Reznor EEDU Owner's manual

Revision: I-EEDU (02-21) 150492-A
INSTALLATION/OPERATION/MAINTENANCE FOR INDOOR
POWER-VENTED DUCT FURNACE
Supersedes: I-EEDU (02-17) PN150492R8
MODEL EEDU
⚠ 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.
• 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 neighbor’s phone. 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.

2I-EEDU (02-21) 150492-A
TABLE OF CONTENTS
GENERAL INFORMATION ...................................................................3
References ..............................................................................3
Important Safety Information.................................................................4
Warranty ................................................................................4
Installation Codes .........................................................................4
Unit Location .............................................................................5
Combustion Air Requirements ...............................................................5
Hazards of Chlorine........................................................................6
Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Clearances ..............................................................................8
Weights .................................................................................8
INSTALLATION ............................................................................9
Unpacking and Inspection...................................................................9
Pre-Installation Checklist....................................................................9
Pre-Installation Modifications ...............................................................10
High CFM Conversion ..................................................................10
Reverse Airflow Conversion ..............................................................12
Condensate Drain Installation ............................................................13
Coupling Additional Furnaces Together .....................................................13
Mounting Furnace ........................................................................16
Suspension-Mounting...................................................................16
Base-Mounting ........................................................................17
Piping Connections .......................................................................18
Gas Supply Pressure ...................................................................18
Gas Supply Piping .....................................................................18
Supply Piping Connections ..............................................................19
High Elevation (>2,000 Feet/609 Meters) Installations..........................................19
Conversion to LP (Propane)..............................................................21
Vent Connections ........................................................................21
Specific Venting Requirements ...........................................................21
Rotating Venter Outlet ..................................................................22
Vent Termination (Vent Pipe and Vent Cap) .................................................23
Vent Termination Clearances.............................................................26
Duct Connections ........................................................................27
Ductwork Requirements .................................................................27
Duct Furnace Airflow ...................................................................29
Duct Furnace Blower Connections.........................................................29
Bypass Duct Construction ...............................................................31
Ductwork-to-Furnace Connections.........................................................32
Electrical Connections.....................................................................33
FIELD-INSTALLED OPTIONS................................................................33
Discharge Air Temperature Sensor Installation..................................................33
Option AG3: Discharge Air Temperature Sensor Installation.....................................33
Option AG8, AG9, or AG15: Discharge Air Temperature Sensor Installation ........................34
Thermostat Installation ....................................................................36
Electrical Connections for Field-Installed Options................................................36

3
I-EEDU (02-21) 150492-A
Table 1. Related Technical Manuals Available from Factory Distributor
Type Form*PN
Replacement parts P-EEDU 263547
Optional hanger kit installation I-OPT-HK 98346
Replacement kit for discontinued fan control CP-Thermocore 1-FC 20918
Propane gas conversion CP-GC Parts 143147
*Also available at www.reznorhvac.com.
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.
References
TABLE OF CONTENTS—CONTINUED
CONTROLS ..............................................................................36
Combustion Air Proving Switch..............................................................36
Limit Switch .............................................................................37
Fan Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Gas Control Valve ........................................................................39
Optional Two-Stage Operation (Heating Only)................................................39
Optional Two-Stage Operation (Makeup Air) .................................................39
Optional Electronic Modulation............................................................40
Pilot and Ignition Systems..................................................................41
OPERATION .............................................................................43
Pre-Startup Checklist .....................................................................43
Startup.................................................................................43
Post-Startup Checklist.....................................................................44
ADJUSTMENTS...........................................................................44
Manifold Gas Pressure Measurement and Adjustment............................................44
Burner Air Adjustment (Propane Units Only)....................................................45
MAINTENANCE...........................................................................46
Service Checklist.........................................................................46
Maintenance Procedures ..................................................................46
Operating Gas Valve Maintenance ........................................................47
Burner Rack and Pilot Maintenance........................................................47
Heat Exchanger Cleaning ...............................................................49
Venter Maintenance ....................................................................50
TROUBLESHOOTING ......................................................................50
INSTALLATION RECORD (TO BE COMPLETED BY INSTALLER)...................................52

4I-EEDU (02-21) 150492-A
GENERAL INFORMATION—CONTINUED
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 EEDU duct furnace.
Warranty
Refer to the limited warranty form in the literature bag provided with the unit. The warranty is void if:
•Furnaces are used in atmospheres containing flammable vapors or atmospheres containing chlorinated or
halogenated hydrocarbons or any contaminant (silicone, aluminium oxide, etc.) that adheres to the spark ignition
flame sensing probe.
•Wiring is not in accordance with the diagram provided with the unit.
•Unit is installed without proper clearances to combustible materials or is located in a confined space without proper
ventilation and air for combustion (refer to Combustion Air Requirements and Clearances sections).
•Furnace air throughput is not adjusted within the range specified on the rating plate.
Installation Codes
•The unit is design-certified by the Canadian Standards Association for commercial/industrial use in both the United
States and Canada.
•The unit is approved for use with either natural gas or propane. The type of gas for which the furnace is equipped,
the correct firing rate, and electrical characteristics are shown on the unit rating plate.
•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 NFPA54/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.

