Benchmark ZWB 7-29 CC1 Installation And Servicing page 36

Maintenance
B Loosen any deposits in the heat exchanger from top
to bottom using the cleaning blade. Refer to fig. 53.
Fig. 53
B Clean the heat exchanger from top to bottom using
the brush. Refer to fig. 54.
Fig. 54
B Flush the heat exchanger from the top. Refer to
fig. 55.
B Clean out the condensate collector and trap connec-
tion (with other end of brush).
Fig. 55
B Refit the clean-out cover using a new seal and
tighten screws to torque of approx. 5 Nm.
36
6 720 610 332-75.2R
Burner
B Check that the gas cock is turned off and the master
switch is in the OFF position
B Remove the clips (1) and unscrew the two bolts (2).
Refer to fig. 56.
B Unscrew and remove the two hexagon screws secur-
ing the fan (3).
B Slacken fully the rear securing bolt (4).
B Remove the burner coverplate.
Fig. 56
B Remove the burner skin and clean components. Do
not use a wire brush. Refer to fig. 57.
Fig. 57
B Re-assemble burner in reverse order using a new
seal.
B Adjust gas/air ratio. Refer to section 7.2.
6 720 610 599 GB (03.02)