Nortek GMH24-36MSK4DH1 User manual

Owner's Manual
Installation Instructions
Heat Pump
Air Handlers
Models:
GMH24-36MSK4DH1
GMH48-60MSK4DH1
Please read this owner’s manual carefully before operation and retain for future
reference. Specifications & illustrations subject to change without notice or incurring
obligations. If you have lost the owner’s manual, please visit www.NortekHVAC.com
for electronic version.

To Users
Thank you for selecting our product. Please read this instruction manual carefully
before installing and using the product, so as to master and correctly use the product. In
order to guide you to correctly install and use our product and achieve expected
operating effect, we hereby instruct as below:
(1) This appliance can be used by children aged from 8 years and above and persons
with reduced physical, sensory or mental capabilities or lack of experience and
knowledge if they have been given supervision or instruction concerning use of
the appliance in a safe way and understand the hazards involved. Children shall
not play with the appliance. Cleaning and user maintenance shall not be made by
children without supervision.
(2) In order to ensure reliability of product, the product may consume some power
under stand-by status for maintaining normal communication of system and
preheating refrigerant and lubricant. If the product is not to be used for long, cut off
the power supply; please energize and preheat the unit in advance before reusing
it.
(3) Please properly select the model according to actual using environment;
otherwise it may impact the using convenience.
(4) This product can’t be installed at corrosive, inflammable or explosive environment
or the place with special requirements, such as kitchen. Otherwise, it will affect the
normal operation or shorten the service life of the unit, or even cause fire hazard or
serious injury. As for above special places, please adopt special air conditioner
with anti-corrosive or anti-explosion function.
(5) If the product needs to be installed, moved or maintained, please contact our
designated dealer or local service center for professional support. Users should
not disassemble or maintain the unit by themselves, otherwise it may cause
relative damage, and our company will bear no responsibilities.
(6) All the illustrations and information in the instruction manual are only for reference.
In order to make the product better, we will continuously conduct improvement and
innovation. If there is adjustment in the product, please subject to actual product.
(7) If the supply cord is damaged, it must be replaced by the manufacturer, its service
agent or similarly qualified persons in order to avoid a hazard.

(8) Nortek Global HVAC, LLC assumes no responsibility for personal injury, property
loss or equipment damage caused by improper installation and commissioning,
unnecessary maintenance, or not following relevant national rules and regulations,
industrial standards and requirements in this instruction manual.
Exception Clauses
Manufacturer will bear no responsibilities when personal injury or property loss is
caused by the following reasons:
(1) Damage the product due to improper use or misuse of the product.
(2) Alter, change, maintain or use the product with other equipment without abiding by
the instruction manual of manufacturer.
(3) After verification, the defect of product is directly caused by corrosive gas.
(4) After verification, defects are due to improper operation during transportation of
product.
(5) Operate, repair, maintain the unit without abiding by instruction manual or related
regulations.
(6) After verification, the problem or dispute is caused by the quality specification or
performance of parts and components that produced by other manufacturers.
(7) The damage is caused by natural calamities, bad using environment or force
majeure.

Contents
1 Safety Precautions ............................................................ 1
2 Product Introduction ......................................................... 3
2.1 Product Description................................................................3
2.2 Optional Accessories..............................................................3
2.3 Physical Dimension................................................................4
2.4 Names of Main Parts..............................................................5
2.5 General Information ...............................................................5
2.6 Dip switch configuration .........................................................5
2.7 Fan Performance Data ........................................................6
3 Preparative for Installation................................................ 9
3.1 Pre-Installation Instruction......................................................9
3.2 Important Safety Instructions..................................................9
4 Installation........................................................................ 11
4.1 Unit Inspection .....................................................................11
4.2 Location ...............................................................................12
4.3 Piping Work..........................................................................13
4.4 Condensate Removal...........................................................15
4.5 Ductwork..............................................................................16
4.6 Electric Heater .....................................................................16
4.7 Electrical Installation ............................................................19
5 Installation Check and Trial Run .................................... 24
5.1 Checking Items after Installation ..........................................24
5.2 Trial Run ..............................................................................24
6 Common Malfunction and Elimination .......................... 25
7 Maintenance and Care..................................................... 27
7.1 Drain Pipe ............................................................................27