5
I-EEDU (02-21) 150492-A
•Clearances from the heater and vent to 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 by continued operation of the heater.
•Special installations (aircraft hangars/garages): in the United States, installation in an aircraft hangar 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 in repair garages in accordance with
NFPA No. 88B (latest edition), Standard for Repair Garages. In Canada, installations in aircraft hangars, parking
garages, and repair garages should be in accordance with the requirements of the enforcing authorities and with
CSA B149.1 codes.
Unit Location
⚠ CAUTION ⚠
Do not locate the heater where it may be exposed to liquid spray, rain, or dripping water.
•A duct furnace is designed for connection to an inlet and an outlet duct and depends on an external air handler.
Location must be in accordance with Clearances section.
•There are a variety of factors such as system application, building structure, dimensions, and weight that contribute
to selecting the location. Read the installation information in this manual and select a location that complies with
the requirements.
Combustion Air Requirements
⚠ WARNING ⚠
The unit is designed to take combustion air from the space in which it is installed and is not
designed for connection to an outside combustion air intake duct. Connecting this furnace to an
outside combustion air intake duct voids the warranty and could cause hazardous operation.
•The unit is designed to take combustion air from the space in which it is installed. The air that enters into the
combustion process is vented to the outdoors. Sufficient air must enter the equipment location to replace the air
exhausted through the vent system.
•Modern construction methods involve a greater use of insulation, improved vapor barriers, and weather-stripping.
The result is that buildings are generally much tighter structurally than they have been in the past. The combustion
air supply for gas-fired equipment can be affected by these construction conditions because infiltration that would
have existed in the past may not be adequate. Extensive use of exhaust fans aggravates the situation. In the
past the filtration of outside air assumed in heat loss calculations (one air change per hour) was assumed to be
sufficient. However, current construction methods may now require the introduction of outside air into the room or
building through wall openings or ducts.
•Under all conditions, enough air must be provided to ensure there will not be a negative pressure condition within
the equipment room or space. A positive seal must be made in all return-air connections and ducts.
•Requirements for combustion air and ventilation air depend upon whether the unit is located in a confined or
unconfined space. A confined space is defined as a space whose volume is <50 cubic feet per 1,000 BTUh of the
installed appliance input rating. An unconfined space is defined as a space whose volume is ≥50 cubic feet per
1,000 BTUh of the installed appliance input rating.
•Even a slight leak can create a negative pressure condition in a confined space and can affect combustion. Do
not install a unit in a confined space without providing wall openings leading to and from the space. Depending
on the combustion air source, provide openings near the floor and ceiling for ventilation and air for combustion as
shown in Figure 1 and as listed in Table 2.
NOTE: For further details or other approved methods on supplying combustion air to a confined
space, refer to the National Fuel Gas Code ANSI Z223.1a (latest edition).

6I-EEDU (02-21) 150492-A
Figure 1. Confined Space Combustion Air Openings (Refer to Table 2)
Table 2. Determining Confined Space Combustion Air Requirements
Letter*Air Source Required Opening Size Calculate Combustion Air
Requirements
A Air inside building 1 square inch free area per 1000 BTUh Add total BTUh of all appliances in
confined space and divide by figures
at left for square inch free area size of
each (top and bottom) opening
Never <100 square inches free area for each opening
B Outside air through duct 1 square inch free area per 2000 BTUh
C Direct outside air 1 square inch free area per 4000 BTUh
*See Figure 1.
CONFINED
SPACE
A
AB
B
C
C
Hazards of Chlorine
⚠ CAUTION ⚠
The presence of chlorine vapors in the combustion air of gas-fired heating equipment presents
a potential corrosion hazard. Chlorine, 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 chlorine vapors from the combustion process. This may be done by wise location
of the furnace with regard to exhausters or prevailing wind direction.
•Remember, chlorine is heavier than air. This fact should be kept in mind when determining installation locations
of heating equipment and building exhaust systems.
Dimensions
Unit dimensions are shown in Figure 2 and listed in Table 3. All dimensions are in inches (mm).
GENERAL INFORMATION—CONTINUED
Combustion Air Requirements—Continued

