Trane VR104GD-U Series User manual

13.4 SEER2 / 81% AFUE
Single Package Gas Heating / Electric Cooling
(V)R104GD-U Ultra Low NOx Series
INSTALLATION INSTRUCTIONS
This product complies with SJVAPCD 4905 and SCAQMD 1111 with NOx levels below 14ng/J when operated on natural gas.
WARNING
DO NOT DESTROY THIS MANUAL. READ ALL INSTRUCTIONS IN THIS MANUAL AND
KEEP IN A SAFE PLACE FOR FUTURE REFERENCE.
FIRE OR EXPLOSION HAZARD
Failure to follow safety warnings exactly could result in serious injury, death, or property damage.
– 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 neighbors phone. Follow the gas suppliers instructions.
• If you cannot reach your gas supplier, call the fire department.
– Installation and service must be performed by a qualified installer, service agency or the gas
supplier.

2
TABLE OF CONTENTS
IMPORTANT SAFETY INFORMATION........................... 3
REQUIREMENTS & CODES ........................................... 4
GENERAL INFORMATION.............................................. 5
Before you install this unit.............................................. 5
Locating the Equipment................................................. 5
Heating Load ................................................................. 5
COMBUSTION AIR & VENTING REQUIREMENTS ....... 6
General Information....................................................... 6
Vent Termination ........................................................... 6
CIRCULATING AIR SUPPLY .......................................... 7
Air Ducts .................................................................... 7
Air Filter Requirements .............................................. 8
Unconditioned Spaces ............................................... 8
Acoustical Duct Work................................................. 8
UNIT INSTALLATION...................................................... 9
Packaging Removal....................................................... 9
Rigging & Hoisting ......................................................... 9
Clearances to Combustible Materials............................ 9
Rooftop .......................................................................... 9
Ground Level ................................................................. 9
Horizontal to Downflow Conversion............................... 9
Condensate Drain.......................................................... 9
ELECTRICAL WIRING .................................................... 10
Pre-Electrical Checklist.................................................. 10
Grounding...................................................................... 10
Line Voltage................................................................... 10
Thermostat / Low Voltage Connections......................... 11
Checking Heat Anticipator Settings ........................... 11
Blower Speed ................................................................ 11
5-Speed ECM Motor .................................................. 11
Optional Furnace Control Board Connections............... 11
Electronic Air Cleaner ................................................ 11
Humidifier................................................................... 12
GAS SUPPLY & PIPING.................................................. 12
Leak Check.................................................................... 12
High Altitude Conversion - Natural Gas......................... 12
START UP & ADJUSTMENTS ........................................ 13
Pre-Start Check List ...................................................... 13
Start-Up Procedure........................................................ 13
Air Circulation............................................................. 13
System Cooling.......................................................... 13
System Heating.......................................................... 14
Verifying & Adjusting Temperature Rise........................ 14
Verifying & Adjusting Firing Rate................................... 14
Manifold Pressure Adjustment....................................... 14
Verifying Over-Temperature Limit Control Operation .... 14
Verifying Burner Operation ............................................ 14
Verify Operation of the Supply Air Limit Switch ............. 15
OPERATING SEQUENCE............................................... 15
Heating Cycle ................................................................ 15
Cooling Cycle ................................................................ 15
Fan Mode ...................................................................... 15
EQUIPMENT MAINTENANCE......................................... 15
Heat Exchanger & Burner Maintenance ........................ 16
Lubrication ..................................................................... 16
Cleaning of Flame Sensor ............................................. 16
TROUBLESHOOTING..................................................... 17
FIGURES & TABLES....................................................... 18
Figure 10. Unit Dimensions........................................ 18
Table 5. Center of Gravity & Unit Shipping Weights .. 18
Airflow Data ................................................................... 19
Table 6. Nominal Heating Airflow Rates &
Temperature Rises (° F) .............................. 19
Table 7. Nominal Cooling Airflow Rates &
Temperature Rises (° F) .............................. 20
Gas Information ............................................................. 21
Table 8. Gas Pipe Capacities .................................... 21
Table 9. Gas Flow Rates ........................................... 21
Figure 11. Gas Valve Label ....................................... 22
Wiring Diagram & Electrical Data .................................. 23
Figure 12. Wiring Diagram for 230V / 60 Hz
Unit ........................................................... 23
Figure 13. Wiring Diagram for 230V / 60 Hz
Unit with ECM Outdoor Motor................... 24
Table 10. Electrical Data............................................ 25
FURNACE COMPONENTS ............................................. 26
Figure 14. Component Locations............................... 26
INSTALLATION CHECKLIST.......................................... 28
REPLACEMENT PARTS ................................................. 28

3
IMPORTANT SAFETY INFORMATION
Please read all instructions before servicing this equipment.
Pay attention to all safety warnings and any other special
notes highlighted in the manual. Safety markings are used
frequently throughout this manual to designate a degree or
level of seriousness and should not be ignored. WARNING
indicates a potentially hazardous situation that if not avoided,
could result in personal injury or death. CAUTION indicates a
potentially hazardous situation that if not avoided, may result
in minor or moderate injury or property damage.
WARNING:
ELECTRICAL SHOCK, FIRE OR
EXPLOSION HAZARD
Failure to follow safety warnings exactly could
result in serious injury, death, or property damage.
Improper servicing could result in dangerous
operation, serious injury, death or property
damage.
• Before servicing, disconnect all electrical power
to furnace.
• When servicing controls, label all wires prior to
disconnecting. Reconnect wires correctly.
• Verify proper operation after servicing.
WARNING:
These units are fully charged with R-410A refrigerant
and ready for installation. When a system is installed
according to these instructions, no refrigerant
charging is required. If repairs make it necessary for
evacuation and charging, it should only be attempted
by qualified, trained personnel thoroughly familiar
with this equipment. Some local codes require
licensed installation service personnel to service
this type of equipment. Under no circumstances
should the homeowner attempt to install and/or
service this equipment. Failure to comply with this
warning could result in equipment damage, personal
injury, or death.
WARNING:
Do not place combustible material on or against the
unit cabinet. Do not place combustible materials,
including gasoline and any other flammable vapors
and liquids, in the vicinity of the unit.
WARNING:
PROPOSITION 65 WARNING: This product contains
fiberglass wool, a product known to the state of
California to cause cancer. Disturbing the insulation
of this product during installation, maintenance, or
repair will expose you to fiberglass wool.
• Breathing this material may cause respiratory
irritations or may cause lung cancer.
• Fiberglass wool may also cause eye irritation,
skin sensitization, or other allergic responses in
susceptible individuals.
• Always wear goggles, disposable gloves, long
sleeved shirt, and appropriate breathing protection
when working near this insulation. If contact with
skin occurs, wash immediately with soap and water.
In case of contact with eyes, flush immediately with
water for at least 15 minutes. Contact a physician
if needed.
WARNING:
The information listed below and on the next page
must be followed during the installation, service,
and operation of this unit. Unqualified individuals
should not attempt to interpret these instructions
or install this equipment. Failure to follow safety
recommendations could result in possible damage
to the equipment, serious personal injury or death.
• Before beginning the installation, verify that the unit model
is correct for the job. The unit model number is printed on
the data label. Follow all precautions in the literature, on
tags, and on labels provided with the equipment. Read and
thoroughly understand the instructions provided with the
equipment prior to performing the installation and operational
checkout of the equipment.
• Never test for gas leaks with an open flame. Use
a commercially available soap solution to check all
connections. See page 12.
• Installation of equipment may require brazing operations.
Installer must comply with safety codes and wear appropriate
safety equipment (safety glasses, work gloves, fire
extinguisher, etc.) when performing brazing operations.
• This equipment is NOT to be used for temporary heating
of buildings or structures under construction.
• Use caution when handling this appliance or removing
components. Personal injury can occur from sharp metal
edges present in all sheet metal constructed equipment.
• Follow all precautions in the literature, on tags, and on
labels provided with the equipment. Read and thoroughly
understand the instructions provided with the equipment
prior to performing the installation and operational checkout
of the equipment.
• The installer should become familiar with the units wiring
diagram before making any electrical connections to the
unit. See the unit wiring label or Figure 12 (page 23) and
Figure 13 (page 24).