7.2 Notice before Seasonal Use.................................................27
7.3 Maintenance after Seasonal Use .........................................27
7.4 Parts Replacement...............................................................28
8 After-Sales Service .......................................................... 28
This marking indicates that this product should not be disposed with other household
wastes throughout the EU. To prevent possible harm to the environment or
human health from uncontrolled waste disposal, recycle it responsibly to
promote the sustainable reuse of material resources. To return your used
device, please use the return and collection systems or contact the retailer
where the product was purchased. They can take this product for
environmental safe recycling.

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1 Safety Precautions
This product can’t be installed at corrosive, inflammable or explosive environment
or the place with special requirements, such as kitchen. Otherwise, it will affect the
normal operation or shorten the service life of the unit, or even cause fire hazard or
serious injury. As for above special places, please adopt special air conditioner with
anti-corrosive or anti-explosion function.
Improper installation, adjustment, alteration, service, maintenance, or use can
cause explosion, fire, electrical shock, or other conditions which may cause death,
personal injury, or property damage. Consult a qualified installer, service agency, or
your distributor or branch for information or assistance. The qualified installer or agency
must use factory--authorized kits or accessories when modifying this product. Refer to
the individual instructions packaged with the kits or accessories when installing. Follow
all safety codes. Wear safety glasses, protective clothing, and work gloves. Use
quenching cloth for brazing operations. Have fire extinguisher available. Read these
instructions thoroughly and follow all warnings or cautions included in literature and
attached to the unit. Consult local building codes and National Electrical Code (NEC)
for special requirements. Recognize safety information. This is the safety--alert
symbol .
When you see this symbol on the unit and in instructions or manuals, be alert to the
potential for personal injury. Understand these signal words: DANGER, WARNING,
CAUTION and NOTICE. These words are used with the safety--alert symbol.
Indicates a hazardous situation that, if not avoided, will result in
death or serious injury.
Indicates a hazardous situation that, if not avoided, could result
in death or serious injury.
Indicates a hazardous situation that, if not avoided, may result
in minor or moderate injury.
Indicates important but not hazard-related information, used to
indicate risk of property damage.

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Electrical shock hazard:
Failure to follow this warning could result in personal injury or death.
Before installing, modifying, or servicing system, main electrical disconnect switch
must be in the OFF position. There may be more than 1 disconnect switch. Lock out
and tag switch with a suitable warning label.
PROPOSITION 65:
Respirable particles of fiberglass are known to State of California to cause cancer.
This appliance contains fiberglass insulation.
California Proposition 65 warnings are required for certain products, which are not
covered by the OSHA standards. All manufacturer products meet current federal OSHA
Guidelines for safety.
Products that contain or produce any of the more than 600 listed chemicals known
in California can cause cancer or birth defects, such as fiberglass insulation, lead in
brass and natural gas combustion products. Warnings are issued for such products
sold in California as required by California Proposition 65.
All “new equipment” shipped for sale in California will have labels stating that the
product contains and /or produces Proposition 65 chemicals. We cannot always know
“when, or if” products will be sold in the California market. Although we have not
changed our processes, having the same label on all our products facilitates
manufacturing and shipping.
All phases ofthis installation must conform toNATIONAL, STATE AND LOCAL
CODES. If it is required for additional information,please contact your local distributor.
The unit must be permanently grounded. Failure to do so can lead to electrical
shock causing personal injury or death.
The material of plenum and ductwork must meet the standard NFPA 90B.
The supply air plenum or duct must have a solid sheet metal bottom piece directly
after the air handler unit with no openings, registers or flexible air ducts located in it.
The first 6 inches of supply air plenum and ductwork must be constructed of sheet