7
I-EEDU (02-21) 150492-A
Figure 2. Unit Dimensions

8I-EEDU (02-21) 150492-A
Clearances
The unit must be installed so that clearances are provided for combustion air space, for service and inspection, and
for proper spacing from combustible construction. Clearance to combustibles is defined as the necessary minimum
distance from the heater to a surface or object that ensures that a surface temperature does not exceed 90°F above
the surrounding ambient temperature. Table 4 lists required clearances.
NOTE: The required service clearance is shown in Figure 2.
Weights
Unit weights are listed in Table 3.
GENERAL INFORMATION—CONTINUED
Dimensions—Continued
Table 3. Unit Dimensions
Unit
Size
Dimension (Inches (mm))*
A B C D E F
G
H J K L M
Natural
Gas
Units
Propane
Units
075,
100
35
( 889 )
14-1/4
( 362 )
35-11/16
( 906 )
14-5/8
( 371 )
4-3/8
( 111 )
3-15/16
( 100 )
1/2
( 13 )
1/2
( 13 )
5/8
( 16 )
12-1/2
( 318 )
7-1/4
( 184 )
7-7/16
( 189 )
4-5/8
( 117 )
125,
140
35
( 889 )
17
( 432 )
35-11/16
( 906 )
17-3/8
( 441 )
4-3/8
( 111 )
3-15/16
( 100 )
1/2
( 13 )
1/2
( 13 )
5/8
( 16 )
15-1/4
( 387 )
7-1/4
( 184 )
7-7/16
( 189 )
6
( 152 )
170 35
( 889 )
19-3/4
( 502 )
35-11/16
( 906 )
20-1/8
( 511 )
4-3/8
( 111 )
3-15/16
( 100 )
1/2
( 13 )
1/2
( 13 )
5/8
( 16 )
18
( 457 )
7-1/4
( 184 )
7-7/16
( 189 )
7-3/8
( 187 )
200 35
( 889 )
22-1/2
( 572 )
35-11/16
( 906 )
22-7/8
( 581 )
4-3/8
( 111 )
3-15/16
( 100 )
1/2
( 13 )
1/2
( 13 )
5/8
( 16 )
20-3/4
( 527 )
7-1/4
( 184 )
7-7/16
( 189 )
8-3/4
( 222 )
225 35-3/4
( 908 )
25-1/4
( 641 )
35-11/16
( 906 )
25-5/8
( 651 )
4-3/8
( 111 )
4-15/16
( 125 )
1/2
( 13 )
1/2
( 13 )
1-3/8
( 35 )
23-1/2
( 597 )
7-1/4
( 184 )
7-7/16
( 189 )
10-1/8
( 257 )
250 35-3/4
( 908 )
28
( 711 )
35-11/16
( 906 )
28-3/8
( 721 )
7-1/8
( 181 )
4-15/16
( 125 )
1/2
( 13 )
1/2
( 13 )
1-3/8
( 35 )
26-1/4
( 667 )
7-1/4
( 184 )
7-7/16
( 189 )
11-1/2
( 292 )
300 36
( 914 )
33-1/2
( 851 )
38-1/8
( 968 )
33-7/8
( 860 )
9-7/8
( 251 )
5-15/16
( 151 )
3/4
( 19 )
1/2
( 13 )
1-3/8
( 35 )
31-3/4
( 806 )
9-9/16
( 243 )
7-5/8
( 194 )
13-7/8
( 352 )
350 36
( 914 )
39
( 991 )
38-1/8
( 968 )
39-3/8
( 1000 )
12-5/8
( 321 )
5-15/16
( 151 )
3/4
( 19 )
1/2
( 13 )
1-3/8
( 35 )
37-1/4
( 946 )
9-9/16
( 243 )
7-5/8
( 194 )
16-5/8
( 422 )
400 36
( 914 )
44-1/2
( 1130 )
38-1/8
( 968 )
44-7/8
( 1140 )
15-3/8
( 391 )
5-15/16
( 151 )
3/4
( 19 )
1/2
( 13 )
1-3/8
( 35 )
42-3/4
( 1086 )
9-9/16
( 243 )
7-5/8
( 194 )
19-3/8
( 492 )
*See Figure 2.
Table 4. Required Clearances
Front Top Flue Connector Sides Bottom Rear
Required Clearance (Inches (mm))
6 (152) 12 (305) 29 (737)
Table 5. Unit Weights
Unit Size
075, 100 125 140 170 200 225 250 300 350 400
Net Weight (Pounds (kg))
104 (47) 126 (57) 128 (58) 150 (68) 172 (78) 194 (88) 216 (98) 262 (119) 306 (139) 328 (149)

