Reznor SCE Owner's manual

Revision: SCE-IOM (01-22) 207697-B
MODEL SCE
INSTALLATION/OPERATION/MAINTENANCE FOR
SEPARATED-COMBUSTION PACKAGED FURNACE/BLOWER
Supersedes: I-SCE (04-21) 207697-A
⚠ DANGER ⚠
FIRE OR EXPLOSION HAZARD
• Failure to follow safety warnings exactly could result in serious injury, death, or property
damage.
• Improper installation,adjustment,alteration, service,or maintenance can cause serious injury,
death, or property damage.
• Installation and service must be performed by a qualified installer, service agency, or the gas
supplier.
• Be sure to read and understand the installation, operation, and service instructions in this
manual.
• Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or
any other appliance.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use any phone in your building.
• Leave the building immediately.
• Immediately call your gas supplier from a phone remote from the building. Follow the gas
supplier’s instructions.
• If you cannot reach your gas supplier, call the fire department.
DO NOT DESTROY. PLEASE READ CAREFULLY. KEEP IN A SAFE PLACE FOR FUTURE REFERENCE.

2SCE-IOM (01-22) 207697-B
TABLE OF CONTENTS
GENERAL INFORMATION ............................................................................. 3
References ........................................................................................ 4
Important Safety Information........................................................................... 4
Separated Combustion ............................................................................... 5
Installation Codes ................................................................................... 5
Special Installations (Aircraft Hangars/Garages) ........................................................... 5
Warranty .......................................................................................... 5
Dimensions ........................................................................................ 5
Weights........................................................................................... 7
Clearances ........................................................................................ 7
Location .......................................................................................... 7
Hazards of Chlorine ................................................................................. 7
INSTALLATION ...................................................................................... 8
Uncrating/Unpacking................................................................................. 8
Shipped-Separate Parts .............................................................................. 8
Suspension ........................................................................................ 9
Mounting .......................................................................................... 9
Duct Connections .................................................................................. 10
Requirements and Suggestions for Connecting and Installing Ducts ........................................ 11
Venting/Combustion Air Connections ................................................................... 12
Specific Venting Requirements: Piping ............................................................... 12
Specific Venting Requirements: Venter Outlet and Combustion Air Inlet Connections........................... 13
Specific Venting Requirements: Joints and Sealing ..................................................... 13
Specific Venting Requirements: Support.............................................................. 14
Specific Venting Requirements: Clearance ............................................................ 15
Specific Venting Requirements: Concentric Adapter Box ................................................. 15
Specific Venting Requirements: Concentric Adapter Box Pipe Connections .................................. 15
Vent Terminal Options............................................................................ 16
Vertical Vent Terminal (Option CC2) Installation........................................................ 17
Horizontal Vent Terminal (Option CC6) Installation...................................................... 22
Piping Connections................................................................................. 26
Gas Supply Pressure............................................................................. 26
Gas Supply Piping............................................................................... 27
Supply Piping Connections ........................................................................ 27
Condensate Drain Installation ...................................................................... 28
Electrical Connections .............................................................................. 29
Control Wiring .................................................................................. 29
CONTROLS ........................................................................................ 30
Thermostat ....................................................................................... 30
Combustion Air Proving Switch........................................................................ 30
Blower Fan Control ................................................................................. 31
Limit Control ...................................................................................... 31
Variable Frequency Drive ............................................................................ 31
Combination Gas Valve ............................................................................. 31
Optional Two-Stage Control (Heating Only Application)..................................................... 32
Optional Two-Stage Control (Makeup Air Application) ...................................................... 32
Optional Ductstat with Capillary Tubing (Option AG3) ................................................... 32
Optional Ductstat with Electronic Remote Setpoint Module (Option AG15 or AG16) ............................ 33
Optional Electronic Modulation ........................................................................ 33
Electronic Modulation Between 50% and 100% Firing Rate (Option AG7, AG8, or AG9) ........................ 33
Computer-Controlled Electronic Modulation Between 50% and 100% Firing Rate (Option AG21).................. 34
Electronic Modulation Between 20–28% and 100% Firing Rate (Option AG39) ................................ 34
Electronic Modulation Between 20–28% and 100% Firing Rate (Option AG40) ................................ 35

