Lennox 15GCSX User Manual 2

INSTALLATION

E 2010 Lennox Industries Inc.

Dallas, Texas, USA

RETAIN THESE INSTRUCTIONS

FOR FUTURE REFERENCE

WARNING

Improper installation, adjustment, alteration, service or
maintenance can cause personal injury, loss of life, or
damage to property.

Installation and service must be performed by a
licensed professional installer (or equivalent),
service agency or the gas supplier.

INSTRUCTIONS

15GCSX SERIES UNITS

GAS PACKAGED UNITS (2−5 TONS)

506701−01
(38152A086)
06/11
Supersedes 03/11

Table of Contents

Unit Dimensions 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Parts Arrangement 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Shipping & Packing List 3. . . . . . . . . . . . . . . . . . . . . . . . .

General 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Safety Information 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Location Selection 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Rigging & Setting Unit 5. . . . . . . . . . . . . . . . . . . . . . . . . .

Clearances 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Installing Vent Hood 6. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Existing Common Vent Systems 6. . . . . . . . . . . . . . . . . .

Condensate Drain 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Filters 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Supply & Return Connections 7. . . . . . . . . . . . . . . . . . . .

Compressors 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Gas Supply and Piping 8. . . . . . . . . . . . . . . . . . . . . . . . . .

Electrical 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Blower Control 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cooling Start−Up 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Heating Start−Up 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unit Controls 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Condenser Fan Clearances 19. . . . . . . . . . . . . . . . . . . . .

Maintenance 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Planned Service 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Repair Parts & Accessories 22. . . . . . . . . . . . . . . . . . . . .

Litho U.S.A.

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.

Installation and service must be
performed by a qualified installer,
service agency or the gas supplier.

06/11

*2P0611*

WARNING

FIRE OR EXPLOSION HAZARD.

WHAT TO DO IF YOU SMELL GAS:

D Do not try to light any appliance.
D Do not touch any electrical switch; do not

use any phone in your building.

D Leave the building immediately.
D Immediately call your gas supplier from a

neighbor’s phone. Follow the gas supplier’s
instructions.

D If you cannot reach your gas supplier, call

the fire department.

506701−01

*P506701-01*

15GCSX Unit Dimensions − inches (mm)

FG

B

E

D

2−1/2 (64)

DOWNFLOW

SUPPLY AIR

OPENING

FF

AA

2−3/4

(70)

2−1/2 (64)

D

E

DOWNFLOW
RETURN AIR

OPENING

EE

TOP VIEW

BB

CCDD

Model

Number

15GCSXAV−24 74 94 125 97 15.5 28.5

C

15GCSXAV−30 74 94 125 97 15.5 28.5

15GCSXAV−36 84 101 126 105 16 29.5

15GCSXAV−42 108 136 176 140 20 33

15GCSX(A,B)V−48 112 137 177 144 20 33.5

15GCSX(A,B)V−60 117 143 184 151 20 33.5

Corner Weights

AA BB CC DD EE FF

lbs. lbs. lbs. lbs. in. in.

Center Of

Gravity

GAS PIPING INLET

2−1/2 (64)

Model No.

15GCSXAV−24
15GCSXAV−30
15GCSXAV−36

15GCSXAV−42
15GCSX(A,B)V−48
15GCSX(A,B)V−60

D

2 (51)

D

2−3/4

JK

E

E

(70)

HORIZONTAL

RETURN

AIR

OPENINGS (2)

H

FRONT VIEW

4−1/4 (108)

3−1/4 (83)

ELECTRICAL INLET

HORIZONTAL

SUPPLY AIR

A

OPENING

E

D

2−3/4

(70)

BACK VIEW

FLUE

OUTLET

L

CONDENSATE DRAIN

END VIEW

A B C D E F

in. mm in. mm in. mm in. mm in. mm in. mm

34−1/4 870 65−3/8 1661 36−1/2 927 11−1/4 286 17−1/4 438 20 508

38−1/4 972 75 1905 46 1168 11−1/4 286 19−1/4 489 22 559

END VIEW

Model No.

15GCSXAV−24
15GCSXAV−30
15GCSXAV−36

15GCSXAV−42
15GCSX(A,B)V−48
15GCSX(A,B)V−60

F G H J K L

in. mm in. mm in. mm in. mm in. mm in. mm

20 508 8−1/2 216 3 76 20−1/4 514 4−1/2 114 19 483

22 559 9−1/4 241 3−1/4 83 22−1/4 572 4 102 16−1/4 413

Page 2

Parts Arrangement

Air Purification System

PureAir

(Optional)

Evaporator

Coil

®

Gas Valve

Ignition Control

Shipping & Packing List

1 − Assembled gas package unit
1 − Vent hood assembly with screen and screws
As soon as the unit is received, it should be inspected for

possible damage during transit. If you find any damage,
immediately contact the last carrier.