9
I-EEDU (02-21) 150492-A
INSTALLATION
Unpacking and Inspection
•The unit was test-operated and inspected at the factory prior to crating and was in operating condition.
•If, upon removing it from its crate, the unit has been found to have incurred any damage in shipment, document
the damage with the transporting agency and contact an authorized Factory Distributor. If you are an authorized
Distributor, follow the FOB freight policy procedures.
⚠ CAUTION ⚠
Ensure that EXCESSIVE shipping vibration has not caused the burner rack assembly to drop off
the support rails into the bottom pan.
•Remove the panel from the bottom rear of the furnace (refer to Burner Rack and Pilot Maintenance section) and
check the burner rack assembly. The burner rack drawer should be setting level with each side on a support rail.
If the burner rack assembly is positioned properly, close the back panel.
•If the burner rack has fallen, remove the screws holding the burner rack assembly and pull out the burner rack
drawer. Reassemble by sliding the burner rack drawer into the heater, ensuring that both sides are resting on
the support rails. Reattach to the support brackets underneath the burners, reinsert the burner rack screws, and
close the back panel.
Pre-Installation Checklist
Check the rating plate for the gas specifications and electrical characteristics of the furnace to ensure that they
are compatible with the gas and electric supplies at the installation site.
Read this booklet and become familiar with the installation requirements of your particular furnace.
If you do not have knowledge of local requirements, check with the local gas company or any other local agencies
who might have requirements concerning this installation.
Before beginning, make preparations for necessary supplies, tools, and manpower.
Check to see if there are any field-installed options that need to be assembled/installed prior to unit installation.
Shipped-separate options could include a gas shutoff valve, a vent cap, a condensate drain fitting, a
thermostat, a hanger kit, a coupling kit, and/or a fan control.
Some gas control options will either have parts shipped loose with the unit or shipped separately. If the unit is
equipped with any of the options listed in Table 6, ensure that these parts are available at the installation site.
Table 6. Gas Control and Makeup Air Control Options
Type Option Included Components (PN)
Gas control (heating) AG7 Amplifier (260863), thermostat (48033)
Makeup air control*
AG3 Control switch (29054), gasket (7726), gasket retainer plate (7727)
AG8 Temperature sensor and mixing tube (48041), amplifier (260864), control switch (29054)
AG9 Remote temperature selector (48042), temperature sensor and mixing tube (48041), amplifier (260863),
control switch (29054)
AG15
Remote temperature selector (115848), stage adder module (115849), control switch (29054), 115-24V
(103055), 208/230-24V transformer (103497), 1/2-inch transformer locknut (16222), discharge sensor
holder (115850), discharge air sensor holder bracket (213612), temperature sensor (115815)
AG21
Signal conditioner (134170), conditioner relay (14747), 115-24V transformer (103055), 1/2-inch
transformer locknut (16222), fuse box (12697), fuse box cover (12698), hole plugs—quantity three
(16451)
*All of the makeup air options also require a shipped-separate fan control (option CQ1, PN 57960), which should be at the job site.

10 I-EEDU (02-21) 150492-A
INSTALLATION—CONTINUED
Pre-Installation Modifications
High CFM Conversion
This unit was factory assembled with the air throughput range listed on the rating plate. If the application requires
a higher CFM than listed on the rating plate, the unit may be converted for lower temperature rise and higher CFM.
The conversion will change the air throughput range as specified in Table 7. Verify the unit size on the heater rating
plate and, after confirming that this conversion is correct for the unit, perform the following procedure:
⚠ DANGER ⚠
• This conversion shall be done by a qualified service agency in accordance with the manufacturer’s
instructions and all applicable codes and requirements of the authority having jurisdiction. If the
information in these instructions is not followed exactly, a fire, an explosion, or the production
of carbon monoxide may cause property damage, personal injury, or loss of life. The qualified
service agency performing this work assumes responsibility for the conversion of this appliance
to provide for higher CFM.
• These instructions are designed to prepare the duct furnace for increased air throughput conversion
prior to installation. If your duct furnace is already installed, for your safety, turn OFF the gas and
electric supply before servicing.
NOTE: Before performing this conversion, determine if airflow is being reversed or if other field-
installed options apply. Perform desired procedure in accordance with Pre-Installation Modifica-
tions section.
1. Remove heat exchanger baffles (see Figure 3):
a. Remove support bracket screws and slide entire baffle assembly out of heat exchanger.
b. Reinstall screws to plug holes.
c. For unit sizes 075–100, conversion is complete. Proceed to step 3.
Table 7. High Air Throughput
Unit Size Minimum Maximum
CFM
075 855 2778
100 1140 3704
125 1425 4630
140 1595 5185
170 1937 6296
200 2279 7407
225 2564 8333
250 2849 9259
300 3175 11,111
350 3704 12,963
400 4233 14,815

