10
I-SCE (09-18) PN207697R9
VENTING AND COMBUSTION AIR—CONTINUED
Hazards of Chlorine—Continued
Remember, chlorine is heavier than air. This fact should be kept in mind when determining the
installation location of heaters and building exhaust systems. The presence of chlorine vapors in the
combustion air of heating equipment presents a potential corrosion hazard. Chlorine, found usually in the form of
Freon or degreaser vapors, when exposed to flame will precipitate from the compound and form a solution with
any condensation present in the heat exchanger or associated parts. The result is hydrochloric acid, which readily
attacks all metals, including 300 grade stainless steel. Care should be taken to separate these vapors from the
combustion process. This may be done by wise location of the unit vent terminal and combustion air inlet with regard
to exhausters or prevailing wind directions.
Specific Venting Requirements: Piping
⚠ WARNING ⚠
Do not use an existing venting system. This heater requires installation of the combustion air/
vent system ordered with the unit (either Option CC2 or Option CC6). Vent installation to be
any listed vent system manufacturer. Do not intermix different vent system parts from different
manufacturers in the same venting system.
All pipe is field-supplied. Requirements for both the vent pipe and the combustion air inlet pipe are as follows:
• Vent Pipe: Vent pipe approved for a Category III appliance OR single-wall, 26-gauge or heavier galvanized (or a
material of equivalent durability and corrosion resistance) vent pipe is required between the heater and the concentric
adapter box. Double-wall (type B) vent pipe is required for the vent terminal section. The length of vent pipe that
extends through the box and runs concentric through the combustion air pipe must be one piece with no joints.
• Combustion Air Pipe: Sealed, single-wall galvanized pipe is recommended for combustion air.
• Pipe Length and Diameter: Vent pipe diameters and maximum indoor vent lengths apply to both horizontal and
vertical vents. Pipe diameter and length requirements listed for the indoor sections of pipe—between the heater
and the concentric adapter box—are listed in Table 5.
NOTE: Add all straight sections and equivalent lengths for elbows. The total length of the
straight sections and elbows must not exceed the maximum length.
Table 5. Pipe Diameter and Maximum Pipe Length from Heater to Concentric Adapter Box
Diameter/Length
Model
125–175 200–400
Diameters (Inches (mm))
Vent pipe
6 (152)
— 7 (178)
Inlet air pipe
6 (152)
— 7 (178)
Lengths (Feet (M))
Minimum 5 (1.5)
Maximum, 6-inch pipe 50 (15)
Maximum, 7-inch pipe — 70 (21)
Equivalent straight length for 45-degree elbow 4 (1.2)
Equivalent straight length for 90-degree elbow 8 (2.4)
• Outdoor Concentric Pipes Length and Diameter: The lengths of the outside (terminal) concentric pipes depend on
the installation. The diameters are 8 inches (203 mm) for the inlet air pipe and 5 inches (127 mm) for the vent pipe.
Specific Venting Requirements: Venter Outlet and Combustion Air Inlet Connections
Model SCE heaters have both an inlet air and a venter outlet connection. Both are 6 inches (152 mm) in diameter
for all unit sizes.
NOTE: If using 7-inch pipe on heater size 200–400, use a tapered 6- to 7-inch enlarger to attach
the vent pipe and a 7- to 6-inch reducer to attach the combustion air pipe.
To Next Page
Loading...
Need help?
General