4
REQUIREMENTS & CODES
• This equipment must be installed in accordance with
instructions outlined in this manual, all applicable local
building codes, and the current revision of the National
Fuel Gas Code (NFPA54/ANSI Z223.1) or the Natural
Gas and Propane Installation Code, CAN/CGA B149.1.
• All electrical wiring must be completed in accordance with
local, state and national codes and regulations and with the
National Electric Code (ANSI/NFPA 70) or in Canada the
Canadian Electric Code Part 1 CSA C.22.1.
• The installer must comply with all local codes and regulations
which govern the installation of this type of equipment.
Local codes and regulations take precedence over any
recommendations contained in these instructions. Consult
local building codes and the National Electrical Code (ANSI
CI) for special installation requirements.
• This equipment contains liquid and gaseous refrigerant
under high pressure. Installation or servicing should only be
performed by qualified trained personnel thoroughly familiar
with this type equipment.
• Install this unit only in a location and position as specified
on Figure 1 (page 5). This unit is designed only for
outdoor installations and should be located with consideration
of minimizing the length of the supply and return ducts.
Consideration should also be given to the accessibility of
fuel, electric power, service access, noise, and shade.
• Air Ducts must be installed in accordance with the standards
of the National Fire Protection Association “Standards for
Installation of Air Conditioning and Ventilation Systems”
(NFPA 90A), “Standard for Installation of Residence Type
Warm Air Heating and Air Conditioning Systems” (NFPA
90B), these instructions, and all applicable local codes.
• Consult Table 7 (page 20), Table 8 (page 21), and the rating
plate for the proper circulating air flow and temperature
rise. It is important that the duct system be designed to
provide the correct flow rates and external pressure rise.
An improperly designed duct system can result in nuisance
shutdowns, and comfort or noise issues.
• Use only with the type of gas approved for this unit. Refer
to the unit rating plate.
• Provide adequate combustion and ventilation air to the unit.
See page 6 & page 7.
• Provide adequate clearances around the combustion air
intake louvers. See Figure 1.
• Combustion products must be discharged outdoors. Connect
this unit to an approved vent system only, as specified on
page 6 & page 7.
• The information listed below is for reference purposes only
and does not necessarily have jurisdiction over local or state
codes. Always consult with local authorities before installing
any gas appliance.
Combustion & Ventilation Air
• US: National Fuel Gas Code (NFGC), Air for Combustion
and Ventilation
• CANADA: Natural Gas and Propane Installation Codes
(NSCNGPIC), Venting Systems and Air Supply for
Appliances
Duct Systems
• US and CANADA: Air Conditioning Contractors Association
(ACCA) Manual D, Sheet Metal and Air Conditioning
Contractors National Association (SMACNA), or American
Society of Heating, Refrigeration, and Air Conditioning
Engineers (ASHRAE) Fundamentals Handbook
Electrical Connections
• US: National Electrical Code (NEC) ANSI/NFPA 70
• CANADA: Canadian Electrical Code CSA C22.1
Gas Piping & Gas Pipe Pressure Testing
• US: NFGC and National Plumbing Codes
• CANADA: NSCNGPIC
General Installation
• US: Current edition of the NFGC and the NFPA 90B. For
copies, contact the National Fire Protection Association Inc.,
Batterymarch Park, Quincy, MA 02269; or American Gas
Association, 400 N. Capitol, N.W., Washington DC 20001
or www.NFPA.org
• CANADA: NSCNGPIC. For a copy, contact Standard Sales,
CSA International, 178 Rexdale Boulevard, Etobicoke
(Toronto), Ontario, M9W 1R3 Canada
Safety
• US: (NFGC) NFPA 54–1999/ANSI Z223.1 and the Installation
Standards, Warm Air Heating and Air Conditioning Systems
ANSI/NFPA 90B.
• CANADA: CAN/CGA-B149.1 and .2–M00 National Standard
of Canada. (NSCNGPIC)

5
GENERAL INFORMATION
This single package gas heating / electric cooling unit is
designed only for outdoor rooftop or ground level slab
installations and can be readily connected to the high static duct
system of a home. This unit has been tested for capacity and
efficiency in accordance with AHRI standards and will 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.
Before you install this unit
√The cooling load of the area to be conditioned must be
calculated and a system of the proper capacity selected. It is
recommended that the area to be conditioned be completely
insulated and vapor sealed.
√Check the electrical supply and verify the power supply is
adequate for unit operation. Consideration should be given
to availability of electric power, service access, noise, and
shade. If there is any question concerning the power supply,
contact the local power company.
√All units are securely packed at the time of shipment and
upon arrival should be carefully inspected for damage prior
to installing the equipment at the job site. Claims for damage
(apparent or concealed) should be filed immediately with
the carrier.
√Survey the job site to determine the best location for setting
the unit. Choose an appropriate location that minimizes the
length of the supply and return air ducts.
√Please consult your dealer for maintenance information
and availability of maintenance contracts. Please read all
instructions before installing the unit.
Locating the Equipment
• Clearance in accordance with local installation codes, the
requirements of the gas supplier and the manufacturer’s
installation instructions.
• Dégaugement conforme aux codes d’installation locaux,
aux exigences du fournisseur de gaz et aux instructions
d’installation du fabricant.
• A clearance of at least 36 inches from the blower access
panel and from the louvered control access panel is
recommended for servicing and maintenance. Where
accessibility to combustibles clearances are greater
than minimum clearances, accessibility clearances
must take preference.
• Select a solid, level position, preferably on a concrete slab,
slightly above the grade level, and parallel to the home. DO
NOT PLACE UNIT UNDER THE HOME.
• Overhead obstructions, poorly ventilated areas, and areas
subject to accumulation of debris should be avoided. Do not
place the unit in a confined space or recessed area where
discharge air from the unit to re-circulate into the condenser
air inlet, through the coil.
• Sufficient clearance for unobstructed airflow through the
louvered control access panel and outdoor coil must be
maintained in order to achieve rated performance. See
Figure 1 for minimum clearances to obstructions.
• The hot condenser air must be discharged up and away from
the home, and if possible, in a direction with the prevailing
wind.
• If practical, place the air conditioner and its ducts in an area
where they will be shaded from the afternoon sun, when
the heat load is greatest.
Heating Load
This unit should be sized to provide the design heating
load requirement. Heating load estimates can be made
using approved methods available from Air Conditioning
Contractors of America (Manual J); American Society of
Heating, Refrigerating, and Air Conditioning Engineers; or other
approved engineering methods. For installations above 2,000
ft., the unit should have a sea level input rating large enough
that it will meet the heating load after deration for altitude.
Minimum Required
Clearances to Combustibles
36"
36"
36"
TOP OF UNIT
TO BE
UNOBSTRUCTED
1"
Figure 1. Clearance Requirements