11
I-EEDU (02-21) 150492-A
Figure 3. Heat Exchanger Baffle Removal
2. Remove side finger baffles on unit sizes 125–400 (see Figure 4):
NOTE: Do NOT remove the side finger baffles on unit sizes 075 and 100.
a. At entering air side of heat exchanger, locate side finger baffles and remove two side finger baffle screws
from each baffle.
b. Remove both side finger baffles.
BAFFLES
SUPPORT BRACKET SCREWS
Figure 4. Side Finger Baffle Removal
3. Install field conversion label (see Figure 5):
a. Fill in field conversion label (PN 263310) from literature bag.
b. Adhere label to unit on clean dry surface adjacent to rating plate.
4. Test unit for proper operation ensuring that air throughput is in accordance with Table 7.
SCREWS
SIDE FINGER BAFFLE
SCREWS
SIDE FINGER BAFFLE

12 I-EEDU (02-21) 150492-A
INSTALLATION—CONTINUED
Pre-Installation Modifications—Continued
High CFM Conversion—Continued
Figure 5. Field Conversion Label
Reverse Airflow Conversion
Duct furnaces are equipped with directional air baffles between the heat exchanger tubes. Facing the control
compartment of the furnace, the standard direction of airflow is from the rear of the furnace (gas valve location)
toward the front of the furnace. If the installation site requires airflow from the front to the rear, the unit may be field-
adapted by relocating the limit control and reversing the position of the directional air baffles as follows:
NOTE: When reversing airflow, the limit control MUST be relocated to the discharge end of the
heat exchanger.
1. Remove limit control (see Figure 6, DETAIL A):
a. If unit has optional outer side panels, locate limit control and remove outer side panel on that side of furnace.
b. Remove limit control bracket screws and remove limit control/bracket assembly. Do not disconnect limit control
wires.
c. Carefully pull limit control/bracket assembly through hole.
2. Reverse direction of airflow baffles (see Figure 6, DETAIL B):
a. Remove baffle screws and lift each airflow baffle slightly and slide forward. Remove all baffles from heat
exchanger.
b. Remove top baffle support screws and remove top baffle support. Reposition and secure support on opposite
end of heat exchanger using screws.
c. Remove bracket screws and remove bottom baffle support and bracket assembly. Reinstall bracket screws
to plug holes in heat exchanger bottom. Reposition bottom baffle support and bracket assembly on opposite
end of heat exchanger and secure using field-supplied sheet metal screws.
d. Reinstall airflow baffles removed in step 2a and secure using baffle screws.
3. Reinstall limit control removed in step 1:
a. Measure down 4-1/2 inches (114 mm) and across 1-11/16 inches (43 mm) at discharge end on same side of
heat exchanger. Using that center point, punch 2-1/4-inch (57-mm) diameter hole in side panel.
b. With limit control on heat exchanger side of bracket, slide limit control/bracket assembly through hole and
secure bracket using two sheet metal screws.
NOTE: If cable connections need to be moved, after the limit control is installed, secure them using
field-supplied sheet metal screws. Reinstall screws to plug all holes in the side panel.
c. Cover all original factory-made limit control holes using field-supplied sheet metal plate. Do not leave any
open holes in side panel or heat exchanger bottom. Unit is now ready for installation with airflow from front to
rear (gas valve side).
(date)
(name & address of company making this conversion)
263308

