Westinghouse Premium WBCMC 500 Series Installation, Start-Up, Maintenance, Parts, Warranty page 27

Figure 15 - Unbalanced Venting - Roof Exhaust and Sidewall Intake
NOTE: These drawings are meant to demonstrate system venting only.
The installer is responsible for all equipment and detailing required by
local codes.
Ensure the terminations are screened to prevent blockage caused by
debris or birds.
All vent pipes must be glued, properly supported, and the exhaust
pitched a minimum of 1/4" per foot back to the boiler to allow
drainage of condensate. When placing support brackets on vent
piping, the first bracket must be within 1 foot of the boiler and the
balance of 4 foot intervals on the vent pipe. Venting must be readily
accessible for visual inspection from the first three feet from the
boiler.
An unbalanced vent system can be installed ONLY when the exhaust
is in the vertical position. Failure to do so could result in serious
personal injury or death.
Take extra precaution to adequately support the weight of vent
pipes terminating through the roof. Failure to properly support roof
terminated vent piping could result in property damage, serious
personal injury, or death due to flue gas leakage.
Figure 16 - Roof and Sidewall Venting with Stainless Steel
whl-445 Rev. 000 Rel. 014 Date 7.21.20
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