Board

tested. The units require electric power, gas piping,
condensate drain and duct connections at the point of
installation. In addition, the heating vent hood must be
installed before the unit is placed into operation

Condenser

Coil

Control Box

Safety Information

General

These installation instructions are intended as a general
guide only, for use by an experienced, qualified contractor.

The 15GCSX units are single−package air conditioners
with two−stage gas heat designed for outdoor installation
on a rooftop or a slab.

The unit must be sized based on heat loss and heat gain
calculations made according to the methods of the Air
Conditioning Contractors of America (ACCA).

The units are shipped assembled. All piping, refrigerant
charge, and electrical wiring are factory−installed and

CAUTION

As with any mechanical equipment, personal injury
can result from contact with sharp sheet metal
edges. Be careful when you handle this equipment.

IMPORTANT

This unit is charged with HFC−410A refrigerant. Op­erating pressures for units charged with HFC−410A
are higher than pressures in units charged with
HCFC−22. All service equipment MUST be rated for
use with HFC−410A refrigerant.

Page 3

WARNING

Product contains fiberglass wool.

Disturbing the insulation in this product during
installation, maintenance, or repair will expose you
to fiberglass wool dust. Breathing this may cause
lung cancer. (Fiberglass wool is known to the State
of California to cause cancer.)

Fiberglass wool may also cause respiratory, skin,
and eye irritation.

To reduce exposure to this substance or for further
information, consult material safety data sheets
available from address shown below, or contact your
supervisor.

Lennox Industries Inc.

P.O. Box 799900
Dallas, TX 75379−9900

These units must be installed in accordance with all
applicable national and local safety codes.

These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
having jurisdiction before installation.

If components are to be added to a unit to meet local codes,
they are to be installed at the dealer’s and/or customer’s
expense.

These units are design listed by UL in both the United
States and Canada as follows:

D For use as a forced air furnace with cooling.

D For outdoor installation only.

D For installation on combustible material.

D For use with natural gas or L.P./propane gas only. Use of

L.P./propane gas requires installation of an L.P.
conversion kit, which must be ordered separately.

These units are not suitable for use with conventional
venting systems.

The following safety requirements must also be met when
the 15GCSX units are installed:

1 − Use only with the type of fuel approved for use with this

appliance. Refer to the unit rating plate.

2 − Position, locate and install the 15GCSX unit only as

outlined in these instructions.

3 − Provide adequate clearance around the vent hood as

specified in these instructions.

4 − Do not use an open flame to check for gas leaks. Use a

commercially available soap solution, which has been
designed specifically to check for gas leaks. Refer to
the Gas Supply and Piping section.

5 − Check the unit operation after start−up to make sure

that the 15GCSX is operating within the intended
temperature rise range. The duct system must be
designed to provide an external static pressure within
the allowable range. Refer to the unit rating plate.

Lennox does not recommend the use of 15GCSX units as a
construction heater during any phase of construction. Very
low return air temperatures, harmful vapors and operation
of the unit with clogged or misplaced filters will damage the
unit.

15GCSX units may be used for heating of buildings or
structures under construction, if the following conditions
are met:

D The vent hood must be installed per these installation

instructions.

D A room thermostat must control the furnace. The use of

fixed jumpers that will provide continuous heating is not
allowed.

D The return air duct must be provided and sealed to the

furnace.

D Return air temperature range between 60°F (16°C) and

80°F (27°C) must be maintained.

D Air filters must be installed in the system and must be

maintained during construction.

D Air filters must be replaced upon construction

completion.

D The input rate and temperature rise must be set per the

unit rating plate.

D One hundred percent (100%) outdoor air must be

provided for combustion air requirements during
construction. Installation of this unit in its intended
outdoor location will accomplish this.

D The heat exchanger, components, duct system, air

filters and evaporator coil must be thoroughly cleaned
following final construction clean−up.

D The unit operating conditions (including ignition, input

rate, temperature rise and venting) must be verified
according to these installation instructions.

NOTE − The Commonwealth of Massachusetts
stipulates these additional requirements:

D Gas furnaces shall be installed by a licensed

plumber or gas fitter only.