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metal as required by NFPA 90B. Metal plenum of duct may be connected to the
non-combustible floor base for downflow. Exposing combustible non-metal. material to
the supply opening of a downflow unit can cause a fire resulting in property damage,
personal injury or death. If flexible supply air ducts are used they may be located only in
the side walls of the rectangular plenum, a minimum of 6 inches from the solid bottom.
2 Product Introduction
2.1 Product Description
The NORTEK air handler offer the perfect combination of superior product
quality, operating efficiency, operating sound levels and value for money. The
condensing unit uses the environmentally friendly refrigerant R410A, which is
chlorine-free to help prevent damage to the ozone layer.
2.2 Optional Accessories
Indoor unit accessories
No.
Name
Appearance
Q'ty
Usage
1 Throw-over
pipe
1
Connect the unit
with the liquid
pipe
2 Throw-over
pipe
1
Connect the unit
with the gas
pipe

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2.3 Physical Dimension
Unit: inch(mm)
Model
Dimension
W
D
H
A
B
GMH24-36MSK4DH1
21-1/4(540) 21-1/4(540) 48-1/4(1224) 11-5/8(295) 20(508)
24-3/4(630) 21-1/4(540) 57(1448) 11-5/8(295) 20(508)
GMH48-60MSK4DH1

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2.4 Names of Main Parts
2.5 General Information
Model
Cooling capacity(ton)
Optional electric heater (kW)
GMH24-36MSK4DH1(24K)
2.0
5/8/10
GMH24-36MSK4DH1(36K)
3.0
5/8/10
GMH48-60MSK4DH1(48K)
4.0
10/15/20
GMH48-60MSK4DH1(60K)
5.0
10/15/20
Model Motor @ 230V ~, 60Hz
HP
FLA
1/2 2.1
1 3.2
Unit: mm
Model
Filter size
490×516×15
525×516×15
GMH24-36MSK4DH1
GMH48-60MSK4DH1
GMH24-36MSK4DH1
GMH48-60MSK4DH1

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NOTES:
①.Based upon W/nominal tonnage, dry coil and filter should be installed.
②.Use 0.96 as approximate SCFM correction factor for wet coil.
2.6 Dip switch configuration
Set the indoor fan speed through the eight dip switches of the indoor main control
board. The higher level, the higher speed of the indoor unit fan. Operation Instruction is
below:
Dip switch settings must be completed before power on the unit.
After the unit is shut down or stopped at the temperature point, the indoor unit will
delay for a few minutes and then shut down. The refrigeration can realize the drying
function, relieve the mold of the air duct, and the heating can blow the waste heat and
relieve the heat accumulation in the air duct.
During installation and debugging, pay attention to check whether the temperature
controller has set the fan delay and shutdown time. If the temperature controller has
been set, the actual delay and shutdown time of the fan is equal to the temperature
controller setting time plus the fan delay time of the indoor unit.
Model
Level
Heat (SA2)
Cool (SA1)
GMH24-36MSK4DH1(24K)
Level 1
1
0
0
0
0
0
0
0
Level 2
1
0
0
1
0
0
0
0
Level 3
1
0
1
0
0
0
0
0
Level 4-Default
1
0
1
1
0
0
0
0
Level 5
1
1
0
0
0
0
0
0
Level 6
1
1
0
1
0
0
0
0
Level 7 1 1 1 0 0 0 0 0
Level 8
1
1
1
1
0
0
0
0
GMH24-36MSK4DH1(36K)
Level 1
0
0
0
0
0
0
0
0
Level 2
0
0
0
1
0
0
0
0
Level 3
0
0
1
0
0
0
0
0
Level 4-Default
0
0
1
1
0
0
0
0
Level 5
0
1
0
0
0
0
0
0
Level 6
0
1
0
1
0
0
0
0
Level 7
0
1
1
0
0
0
0
0
Level 8
0
1
1
1
0
0
0
0

