Testing Combustion Air/Flue Gas At Set Heat Output; Testing The O Or Co Level In The Combustion Air - Bosch Worchester GREENSTAR ZWB 7-27 HE combi Installation And Servicing Instructions

7.2

Testing combustion air/flue gas at set heat output

7.2.1 Testing the O
2
tion air
By testing the O
i
bustion air the gas tightness of a type C
or C flue system can be checked. The
33
O level must not be less than 20,6 %.
2
The CO level must not exceed 0,2 %.
2
B Press and hold the
shows – –.
"Chimney sweep" mode is now active.
The button will light up and the display shows the
CH flow temperature.
In "chimney sweep" mode, the appliance
i
switches to max. rated heat output or the
set heating output. You then have 15 min-
utes in which to measure the levels. After
that, the appliance switches back from
"chimney sweep" mode to normal mode.
B Remove sealing plug from combustion air testing
point (234.1, fig. 47).
B Insert testing probe about 80 mm into the testing
point and seal testing point.
234
Fig. 47
B Measure O
and CO
2 2
B Refit sealing plug.
B Press and hold
button until the display shows – –.
The button will stop flashing and the display
shows the CH flow temperature.
6 720 610 576 GB (02.05)
or CO level in the combus-
2
or CO level in the com-
2 2
13
button until the display
234.1
6 720 610 332-65.1R
levels.
Converting the appliance to different gas types
7.2.2 Testing CO and CO
B Press and hold the
shows – –.
"Chimney sweep" mode is now active.
The button will light up and the display shows the
CH flow temperature.
You have 15 minutes in which to measure
i
the levels. After that, the appliance switch-
es back from "chimney sweep" mode to
normal mode.
B Remove sealing plug from flue gas testing point
(234, fig. 47).
B Insert testing probe about 135 mm into the testing
point and seal testing point.
B CO- and CO
levels.
2
B Refit sealing plug.
B Press and hold
button until the display shows – –.
The button will stop flashing and the display
shows the CH flow temperature.
2
button until the display
31