Routing The Flue Gas Via A Moisture-Resistant Chimney With Gn Set - Buderus Logamax plus GB162 Technical Manual

9 Flue systems for open flue operation
9.6

Routing the flue gas via a moisture-resistant chimney with GN set

Appliance type B (formerly B
23
Observe the general information on page 108 ff.
Logamax plus Maximum
permissible
total length
L
[m]
GB162
Table 53 Maximum permissible total flue length
( fig. 113)
1) These lengths include the pipe diversions included in the
standard set
2) Up to three reductions for additional bends or inspection bends
can be taken into consideration; more than three must be
checked on an individual basis
Adequate combustion air supply
According to the Technical Rules for Gas Installations
DVGW-TRGI 2008 [Germany], the adequate supply of
combustion air in the installation room requires vents
towards the outside with a free cross-section of
2
1 × 150 cm or 2 × 75 cm
2
An additional 2 cm are required for every kilowatt in
excess of 50 kW total rated output (
page 110).
Chimney connection
Even when connecting the Logamax plus GB162 to a
moisture-resistant special chimney, only a flue approved
together with the gas condensing boiler that is suitable for
positive pressure (e.g. Buderus standard GN set) may be
used as a connection piece. In Germany, the
moisture-resistant chimney must be approved by the
Deutsches Institut für Bautechnik (DIBt).
Sizing the moisture-resistant chimney
The sizing of the connection piece and the chimney must
ensure that positive pressure in the gas-tight flue is
reduced and consequently only negative pressure
persists inside the moisture-resistant chimney
( fig. 113). Only the relevant manufacturer should
calculate and deliver the moisture-resistant chimney.
The flue gas parameters must be known to enable the
calculation to be carried out (
Inspection apertures
Allow for inspection apertures in accordance with
regulations ( page 114 f.).
124
)
23
Reduction of the
total length for each
additional pipe
1) 2)
diversion
[m]
2 none
2
(up to 50 kW rated output).
tab. 44,
tab. 54).
GN set
A
B
A
3)
F
3)
Fig. 113 Installation version (dim. in mm)
A Positive pressure
B Atmospheric pressure
C Reduction of positive pressure
D Chimney manufacturer
E Flue gas
F Ventilation air
1)
Flue pipe
2)
Connection piece supplied by the manufacturer of the
moisture-resistant chimney
3)
Vent to the outside (
Special installation room > 50 kW
6 720 645 821 (2010/09) – Logamax plus GB162
D
C
∅80 1)
E
3 4 5
2
1 2)
L
6 720 641 280-56.1il
tab. 44, page 110)
page 111