Sterling GG - Manual (Page 8)

VENTING (continued)
4. Use UL 1738 listed single wall pipe for the vent system.
For installations in Canada, use corrosion resistant
and gas-tight, listed vent pipe conforming with local
building codes, or in the absence of local building
codes, with current CSA-B149.1, Installation Codes
for Natural Gas Burning Appliances and Equipment
or CSA-B149.2, Installation Codes for Propane Gas
Burning Appliances and Equipment. For residential
installations in the United States, vent pipe approved
for Category III appliances must be used between the
appliance and the combustion air inlet box.
Never use pipe other than 4 inch
diameter. Never use PVC, ABS or any other non-
metallic pipe for venting! To do so may result in
serious damage to the unit and or severe personal
injury or death!
5. Any run of single wall vent pipe passing through an
unheated space must be insulated with an insulation
suitable to 550° F.
6. The vent system must be installed to prevent
collection of condensate. Pitch horizontal pipes
downward 1/4 inch per foot (21mm per meter) toward
the vent cap to facilitate drainage. Vertical vent pipes
should be piped as depicted in Figure 7.
7. The equivalent length of the vent system must not be
less than 5 feet (1.5m) and must not exceed 30 feet
(9m). The equivalent length equals the total length
of straight pipe plus 5 feet (1.5m) for each 90° elbow
and 2.5 feet (0.76m) for each 45° elbow.
8. For horizontal vent systems longer than 5 feet (1.5m),
the system must be supported from overhead building
structures at 4 foot (1.2m) intervals in the U.S. and at
3 foot (0.91m) intervals in Canada.
9. The exhaust vent system must remain at a minimum
distance of 1 inch (25mm) from all combustible
materials. Any part of the vent system that passes
through a combustible material must be properly
insulated.
NOTICE: Increasing the clearance distances may
be necessary if there is a possibility of distortion or
discoloration of adjacent materials.
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