13
I-EEDU (02-21) 150492-A
Figure 6. Limit Control and Airflow Baffles
Condensate Drain Installation
Condensate can form in the heat exchanger of furnaces installed as makeup air units or when installed downstream
from a cooling coil. Under these conditions, a drain flange (option CS1, PN 31765) may be installed on the furnace
bottom as follows:
NOTE: A 4-inch (102-mm) minimum clearance is required under the furnace if a 90-degree street
elbow is used.
1. Install drain flange in bottom of furnace casing as shown in Figure 7 and secure using two machine screws (#10-
32 × 1-inch-long) and nuts.
2. Install 3/4-inch waste pipe nut in drain flange.
3. Seal all corners and four square holes in bottom pan edge using RTV sealant.
4. Terminate drain outside of building.
NOTE: Periodic cleaning of the condensate collector and disposal system is required.
LIMIT CONTROL/BRACKET ASSEMBLY
BRACKET
SCREWS
TOP BAFFLE
SUPPORT SCREWS
BAFFLE SCREWS
AIRFLOW BAFFLES
BOTTOM BAFFLE SUPPORT
DETAIL B
DETAIL A
TOP BAFFLE
SUPPORT
Figure 7. Condensate Drain
Coupling Additional Furnaces Together
Coupling of furnaces is done using optional coupling kits, which are listed in Table 8. Couple two, three, four, or five
furnaces together as follows. Item numbers in parentheses refer to Figure 8 and Table 9.
BOTTOM OF FURNACE CASING
MACHINE SCREW AND NUT
WASTE PIPE NUT
Table 8. Optional Furnace Coupling Kits
Option For Number of Units PN
CR1 2 57963
CR2 3 82654
CR3 4 82655
CR4 5 82656

14 I-EEDU (02-21) 150492-A
INSTALLATION—CONTINUED
Pre-Installation Modifications—Continued
Coupling Additional Furnaces Together—Continued
1. Position tie plate (1) below hanger angle (2) and secure tie plate to first furnace using threaded socket assemblies
(3). Tighten threaded socket assemblies firmly.
NOTE: The tie plate (1) MUST be under both hanger angles (2).
2. Position second furnace next to first furnace so that tie plate (1) is below hanger angle (2). Secure tie plate to
hanger angle using bolts (4), lockwashers (5), and nuts (6).
3. Position filler plates (7) as shown in Figure 8, DETAIL B. Using filler plate as template, drill 1/8-inch diameter
holes and secure filler plates using sheet metal screws (8). Offset of filler plate allows alignment with unit duct
flanges (see Figure 9).
Table 9. Coupling Kit Components
Item No. Component Description PN Quantity*
1 Plate Tie 57965 1
2 Angle Hanger — 2
3 Socket assembly Threaded 9557 2
4 Bolt Hex head, 3/8-16 × 1-1/4-inch-long 5095 2
5 Lockwasher Split ring 5197 2
6 Nut Spotweld — 2
7 Plate Filler 57964 2
8 Screw Sheet metal, #10 × 1/2-inch-long 11813 20
*Quantities listed are for option CR1 coupling kit (PN 57963) for two furnaces.
Figure 8. Coupling Kit Installation
7
1
7
UNIT 2
UNIT 1
4ʺ(102 mm)
1
3
4
5
6
2
DETAIL A DETAIL B

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Figure 9. Top View of Coupled Furnaces
NOTE: Refer to Figure 10 and Table 10 for coupled furnace front view dimensions.
ACCESS PANEL
LIMIT CONTROL
(DISCHARGE DUCT)
Figure 10. Front View of Coupled Furnaces
Table 10. Coupled Furnace Front View Dimensions
Unit Size Dimension A*
Inches Millimeters
075, 100 14-5/8 371
125, 140 17-3/8 441
170 20-1/8 511
200 22-7/8 581
225 25-5/8 651
250 28-3/8 721
300 33-7/8 860
350 39-3/8 1000
400 44-7/8 1140
*See Figure 10.
A
A + 2"
(51 mm)
LIMIT
CONTROL LIMIT
CONTROL
NOTE: Coupled units require access panels (see Figure 9) in the top or bottom of the outlet duct-
work for limit control service and observation of coupled units (refer to Duct Connections section).

INSTALLATION—CONTINUED
Mounting Furnace
⚠ WARNING ⚠
• Before installing the furnace, check the supporting structure to be used to verify that it has
sufficient load-carrying capacity to support the weight (refer to Weights section) of the unit.
• Service and combustion air clearances (refer to Clearances section) apply to both suspended
and mounted furnaces.
• The furnace must be level for proper operation. DO NOT place or add additional weight to a
suspended furnace.
Suspension-Mounting
•The furnace is provided with four 15/32-inch (12 mm) diameter holes for mounting using four-point suspension
as shown in Figure 11.
•The hardware required is shown in Figure 11, DETAIL A and includes four 7/16-16 threaded rods, four split ring
lockwashers, and eight 7-16 nuts.
•A hanger adapter kit (option CK3, PN 57959) with four free-turning threaded sockets for 1-inch pipe (see Figure
11, DETAIL B) is available.
•To determine the center line for the hangers, refer to dimension A listed in Table 10.
16 I-EEDU (02-21) 150492-A
Figure 11. Suspension-Mounting of Single Furnace
15/32-INCH HOLE
(SEE DETAIL A)
THREADED ROD
NUT
LOCKWASHER
NUT
THREADED SOCKET
DETAIL A DETAIL B
HANGER
BRACKET

