Maximum Vent Pipe Length - Vertical - Viessmann Vitodens 100-W WB1A-24 Installation Instructions Manual

Vent Length Requirements

Maximum vent pipe length - vertical

Table 47. Maximum allowable equivalent length - vertical
Boiler Model
HWB1A 8-24, 8-30
HWB2 6-24C, 6-24
HWB2 8-32
HWB2 11-44
HWB2 15-60
*
4" (3" to 4" increaser field supplied. Do not order Viessmann 4" parallel adaptor)
Maximum of five 90° elbows allowed in the vent system (first 90º elbow is not included).
See Fig. 47.
Minimum vent length is 3.3 ft. / 1m.
b
a
Fig. 61
(continued)
System Ø Max. equivalent
2" / 51mm
3" / 76mm
*
4" / 102mm
3" / 76mm
4" / 102mm
3" / 76mm
4" / 102mm
4" / 102mm
(for larger Ø system
consult Viessmann)
4" / 102mm
(for larger Ø system
consult Viessmann)
Legend
Exhaust (straight coupling) with
screen
Flashings
Support system
Combustion air intake
a Equivalent length (exhaust)
b min. 18" / 457mm
max. 48" / 1219mm
Single Wall Venting (Room Air Dependent)
vent length (a)
40ft. / 12m
66ft. / 20m
79ft. / 24m
66ft. / 20m
79ft. / 24m
49ft. / 15m
62ft. / 19m
66ft. / 20m
49ft. / 15m
Size the exhaust vent pipe as specified
in the table on the left. This table lists
the maximum allowable vent length in
ft. and meters of the exhaust piping.
Vent diameter must not be reduced at
any point in the installation.
71