Sterling SF - Manual (Page 7)

7
INSTALLATION (continued)
COMBUSTION AIR VENTING
Never operate unit heaters without
combustion air and fl ue gas piping in place or severe
personal injury or death may occur!
CARBON MONOXIDE!
Your venting system must not be blocked by any
snow, snow drifts, or any foreign matter. Inspect
your venting system to ensure adequate ventilation
exists at all times! Failure to heed these warnings
could result in Carbon Monoxide Poisoning (symp-
toms include grogginess, lethargy, inappropriate
tiredness, or fl u-like symptoms).
1. The combustion air system installation must be in
accordance with the current edition of the 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. The combustion air inlet box, inlet air screen,
defl ector disk, and vent terminal provided with the
unit heater 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 combustion
air system. It MUST NOT be connected to other
air intake systems.
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 5 or 6 inch
diameter with respective Combustion Air Inlet Kits.
Never use PVC, ABS or any other nonmetallic pipe
for venting! To do so may result in serious damage
to the unit and or severe personal injury or death!
5. Long runs of single wall combustion air piping
passing through an unheated space may require
insulating if condensation becomes noticeable.
6. The combustion air system must be installed to
prevent collection of condensate. Pitch horizontal
pipes downward 1/4 inch per foot (21 mm/m)
toward the inlet cap to facilitate drainage.
7. The equivalent length of the combustion air system
must not be less than 5 feet (1.5m) and must not
exceed 50 feet (15.2m). 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.
NOTICE: For optimum performance keep the com-
bustion air system as straight as possible.
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. General Electric RTV-108,
Dow-Corning RTV-732 or an equivalent silicone
sealant with a temperature rating of 500°F may
be used instead of the tape.
9. For horizontal combustion air 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.