Equivalent Vent Length Calculation Example - Viessmann Vitodens 200-W WB2B Series Installation Instructions Manual

Vertical Vent Installation (Coaxial)
Vent Length Requirements

Equivalent vent length calculation example

* 1
F
D
Equivalent vent length calculation example
Legend
A Vent termination
B Vent pipe 3.3 ft. (1 m)
C 45º elbow
D Vent pipe 1.6 ft. (0.5 m)
E 87º elbow
F Telescopic extension
* 1 First elbow not included in equivalent vent calculation.
28
(continued)
A
B
C
C
D
D
E
Vitodens Rigid and Flex Venting Systems Installation
Type of fitting
87º elbow/
87º inspection tee
45º elbow
IMPORTANT
Always include vent termination length in calculations.
Equivalent vent length calculation example:
Vitodens 100-W, WB1B 35 or Vitodens 200-W, WB2B 35
or Vitodens 200-W, B2HA/B2HB 35 or Vitodens 222-F,
B2TA/B2TB 35 (vent system 60/100) (see illustration on
this page).
2 x 87º elbow........................................3.3 ft. (1 m)
2 x 45º elbow...........................................2 ft. (0.6 m)
3 x vent pipe.........................................4.8 ft. (1.5 m)
1 x vent pipe.........................................3.3 ft. (1 m)
1 x telescopic extension (average length)...1.0 ft. (0.31 m)
1 x vent termination...............................4.2 ft. (1.28 m)
Total equivalent length..........................18.6 ft. (5.67 m)
Standard sizes of boiler flue gas adaptors
Boiler model
WB1B 26, 35
WB2B 19, 26, 35
WB2B 45, 60
WB2B 80, 105
B2TA 19, 35
B2TB 19, 35
B2HA 19, 28, 35
B2HB 19, 26, 35
B2HA 45, 60
B2HB 45, 57
B2HA 80, 88, 100, 112, 150
Equivalent length
1.6 ft. (0.5 m)
1 ft. (0.3 m)
*1
Adaptor Size
60 / 100
60 / 100
80 / 125
110 / 150
60 / 100
60 / 100
60 / 100
60 / 100
80 / 125
80 / 125
110 / 150