Sterling TD User Manual
Page 21

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VENTING (continued)
EXHAUST VENTING
N e v e r o p e r a t e s e p a r a t e d
combustion duct furnaces 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 (symptoms 
include grogginess, lethargy, inappropriate 
tiredness, or fl u-like symptoms).
1. In the United States, vent system installation must be
in accordance with the latest edition of ANSI Z223.1 
(NFPA 54) 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 Breidert Type L or Fields Starkap, furnished by the
customer, must be installed at the termination point 
of the vent system. See Figures 9A and 9B.
3. Each duct furnace 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 UL S636 
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.”
Never use pipe of a diameter other
than that specifi ed in Table 1! 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 (288°C).
6. The vent system must be installed to prevent
collection of condensate. Pitch horizontal pipes 
downward 1/4 inch per foot (21mm/m) towards the 
vent cap to facilitate drainage. Vertical vent pipes 
should be piped as depicted in Figure 9A.
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). Equivalent length equals the total length 
of straight pipe plus 10 feet (3.05m) for each 90 
degree elbow and 4 feet (1.22m) for each 45 degree 
elbow.
8. For horizontal combustion air systems longer than
5 feet (1.5m), the system must be supported from 
overheard building structures at 4 feet (1.22m) 
maximum intervals in the United States and at 3 feet 
(1m) maximum intervals in Canada.
9. The exhaust vent system must remain at a minimum
distance of 6 inch (152mm) 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.
For a VERTICAL vent pipe section that passes through 
a fl oor or roof, an opening 4 inch (102mm) greater in 
diameter is required. The opening must be insulated and 
fl ashed in accordance with applicable installation codes. 
Also see Figures 10A and 11A.
A HORIZONTAL section of an exhaust vent system that 
passes through a combustible wall must be constructed 
and insulated as shown in Figures 10B and 11B.
