan and burner assembly
as in Section 7.4.
•
Remove condensate sump as in
Section 7.6.
•
Pull off wires from heat exchanger
NTC (1, fig. 73), ignition electrode
(2, fig. 73) sensing electrode (3,
fig. 73) and earth wire (4, fig. 73).
•
Remove screw (5, fig. 73) and wire
from heat exchanger connecting
pipe.
•
Pull off the 2 wire pipe retaining
clips (1, fig. 74).
•
Undo the 4 nuts (1, fig. 75).
•
Pull pipe (2, fig. 74) forward to
release from heat exchanger.
•
Pull pipe (3, fig. 74) to the right
and remove heat exchanger.
•
Reassemble in reverse order.
•
Recommision boiler (see Section 5).
