Combustion Management System - Viessmann VITODENS 222-F Service Instructions Manual

Vitodens 222-F B2TA 19 and 35 Service

Combustion Management System

O content (%)
Air factor λ
2
1.20 3.8
1.24 4.4
1.27 4.9
1.30 5.3
1.34 5.7
1.37 6.1
1.40 6.5
1.44 6.9
1.48 7.3
The Vitodens 222-F, B2TA boilers come equipped with Lambda Pro, the industry's first intelligent combustion
management system. The boiler adjusts automatically to any gas type and quality without the need for a fuel
conversion kit.
The combustion management system utilizes the physical
correlation between the level of the ionization current
and the air factor λ (lambda). For all gas qualities, the
maximum ionization current results with air factor λ.
The ionization signal is evaluated by the combustion
management system, and the air factor is adjusted to
between λ=1.24 and 1.44. This range provides for an
optimum combustion quality. Thereafter, the electronic
gas valve regulates the required gas volume based on the
prevailing gas quality.
To check the combustion quality, the CO
O content of the flue gas is measured. The actual values
2
enable the prevailing air factor to be determined.
Air factor λ - CO 2 /O 2 content
The relationship between the CO
factor λ is illustrated in the table below.
To achieve an optimum combustion control, the system
regularly performs an automatic self-calibration; also after
a power failure (shutdown). For this, the combustion is
briefly regulated to max. ionization current (equals air factor
λ=1). The automatic calibration is performed shortly after
the burner starts and lasts approximately 5 seconds.
During the calibration, higher than normal CO emissions
may occur briefly.
The combustion management system can also be
calibrated manually, e.g. after maintenance or service
work (coding address "85", see Service Instructions).
CO content (%) for natural gas
2
9.6
9.2
9.0
8.7
8.5
8.3
8.1
7.8
7.6
Outdoor Reset Programming Unit
or O
2 2
CO content (%) for liquid propane gas
2
11.3
10.9
10.6
10.3
10.0
9.8
9.6
9.3
9.0
content or the
2
content and air
31