6
COMBUSTION AIR & VENTING REQUIREMENTS
General Information
WARNING:
Installation methods other than those described in
the following sections must comply with the National
Fuel Gas Code and all applicable local codes for
providing sufficient combustion air to the unit.
• Provisions must be made during the installation of this unit
that provide an adequate supply of air for combustion.
• Instructions for determining the adequacy of an installation
can be found in the current revision of the NFGC (ANSI
Z223.1 / NFPA54). Consult local codes for special
requirements. These requirements are for US installations
as found in the NFGC.
• The requirements in Canada (B149.1) are structured
differently. Consult with B149.1 and local code officials for
Canadian installations.
WARNING:
Combustible air must not be drawn from a
contaminated atmosphere. Excessive exposure to
contaminated combustion air will result in safety
and performance related problems.
• To maximize heat exchanger life, the combustion air
must be free of chemicals that can form corrosive acidic
compounds in the combustion gases. The recommended
source of combustion air is to use clean air from outside.
DO NOT place any chemicals with flammable or caustic
vapors or these other corrosive chemicals near the vent
termination:
• Gasoline/Kerosene
• Permanent wave solutions
• Chlorinated waxes and cleaners
• Chlorine based swimming pool chemicals
• Water softening chemicals
• De-icing salts or chemicals
• Carbon tetrachloride
• Halogen type refrigerants
• Cleaning solvents
• Cements, glues, paint removers, varnishes, etc.
• Hydrochloric acid
• Masonry acid washing materials
• Plumbing Stack
Vent Termination
This unit has been equipped with an integral venting system
and designed to operate only with this venting system. No
additional venting shall be used. This unit must be vented to
the outdoors.
WARNING:
This unit is intended for outdoor installation only.
Do not vent the unit through a conventional venting
system.
A vent cover assembly has been supplied with the unit. and
can be found secured to the gas controls within the control
area of this unit. The vent cover assembly must be installed
to assure proper operation of the unit.
WARNING:
CARBON MONOXIDE POISONING HAZARD
Failure to follow the steps outlined below for
each appliance connected to the venting system
being placed into operation could result in carbon
monoxide poisoning or death.
The following steps shall be followed with each
individual appliance connected to the venting
system being placed in operation, while all other
appliances connected to the venting system are
not in operation:
1. Seal any unused openings in the venting system.
2.Inspect the venting system for proper size and
horizontal pitch, as required in the National Fuel
Gas Code, ANSI Z223.1/NFPA 54 or the CSA
B149.1, Natural Gas and Propane Installation
Codes and these instructions. Determine that
there is no blockage or restriction, leakage,
corrosion and other deficiencies which could
cause an unsafe condition.
3.As far as practical, close all building doors
and windows and all doors between the space
in which the appliance(s) connected to the
venting system are located and other spaces
of the building.
4.Close fireplace dampers.
5.Turn on clothes dryers and any appliance not
connected to the venting system. Turn on
any exhaust fans, such as range hoods and
bathroom exhausts, so they are operating at
maximum speed. Do not operate a summer
exhaust fan.
6.Follow the lighting instructions. Place the
appliance being inspected into operation.
Adjust the thermostat so appliance is operating
continuously.
7.Test for spillage from draft hood equipped
appliances at the draft hood relief opening after
5 minutes of main burner operation. Use the
flame of a match or candle.
8.If improper venting is observed during any of
the above tests, the venting system must be
corrected in accordance with the National Fuel
Gas Code, ANSI Z223.1/NFPA 54 and/or CSA
B149.1, Natural Gas and Propane Installation
Codes.
9.After it has been determined that each appliance
connected to the venting system properly vents
when tested as outlined above, return doors,
windows, exhaust fans, fireplace dampers and
any other gas-fired burning appliance to their
previous conditions of use.

7
Figure 2. Vent Assembly
Figure 2 shows the proper installation of the vent cover
assembly over the vent outlet on the exterior of the corner
panel. The fasteners used to secure the vent cover assembly
have been included in the owner’s package. The following
list summarizes the requirements for the location of the vent
system termination:
• The location of the vent termination must be consistent
with the National Fuel Gas Code (ANSI Z223.1) or CAN/
CGA-B149 Installation Codes.
• The vent termination must be located at least 4 feet
horizontally from any electric meters, gas meters, regulators,
and relief equipment.
• The vent termination must be located at least 3 feet above
any forced air inlet located within 10 feet.
• The vent termination must be located at least 4 feet below,
4 feet horizontally from, or 1 foot above any door, window,
or gravity air inlet into any building.
• The vent termination must be located at least 1 foot above
grade.
• The unit should be installed in a way that prevents any
obstruction of the vent termination during accumulating
snow.
• The unit installation shall avoid areas where condensate
drainage may cause problems by dropping on planters or
patios, etc. Also verify exhaust gases will not impinge on
windows or building surfaces, which may be compromised
or damaged by condensation.
• Do not install the unit such that exhaust from the vent
termination is directed into window wells, stairwells, under
decks, or in alcoves or similarly recessed areas. The vent
termination must not be located above any public walkways.
CIRCULATING AIR SUPPLY
WARNING:
Products of combustion must not be allowed to
enter the return air ductwork or the circulating air
supply. Failure to prevent products of combustion
from being circulated into the living space can create
potentially hazardous conditions including carbon
monoxide poisoning that could result in personal
injury or death.
All return ductwork must be adequately sealed, all
joints must be taped, and the ductwork must be
secured to the unit with sheet metal screws. When
return air is provided through the bottom of the unit,
the joint between the unit and the return air plenum
must be air tight.
The roof curb or cement pad on which the unit is
mounted must provide sound physical support of
the unit with no gaps, cracks, or sagging between
the unit and the curb or pad.
Return air and circulating air ductwork must not
be connected to any other heat producing device
such as a fireplace insert, stove, etc. Doing so may
result in fire, explosion, carbon monoxide poisoning,
personal injury, or property damage.
Air Ducts
This unit is designed only for use with a supply and return
duct. Air ducts should be installed in accordance with
the standards of the National Fire Protection Association
“Standard for Installation of Air Conditioning Systems” (NFPA
90A), “Standard for Installation of Residence Type Warm Air
Heating and Air Conditioning Systems” (NFPA 90B), and all
applicable local codes. NFPA publications are available by
writing to: National Fire Protection Association, Batterymarch
Park, Quincy, ME 02269 or visit www.NFPA.org on the web.
• Design the duct work according to Manual D by the Air
Conditioning Contractors of America (ACCA).
• The ducts must be properly sized not to exceed 0.30 inches
WC pressure drop per 100 feet of equivalent duct at 400
SCFM per nominal ton of cooling capacity.
• Duct work should be attached directly to the unit flanges
for horizontal applications.
• If roof curb is installed, the ducts must be attached to the
curb duct supports, not the unit.
• It is recommended that the outlet duct be provided with a
removable access panel. The opening should be accessible
when the unit is installed in service and shall be sizes so that
smoke or reflected light may be observed inside the casing
to indicate the presence of leaks in the heat exchanger. The
cover for the opening shall be attached in a way that will
prevent leaks.
• If outside air is utilized as return air to the unit for ventilation
or to improve indoor air quality, the system must be designed
so that the return air to the unit is not less than 50° F (10°
C) during heating operation.

8
Air Filter Requirements
Air Filter An air filter is not supplied with this package unit as
shipped from the factory. The installer must provide a high
velocity filter that is appropriately sized to the return air duct
opening or internal filter rack. The filters must comply with
ANSI/UL 900 or CAN/ULC-S111.
WARNING:
Never operate the unit without a filter in place.
Dust and lint could accumulate on internal parts,
resulting in loss of efficiency, equipment damage
and possible fire.
NOTE TO INSTALLER: After installing or replacing the filtration
system for this unit, add the following statement on or adjacent
to the filter service panel: “Replace filter(s) installed in your
system only with the same dimensional size filters that
are being replaced.”
• A suitable air filter must be installed upstream of the
evaporator coil of the return air system. Refer to Table 1
for recommended external filter sizes.
• All return air must pass through the filters before entering
the evaporator coil. It is important that all filters be kept
clean and replaced frequently to ensure proper operation
of unit. Dirty or clogged filters will reduce the efficiency of
the unit and result in unit shutdowns.
• Air filter pressure drop must not exceed 0.08 inches WC.
Table 1. Recommended External Air Filter Sizes
EXTERNAL FILTER SIZES
NOMINAL COOLING
(TONNAGE)
FILTER SIZE
(IN. X IN.)
APPROXIMATE AIR FLOW
RANGE (CFM)
APPROXIMATE FILTER
AREA (SQ. IN.)*
2.0 20 x 25 600-900 450
2.5 20 x 30 750-1200 550
3.0 25 x 25 1100-1300 625
3.5 24 x 30 1200-1600 750
4.0 18 x 24 (2 required) 1400-1800 850
5.0 20 x 25 (2 required) 1700-2200 1000
INTERNAL FILTER SIZES
CABINET
HEIGHT
OUTDOOR
FAN DIAMETER
FILTER SIZE
(IN. X IN.)
APPROXIMATE AIR FLOW
RANGE (CFM)
APPROXIMATE FILTER
AREA (SQ. IN.)*
30” 20 (2) 14”x25” 700 - 1300 700
24” (1) 12”x20” and (1) 16”x25” 640
34” 20 (2) 16”x25” 900 - 1400 800
24” (1) 12”x20” and (2) 10”x25” 740
38” 20” (2) 18”x25” 1100 - 1600 900
24” (1) 12”x20” and (2) 12”x25” 840
42” 20” (2) 20”x25” 1300 - 1800 1000
24” (1) 12”x20” and (2) 14”x25” 940
* Based on velocity of 300 ft/min for disposable filters.
Unconditioned Spaces
All duct work passing through unconditioned space must
be properly insulated to minimize duct losses and prevent
condensation. Use insulation with an outer vapor barrier. Refer
to local codes for insulation material requirements.
Acoustical Duct Work
Certain installations may require the use of acoustical lining
inside the supply duct work.
• Acoustical insulation must be in accordance with the current
revision of the Sheet Metal and Air Conditioning Contractors
National Association (SMACNA) application standard for
duct liners.
• Duct lining must be UL classified batts or blankets with a
fire hazard classification of FHC-25/50 or less.
• Fiber duct work may be used in place of internal duct liners if
the fiber duct work is in accordance with the current revision
of the SMACNA construction standard on fibrous glass
ducts. Fibrous duct work and internal acoustical lining must
be NFPA Class 1 air ducts when tested per UL Standard
181 for Class 1 ducts.