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Model
Level
Heat (SA2)
Cool (SA1)
GMH48-60MSK4DH1(48K)
Level 1
1
0
0
0
0
0
0
0
Level 2
1
0
0
1
0
0
0
0
Level 3 1 0 1 0 0 0 0 0
Level 4-Default
1
0
1
1
0
0
0
0
Level 5
1
1
0
0
0
0
0
0
Level 6
1
1
0
1
0
0
0
0
Level 7
1
1
1
0
0
0
0
0
Level 8
1
1
1
1
0
0
0
0
GMH48-60MSK4DH1(60K)
Level 1
0
0
0
0
0
0
0
0
Level 2
0
0
0
1
0
0
0
0
Level 3
0
0
1
0
0
0
0
0
Level 4-Default
0
0
1
1
0
0
0
0
Level 5 0 1 0 0 0 0 0 0
Level 6
0
1
0
1
0
0
0
0
Level 7
0
1
1
0
0
0
0
0
Level 8
0
1
1
1
0
0
0
0
NOTE: 0 means dip switch to ‘on’, 1 means dip switch to number.
2.7 Fan Performance Data
External static pressure should stay within the minimum and maximum limits
shown in the table below in order to ensure proper operation of both cooling, heating,
and electric heating operation.
Model
GMH24-36MSK4DH1(24K)
Level
Static pressure(Inches W.C.)
0
0.1
0.15
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Speed 1(CFM)
1030
900
840
-
-
-
-
-
-
-
-
-
Speed 2(CFM)
1080
960
900
840
-
-
-
-
-
-
-
-
Speed 3(CFM)
1220
1120
1060
990
850
-
-
-
-
-
-
-
Speed 4(CFM)
1390
1290
1240
1180
1070
960
-
-
-
-
-
-
Speed 5(CFM)
1580
1490
1440
1390
1290
1180
1090
970
830
-
-
-
Speed 6(CFM)
1720
1640
1600
1550
1450
1360
1250
1130
960
-
-
-
Speed 7(CFM)
1800
1730
1680
1630
1550
1460
1370
1270
1150
970
830
Speed 8(CFM)
1850
1820
1790
1740
1660
1580
1500
1410
1340
1200
1080
930

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NOTE: Please refer to above table for fan speed selection, and ‘-’ is not allowed to be
used.
Model GMH24-36MSK4DH1(36K)
Level Static pressure(Inches W.C.)
0 0.1 0.15 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Speed 1(CFM)
1150
1050
950
880
-
-
-
-
- - -
-
Speed 2(CFM)
1200
1100
1000
940
850
-
-
-
- - -
-
Speed 3(CFM)
1380
1260
1200
1100
950
-
-
-
-
-
- -
Speed 4(CFM)
1550
1460 1390 1310 1160 1010 830
-
-
-
- -
Speed 5(CFM)
1710
1650 1600 1560 1480 1400 1310 1210 1080 930 - -
Speed 6(CFM)
1840
1800 1750 1710 1640 1590 1500 1420 1330 1220 1100 960
Speed 7(CFM)
1870
1830 1810 1800 1760 1690 1620 1520 1440 1350 1250 1150
Speed 8(CFM)
1900
1860 1840 1830 1790 1720 1660 1600 1540 1440 1320 1220
Model
GMH48-60MSK4DH1(48K)
Level
Static pressure(Inches W.C.)
0
0.1
0.15
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Speed 1(CFM)
1640
1500
1450
1350
-
-
-
-
-
-
-
-
Speed 2(CFM)
1680
1560
1500
1380
1300
-
-
-
-
-
-
-
Speed 3(CFM)
1810
1690
1620
1550
1380
-
-
-
-
-
-
-
Speed 4(CFM)
1930
1830
1770
1710
1580
1430
1280
-
-
-
-
-
Speed 5(CFM)
2200
2110
2040
1980
1860
1720
1620
1490
1380
-
-
-
Speed 6(CFM)
2240
2190
2145
2100
2010
1870
1750
1615
1500
1380
-
-
Speed 7(CFM)
2280
2240
2200
2180
2130
2080
2000
1880
1750
1600
1420
Speed 8(CFM)
2300
2260
2220
2190
2140
2090
2040
1980
1930
1800
1700
1550
Model
GMH48-60MSK4DH1(60K)
Level
Static pressure(Inches W.C.)
0
0.1
0.15
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Speed 1(CFM)
1660
1540
1470
1400
-
-
-
-
-
-
-
-
Speed 2(CFM)
1850
1720
1650
1600
1400
-
-
-
-
-
-
-
Speed 3(CFM)
1920
1800
1730
1650
1480
1315
-
-
-
-
-
-
Speed 4(CFM)
2110
2000
1950
1860
1760
1640
1490
1325
-
-
-
-
Speed 5(CFM)
2250
2200
2190
2140
2040
1930
1800
1670
1520
1370
-
-
Speed 6(CFM)
2260
2220
2200
2170
2090
2010
1910
1760
1650
1550
1430
1380
Speed 7(CFM)
2300
2260
2230
2200
2150
2115
2050
1990
1920
1840
1750
1660
Speed 8(CFM)
2320
2280
2250
2230
2190
2140
2080
2040
2000
1950
1920
1890

