51
3044826_201403
Service Manual
- Terminate the emissions test mode by turning the tempera-
ture selector back into its original position.
- Turn clockwise
- lower CO
2
content
- Turn anti-clockwise - higher CO
2
content
Gas flow adju-
sting screw
Fig.: Gas combination valve
Adjusting the gas:air mixture
Carry out the adjustments in the following sequence:
At the factory, the gas combination valve has been
adjusted for the gas type stated on the type plate.
Only adjust the gas combination valve after the
system has been changed to a different gas type.
NB
A) CO
2
adjustment at the upper load
(emissions test mode)
- Pivot the control unit lid down.
Unlock the casing lid with the l.h. and r.h. rotating locks.
Release the lower part of the casing lid and unhook at the
top.
- Remove the screw from the l.h. „Flue gas“ test port.
- Insert the test probe of the CO
2
test equipment into the „Flue
gas“ test port.
- Turn the temperature selector to the emissions test position,
(illuminated status display ring flashes yellow).
- Check the CO
2
content at full load, and compare the actual
value with those in the table below.
- Pivot the control unit out and correct the CO
2
content with
the gas flow adjusting screw on the gas combination valve
(in accordance with the table).
boiler open
at
upper
load
Natural gas H
8,8% ± 0,2%
LPG P
9,9% ± 0,3%
Fig.: Open the rotating locks
rotating lock
Fig.: Flue gas test with an open boiler
„Flue gas“ test port
