Setting The Gas-Air Ratio (Co2 Or O2) - Bosch KBR16-3 Installation And Service Instructions Manual

12.3 Setting the gas-air ratio (CO
▶ Switch the appliance OFF using the ON/OFF switch.
▶ Remove the cover ( page 34).
▶ Switch the appliance ON using the ON/OFF switch.
▶ Unscrew a plug, indicated in the figure below, to open one of the flue
gas test ports.
Fig. 71 Open one of the flue gas test ports
▶ Insert the probe approximately 2-3/4 inches (70 mm) into the test
port and seal around it.
▶ Press and hold the emissions test button
The display shows the supply temperature alternating with
maximum set output in heating mode.
▶ Briefly press the emissions test button
The display shows the supply temperature in alternation with
maximum nominal output.
▶ Measure the CO or O level and the CO content of the flue gas
2 2
( Section 13).
▶ On the gas throttle, break the seal at the slot and remove the cap.
Fig. 72 Remove seal from the gas throttle
▶ Adjust the gas throttle to match the CO
nominal output according to table 22.
Greenstar FS
or O )
2 2
6720810590-64.1Wo
until it lights up.
=
.
=
or O level for maximum
2 2
Fig. 73 Set CO or O level for maximum nominal output
2 2
Maximum nominal
output
Gas type CO
2
NG 9.4 %
LPG (propane) 11.0 %
Table 22 CO or O values at maximum and minimum nominal output
2 2
▶ Briefly press the emissions test button
The display shows the supply temperature in alternation with
minimum nominal output.
▶ Measure the CO or O level and the CO content of the flue gas
2 2
( Section 13).
▶ Remove the sealed screw ( Fig. 74, [3]) from gas valve
adjustment screw ( Fig. 74, [2]) and set CO
minimum nominal output.
3
2
1
Fig. 74 Set CO or O level for minimum nominal output
2 2
[1] Gas inlet pressure test point
[2] Minimum adjustment screw
[3] Minimum adjustment screw cover
▶ Re-check settings at maximum and minimum nominal output and re-
adjust if necessary.
▶ Repeatedly press the emissions test button
out.
The display returns to the supply temperature.
▶ Record the CO or O levels and the CO content of the flue gas in the
2 2
commissioning log.
▶ Reinstall the screw ( Fig. 74, [3]) to cover the gas valve
adjustment screw.
▶ Remove flue gas probe and refit the plug into the flue gas test port
and tighten to secure.
Gas type conversion | 63
Minimum nominal
output
O CO O
2 2 2
4.0 % 8.6 % 5.5 %
4.2 % 10.4% 5.1 %
.
or O level for
2 2
until the light goes
6 720 810 590 (2015/05)
=