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SCE-IOM (01-22) 207697-B
GENERAL INFORMATION
•This unit has been tested for capacity and efficiency so as to provide many years of safe and dependable comfort
providing it is properly installed and maintained. With regular maintenance, this unit will operate satisfactorily year
after year. Abuse, improper use, and/or improper maintenance can shorten the life of the appliance and create
unsafe hazards.
•To achieve optimum performance and minimize equipment failure, it is recommended that periodic maintenance
be performed on this unit. The ability to properly perform maintenance on this equipment requires certain tools
and mechanical skills.
•This unit has been design-certified by the Canadian Standards Association to ANSI Standards and is available
for use with either natural or propane gas. The type of gas, the rate, and the electrical characteristics are on the
unit rating plate.
TABLE OF CONTENTS—CONTINUED
Pilot and Ignition Systems............................................................................ 37
Burners, Burner Orifices, and Carryover System .......................................................... 37
Dampers and Damper Controls ....................................................................... 38
Dirty Filter Switch .................................................................................. 39
OPERATION ....................................................................................... 39
Pre-Startup Checklist ............................................................................... 39
Startup .......................................................................................... 40
Post-Startup Checklist .............................................................................. 40
ADJUSTMENTS..................................................................................... 41
Belts, Blowers, and Drives ........................................................................... 41
Checking and Adjusting Belt Tension ................................................................ 41
Adjusting Blower Speed .......................................................................... 41
Reversing Blower Rotation ........................................................................ 42
Motor Load and Amp Adjustment ...................................................................... 42
Measure and Adjust Manifold (Outlet) Gas Pressure ....................................................... 43
High Elevation (>2,000 Feet/609 Meters) Installations ................................................... 44
Conversion to LP (Propane) ....................................................................... 45
Burner Air Shutter Adjustment ........................................................................ 46
Damper Linkage Adjustment.......................................................................... 46
Dirty Filter Switch Adjustment ......................................................................... 47
MAINTENANCE..................................................................................... 48
Service Checklist .................................................................................. 48
Maintenance Procedures ............................................................................ 48
Combination Gas Valve Maintenance ................................................................ 48
Vent/Combustion Air System Maintenance ............................................................ 49
Burner Rack Maintenance......................................................................... 49
Cleaning Pilot and Burners ........................................................................ 50
Spark Ignition System Maintenance ................................................................. 51
Maintenance Procedures—Continued .................................................................. 52
Cleaning Heat Exchanger ......................................................................... 52
Venter Motor Maintenance ........................................................................ 52
Air Circulation System Maintenance ................................................................. 52
Limit Control Check .............................................................................. 52
TROUBLESHOOTING ................................................................................ 52
INSTALLATION RECORD (TO BE COMPLETED BY INSTALLER)............................................. 56

4SCE-IOM (01-22) 207697-B
Table 1. Related Technical Manuals Available from Factory Distributor
Type Form*PN
Replacement parts SC-SCE-SSCBL-SSCDBL-RPL 269822
Vent/combustion air kit installation OPT-CC2-CC6 205892
Gas conversion OPT-GC 143147
*Also available at www.reznorhvac.com.
GENERAL INFORMATION—CONTINUED
References
Important Safety Information
Please read all information in this manual thoroughly and become familiar with the capabilities and use of your
appliance before attempting to operate or maintain this unit. Pay attention to all dangers, warnings, cautions, and
notes highlighted in this manual. Safety markings should not be ignored and are used frequently throughout to
designate a degree or level of seriousness.
DANGER: A danger statement describes a potentially hazardous situation that if not avoided, will result in severe
personal injury or death and/or property damage.
WARNING: A warning statement describes a potentially hazardous situation that if not avoided, can result in severe
personal injury and/or property damage.
CAUTION: A caution statement describes a potentially hazardous situation that if not avoided, can result in minor
or moderate personal injury and/or property damage.
NOTE: A note provides important information that should not be ignored.
⚠ DANGER ⚠
Gas-fired appliances are not designed for use in hazardous atmospheres containing flammable
vapors or combustible dust, in atmospheres containing chlorinated or halogenated hydrocarbons,
or in applications with airborne silicone substances.
⚠ WARNING ⚠
For your safety, read the warning labels on the unit.
NOTES:
• Installation should be done by a qualified agency in accordance with the instructions in this
manual and in compliance with all codes and requirements of authorities having jurisdiction.
• The instructions in this manual apply only to the model SCE blower-type unit heater with blower
cabinet.
• Model SCE units are not certified for residential use.