9
UNIT INSTALLATION
Packaging Removal
Remove the shipping carton and User’s Manual from the
equipment. For rooftop installations, remove and discard the
two supports attached beneath the unit.
Rigging & Hoisting
WARNING:
To avoid the risk of property damage, personal injury,
or death, it is the rigger’s responsibility to ensure
that whatever means are used to hoist the unit are
safe and adequate:
• The lifting equipment must be adequate for the
load. Refer to Table 5 (page 18) for unit weights.
• The unit must be lifted from the holes in the base
rails using cables or chains.
• Spreader bars are required to protect the unit and
ensure even loading.
• Keep the unit in an upright position at all times.
The rigging must be located outside the units
center of gravity. Refer to Figure 10 (page 18) for
locating the center of gravity.
• All panels must be securely in place during rigging
and hoisting.
Clearances to Combustible Materials
These units are certified as combination heating and cooling
equipment for outdoor rooftop or ground level installations.
Units may be installed on combustible flooring or Class A,
B, or C roofing material when used with bottom supply and
return air ducts as long as the following requirements are met:
• If using bottom discharge with return air ducts a roof curb
must be installed prior to unit installation. See Rigging and
Hoisting section for setting of the unit.
• Sufficient clearance for unobstructed airflow through the
outdoor coil must also be maintained in order to achieve
rated performance. See page 5for information about
locating the equipment.
Rooftop
Rooftop installations must be located according to local building
codes or ordinances and these requirements:
• The roof must be capable of handling the weight of the
unit. For unit weights, see Table 5. Reinforce the roof if
necessary.
• The appropriate accessory roof curb must be installed prior
to unit installation. The roof curb must be square and level
to ensure proper condensate drainage. Please follow all
instructions provided with the kit. See Figure 3 (page
10).
• Secure roof curb or frame to roof using acceptable
mechanical methods per local codes. NOTE: Make sure the
two supports beneath the unit have been removed.
Ground Level
Ground level installations must be located according to local
building codes or ordinances and these requirements:
• Clearances must be in accordance with those shown in
Figure 1 (page 5).
• A suitable mounting pad must be provided and be separate
from the building foundation. The pad must be level to ensure
proper condensate disposal and strong enough to support
the unit’s weight. The slab height must be a minimum of 2”
(5cm) above grade and with adequate drainage. See Figure
4 (page 10).
• Remove and discard the horizontal Supply and Return duct
covers located on the rear of the unit. Form duct attachment
flanges by bending the sheet metal outward 90 degrees
along the perforated lines.
• Firmly attach ductwork directly to these flanges with
screws or other approved mechanical connections and
not to the Supply/Return air panels to avoid damage to
internal components of the equipment. Once completed
use approved duct sealing methods to ensure an air and
watertight seal is achieved.
Horizontal to Downflow Conversion
The unit is shipped ready for horizontal duct connections.
If down flow ducts are required, the unit must be converted
following the steps below for both the supply and return ducts.
1. Remove the horizontal duct cap.
2. Locate the duct cap inside the duct openings and remove
the screw holding it in place.
3. Lift the cap out of the unit. (Hint: The cap can be pushed
up from the bottom by reaching through the fork slot).
4. Cover the horizontal duct opening with the horizontal duct
cap. The insulation will be on the indoor side.
5. Fasten the cover with screws to seal.
6. Remove and discard the two wood supports beneath the
unit.
Condensate Drain
Condensate is removed from the unit through the 3/4” female
pipe fitting located on the front side of the unit. See Figure 5
(page 10).
Install a 2 inch condensate trap in the drain line of the same
size and prime with water. When connecting rigid drain line,
hold the female fitting with a wrench to prevent twisting. Do
not over tighten! Refer to local codes and restrictions for
proper condensate disposal requirements.

10
ELECTRICAL WIRING
WARNING:
ELECTRICAL SHOCK, FIRE OR
EXPLOSION HAZARD
Failure to follow safety warnings exactly could
result in serious injury, death, or property damage.
Improper servicing could result in dangerous
operation, serious injury, death or property
damage.
• Before servicing, disconnect all electrical power
to furnace.
• When servicing controls, label all wires prior to
disconnecting. Reconnect wires correctly.
• Verify proper operation after servicing.
• Electrical connections must be in compliance with
all applicable local codes and ordinances, and with
the current revision of the National Electric Code
(ANSI/NFPA 70).
• For Canadian installations the electrical connections and
grounding shall comply with the current Canadian Electrical
Code (CSA C22.1 and/or local codes).
IMPORTANT NOTE:
If replacing any of the original wires supplied with the
furnace, the replacement wire must be copper wiring
having the same guage, voltage, and temperature rating.
Pre-Electrical Checklist
√Verify the voltage, frequency, and phase of the supply
source match the specifications on the unit rating plate.
√Verify that the service provided by the utility is sufficient to
handle the additional load imposed by this equipment. See
Table 2 (page 11) and Table 10 (page 25) (or the unit
rating label) for proper high voltage wiring requirements.
√Verify factory wiring is in accordance with the unit wiring
diagram. See Figure 12 (page 23) and Figure 13 (page
24). Make sure the connections didn’t loosen during shipping
or installation.
Grounding
WARNING:
The unit cabinet must have an uninterrupted or
unbroken electrical ground to minimize personal
injury if an electrical fault should occur. Do not use
gas piping as an electrical ground!
This unit must be electrically grounded in accordance with
local codes or, in the absence of local codes, with the National
Electrical Code (ANSI/NFPA 70) or the CSA C22.1 Electrical
Code. Grounding of the unit is accomplished by using the
grounding lug provided in the control box.
Line Voltage
• The line voltage to the unit should be supplied from a
dedicated branch circuit containing the correct fuse or circuit
breaker for the unit.
Figure 3. Roof Top Installation
Figure 4. Ground Level Installation
2”
Condensate Drain
Figure 5. Refrigerant Service Ports &
Condensate Drain Locations

