Benchmark ZWB 7-29 CC1 Installation And Servicing page 32

Converting the appliance to different gas types
B Turn the temperature control
shows 2. (= max. rated heat output).
The display and the
6 720 610 332-61.1O
Fig. 45
B Measure the CO
level.
2
B Prise off the seal on the gas flow restrictor.
B Adjust the gas flow restrictor (63) to obtain the CO
level given in Table 17. Refer to fig. 46.
Fig. 46
CO
at max.
rated heat
Gas Type output
Natural gas type 9.2 %
G20
LPG G31 10.8 %
(propane)
Table 17
B Turn the temperature control
the display shows 1. (= min. rated heat output).
The display and the
6 720 610 332-63.1O
Fig. 47
B Measure the CO
level.
2
32
until the display
button will flash.
reading CO reading
2 2
at min.
rated heat
output
8.8 %
10.5 %
anti-clockwise until
button will flash.
B Remove the seal from the gas valve adjusting
screw (64) and adjust the CO
given in Table 17 for min. rated heat output.
2
3928-74.1R
Fig. 48
B Recheck the levels at min. and max. rated heat output
and re-adjust if necessary.
B Turn the temperature control
far as the stop so that the display shows 0.
(= Normal operating mode).
The display and the
B Press and hold the
shows [ ].
B Reset the temperature controls
original positions.
The display will revert to the CH flow temperature.
B Remove testing probe from the flue gas testing
point (234) and refit sealing plug.
B Re-seal gas valve adjusting screw and gas flow
restrictor.
B Replace outer case and secure.
level to the figure
2
64
anti-clockwise as
button will flash.
button until the display
and
6 720 610 599 GB (03.02)
to their