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SCE-IOM (01-22) 207697-B
Separated Combustion
•This separated-combustion unit is designed and manufactured in accordance with the ANSI definition of separated
combustion, which reads, “Separated Combustion System Appliance: A system consisting of an appliance and
a vent cap(s) supplied by the manufacturer, and (1) combustion air connections between the appliance and the
outside atmosphere, and (2) flue gas connections between the appliance and vent cap, of a type(s) specified by the
manufacturer but supplied by the installer, constructed so that, when installed in accordance with the manufacturer’s
instructions, air for combustion is obtained from the outside atmosphere and flue gases are discharged to the
outside atmosphere.”
•Separated-combustion units are designed to separate air for combustion and flue products from the environment
of the building in which the unit is installed. Separated-combustion appliances are recommended for use in dust-
laden and some corrosive-fume environments or in buildings with negative pressure (up to 0.15 IN WC). As the
definition states, all separated-combustion, power-vented equipment must be equipped with both combustion-air
and exhaust piping to the outdoors.
Installation Codes
•These units must be installed in accordance with local building codes. In the absence of local codes, in the United
States, the unit must be installed in accordance with the National Fuel Gas Code NFPA/ANSI Z223.1 (latest edition).
A Canadian installation must be in accordance with the CSA B149.1 Natural Gas and Propane Installation Code.
These codes are available from CSA Information Services, 1-800-463-6727. Local authorities having jurisdiction
should be consulted before installation is made to verify local codes and installation procedure requirements.
•These gas-fired products are certified by ANSI Z83 family of standards governing the safe usage of heating
equipment in the industrial/commercial marketplace. This includes using the heaters in makeup air applications to
supply corridor pressurization in commercial buildings such as office structures and apartment complexes.
•The heaters are not certified as residential heating equipment and should not be used as such.
•Clearances from the heater and vent to combustible construction or material in storage must conform with the
National Fuel Gas Code ANSI Z223.1 (latest edition) pertaining to gas-burning devices, and such material must
not attain a temperature over 160°F (71°C) by continued operation of the heater.
Special Installations (Aircraft Hangars/Garages)
Installations in aircraft hangars should be in accordance with NFPA No. 409 (latest edition), Standard for Aircraft
Hangars; in public garages in accordance with NFPA No. 88A (latest edition), Standard for Parking Structures; and
for repair garages in accordance with NFPA No. 88B (latest edition), Standard for Repair Garages. In Canada,
installations in aircraft hangars, repair garages, and parking garages should be in accordance with the requirements
of the enforcing authorities and in accordance with CSA B149 codes.
Warranty
Refer to the limited warranty information on the warranty card in the owner’s envelope. Warranty is void if:
a. Separated-combustion heaters are used in atmospheres containing flammable vapors or atmospheres containing
chlorinated or halogenated hydrocarbons or any contaminant (silicone, aluminum oxide, etc.) that adheres to
the spark ignition flame sensing probe.
b. Wiring is not in accordance with the diagram furnished with the heater.
c. Unit is installed without proper clearance to combustible materials.
Dimensions
All dimensions for the model SCE unit heater are shown in Figure 1 and are listed in Table 2.

6SCE-IOM (01-22) 207697-B
GENERAL INFORMATION—CONTINUED
Figure 1. Model SCE Dimensions in Inches (±1/8 (mm ±3))
STANDARD MODEL SCE
MODEL SCE WITH OPTIONAL HORIZONTAL INLET WITH DUCT FLANGES
Table 2. Dimensions
Dimension
(See Figure 1)
Unit Size
125 150, 175 200, 225 250 300 350 400
Inches ±1/8 (mm ±3)
A 32-1/4 (819) 35-1/4 (895)
B 25-1/4 (641) 30-3/4 (781) 36-1/4 (921) 43-1/2 (1105) 44-1/2 (1130) 50 (1270) 55-1/2 (1410)
D 15-1/4 (387) 20-3/4 (527) 26-1/4 (667) 33-1/2 (851) 34-1/2 (876) 40 (1016) 45-1/2 (1156)
E 8-1/8 (206) 10-3/4 (273) 9-3/4 (248) 10-3/4 (273)
F 16-1/4 (413) 21-3/4 (552) 27-1/4 (692) 34-1/2 (876) 35-1/2 (902) 41 (1041) 46-1/2 (1181)
G 7 (178) 10 (254) 9 (229) 10 (254)
H 17-3/4 (451) 23-1/4 (591) 28-3/4 (730) 36 (914) 37 (940) 42-1/2 (1080) 48 (1219)
J 17-3/8 (441) 22-7/8 (581) 28-3/8 (721) 35-5/8 (905) 38-5/8 (930) 42-1/8 (1070) 47-5/8 (1210)
K 17 (432) 18-3/8 (467) 17 (432) 16 (406) 17 (432) 18-3/8 (467) 17 (432)
L 1/2 (13) 3/4 (19)
M 40-1/4 (1022) 39 (991) 40-1/4 (1022) 39-1/4 (997) 40-1/4 (1022) 39 (991) 40-1/4 (1022)
N 27-3/4 (705) 30-3/4 (781)