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3 Preparative for Installation
3.1 Pre-Installation Instruction
3.1.1 Checking Product Received
After receiving the product, please check if there is any damage caused by
transportation. Shipping damage is the responsibility of the carrier. Verify the model
number, specifications and accessories are correct prior to installation. The distributor
or manufacturer will not accept claims from dealers for transportation damage or
installation of incorrectly shipped units.
3.1.2 Before Installation
Carefully read all instructions for the installation prior to installing product. Make
sure each step or procedure is understood and any special considerations are taken
into account before starting installation. Assemble all tools, hardware and supplies
needed to complete the installation. Some items may need to be purchased locally.
Make sure everything needed to install the product is on hand before starting.
3.1.3 Codes & Regulations
This product is designed and manufactured to comply with national codes. It is
installer’s responsibilities to install the product in accordance with such codes and/or
any prevailing local codes/regulations. The manufacturer assumes no responsibilities
for equipment installed in violation of any codes or regulations.
3.1.4 Replacement Parts
When reporting shortages or damages, or ordering repair parts, give the complete
product model and serial numbers as stamped on the product. Replacement parts for
this product are available through your contractor or local distributor.
3.2 Important Safety Instructions
Recognize safety symbols, words, and labels
The following symbols and labels are used throughout this manual to indicate
immediate or potential hazards. It is the owner’s responsibility to read and comply with
all safety information and instructions accompanying these symbols. Failure to heed
safety information increases the risk of serious personal injury or death, property
damage and/or product damage.

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Immediate hazards which will result in property damage, product
damage, severe personal injury or death.
Hazards or unsafe practices could result in property damage,
product damage, severe personal injury or death.
Hazards or unsafe practices which may result in property damage,
product damage, severe personal injury or death.
Before serving or installing this equipment. The electrical power to
this unit must be in the “off” position. Caution, more than one disconnect may exist.
Failure to observe this warning may result in an electrical shock that can cause
personal injury or death.
The United States Environmental Protection Agency (“EPA”) has issued various
regulations regarding the introduction and disposal of refrigerants introduced into this
unit. Failure to follow these regulations may harm the environment and can lead to the
imposition of substantial fines. These regulations may vary due to the passage of laws.
A certified technician must perform the installation and service of this product. Should
questions arise, contact your local EPA office.
Due to high system pressure and electrical shock in potential, installation and
service work can be dangerous. Only trained and qualified persons are permitted to
install or service this equipment. Observe all warnings contained in this manual and
labels/tags attached to the equipment.
This product is factory shipped for use with a 208/230V-1Ph-60Hz electrical power
supply. This air handler must not be reconfigured to operate with any other power
supply.
The unit must have an uninterrupted, unbroken electric grounding to minimize the
possibility of personal injury if an electric fault occurs. The electric grounding circuit may
consist of an appropriate sized power cord which connected with the grounding piece
located in the unit control box and also connecting to the building electric service panel.
Other methods of grounding are permitted if performed in accordance with the “National
Electric Code” (NEC)/ “American National Standards Institute” (ANSI)/ “National Fire