11
• An electrical disconnect must be located within sight
of and readily accessible to the unit. This switch shall be
capable of electrically de-energizing the outdoor unit. See
unit data label for proper incoming field wiring. Any other
wiring methods must be acceptable to authority having
jurisdiction.
• Use only copper wire for the line voltage power supply to
this unit as shown in Table 2. Use proper code agency listed
conduit and a conduit connector for connecting the supply
wires to the unit. Use of rain tight conduit is recommended.
• Provide power supply for the unit in accordance with the
unit wiring diagram and the unit rating plate.
• Overcurrent protection must be provided at the branch circuit
distribution panel and sized as shown on the unit rating
label and according to applicable local codes. See Table
10 (or the unit rating plate) for minimum circuit ampacity
and maximum overcurrent protection limits.
• A wiring diagram is located on the inside cover of the control
access panel of the outdoor unit. The installer should become
familiar with the wiring diagram before making any electrical
connections to the outdoor unit. See Figure 12 and Figure
13.
• Units are shipped from the factory wired for 230 volt
transformer operation.
• Connect the line-voltage leads to the terminals on the
contactor inside the control compartment.
Thermostat / Low Voltage Connections
• This unit is designed to operate from a 24 VAC Class II
control circuit. A single stage cooling / single stage heating
thermostat should be used with this unit. A 2-stage cooling /
2-stage heating thermostat is recommended for economizer
operation. See Figure 6 (page 11) for typical thermostat
connection.
• The control circuit wiring must comply with the current
provisions of the NEC (ANSI/NFPA 70) and with applicable
local codes having jurisdiction. Thermostat connections
should be made in accordance with the instructions supplied
with the thermostat and the indoor equipment.
• The low voltage wires must be properly connected. Route
24V control wires through the sealing grommet near the
power entrance.
• Several thermostat options are available depending on the
accessories installed with the unit. Select a thermostat that
operates in conjunction with the installed accessories.
• The thermostat should be mounted about 5 feet above the
floor on an inside wall. DO NOT install the thermostat on
an outside wall or any other location where its operation
may be adversely affected by radiant heat from fireplaces,
sunlight, or lighting fixtures, and convective heat from warm
air registers or electrical appliances. Refer to the thermostat
manufacturer’s instruction sheet for detailed mounting
information.
Checking Heat Anticipator Settings
• Add the current draw of the system heating components.
OR
• Measure the current flow on the thermostat R-Wcircuit
after the circulating blower motor has started. Set the heat
anticipator according to the thermostat manufacturer’s
instructions for heat anticipator settings.
Blower Speed
The blower speed is preset at the factory for fan only, heating,
and cooling operation. These factory settings are listed in
Table 6 (page 19) and Table 7 (page 20). For optimum system
performance and comfort, it may be necessary to change the
factory set speed.
CAUTION:
To avoid personal injury or property damage, make
sure the motor leads do not come into contact with
any uninsulated metal components of the unit.
5-Speed ECM Motor
• Shut off all electrical power to the unit and remove the
control panel. NOTE: The furnace board has slide switches
to select between blower speeds that are preset from the
factory. The heat, cool, and fan speed can be changes by
sliding the switch from the available options of L-Low. ML-
Medium Low, MH-Medium High, H-High. The blower motor
speeds increase as the switch is moved from Low to High.
• A movable jumper beside the blower speed slide switches
change fan speed(G call). The fan speed is preset from
the factory for the Lowest blower speed L. Changing this
position of the jumper one setting at a time will increase the
fan speed.
Optional Furnace Control Board Connections
Electronic Air Cleaner
The furnace control board provides output terminals for an
optional electronic air cleaner (EAC) that can be installed in the
return air duct of your system. THE EAC output is energized
any time the HEAT or COOL blower speed is energized.
Control ratings are 1.0 Amp. @ 240 VAC. Output connections
are made via board terminals labeled EAC and NEUTRAL.
COPPER WIRE SIZE — AWG
(1% VOLTAGE DROP)
SUPPLY WIRE LENGTH-FEET SUPPLY CIRCUIT
AMPACITY
200 150 100 50
6 8 10 14 15
4 6 8 12 20
4 6 8 10 25
4 4 6 10 30
3 4 6 8 35
3 4 6 8 40
2 3 4 6 45
2 3 4 6 50
2 3 4 6 55
1 2 3 4 60
NOTE: Wire Size based on N.E.C. for 60° type copper conductors.
Table 2. Copper Wire Size Figure 6. Typical Thermostat Connection
(Field Supplied) for 1-Stage Cool / 1-Stage Heat
C
Y1
R
G
W1
R
C
Y
G
W1
Y2
TERMINAL BLOCK
FURNACE
BOARD
Optional, Refer to
Thermostat Instructions
INDOOR THERMOSTAT
SUB-BASE (TYPICAL) A1

12
Humidifier
The furnace control board provides output terminals for
an optional humidifier (HUM) that can be installed on your
system. The HUM output is energized any time the furnace
inducer motor is energized. Control ratings are 1.0 Amp. @
240 VAC. Output connections are made via board terminals
labeled HUM and NEUTRAL.
Check all factory wiring to the units wiring diagram. Inspect the
factory wiring connections to be sure none loosened during
shipping or installation.
GAS SUPPLY & PIPING
WARNING:
FIRE OR EXPLOSION HAZARD
• Failure to follow safety warnings exactly could result
in 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.
• All gas piping must be installed in compliance with
local codes and utility regulations. In the absence of
local codes the gas line installation must comply with
the latest edition of the National Fuel Gas Code ANSI
Z223.1 or CAN/CGA B149 Installation Codes.
• Some local codes require the installation of a manual
main shut-off valve and ground joint union external to the
unit. The shut-off valve should be readily accessible for
service and/or emergency use. Consult the local utility
or gas supplier for additional requirements regarding
placement of the manual main gas shut-off. See Figure
7 (page 13).
• The manifold pressure must be set to the appropriate
value for your installation. Refer to the Manifold
Pressure Adjustment section (page 14) for adjustment
instructions.
• Gas piping must never run in or through air ducts,
chimneys, gas vents, or elevator shafts.
• The main gas shutoff valve and main power disconnect
to the unit must be properly labeled by the installer in
case emergency shutdown is required.
• An 1/8 inch NPT plugged tap must be installed in
the gas line immediately upstream of the gas supply
connection to the unit for use when measuring the gas
supply pressure. The plug should be readily accessible
for service use.
• A drip leg should be installed in the vertical pipe run to
the unit. See Figure 7.
This unit only has right side gas entry. When connecting the
gas, provide clearance between the gas supply line and the
entry hole in the unit’s casing to avoid unwanted noise and/
or damage to the unit. A typical gas service hookup is shown
in Figure 7.
Table 8 (page 21) lists gas pipe capacities for standard pipe
sizes as a function of length in typical applications based on
nominal pressure drop in the line.
Leak Check
WARNING:
FIRE OR EXPLOSION HAZARD
Failure to follow safety warnings exactly could
result in serious injury, death, or property damage.
Never test for gas leaks with an open flame. Use
a commercially available soap solution made
specifically for the detection of leaks to check all
connections. A fire or explosion may result causing
property damage, personal injury or loss of life.
After the gas piping to the unit is complete, all connections
must be tested for gas leaks. This includes pipe connections
at the main gas valve, emergency shutoff valve and other
gas connectors. A soap and water solution can be applied on
each joint or union using a small paintbrush. If any bubbling
is observed, the connection is not sealed adequately and
must be retightened. Repeat the tightening and soap check
process until bubbling ceases.
• If pressure testing the gas supply lines at pressures
greater than 1/2 psig (14 inches WC), the unit must be
disconnected from the gas supply piping system to
prevent damage to the gas valve.
• If the test pressure is less than or equal to 1/2 psig
(14 inches WC), the unit must be isolated from the gas
supply line by closing the manual shut-off valve.
High Altitude Conversion - Natural Gas
For installations between zero and 5000 ft above sea level,
the factory installed gas orifice should be used. High altitude
conversion with this furnace depends on the installation
altitude and the heating value of the gas. Installation of this
furnace at altitudes above 2,000 feet shall be in accordance
with local codes, or in the absence of local codes, the National
Fuel Gas Code, ANSI Z223.1/NFPA 54. Please consult your
local code authority.
WARNING:
The reduction of input rating necessary for high
altitude installation may only be accomplished with
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.
The furnaces are shipped from the factory with orifices and
gas regulator settings for natural gas operation up to 5000
ft. At 2,000 feet, the NFGC requires that this appliance be
derated 4% for each 1,000 feet of altitude. For example, at
2,000 feet the input needs to be reduced 8%, at 3,000 feet
(12%), etc. This deration is in reference to the input rate and
gas heating value at sea level.

