Installation guide

Direct Venting (Two-pipe System)
62
Vent Length Requirements
Maximum equivalent vent length - CPVC system
Table 44. (see also fig. 55)
Type of fitting
Equivalent length
ft./m
90° long sweep elbow (CPVC) 5 / 1.52
45° long sweep elbow (CPVC) 3 / 0.91
Equivalent vent length calculation example
(Vitodens WB1B or WB2B system diameter 2”)
Maximum allowable equivalent length is 86 ft. / 31 m
(see table 39 and fig. 49 on page 56)
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
..........................................................................
Legend
Support system
Exhaust pipe termination with
screen
Combustion air intake with screen
a Equivalent vent length (exhaust)
b Equivalent vent length (air intake)
5368 815 v2.0 b
Support
System
Support
System
B
Side Wall
Caulk here
(exterior caulking)
Air
Vitodens 100
Fig. 56 Vitodens 100-W and 200-W, WB2B 9-19, 9-26, 9-35
Flue
C
b
a
A
Flue starter adaptor
Air intake starter adaptor
Boiler adaptor
Exhaust/Air
intake
pipe fittings
Field
supplied