Vent Termination Location Requirements; Flashing And Storm Collar Installation - Viessmann Vitocrossal 300 CU3A Installation Instructions Manual

CU3A Venting Systems Installation
Component Installation Guide
For sloped roof applications with distance b less than

18 in. (450 mm)
a minimum 18 in. (450 mm)
b <18 in. (450 mm)
For sloped roof applications with distance b greater

than 18 in. (450 mm)
For flat roof applications

a minimum 18 in. (450 mm)
b >18 in. (450 mm)
(continued)
b
Vertical Vent Installation (Coaxial)

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.).
The distance between two adjacent vertical vent
terminations for all boiler sizes is 1 ft. (0.3 m) (center to
center).
WARNING
Vent termination must be at least 12 in. (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 venting system with positive vent
pressure and passing through a roof shall extend at least
18 in. (450 mm) above the highest point where it passes
through the roof and any other obstruction within a
horizontal distance of 18 in. (450 mm).

Flashing and storm collar installation

Flashings and storm collars are field supplied. Flashings
and storm collars suitable for Type B vent materials
(or better) may be used. To obtain flashings and storm
collars, please contact your local vent material supplier.
Follow the installation instructions supplied by the
manufacturer.
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