D The gas cock must be T handle" type.
D When flexible connectors are used, the maximum

length shall not exceed 36".

Location Selection

Use the following guidelines to select a suitable location for
these units.

1 − Unit is designed for outdoor installation only. Unit must

be installed so all electrical components are protected

from water.
2 − Condenser coils must have an unlimited supply of air.
3 − For ground level installation, use a level pre−fabricated

pad or use a level concrete slab with a minimum

thickness of 4 inches. The length and width should be

at least 6 inches greater than the unit base. Do not tie

the slab to the building foundation.
4 − Maintain level within a tolerance of 1/4 inch maximum

across the entire length or width of the unit.

Page 4

5 − Do not locate the unit where the combustion air supply

will be exposed to any corrosive substance, including
the following:
Permanent wave solutions,
Chlorinated waxes or cleaners,
Chlorine−based swimming pool chemicals,
Water−softening chemicals,
De−icing salts or chemicals,
Carbon tetrachloride,
Halogen−type refrigerants,
Cleaning solvents (e.g., perchloroethylene),
Printing inks, paint removers, varnishes, etc.,
Cements and glues,
Anti−static fabric softeners used in clothes dryers,
Masonry acid−washing materials,
Chlorinated laundry products,
Hydrochloric acid.

Rigging & Setting Unit

Exercise care when moving the unit. Do not remove any
packaging until the unit is near the place of installation. An
optional lifting lug kit (92M51) may be purchased
separately for use in rigging the unit for lifting. The

spreader lengths must exceed the width across the top
of the unit. Recommended spreader lengths: for use with

2, 2−1/2 and 3−ton units −− 44"; for use with 3−1/2, 4 and 5−ton
units −− 54".

CAUTION

Before lifting a unit, make sure that the weight is dis­tributed equally on the cables so that it will lift evenly.

Accessory Lift Kit

Lifting Bracket

Sheet Metal
Screw

Figure 1

Units may also be moved or lifted with a forklift while still in
the factory supplied packaging.

NOTE − Length of forks must be a minimum of 42 inches.

Clearances

All units require certain clearances for proper operation
and service. Refer to figure 2 for the clearances required
for combustible construction, servicing, and proper unit
operation.

NOTE − Do not permit overhanging structures or shrubs to
obstruct condenser air discharge outlet or vent outlet.

Service Clearances − Inches (Millimeters)

3 (76)

30

(762)

48 (1219)

NOTE − Top Clearance − 36 in. (914 mm)
NOTE − Entire perimeter of unit base requires
support when elevated above mounting surface.

Figure 2

In the U.S. units may be installed on combustible flooring
made from wood or class A, B, or C roof covering material.
In Canada, units may be installed on combustible flooring.

The products of combustion are discharged through a
screened vent outlet in the front mullion.

Install the unit so that the products of combustion will not
damage the outer building structure.

The vent outlet must be at least 4 feet below, 4 feet
horizontally from and 1 foot above any door, window or
gravity air inlet into the building. In addition, install the unit
so that the vent outlet is at least 3 feet above any forced air
inlet located within 10 feet.

Clearances to the vent outlet must also be consistent with
the requirements of the current National Fuel Gas Code
(Z223.1) and/or the standards of the current CSA B149
codes.

Figure 3 shows the minimum clearances to combustibles
required above and below the vent hood. The minimum
clearance in front of the vent hood is 24 inches.

Install the unit so that snow accumulation will not restrict
the flow of the flue products. Allow a required minimum
horizontal clearance of 4 feet from electric meters, gas
meters, regulators and relief equipment. In addition to the
above requirements, ensure that unwanted ice caused by
condensate is not allowed to accumulate around the unit.
Do not locate the unit on the side of the building where the
prevailing winter winds could trap moisture, causing it to

24

(610)

Page 5

freeze on the walls or on overhangs (under eaves). The
vent outlet should not discharge flue products on a
sidewalk, patio or other walkway where the condensate
could cause the surface to become slippery.

Do not install the unit so that the products of
combustion will be allowed to accumulate within a
confined space and recirculate.

Minimum Clearances to Combustible Materials

Above and Below Vent Hood

Minimum Clearance
AboveVent Hood:
Distance fromTop
ofVent Hood
toTop of Unit

Minimum Clearance
BelowVent Hood:
Distance from Bottom
ofVent Hood to Base
of Unit

Figure 3

Vent Hood Installation

The vent hood, screen and screws are shipped inside the
unit in the plastic bag which contains the installation
instructions.

