Sterling SF - Manual (Page 8)

8
EXHAUST VENTING
Never operate unit heaters without
combustion air and fl ue gas piping in place or severe
personal injury or death may occur!
1. Vent system installation must be in accordance
with the current National Fuel Gas Code-NFPA 54
or ANSI Z223.1 National Fuel Gas Code. In
Canada installation must be in accordance with
CSA-B149.1 “Installation Code for Natural Gas
Burning Appliances and Equipment” and
CSA-B149.2. “Installation Code for Propane
Burning Appliances and Equipment”.
2. A factory supplied Combustion Air Inlet Kit (which
includes a combustion air inlet box, air inlet screen,
defl ector disk, vent terminal and inlet air collar)
MUST be installed at the termination point of the
combustion air/vent system. See Figures 1a/1b,
2a/2b, and 4.
3. Each unit heater MUST have its own vent system.
It MUST NOT be connected to other vent systems
or to a chimney.
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.
5. Any run of single wall vent pipe passing through an
unheated space must be insulated with insulation
suitable to 550°F.
INSTALLATION (continued)
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.
7. The equivalent length of the vent system must
not be less than 5 feet (1.5m) and must not
exceed 50 feet (15.2m). The equivalent length
equals the total length of straight pipe plus
10 feet (3.05m) for each 90° elbow and 4 feet
(1.22m) for each 45° elbow.
8. Each joint must be secured with at least three
corrosion resistant screws. Two full turns of 3M
#425 Aluminum Foil tape or its equivalent must
then be used to seal each joint. High temperature
silicone sealant may be used instead of the tape.
Silicone sealant must be used to seal the joint
between the double wall vent pipe and the single
wall pipe.
9. 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.
10. 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.