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SCE-IOM (01-22) 207697-B
Clearances
Clearance to combustibles is defined as the minimum distance—from the heater to a surface or object—that is
necessary to ensure that a surface temperature of 90°F (50°C) above the surrounding ambient temperature is not
exceeded. For safety and convenience, ensure that the clearances listed in Table 4 are provide as shown in the
following table. Minimum clearances are also listed on the heater rating plate.
Table 3. Weights
Unit Size
125 150, 175 200, 225 250, 300 350 400
Net Weight (Pounds (kg))
313 (142) 358 (162) 382 (173) 482 (219) 498 (226) 560 (254)
Weights
Before installation, check the supporting structure to ensure that it has sufficient load-carrying capacity to support
the weight of the unit. Refer to Table 3, which lists unit weight based on unit size.
Location
⚠ CAUTION ⚠
Do not locate the heater where it may be exposed to water spray, rain, or dripping water.
•For best results, the heater should be placed with certain rules in mind. In general, a unit should be located from
8–12 feet (2.6–3.6 meters) above the floor. Units should always be arranged to blow toward or along exposed wall
surfaces, if possible. Where two or more units are installed in the same room, a general scheme of air circulation
should be maintained.
•Suspended heaters are most effective when located as close to the working zone as possible, and this fact should
be kept in mind when determining the mounting heights to be used. However, avoid directing the discharged air
directly on the room occupants.
•Partitions, columns, counters, or other obstructions should be taken into consideration when locating the unit heater,
so that a minimum quantity of airflow will be deflected by such obstacles. When units are located in the center of the
space to be heated, the air should be discharged toward the exposed walls. In large areas, units should be located
to discharge air along exposed walls with extra units provided to discharge air in toward the center of the area.
•At those points where infiltration of cold air is excessive, such as at entrance doors and shipping doors, it is
desirable to locate the unit so that it will discharge directly toward the source of cold air from a distance of 15–20
feet (4.5–6 meters).
Hazards of Chlorine
⚠ WARNING ⚠
SC series separated-combustion units are not designed or approved for use in atmospheres
containing flammable vapors or atmospheres highly-laden with chlorinated vapors.
Table 4. Clearances
Unit Surface Minimum Clearances (Inches (mm))
Top 6 (152)
Control side 6 (152) + width of unit
Side opposite controls 6 (152)
Bottom, to combustibles 6 (152)
Bottom, to noncombustibles 0 (0)

8SCE-IOM (01-22) 207697-B
GENERAL INFORMATION—CONTINUED
Hazards of Chlorine—Continued
NOTE: 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.
INSTALLATION
NOTE: Before installation,make preparations for necessary supplies,tools,and manpower.
Uncrating/Unpacking
•The furnace is shipped completely-assembled. Immediately upon uncrating, check the gas specifications and
electrical characteristics on the unit’s rating plate to be sure that they agree with the gas and electric supply at
the installation site.
•Check the unit for any damage that may have been incurred during shipment. If damage is found, document the
damage with the transporting agency and immediately contact your Distributor. If you are an authorized Distributor,
follow the FOB freight policy procedures.
NOTE: After removing the shipping clips that fasten the unit to the crate, it is required that the
bolts that attach the shipping clips be reinstalled for support.
•The bottom corners are fastened to the crate using angled shipping clips. Remove the bolts from the shipping
clips and remove the clips. Reinstall the bolts on the heater legs to support the corner leg and the heater bottom.
•To protect the unit during shipping, blower models have special supports that must be removed before installation.
Remove the special supports as follows:
• Blower support legs: Remove the blower support legs and screws.
• Motor shipping block: Remove the wooden block located under the motor bracket. Find the two rubber pads
shipped in the instruction envelope. Place these pads on the ends of the motor bracket bolts.
• Motor shipping plate: Units equipped with motors of 1-1/2 HP or less have a metal shipping plate attached between
the motor and the blower housing. The shipping plate must be removed and the plate and screws discarded. on
a unit factory-equipped with an optional belt guard, the belt guard must be removed to reach the shipping plate.
• Concentric adapter box: The concentric adapter box assembly in the venting/combustion air kit (option CC2
or CC6) is required on all separated-combustion models. Ensure that the concentric adapter box carton is at the
installation site (refer to parts list in Table 8 or Table 10).
Shipped-Separate Parts
Some gas control options have parts that are either shipped loose—with the heater—or shipped separate. Before
beginning installation, ensure that any shipped-separate parts ordered are available at the site. Shipped-separate
options could include a shutoff valve, a condensate drain kit, a thermostat, a remote console, a disconnect switch, or
high-temperature vent sealing tape. Also, if your unit is equipped with any of the gas control options listed in Table
5, ensure that these parts are available at the job site.

