Equivalent Vent Length Calculation Example - Vertical - Viessmann Vitodens 100-W WB1B Series Installation Instructions Manual

Rigid Venting Systems Installation Instructions
Component Installation Guide

Equivalent vent length calculation example - vertical

Fig. 94 Equivalent vent length calculation example
Single Pipe Venting (Room Air Dependent)
(continued)
Equivalent vent length calculation example (stainless steel
system)
Vitodens 100-W, WB1B 26, 35
2 x 90º elbow...........................................6 ft. (1.8 m)
2 x 45º elbow...........................................4 ft. (1.2 m)
3 x vent pipe (0.5 m)..............................4.9 ft. (1.5 m)
2 x vent pipe (1 m).................................6.6 ft. (2 m)
Total equivalent length...........................21.5 ft. 6.5 m)
Above example will change as follows if using CPVC venting
system (first 90º elbows are not included):
2 x 90º elbow.........................................10 ft. (3.1 m)
2 x 45º elbow...........................................6 ft. (1.8 m)
3 x vent pipe (0.5 m)..............................4.9 ft. (1.5 m)
2 x vent pipe (1 m).................................6.6 ft. (2 m)
Total equivalent length..........................27.5 ft. (8.4 m)
Table 38
Type of fitting
90º long sweep elbow (CPVC)
45º long sweep elbow (CPVC)
Note: See also table 36.
Legend
A Vent pipe 3.3 ft. (1 m)
B 45º elbow
C Vent pipe 1.6 ft. (0.5 m)
D 90º elbow
Equivalent length
5 ft. (1.52 m)
3 ft. (0.91 m)
85