1 − Insert the vent screen into the vent tube Once

inserted, the screen should be flush with the end of the
tube as shown in figure 4.

Vent Hood Installation

FrontView

Screen

VentTube

Screen is pre−formed

Figure 4

TopView

Screen

Vent Hood

Slotted side of
vent hood faces
condenser coil.

VentTube

NOTE −
Screws

should pass

through
sides of

screen to

hold screen

in place.

2 − Position the vent hood over the vent tube so that the

slotted side of the hood faces the condenser coil. Use

the four sheet metal screws (provided) to secure the

vent hood to the vent tube. The screws should pass

through the sides of the screen in order to hold the

screen in place.

The vent hood must be installed prior to unit start−up.

Existing Common Vent Systems

If this packaged outdoor unit is replacing an existing
indoor furnace that is being removed from a venting
system commonly run with a water heater or other gas
appliance, the venting system is likely to be too large to
properly vent the remaining attached appliance(s).

Conduct the following test while the water heater is
operating and the other gas appliances (which are not
operating) remain connected to the common venting
system.

1 − Seal any unused openings in the common venting

system.

2 − Inspect the venting system for proper size and horizontal

pitch. Determine that there is no blockage, restriction,
leakage, corrosion, or other deficiencies which could
cause an unsafe condition.

3 − Close all building doors and windows and all doors

between the space in which the appliances remaining
connected to the common venting system are located
and other spaces of the building. Turn on clothes
dryers and any appliances not connected to the
common venting system. Turn on any exhaust fans,
such as range hoods and bathroom exhausts, so they
will operate at maximum speed. Do not operate a
summer exhaust fan. Close fireplace dampers.

4 − Follow the lighting instructions. Turn on the appliance

that is being inspected. Adjust the thermostat so that
the appliance operates continuously.

5 − After the burner has operated for 5 minutes, test for

leaks of flue gases at the draft hood relief opening. Use
the flame of a match or candle, or smoke from a
cigarette, cigar, or pipe.

6 − After determining that each appliance connected to the

common venting system is venting properly, (step 3)
return all doors, windows, exhaust fans, fireplace
dampers, and any other gas−burning appliances to
their previous mode of operation.

7 − If a venting problem is found during any of the

preceding tests, the common venting system must be
modified to correct the problem.

If necessary, you must resize the common venting
system to the minimum vent pipe size determined by
using the appropriate tables in Appendix G. (These are
in the current standards of the National Fuel Gas Code
ANSI-Z223.1/NFPA 54 in the USA, and the

Page 6

appropriate Category 1 Natural Gas and Propane
appliances venting sizing tables in the current
standards of the CSA B149 Natural Gas and Propane
Installation Codes in Canada.)

Page 7

Condensate Drain

The 15GCSX unit is equipped with a 3/4 inch FPT coupling
for condensate line connection. Plumbing must conform to
local codes. Use a sealing compound on male pipe
threads.
The drain line must be properly trapped and routed to a
suitable drain. See figure 5 for proper drain arrangement.
The drain line must pitch to an open drain or pump a
minimum of 1 inch per 10 feet to prevent clogging of the
line. The drain line must be supported so that weight of
drain line is not carried by drain line connection. Seal
around drain connection with suitable material to prevent
air leakage into return air system.
Drain piping should not be smaller than drain connection
at coil. An open vent in drain line will some times be
required due to line length, friction and static pressure.
Drains should be constructed in a manner to facilitate
future cleaning.

NOTE − The condensate drain line MUST be trapped to
provide proper drainage.

CAUTION

Condensate line connection must be hand−tight­ened. Do not use tools.

Filters must always be installed ahead of evaporator coil
and must be kept clean or replaced. Dirty filters will reduce
the airflow of the unit. Filter sizes are shown in table 1.

Typical Condensate Drain

Minimum Pitch

1 in. (25 mm) per

10’ (3 m) of line

OPEN

VENT

Trap must be deep enough to offset maximum

static difference (Generally, 3 inches minimum).

UNIT

MOUNTING

FRAME

Figure 5

Filters

Filters are not factory−supplied with the unit; however,
optional internally installed filter kits are available. Filter kit
92M54 is used with 2, 2−1/2 and 3−ton units. Filter kit 92M55
is used with 3−1/2, 4 and 5−ton units. The filter kits
accommodate the use of 1", 2" or 4" filters. If the optional
filter kit is not used, a filter must be field−installed.

Page 8