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SCE-IOM (01-22) 207697-B
Suspension
⚠ WARNING ⚠
Units must be level for proper operation. Do not place additional weight on or add additional weight
to the suspended unit.
The unit has four-point suspension (see hanger center line dimensions shown in Figure 1). At each suspension point,
the unit is factory-equipped with a free-turning, female, 1-inch NPT pipe hanger. Suspend the unit by connecting the
pipe hanger to a 1-inch threaded pipe. See Figure 2 for the standard and alternative suspension methods. The factory-
installed pipe hanger may be removed and the heater may be suspended as shown in the right view of Figure 2.
Figure 2. Suspension Methods
Mounting
NOTE: Support is required where furnace and blower cabinets meet.
•Model SCE requires six mounting support locations—three on each side—as shown in Figure 3.
Table 5. Shipped-Separate Parts for Gas Control Options
Application Option Part(s)
Heating AG7 Thermostat (PN 48033)
Makeup air
AG3 Control switch (PN 29054)
AG8 Control switch (PN 29054); sensor and mixing tube (PN 48041)
AG9 Control switch (PN 29054); remote temperature selector (PN 48042); sensor and mixing tube (PN 48041)
AG15,
AG16
Control switch (PN 29054); remote temperature selector (PN 115848); stage adder module (PN 115849); discharge
air sensor holder (PN 115850); discharge air sensor holder bracket (PN 213612); AG16 also includes temperature
display (PN 115852)
AG39 Remote temperature selector (PN 174849); temperature sensor (PN 133228); mixing tube (PN 90323)
NOTE: If an optional remote console is ordered, the control switch and temperature selector may be mounted on the console.
Figure 3. Support Locations

10 SCE-IOM (01-22) 207697-B
Figure 4. Corner Mounting Supports
Duct Connections
Refer to Table 6 for duct connection dimensions.
FIELD-FABRICATED
AVAILABLE AS A PA RT
INSTALLATION—CONTINUED
Mounting—Continued
•Supports (PN 74487) available from the manufacturer or field-fabricated legs, as shown in Figure 4, may be
used at the four corner support locations. Do not use this type of support at the center support locations between
the furnace and the blower section. At the center locations, a field-fabricated angle-iron brace support must
extend horizontally, jointly supporting a portion of both the furnace and the blower cabinet. All supports must be
noncombustible.
Table 6. Duct Connection Dimensions
Unit Size
125 150, 175 200, 225 250, 300 350 400
Dimension G (Inches (mm)*
15-1/4 (387) 20-3/4 (527) 26-1/4 (667) 34-1/2 (876) 40 (1016) 45-1/2 (1156)
*See Figure 5.
Figure 5. Duct Connection Dimensions

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SCE-IOM (01-22) 207697-B
Requirements and Suggestions for Connecting and Installing Ducts
• Type of ductwork: The type of duct installation to be used depends in part on the construction type of the roof—
whether wood or steel bar joist, steel truss, or pre-cast concrete—and the ceiling—whether hung, flush, etc.
• Ductwork material: Rectangular duct should be constructed of galvanized iron—not lighter than No. 26 US gauge
—or aluminum—No. 24 B&S gauge.
• Ductwork structure: All duct sections 24 inches (610 mm) or wider and over 48 inches (1,219 mm) in length
should be cross-broken on top and bottom and should have standing seams or angle-iron braces. Joints should
be S and drive strip or locked.
• Through masonry walls: No warm air duct should come in contact with masonry walls. Insulate around all air
duct through masonry walls with 1-inch (not less than 1/2-inch) of insulation.
• Through unheated space: Insulate all exposed warm air ducts passing through an unheated space with 1-inch
(not less than 1/2-inch) of insulation.
• Duct supports: Suspend all ducts securely from adjacent buildings members. Do not support ducts from unit
duct connections.
• Duct sizing: Proper sizing of the supply air ductwork is necessary to ensure a satisfactory heating installation. The
recognized authority for duct size is the Air Conditioning Contractor’s Association, 2800 Shirlington Road, Suite 300,
Arlington, VA 22206 (www.acca.org). A manual covering duct sizing in detail may be purchased directly from them.
⚠ CAUTION ⚠
To prevent possible motor overloading, ensure that the external duct system static pressure is
within the limits shown on the rating plate and that the motor pulley and belt are properly adjusted.
• Horizontal discharge duct length: To reduce losses at the furnace outlet, a minimum horizontal duct run of 24
inches (610 mm) is recommended before turns or branches are made in the duct system.
⚠ CAUTION ⚠
The joint where the supply air duct attaches to the furnace must be sealed securely to prevent
air leakage into draft hood or burner rack area. Leakage can cause poor combustion and pilot
problems, can shorten heat exchanger life, and can cause poor performance.
• Supply air duct/furnace horizontal connection: The seal between the furnace and the duct must be mechanical
using U-type flanges on the top and bottom of the connecting duct to to ensure tight joints and an airtight fit. Refer
to Figure 6 and perform the following steps:
a. Ensure that flanges on the furnace (heat exchanger) turn out as shown.
b. Shape duct connection as shown: U-type on top and bottom and L-type on sides.
c. Slide U-channels over furnace top and bottom flanges making connection.
d. Form U-channels to seal sides (see DETAIL A) and drill and lock with sheet metal screws.
• Access panels: Install removable access panels (see Figure 6) on both the upstream and downstream sides of
the furnace. The access panels must be accessible when the furnace is in service and should be a minimum of
6 ×10 inches (152 ×254 mm) in size so smoke or reflected light may be observed inside the casing to indicate
the presence of leaks in the heat exchanger. Ensure that the access panels are installed in such a manner so as
to prevent leakage.
• Return air duct/furnace connection: All return air ducts should be attached and sealed to the return air flanges
to provide airtight connections.
• Return air duct/grill size: Ensure that return air ducting or grills have a free area equal to the size of the return
duct connection.