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Base-Mounting
⚠ DANGER ⚠
When the furnace is base-mounted on combustible material, a minimum clearance of 12 inches
(305 mm) is required.The base or legs used for base-mounting must be made of non-combustible
material.
Base-mount the furnace as follows:
1. Remove two hanger brackets from their standard positions and install them at their base-mounting positions as
shown in Figure 12, DETAIL A.
2. Install four leg brackets (see Figure 12, DETAIL B) from base-mounting kit (PN 1034022). Secure leg brackets
with screws provided in existing holes in front. Drill new leg bracket holes in rear.
Figure 12. Base-Mounting Single Furnace
12 INCHES (305 mm)
10 INCHES (254 mm)
HANGER BRACKET
(STANDARD POSITION)
HANGER BRACKET
(BASE-MOUNTING POSITION)
DETAIL B
DETAIL A

18 I-EEDU (02-21) 150492-A
INSTALLATION—CONTINUED
Piping Connections
Gas Supply Pressure
The unit is equipped for a maximum gas supply pressure of 1/2 psi, 3.4 kPa, or 14 IN WC.
NOTES:
Supply pressure higher than 1/2 psi requires the installation of an additional service regulator
external to the unit.
PRESSURE TESTING SUPPLY PIPING
• Test pressures above 1/2 psi—disconnect the heater and manual valve from the gas supply line
to be tested. Cap or plug the supply line.
• Test pressures below 1/2 psi—before testing, close the manual valve on the heater.
Gas Supply Piping
⚠ DANGER ⚠
• All components of a gas supply system must be leak tested prior to placing equipment in service.
NEVER TEST FOR LEAKS WITH AN OPEN FLAME. Failure to comply could result in personal
injury, property damage, or death.
• Pipe joint compounds (pipe dope) shall be resistant to the action of liquefied petroleum gas or
any other chemical constituents of the gas being supplied.
•All piping must be in accordance with requirements outlined in the National Fuel Gas Code ANSI/Z223.1 (latest
edition) or CSA-B149.1 and B149.2 (refer to Installation Codes section).
•Gas supply piping installation shall conform with good practice and with local codes.
•Duct furnaces are orificed for operation with natural gas having a heating value of 1,000 (±50) BTU per cubic foot
or with propane gas having a heating value of 2,500 (±100) BTU per cubic foot. Sizing of gas supply lines depends
on piping capacity and is based on cubic feet per hour based on a 0.3 IN WC pressure drop, a 0.6 specific gravity
for natural gas at 1,000 BTU per cubic feet, and a 1.6 specific gravity for propane at 2,550 BTU per cubic feet. If
the gas at the installation does not meet this specification, consult the factory for proper orificing.
•Variables for sizing gas supply lines are listed in Table 11. When sizing supply lines, consider possibilities of future
expansion and increased requirements. Refer to National Fuel Gas Code for additional information on line sizing.
Table 11. Gas Supply Line Sizes
Length
of Pipe
(Feet)
Diameter of Pipe (Inches)
1/2 3/4 1 1-1/4 1-1/2 2
Natural
Gas Propane Natural Gas Propane Natural Gas Propane Natural Gas Propane Natural Gas Propane Natural Gas Propane
Cubic Feet per Hour
20 92 56 190 116 350 214 730 445 1100 671 2100 1281
30 73 45 152 93 285 174 590 360 890 543 1650 1007
40 63 38 130 79 245 149 500 305 760 464 1450 885
50 56 34 115 70 215 131 440 268 670 409 1270 775
60 50 31 105 64 195 119 400 244 610 372 1105 674
70 46 28 96 59 180 110 370 226 560 342 1050 641
80 43 26 90 55 170 104 350 214 530 323 990 604
90 40 24 84 51 160 98 320 195 490 299 930 567
100 38 23 79 48 150 92 305 186 460 281 870 531
125 34 21 72 44 130 79 275 168 410 250 780 476
150 31 19 64 39 120 73 250 153 380 232 710 433
175 28 17 59 36 110 67 225 137 350 214 650 397
200 26 16 55 34 100 61 210 128 320 195 610 372