13
To derate the furnace requires knowing the heating value of
the gas at the installation site. Heating values at particular job
sites vary for two reasons:
1. The chemical mixture of the gas varies across regions and
is expressed as the “sea level heating value”.
2. The heating value varies by altitude. For this reason,
especially in high altitude areas, the local gas utility specifies
the heating value at the residence’s gas meter as the “local
value”.
WARNING:
This unit was equipped at the factory for use with
natural gas only. LP/Propane cannot be used with this
unit. Failure to follow safety warnings exactly could
result in serious injury, death or property damage.
START UP & ADJUSTMENTS
Pre-Start Check List
√Verify the unit is level and allows condensate to drain.
√Verify all clearance requirements are met and there is free
airflow to and from the outdoor coil.
√Verify that the duct work is sealed to prevent air leakage
and air filter is installed.
√Verify that the line voltage power leads are securely
connected and the unit is properly grounded.
√Verify that the low voltage wires are securely connected to
the correct terminals in the low voltage area of the control
box.
√Verify that the gas line service pressure does not exceed
10.0 inches WC (0.36 psig), and is not less than 4.5 inches
WC (0.16 psig) for natural gas.
√Verify that the burner limit control is closed. If necessary,
press the red button to reset the control. DO NOT install a
jumper wire across the control to defeat its function. If the
control reopens upon start-up, DO NOT reset the control
without identifying and correcting the fault condition which
caused the control to trip.
Ground
Joint
Union
Dripleg
Shut-Off Valve with 1/8 NPT plugged tap
NOTE: Some utilities require Shut-Off
Valve to be 4 to 5 feet above floor
Automatic Gas Valve
(with manual shut-off)
Figure 7. Typical Gas Hookup - Right Side Entry
√Verify that the gas line has been purged and all connections
are leak tight.
√Verify that all exterior panels are replaced and securely
fastened.
√Verify that the outdoor fan turns freely.
√Verify that the power supply branch circuit overcurrent
protection is sized properly.
√Verify that the thermostat is wired correctly. The thermostat
function switch should be set to OFF and the thermostat
fan switch should be set to AUTO.
Start-Up Procedure
WARNING:
If this unit is equipped with crankcase heaters, allow
24 hrs for heating of the refrigerant compressor
crankcase prior to start up or anytime the power
has been removed for more than 12 hrs. Failure to
comply may result in damage or cause premature
failure of the system.
Air Circulation
Leave the thermostat system mode on OFF, and set the fan
mode to ON. Blower should run continuously. Check the air
delivery at the supply registers and adjust register openings
for balanced air distribution. Examine ductwork for leaks or
obstruction if insufficient air is detected. Set the thermostat
fan mode to AUTO. The blower should stop running.
System Cooling
1. Set the thermostat’s system mode to COOL and the fan
mode to AUTO. Gradually lower the thermostat temperature
setpoint below room temperature and verify the compressor,
fan and indoor blower energize.
2. Feel the air being circulated by the indoor blower and verify
that it is cooler than ambient temperature. Listen for any
unusual noises. If unusual sounds occur, determine the
source of the noise and correct as necessary.
3. Allow the cooling system to operate for several minutes and
then set the temperature selector above room temperature.
Verify the fan and compressor cycle off with the thermostat.
NOTE: The blower will also stop after a 60 second delay.

14
System Heating
1. Set the thermostat to the lowest setting.
2. Follow the procedures given on the operating instruction
label, this manual or attached inside the louvered control
access panel.
3. Set the thermostat above room temperature and verify the
Operating Sequence. See page 16.
4. Verify that the compressor and outdoor fan motor are not
energized.
5. After the unit has run for approximately five minutes, set the
thermostat below room temperature and verify the shutdown
sequence; steps 10, 11, & 12 in the Operating Sequence
section on page 16.
Verifying & Adjusting Temperature Rise
Verify the temperature rise through the unit is within the range
specified on the unit data label. Temperature rises outside the
specified range could result in premature heat exchanger failure.
1. Place thermometers in the return and supply air stream as
close to the unit as possible. The thermometer on the supply
air side must be shielded against direct radiation from the
heat exchanger to avoid false readings.
2. Adjust all registers and duct dampers to the desired
position. Run the unit for 10 to 15 minutes before taking any
temperature readings. The temperature rise is the difference
between the supply and return air temperatures.
NOTE: For typical duct systems, the temperature rise will fall
within the range specified on the data label (with the blower
speed at the factory recommended setting) shown in Table 6
(page 19) or Table 7 (page 20). If the measured temperature
rise falls outside the specified range, it may be necessary
to change the blower speed. Lowering the blower speed
increases the temperature rise and a higher speed decreases
the temperature rise.
Verifying & Adjusting Firing Rate
CAUTION:
Do not re-drill the burner orifices. If the orifice size
must be changed, use only new orifices.
The firing rate must be verified for each installation to prevent
over-firing of the unit. The firing rate must not exceed the
rate shown on the unit data label. To determine the firing
rate, follow the steps below:
1. Obtain the gas heating value (HHV) from the gas supplier.
2. Shut off all other gas fired appliances.
3. Start the unit in heating mode and allow it to run for at least
3 minutes.
4. Measure the time (in seconds) required for the gas meter
to complete one revolution.
5. Convert the time per revolution to cubic feet of gas per hour
using Table 9 (page 21).
6. Multiply the gas flow rate in cubic feet per hour by the
heating value of the gas in Btu per cubic foot to obtain the
firing rate in Btu per hour. See Example.
Example:
• Time for 1 revolution of a gas meter with a 1 cubic foot
dial = 40 seconds.
• From Table 9, read 90 cubic feet gas per hour.
• Local heating value of the gas (obtained from gas supplier)
= 1,040 Btu per cubic foot.
• Input rate = 1,040 x 90 = 93,600 Btuh.
7. Adjust the manifold pressure if necessary. See Manifold
Pressure Adjustment below. For additional information about
elevations above 2,000 feet, see page 12.
Manifold Pressure Adjustment
The manifold pressure must be set to the appropriate value
for your installation. To adjust the manifold pressure:
1. Obtain the required manifold pressure setting
NOTE: The values listed in the tables are based on sea
level values. At higher altitudes, the heating value of gas
is lower than the sea level heating value.
2. Remove the regulator capscrew (Figure 8) from the INLET
side of the regulator.
3. Slowly turn the adjustment screw inside the regulator to
obtain the appropriate manifold pressure.
NOTE: Turning the screw clockwise increases the pressure
and turning the screw counter-clockwise decreases the
pressure. To prevent backing the screw all the way out from
the valve, turn the screw slowly.
4. Replace and tighten the regulator capscrew over the
adjustment screw.
Verifying Over-Temperature Limit Control Operation
1.Verify the louvered control access panel is in place and that
there is power to the unit.
2.Block the return airflow to the unit by installing a close-off
plate in place of or upstream of the filter.
3.Set the thermostat above room temperature and verify the
units operating sequence on page 16.
NOTE: The over-temperature limit control should turn off the gas
valve within approximately four minutes (exact time depends
on the efficiency of the close-off when blocking the return air).
The circulating air and combustion blowers should continue
to run when the over-temperature limit control switch opens.
4.Remove the close-off plate immediately after the over-
temperature limit control opens. If the unit operates for more
than four minutes with no return air, set the thermostat below
room temperature, shut off power to the unit, and replace
the over-temperature limit control.
Verifying Burner Operation
CAUTION:
The door over the burners may only be open for
inspection purposes only. The door must be installed
during unattended operation.
1. Remove the burner compartment door and note the location
of the sightglass on burner head.
2. Set the thermostat above room temperature and observe
the ignition sequence. NOTE: The burner flame should be
present by seeing a glow through the sightglass.
Capscrew
Inlet
Pressure
Ta p
Manifold
Pressure
Ta p
ON/OFF Switch
Figure 8. Regulator Capscrew & Tap Locations

