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

Direct Venting (Two-pipe System)
Vent Length Requirements

Equivalent vent length calculation example - CPVC system

Table 29
Type of fitting
90° long sweep elbow (CPVC)
45° long sweep elbow (CPVC)
Exhaust/
Air intake
pipe fittings
Field
supplied
Fig. 59 Vitodens 100-W and 200-W, WB2B-19, 26, 35
58
(continued)
Equivalent vent length calculation example
(Vitodens WB1B system diameter 2 in.)
Maximum allowable equivalent length is 86 ft. (31 m)
(see table 24 on page 51 and fig. 59 below)
2 x 90º elbow.....................................10 ft. (3.05 m)
4 x 45º elbow.....................................12 ft. (3.66 m)
Exhaust vent pipe................................10 ft. (3.05 m)
Air intake pipe.....................................10 ft. (3.05 m)
Combined total equivalent vent length
(a+b).................................................42 ft. (12.81 m)
A
a
b
Flue starter adaptor
Air intake starter adaptor
Boiler adaptor
Legend
A Support system
B Exhaust pipe termination with screen
C Combustion air intake with screen
a Equivalent vent length (exhaust)
b Equivalent vent length (air intake)
Rigid Venting Systems Installation Instructions
Equivalent length ft. (m)
5 (1.52)
3 (0.91)
Side wall
Caulk here
(exterior caulking)
B
Flue
C
Air