12 SCE-IOM (01-22) 207697-B
INSTALLATION—CONTINUED
Duct Connections—Continued
Requirements and Suggestions for Connecting and Installing Ducts—Continued
DETAIL A
Figure 6. Connecting Ductwork to Furnace
Venting/Combustion Air Connections
⚠ 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 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 separated-combustion, power-vented units MUST BE equipped with both combustion air and exhaust piping
to the outdoors. The unique concentric adapter box designed for use with this heater allows for both combustion
air and exhaust piping with only one horizontal or vertical penetration hole in the building.
•These instructions apply to installation and use of the concentric adapter and vent/combustion air kit (option CC2
or CC6) designed for use with all Reznor separated-combustion products. The systems illustrated in this manual
are the only venting/combustion air systems approved for these separated-combustion units. Do not use this
concentric adapter box with any other products.
•Installation should be done by a qualified agency in accordance with these instructions. The service agency
installing this separated-combustion system is responsible for the installation.
Specific Venting Requirements: Piping
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.

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SCE-IOM (01-22) 207697-B
• 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 7.
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.
• 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.
Table 7. Pipe Diameter and Maximum Pipe Length from Heater to Concentric Adapter Box
Diameter/Length Unit Size
125–175 200–400
Diameters (Inches (mm))
Vent pipe 6 (152)
— 7 (178)
Inlet air pipe 6 (152)
— 7 (178)
Lengths (Feet (Meters))
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)
Specific Venting Requirements: Venter Outlet and Combustion Air Inlet Connections
⚠ DANGER ⚠
All separated-combustion units MUST BE equipped with both combustion air and exhaust piping
to the outdoors.
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 unit sizes 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.
Specific Venting Requirements: Joints and Sealing
Seal pipe joints as follows:
• To seal joints in Category III vent pipe: Follow the pipe manufacturer’s instructions for joining and sealing
Category III vent pipe sections.
• To seal joints in single-wall vent or combustion air pipe: Secure slip-fit pipe connections using sheet metal
screws or rivets. Seal all joints with aluminum tape or silicone sealant.
• To seal the joint in the terminal section of double-wall vent pipe (allowed ONLY ABOVE the concentric
pipes on a VERTICAL vent):Follow the pipe manufacturer’s instructions for joining and sealing double-wall
vent pipe sections.
• To seal the joint between the terminal section of double-wall vent pipe and the vent cap: Follow the illustrated
step-by-step instructions in Figure 7.
• To seal the joint between the terminal section of double-wall vent pipe and a single-wall or Category III
vent pipe: follow the illustrated step-by-step instructions in Figure 8. Make this connection no more than 6 inches
(152 mm) from the concentric adapter box.
NOTE: Pipes and vent caps may not look exactly as shown in the illustrations. Instructions apply
to both horizontal and vertical vent kits.

