Viessmann Vitodens 200 WB2 Series Technical Data Manual page 21

Vent termination location requirements
The vent must be installed observing local regulations in addition to National Codes, CAN/CSA-B149.1 or 2 (for installations in Canada) or
ANSI-Z223.1 or NFPA 54 (for installations in the U.S.A.).
See table below for the following two conditions.
For sloped roof applications with distance b greater than 18"/450 mm
H
For flat roof applications
H
b
For sloped roof applications with distance b less than 18"/450 mm
H
b
a
a
a minimum 18"/450 mm
b <18"/450 mm
Model No. 24C/24/32
WB2- (5" system)
a (min. 25"/
a
distance) 635 mm
*1
See WARNING below.
WARNING
The vent termination must be at least
12"/300 mm above the anticipated snow
level (consult your local building authorities
or local weather office). Locate vent
termination in such a way that it cannot
be blocked by snow.
A vent used in a special vent system with
positive vent pressure and passing through
a roof shall extend at least 18"/450 mm
above the highest point where it passes
through the roof and any other obstruction
within a horizontal distance of 18"/450 mm.
The special vent system shall not be routed
into, through, or within any other vent such
as an existing masonry or factory-built
chimney.
IMPORTANT
A masonry chimney flue may be used to
route the venting system only if no other
appliance is vented in the same flue.
Venting Option
44/60
(6" system)
30"/
*1 *1
762 mm
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