Exhaust vent material - general
Use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenolsulfone) in
venting systems is prohibited. Do not use ABS or any cellular core pipe for exhaust venting.
3.7.4 Direct vent
Direct vent is a two-pipe system that draws combustion air (air intake) from outdoors, and
discharges exhaust gases to the outdoors. Ensure that adequate separation is maintained
between the air intake inlet and the exhaust vent terminal. Refer to the vent terminal
configuration drawings in the "Vent Termination" sections.
Flue gas exhaust to outdoors
Combustion air from outdoors. "Direct Vent" installation: check air intake outside is
clear of obstructions.
Figure 7 Direct vent
Air intake installation
At a new construction site, or during renovations, action must be taken to protect the boiler
from drywall dust or other construction related contaminants; combustion air should be drawn
from a clean source (e.g. outdoors) and the boiler should be isolated from interior dust
sources. Do not seal boiler case openings directly when firing (See Known contaminants on
page 9).
To Next Page
Loading...
Need help?
General