14 SCE-IOM (01-22) 207697-B
INSTALLATION—CONTINUED
Venting/Combustion Air Connections—Continued
Specific Venting Requirements: Joints and Sealing—Continued
Figure 7. Joining Double-Wall (Type B) Pipe to Vent Terminal Cap (Horizontal or Vertical)
Figure 8. Joining Double-Wall (Type B) Pipe to Single-Wall or Category III Vent Pipe
Using Tapered Reducer
Specific Venting Requirements: Support
Support horizontal runs every six feet (1.8 meters). Support vertical runs of Type B double-wall or Category III vent
pipe in accordance with the requirements of the pipe manufacturer. Support single-wall vertical pipe in accordance
with accepted industry practices. Do not rely on the heater or the adapter box for support of either horizontal or
vertical pipes. Use noncombustible supports on vent pipe.
NOTE: The double-wall vent terminal pipe does not attach to the concentric adapter box and must
be supported during installation.
STEP 1
Place a continual 3/8” bead of silicone sealant
around the circumference of the vent cap col-
lar. This will prevent any water inside the vent
cap from running down the double-wall pipe.
Do STEP 2 immediately following STEP 1.
STEP 2
Insert the collar on the vent cap inside the
inner wall of the double-wall pipe. Insert
as far as possible.Add additional silicone
sealant to fully close any gaps between
the vent cap and the double wall pipe.
This is necessary to prevent water from
entering the double wall pipe.
Secure the vent cap to the double-wall pipe by drilling and inserting a 3/4” long
sheetmetal screw into the vent cap collar. Do not overtighten screw.
STEP 3
STEP 1
On the taper-type reducer, place a con-
tinual 1/4” bead of silicone sealant
around the circumference.
STEP 2
Insert the collar of the reducer into the
inner pipe of the double-wall pipe until
the bead of sealant contacts the inner
pipe creating a sealed joint.
STEP 3
Spaced equally around the double-wall
pipe, drill three small holes below the
sealant ring. Insert 3/4 inch long
sheetmetal screws to secure the joint. Do
not overtighten screws.
5" I.D.
Double-
Wall
Pipe
6" to 5" or
7" to 5"
Taper-
Type
Reducer
DoSTEP 2
immediately
following
STEP1.

15
SCE-IOM (01-22) 207697-B
Specific Venting Requirements: Clearance
Do not enclose the vent pipe or place pipe closer than 6 inches (152 mm) to combustible material.
Specific Venting Requirements: Concentric Adapter Box
The concentric adapter box (PN 205885) is included in the vent/combustion air kit. Installation instructions depend
on whether the vent system is horizontal (option CC6) or vertical (option CC2). All separated-combustion installations
require a concentric adapter box as shown in Figure 9.
Figure 9. Concentric Adapter Box
Specific Venting Requirements: Concentric Adapter Box Pipe Connections
NOTE: Do NOT make actual connections until after reading the instructions and length require-
ments for installing the vent/combustion air kit. The connection requirements are the same for
both vertical and horizontal systems, but the length of the double-wall pipe will vary.
When pipe diameters differ, depending on direction of airflow, join the pipes with either a tapered reducer or enlarger
as shown in Figure 10.
View of Heater Connection Side
View of Vent Terminal Connection Side
Collar for connecting
indoor portion of the
combustion air pipe
Opening for
double-wall vent
pipe to pass
through the box.
Collar for
attaching outside
concentric portion
of the combustion
air pipe
Concentric Adapter Box Airow

16 SCE-IOM (01-22) 207697-B
INSTALLATION—CONTINUED
Venting/Combustion Air Connections—Continued
Specific Venting Requirements: Concentric Adapter Box Pipe Connections—Continued
Figure 10. Concentric Adapter Box Connections
Vent Terminal Options
Vent terminal options CC2 (vertical vent configuration) and CC6 (horizontal vent configuration) are shown in Figure 11.
UNIT SIZES 125–400 WITH 6-INCH PIPE BETWEEN FURNACE AND BOX
UNIT SIZES 200–400 WITH 7-INCH PIPE BETWEEN FURNACE AND BOX

17
SCE-IOM (01-22) 207697-B
Figure 11. Horizontal and Vertical Venting Options
Vertical Vent Terminal (Option CC2) Installation
•Field-supplied components required for installation of the horizontal vent kit are as follows:
a. Vent and combustion air piping in accordance with Table 7
b. Tapered vent pipe diameter reducers and/or increasers, as required
c. Thimble (not required if wall is of non-combustible construction)
d. Flashing
e. Sheet metal screws, tape, and sealant, as required
•Factory-supplied components for installation of the vertical vent kit are listed in Table 8.
VERTICAL (OPTION CC2) HORIZONTAL (OPTION CC6)
Figure 12. Option CC2 Components
EXHAUST VENT TERMINAL ASSEMBLY COMBUSTION AIR INLET ASSEMBLY
Table 8. Vertical Vent Terminal/Combustion Air Package (Option CC2) Components
PN Description Quantity
205896 Kit package 1
205885 Concentric adapter box (see Figure 9) 1
110052 Exhaust vent terminal assembly (see Figure 12) 1
53330 Combustion air inlet assembly (see Figure 12) 1
207232 Concentric adapter box bracket 2
53335 High-temperature silicone sealant, tube 1