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Protection Association” (NFPA) 70 and local/state codes. In Canada, electric grounding
conforms to the Canadian electric code CSA c22.1. Failure to observe this warning can
result in electrical shock that can cause personal injury.
Special warning for installation of furnaces or air handling units in enclosed areas,
such as garages, utility rooms or parking areas.
Carbon monoxide producing devices (such as an automobile, space heater, gas
water heater, etc.) should not be operated in enclosed areas such as unventilated
garages, utility rooms or parking areas because of the danger of carbon monoxide (CO)
poisoning resulting from the exhaust emissions. If a furnace or air handler is installed in
an enclosed area such as a garage, utility room or parking area and a carbon monoxide
producing device is operated therein, there must be adequate ventilation directly to
outside.
This ventilation is necessary to avoid the danger of CO poisoning which can occur
if a carbon monoxide producing device continues to operate in the enclosed area.
Carbon monoxide emission can be (re)circulated throughout the building if the furnace
or air handler is operating in any mode.
CO can cause serious illness including permanent brain damage or death.
4 Installation
4.1 Unit Inspection
Upon delivery, inspect the unit for damage. Any damage must be reported
immediately to the carrier. Do not install such an equipment damaged by freight which
determines the integrity and safety of the unit.
Please check the equipment model number to ensure the unit is appropriately
sized for the condensing unit.

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If an incorrect unit is supplied, it must not be installed and it is to be returned to the
supplier. The manufacturer assumes no responsibility for the installation of incorrectly
delivered units. The evaporator coil contains high-pressure inert gas for holding charge.
4.2 Location
This air handler is designed for indoor installation only. Do not install
it outdoors.
When installing the air handler, take consideration to minimize the length of
refrigerant tubing as much as possible. Do not install the air handler in a location either
above or below the condenser that violates the instructions provided with the condenser.
Service clearance is to take precedence. Allow a minimum of 24” in front of the unit for
service clearance. When installing in an area directly over a finished ceiling (such as an
attic), an emergency drain pan is required directly under the unit. See local and state
codes for requirements. When installing this unit in an area that may become wet,
elevate the unit with a sturdy, non-porous material. In installations that may lead to
physical damage (i.e. a garage) it is advised to install a protective barrier to prevent
such damage.
This air handler is designed for a complete supply and return ductwork system. Do
not operate this product without all ductwork attached.
Based upon the actual conditions, if air handler is installed as Fig. A, the air
handler should be concealed in a specific room or space and make sure the air handler
is not accessible to the general public.
Based upon the actual conditions, if air handler is installed as Fig. B, make sure
that there is enough space for care and maintenance and the height between the air
handler and ground is above 2500mm. And the air handler is not accessible to the
general public. And the air handler should be maintained horizontal 5° angle to ensure
smooth drainage.

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A B
4.3 Piping Work
4.3.1 Specification of Connection Pipe
Model
External diameter (inch)
Gas pipe
Liquid pipe
GMH24-36MSK4DH1
GMH48-60MSK4DH1 Φ3/4 Φ3/8
4.3.2 Piping Preparation
4.3.2.1 Solder Connection
All cut ends are to be round, burr free, and cleaned. Failure to follow this practice
increases the chances for refrigerant leakage.

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