15
3. After validating the flame, change the thermostat setting to
below room temperature.
4. Verify the burner flame is completely extinguished.
5. Replace the burner compartment door.
Verify Operation of the Supply Air Limit Switch
A properly functioning limit switch should turn off the gas
valve when the return is blocked (time depends on how well
the return air is blocked). The circulating air and combustion
blowers should continue to run when the limit switch opens.
1. Verify the blower door is securely mounted in place and
that there is power to the furnace.
2. Block the return airflow to the furnace by installing a close-
off plate in place of or upstream of the filter(s).
3. Set the thermostat above room temperature and observe
the Operating Sequence.
4. Remove the close-off immediately after the limit switch
opens. If the furnace continues to operate with no return
air, set the thermostat below room temperature, shut off
power to the furnace, and replace the limit switch.
OPERATING SEQUENCE
The operating sequences for the heating, cooling, and fan
modes are described below. Refer to the field and unit wiring
diagram. See Figure 12 (page 23) and Figure 13 (page 24).
Heating Cycle
1. The thermostat calls for heat by energizing the Wterminal
with 24VAC.
2. The control verifies the safety circuit pressure switch is open
and high temperature limit switch circuit is closed.
3. If the pressure switch is open, the control energizes the
inducer and waits for the pressure switch to close. The
pressure switch must close within 10 seconds.
4. The control runs the inducer for a 30 second pre-purge.
5. The control energizes the igniter output for a 30 second
warm-up period.
6. The control energizes the main gas valve for 3 seconds.
7. If the flame is proved after igniting the gas, the control de-
energizes the igniter. The gas valve and inducer remain
energized. The control goes to blower on delay.
8. If flame is present, the control energizes the blower on
the selected HEAT speed 30 seconds after the gas valve
opened. The gas valve remains energized while the inducer
ramps to Max. RPM over a programmed time period.
9. When the thermostat demand for heat is satisfied, the control
de-energizes the gas valve. The inducer output remains on
for a 90 second post-purge period.
10.Blower off timing of 60, 90, 120, & 180 seconds (depending
on the movable jumper setting) begins when the thermostat
is satisfied. See Figure 14 (page 16). The control will
operate at the selected HEAT speed of 60 seconds, then
change to FAN speed for the remaining off delay time. If
the blower off delay jumper is not present, the fan should
still operate for 120 seconds at the selected HEAT speed.
The indoor blower motor is de-energized after a blower off
delay as selected by the movable jumper.
ALTITUDE ABOVE
SEA LEVEL
HEATING VALUE BTU/CU. FT
ORIFICE
800 TO 899 900 TO 999 1,000 TO
1,100
ZERO TO 5,000
FT. 3.5 3.5 3.5 FACTORY
INSTALLED
Table 3. Manifold Pressure Setting (In WC)
for Natural Gas
Cooling Cycle
1. The thermostat calls for cooling by energizing the Y& G
terminal with 24VAC.
2. The control energizes the blower in the cooling speed and
sends 24VAC to the contactor in the condensing section.
3. When the thermostat removes the call for cooling, the
contactor in the outdoor condensing section is de-energized
and the control continues to run the fan for a period of 60
seconds.
Fan Mode
• When the thermostat energizes the Gterminal for continuous
fan (without calling for heat or cooling), the indoor fan is
energized on the selected FAN speed. See Figure 6 (Page
11). The control defaults to MEDIUM HIGH if the movable
jumper is not attached.
• If a call for cooling occurs during continuous fan, the blower
will switch over to the selected COOL speed.
• If the Wterminal receives a call for heat during continuous
fan, the blower will de-energize and reset to delayed ON
timing.
• A call for fan is ignored while in lockout.
EQUIPMENT MAINTENANCE
WARNING:
ELECTRICAL SHOCK, FIRE OR
EXPLOSION HAZARD
Failure to follow safety warnings exactly could
result in serious injury, death, or property damage.
Improper servicing could result in dangerous
operation, serious injury, death or property
damage.
• Before servicing, disconnect all electrical power
to furnace.
• When servicing controls, label all wires prior to
disconnecting. Reconnect wires correctly.
• Verify proper operation after servicing.
CAUTION:
Use care when removing parts from this unit.
Personal injury can result from sharp metal edges
present in all equipment of sheet metal construction.
Proper maintenance is important to achieve optimum
performance from the system. The ability to properly perform
maintenance on this equipment requires certain mechanical
skills and tools. If you do not possess these skills, contact your
dealer for maintenance. Consult your local dealer about the
availability of maintenance contracts. Routine maintenance
should include the following:
CAUTION:
The unit should never be operated without a filter
in the return air system. Replace disposable filters
with the same type and size.

16
• Inspect, clean or replace air filters at the beginning of each
heating and cooling season, or more frequently if required.
Refer to Table 1 (page 8) for recommended external
filter sizes
• Inspect the condensate drain and outdoor coil at the
beginning of each cooling season. Remove any debris.
Clean the outdoor coil and louvers as necessary using a
mild detergent and water. Rinse thoroughly with water.
• Inspect the electrical connections for tightness at the
beginning of each heating and cooling season.
• The blower compartment should be cleaned monthly during
the heating and cooling seasons to remove any dirt and lint
that may have accumulated in the compartment or on the
blower and motor. Buildup of dirt and lint on the blower and
motor can create excessive loads on the motor resulting in
higher than normal operating temperatures and possible
shortened service life.
• Maintain heat exchanger and burners. The unit should
operate for many years without excessive scale buildup in
the heat exchanger, however, the heat exchanger, the vent
system, and the burners should be inspected and cleaned
(if required) by a qualified Technician annually to ensure
continued safe operation. Particular attention must be given
to identify deterioration from corrosion or other sources.
• The motors for the circulating air blower, outdoor fan, and
combustion blower are pre-lubricated at the factory. No
further oiling is required for the life of this product.
• Inspect and clean the screen of the vent cover assembly
at the beginning of each heating and cooling season.
Heat Exchanger & Burner Maintenance - The furnace
should operate for many years without soot buildup in the
flue passageways, however, the flue and vent system should
be inspected and cleaned (if required) by a qualified service
technician annually to ensure continued safe operation. Pay
attention to any deterioration from corrosion or other sources.
Lubrication - The bearings in the blower motor and inducer
blower used in these furnaces are pre-lubricated and sealed by
the manufacturer. No further oiling of the bearings is required
for the life of the motor.
Cleaning of Flame Sensor - If the flame sensor is suspect
for Loss of Flame fault code, the sensor can be cleaned to
see if that remedies the issue. Follow steps 1 - 10. See Figure
14 (page 26) for component location.
CAUTION:
Due to igniter/flame sensor assembly location, a
new gasket should be on hand before servicing this
part. One new gasket is provided in the furnace extra
parts package. Failure to re-seal the assembly after
service can result in abnormal furnace operation.
1. Shut off gas supply to the furnace at the meter or at a manual
valve in the supply piping.
2. Turn off all power to the furnace and set the thermostat to
its lowest setting.
3. Remove the louvered door from the unit.
4. Turn the gas control switch to the OFF position.
5. Remove the 2 screws securing the combustion air orifice
plate to the air/fuel mixing tube (if needed to access the
ignitor/flame sensor assembly cover on smaller models).
6. Remove 8 screws from perimeter of access cover plate.
7. Lift the assembly and bracket straight up out of the burner box
and off the HX panel. NOTE: Use of a flat blade screwdriver
between assembly bracket and top of burner mounting
bracket to help leverage bracket off may be required. See
Figure 9.
8. Clean the flame sensor using steel wool being careful not
to damage the igniter.
9. Replace old gasket with new gasket ensuring correct
orientation, with adhesive side to the bracket.
10.Replace igniter/flame sense assembly in reverse order
they were removed.
Vent System - Check the vent pipe and/or chimney for
corrosion or debris. Any corroded section of vent pipe must be
replaced, and any obstruction or blockage must be removed
prior to operating the furnace.
WARNING:
Holes in the vent pipe or heat exchanger can cause
combustion products to enter the home. Replace the
vent pipe or heat exchanger if leaks are found. Failure
to prevent the circulation of combustion products
into the living space can create potentially hazardous
conditions including carbon monoxide poisoning
that could result in personal injury or death.
Figure 9. Ignitor Flame Sensor Bracket
Access Cover
Perimeter
Screws (x8)

