16
VENTING
Figure 4.4: Direct Exhaust; Sidewall Venting
D. DIRECT EXHAUST; VERTICAL VENTING
1. This vent system will operate with a positive pressure
in the vent pipe. Follow vent pipe manufacturer’s
instructions for proper assembly of vent pipe and
fittings.
2. Refer to Table 4.2 for minimum and maximum vent
length allowed.
3. Maintain a minimum 2" (51 mm) clearance between
vent pipe and combustible construction.
4. Follow instructions under section C. DIRECT
EXHAUST; HORIZONTAL VENTING items 6b
through 6h.
5. Horizontal portions of the vent pipe shall slope
upward from the boiler towards the vertical vent not
less than 1/4" per foot (21 mm per meter).
Parties horizontales de l'évent doit pente ascendante
de la chaudière vers la cheminée verticale d'au
moins 1/4 "par pied (21 mm par mètre).
6. Provide a horizontal drain tee in the horizontal vent
run. Use silicone drain hose with a 3" (76 mm)
diameter loop trap with a water seal. Pipe to drain
per local codes.
7. Refer to vent pipe manufacturer’s instructions under
vertical venting section for recommendation for
penetration through floors and roofs.
8. Vent must terminate 12" (305 mm) above expected
snow lines.
9. See Figure 4.5 for details.
Figure 4.5: Direct Exhaust Vertical Venting
