Installation guide

Vertical Vent Installation (Coaxial)
33
Vent Length Requirements (continued)
Equivalent vent calculation examples
Table 19.
Vent termination
Vent pipe (3.3 ft./1 m)
45º elbow
Vent pipe (1.6 ft./0.5 m)
E 87º elbow
F
Telescopic extension
*1
First elbow not included in
equivalent vent calculation
.
Type of fitting Equivalent
length
87º elbow/
87º inspection tee
1.6 ft./0.5 m
45º elbow 1 ft./0.3 m
Always include vent termination length
in calculations.
Equivalent vent length calculation
example
Vitodens 100-W, WB1B 10-35
and Vitodens 200-W, WB2B 9-35
(vent system 60/100) (Fig. 29)
2 x 87º elbow 3.3 ft./1 m
...........................
2 x 45º elbow 2 ft./0.6 m...........................
3 x vent pipe (0.5 m) 4.8 ft./1.5 m........
1 x vent pipe (1 m) 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
Table 20. Standard sizes of boiler flue
gas vent adaptors
Boiler model
Adaptor size
WB1B 10-26 60/100
WB1B 10-35 60/100
WB2B 9-19 60/100
WB2B 9-26 60/100
WB2B 9-35 60/100
WB2B 17-45 80/125
WB2B 17-60 80/125
WB2B 30-80 100/150
WB2B 30-105 100/150
5368 815 v2.0 b
Fig. 29 Equivalent vent length
calculation, example
*1
C
E
C
F
IMPORTANT