18 SCE-IOM (01-22) 207697-B
INSTALLATION—CONTINUED
Venting/Combustion Air Connections—Continued
Vertical Vent Terminal (Option CC2) Installation—Continued
⚠ DANGER ⚠
• To prevent combustion products from entering the occupied space, all vent terminals must be
positioned or located away from fresh air intakes, doors, and windows. Failure to comply could
result in severe personal injury or death and/or property damage.
• Consider local snow depth conditions. The vent must be at least 6 inches (152 mm) above the
anticipated snow depth.
1. Determine vent terminal location on roof:
a. If more than one vertical vent terminal is being installed, minimum spacing between vent center lines is
determined by minimum outdoor design temperature (coldest outdoor condition at installation site). Refer to
Table 9 to ensure that location complies with minimum outdoor design temperature requirements.
b. Select location away from fresh air intakes, allowing space for concentric adapter box inside. Vent terminal
must be located away from adjacent buildings as shown in Figure 13.
2. Install vent pipe and combustion air pipe runs:
a. Connect piping to heater in accordance with specifications listed in Specific Venting Requirements: Piping
and Specific Venting Requirements: Venter Outlet and Combustion Air Inlet Connections sections.
b. Seal all joints in accordance with specifications listed in Specific Venting Requirements: Joints and Sealing
section. Due to high temperature considerations, do not enclose exhaust pipe or place pipe closer than 6
inches (152 mm) to combustible material.
c. Extend piping runs close to roof at location selected in step 1 and support piping in accordance with specifications
listed in Specific Venting Requirements: Support section.
NOTE: The vent pipe will extend through the roof after the concentric adapter box is installed.The
indoor combustion air pipe will end at the box.
3. Cut hole through outside wall for combustion air pipe.
a. Ensure that location and orientation of concentric adapter box are correct and mark and cut hole.
b. Ensure that hole accommodates 8-inch (203-mm) combustion air pipe. Thimble may be required depending
on wall construction and/or local codes. Larger diameter combustion air pipe serves as clearance for vent pipe
on non-combustible construction.
Table 9. Minimum Spacing Between Center Lines of Vertical Vent Pipes
Minimum Outdoor Design Temperature Minimum Spacing Between Center Lines of Vertical Vent Pipes
(Inches (mm))
≥31°F (≥0°C) 36 (914)
−10 to 30°F (−23 to −1°C) 60 (1524)
< −10°F (< −23°C) 84 (2134)

19
SCE-IOM (01-22) 207697-B
Shaded area represents
required continuous
(no joints) section of
vent pipe. Section of
pipe may extend higher.
Vent Pipe
Rear
View
Side View
Figure 13. Option CC2 Installation
4. Secure longer angles on concentric adapter box brackets (see Figure 14) to concentric adapter box.
NOTE: The longer angle of the concentric adapter box bracket has five 7/32-inch holes that allow
the position of the bracket on the box to be adjusted.
Figure 14. Concentric Adapter Box Brackets

20 SCE-IOM (01-22) 207697-B
INSTALLATION—CONTINUED
Venting/Combustion Air Connections—Continued
Vertical Vent Terminal (Option CC2) Installation—Continued
5. Connect outside section of combustion air pipe to concentric adapter box (see Figure 15):
a. Determine length of combustion air pipe so that dimension X in Figure 15 is equal to bracket length plus roof
thickness and plus anticipated snow depth. Ensure that length of combustion air pipe does not exceed 48
inches (1,219 mm) or does not extend less than 18 inches (457 mm) above roof.
b. Secure inlet air pipe to collar of concentric adapter box using sheet metal screws. Seal joint and seam using
tape or sealant.
Figure 15. Combustion Air Pipe Installation
6. Secure concentric adapter box to underside of roof (see Figure 15):
⚠ CAUTION ⚠
• If the roof is combustible, ensure that brackets are positioned to allow a 2-inch (51 mm) clearance
between the concentric adapter box and the roof.
• If any holes are made in the concentric adapter box in error, ensure that they are sealed.
a. Insert combustion air pipe through roof as shown in Figure 16.
b. Position concentric adapter box to match pipe runs and secure short angles of concentric adapter brackets
(see Figure 14) to underside of roof using field-supplied hardware.
c. Install field-supplied flashing around combustion air pipe on roof outside.