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Figure 13. Supply Piping Connection
Supply Piping Connections
•Install a ground joint union and manual shutoff valve upstream of the unit control system, as shown in Figure 13.
•The 1/8-inch plugged tapping in the manual shutoff valve in Figure 13 provides connection for a supply line
pressure test gauge.
•The National Fuel Gas Code requires the installation of a trap with a minimum 3-inch drip leg (see Figure 13).
Local codes may require a drip leg longer than 3 inches (typically 6 inches). To permit burner removal, this drip
leg must extend beyond the edge of the heater.
•After all connections are made, disconnect the pilot supply at the control valve and bleed the system of air.
Reconnect the pilot line and leak-test all connections by brushing on a soap solution.
•Gas connection sizes are listed in Table 12.
Table 12. Gas Connection Sizes
Unit Size Natural Gas Propane
Connection (Inches)*
075–250 1/2 1/2
300–400 3/4 1/2
*Connection size to single-stage valve (not gas supply line size).
High Elevation (>2,000 Feet/609 Meters) Installations
NOTES:
• High elevation (>2,000 feet/609 meters) application with this unit depends on the installation
elevation and the heating value of the gas. At high elevations, the heating value of natural gas is
always lower than the heating value at sea level.
• Deration is necessary to compensate for low atmospheric pressure at high elevations. Generally
this will require obtaining the gas heating value from the local gas utility and replacing the burner
orifices.
For high elevation (>2,000 feet/609 meters) installations that require orifice replacement, replace the burner orifices
as follows:
1. Determine model number and rated input (BTUh) from unit’s rating plate.
2. Determine appropriate orifice replacement (refer to Table 13) for installation elevation.
3. Unthread existing gas orifices from gas manifold.

20 I-EEDU (02-21) 150492-A
INSTALLATION—CONTINUED
Piping Connections—Continued
High Elevation (>2,000 Feet/609 Meters) Installations—Continued
⚠ DANGER ⚠
• Do not use Teflon tape or pipe joint compound on the orifice threads. The hole in the orifice may
become blocked and may cause fire, explosion, property damage, carbon monoxide poisoning,
personal injury, or death.
• Use only using factory-supplied orifices. Do not attempt to drill out orifices in the field. Improperly
drilled orifices may cause fire, explosion, carbon monoxide poisoning, personal injury, or death.
4. Thread replacement gas orifices into gas manifold. To prevent cross-threading, hand-tighten orifices into gas
manifold until snug and then tighten one-half to one turn using wrench.
⚠ DANGER ⚠
DO NOT use an open flame to check for gas leaks.
Table 13. High Elevation Burner Orifices
Installation
Altitude (Feet)
Installation
Location Unit Size Natural Gas Propane
PN Orifice Size PN Orifice Size
2001–3000 US
075 16590 #46 39658 #56
100, 125 84437 #42 11834 #54
140, 170, 200, 225 45871 #39 9789 #53
250 87391 #40 9789 #53
300, 350, 400 87391 #40 11834 #54
2001–4500 Canada
075 84853 #47 63922 1.15 mm
100, 125 84437 #42 11834 #54
140, 170, 200, 225, 250 11792 #41 61652 1.45 mm
300, 350, 400 11792 #41 11834 #54
3001–4000 US
075 84853 #47 63922 1.15 mm
100, 125 84437 #42 11834 #54
140, 170, 200, 225 87391 #40 9789 #53
250 11792 #41 9789 #53
300, 350, 400 11792 #41 11834 #54
4001–5000 US
075 84853 #47 63922 1.15 mm
100, 125 84437 #42 11834 #54
140, 170, 200, 225, 250 11792 #41 61652 1.45 mm
300, 350, 400 11792 #41 11834 #54
5001–6000 US
075 84853 #47 63922 1.15 mm
100, 125 11828 #43 97360 1.35 mm
140, 170, 200, 225 11792 #41 61652 1.45 mm
250 84437 #42 61652 1.45 mm
300, 350, 400 84437 #42 11834 #54
6001–7000 US
075 40414 #48 40416 #57
100, 125 11828 #43 97360 1.35 mm
140, 170, 200, 225, 250 84437 #42 61652 1.45 mm
300, 350, 400 84437 #42 11834 #54
7001–8000 US
075 40414 #48 40416 #57
100, 125 11833 #44 11830 #55
140, 170, 200, 225 84437 #42 11834 #54
250, 300, 350, 400 11828 #43 11834 #54
8001–9000 US
075 39651 #49 40416 #57
100, 125 11833 #44 11830 #55
140, 170, 200, 225, 250 11828 #43 11834 #54
300, 350, 400 11828 #43 11830 #55