17
TROUBLESHOOTING
If the unit does not operate in the cooling mode, check the
following:
• Is the thermostat operating properly?
• Is the blower compartment doors in place?
• Is the furnace disconnect closed?
• Has the circuit breaker tripped or did any of the control board
fuses burn open? NOTE: There are 2 fuses, one on the
control board (3-amp) and one in a fuse holder (1.5-amp)
to the right of the control board.
• Is the gas turned on?
• Are any manual reset switches open?
• Is the filter dirty or plugged?
• Is the flame sensor coated? (Remove and clean with steel
wool. New gasket is required) See Cleaning of Flame Sensor
sectionon page 16.
• Are all the LED’s on the furnace control board constantly
ON? If not, refer to Table 4 or the wiring diagram (Figure
12 (page 23) and Figure 13 (page 24)) to determine fault
condition.
IMPORTANT NOTE: The furnace will lock out after 5 failed
attempts for ignition and will try again every hour if the call
for heat remains.
• If the inducer blower is operating and items above have been
verified, check the limit switch circuit and reset if necessary.
See Figure 14 (page 26) for component location.
• If the furnace operates when the limit switch circuit is reset,
contact a qualified service technician to identify and repair
the problem.
• If the furnace still doesn’t operate, check the flame roll-out
switch and reset if necessary. See Figure 14 for component
location.
• If the furnace operates when the flame rollout switch is
reset, contact a qualified service technician to identify and
repair the problem.
Table 4. Diagnostic Codes
DIAGNOSTIC DESCRIPTION GREEN LED RED LED
Control Fault (No Power) Off Off
L1/Neutral Polarity Fault Flash Flash
1 Hour Lockout Alternating Flash
Normal Operation On On
Pressure Switch Closed Fault On Flash
Pressure Switch Open Fault Flash On
Open Limit Switch Fault Flash Off
DIAGNOSTIC DESCRIPTION YELLOW LED
Low Flame Sensor Signal Continuous Flash
Flame Present On

18
Top View
24 9/10
13 1/2
16
12
13 3/10
13 1/2
16
12
CG
A
47 1/2
3/4" NPT Female
Drain Connector
B
DOWNFLOW
SUPPLY DUCT
OPENING
DOWNFLOW
RETURN DUCT
OPENING
23 1/2
Side View
BLOWER
ACCESS
ELECTRIC
SUPPLY ENTRY
(1.25 DIA.)
LOW
VOLTAGE
ENTRY (.88 DIA.)
GAS SUPPLY
ENTRY (1.63 DIA.)
27.90
7.29
4.07
47.42
Back View
12.45
12.45
4.0
D
8.75
Horizontal
Supply Duct
Opening
Horizontal
Return Duct
Opening
4.0
1.75
9.75 24.75
16.0
Condensing
Coil
13.5
16.0
16.0
C
13.5
Figure 10. Unit Dimensions
MODEL
NUMBER
UNIT
WEIGHT
SHIPPING
WEIGHT
CENTER OF GRAVITY HEIGHT IN INCHES (C)
A B WITH BASE RAILS WITHOUT BASE RAILS
(V)R104GD-024K055U 390 406 26.5 26.5 35.0 31.3
(V)R104GD-030K070U 390 406 26.0 26.5 35.0 31.3
(V)R104GD-036K070U 390 406 26.5 26.5 35.0 31.3
(V)R104GD-042K100U 438 455 27 26.5 39.0 35.3
(V)R104GD-048K100U 459 476 27 26.5 43.0 39.3
(V)R104GD-X60K100U 490 507 27 27.5 47.0 43.3
Table 5. Center of Gravity & Unit Shipping Weights
FIGURES & TABLES

19
Airflow Data
Table 6. Nominal Heating Airflow Rates & Temperature Rises (° F)
MODEL
NUMBER
HEATING
RISE
RANGE
MOTOR
TAP
EXTERNAL STATIC PRESSURE DROP - INCHES WATER COLUMN
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
(ACFM) (°F)
RISE (ACFM) (°F) RISE (ACFM) (°F) RISE (ACFM) (°F) RISE (ACFM) (°F) RISE (ACFM) (°F) RISE (ACFM) (°F) RISE (ACFM) (°F) RISE
(V)R104GD-
024K055U 35-65
Tap T1** 996 41 898 46 800 52 750 55 726 57 632 65 552 75 470 88
Tap T2
Tap T3
Tap T4
Tap T5
(V)R104GD-
030K070U 35-65
Tap T1 1243 42 1158 45 1076 49 984 53 906 58 845 62 782 67 762 69
Tap T2** 1393 38 1310 40 1255 42 1172 45 1099 48 1021 51 955 55 899 58
Tap T3
Tap T4
Tap T5
(V)R104GD-
036K070U 35-65
Tap T1 1243 42 1158 45 1076 49 984 53 906 58 845 62 782 67 762 69
Tap T2** 1393 38 1310 40 1255 42 1172 45 1099 48 1021 51 955 55 899 58
Tap T3
Tap T4
Tap T5
(V)R104GD-
042K100U 35-65
Tap T1 1098 68 1020 74 954 79 886 85 814 92 765 98 691 109 620 121
Tap T2 1453 52 1384 54 1326 57 1267 59 1204 62 1137 66 1095 68 1031 73
Tap T3** 1663 45 1605 47 1541 49 1489 50 1425 53 1366 55 1321 57 1260 60
Tap T4
Tap T5
(V)R104GD-
048K100U 35-65
Tap T1 1153 65 1071 70 1002 75 930 81 855 88 803 93 726 103 651 115
Tap T2** 1684 45 1597 47 1529 49 1467 51 1397 54 1323 57 1245 60 1171 64
Tap T3
Tap T4
Tap T5
(V)R104GD-
X60K100U 35-65
Tap T1 1589 47 1498 50 1391 54 1271 59 1165 64 1063 71 995 75 899 83
Tap T2** 1803 42 1710 44 1621 46 1513 50 1416 53 1320 57 1241 60 1146 65
Tap T3
Tap T4
Tap T5
** Denotes factory set heating speed
Tap 1 is factory set fan speed
Data is ACFM

20
Table 7. Nominal Cooling Airflow Rates & Temperature Rises (° F)
MODEL
NUMBER
MOTOR
TAP
EXTERNAL STATIC PRESSURE DROP - INCHES WATER COLUMN
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
SCFM SCFM SCFM SCFM SCFM SCFM SCFM SCFM
(V)R104GD-
024K055U
Tap T1 810 730 650 610 590 514 449 382
Tap T2 970 895 819 747 680 611 554 488
Tap T3 1112 1050 987 903 837 776 707 641
Tap T4* 1160 1105 1053 991 908 840 797 720
Tap T5 1472 1411 1350 1295 1228 1164 1097 1051
(V)R104GD-
030K070U
Tap T1 1036 965 897 820 755 704 652 635
Tap T2 1161 1092 1046 977 916 851 796 749
Tap T3 1294 1231 1178 1127 1066 1005 936 887
Tap T4* 1333 1268 1213 1161 1098 1035 964 913
Tap T5 1920 1872 1836 1785 1728 1699 1645 1592
(V)R104GD-
036K070U
Tap T1 1036 965 897 820 755 704 652 635
Tap T2 1161 1092 1046 977 916 851 796 749
Tap T3 1333 1268 1213 1161 1098 1035 964 913
Tap T4* 1439 1392 1340 1295 1250 1200 1145 1090
Tap T5 1920 1872 1836 1785 1728 1699 1645 1592
(V)R104GD-
042K100U
Tap T1 1098 1020 954 886 814 765 691 620
Tap T2 1450 1380 1326 1267 1204 1137 1095 1031
Tap T3* 1527 1469 1418 1357 1289 1243 1190 1132
Tap T4 1950 1884 1842 1790 1743 1687 1637 1571
Tap T5 2031 1992 1921 1871 1820 1770 1711 1650
(V)R104GD-
048K100U
Tap T1 1098 1020 954 886 814 765 691 620
Tap T2 1604 1521 1456 1397 1330 1260 1186 1115
Tap T3 1663 1605 1541 1489 1425 1366 1231 1260
Tap T4* 1871 1806 1747 1693 1631 1575 1509 1449
Tap T5 2031 1992 1921 1871 1820 1770 1711 1650
(V)R104GD-
X60K100U
Tap T1 1292 1218 1131 1033 947 864 809 731
Tap T2 1466 1390 1318 1230 1151 1073 1009 932
Tap T3 1774 1719 1661 1599 1529 1448 1384 1306
Tap T4* 2024 1973 1919 1857 1798 1731 1668 1600
Tap T5 2144 2087 2028 1962 1911 1849 1785 1718
* Denotes factory set cooling speed
Tap 1 is factory set fan speed
Data is with a dry coil