Carrier DesertMaster 50TJM Installation guide

Subject to change without notice
Installation, Operation and Maintenance Instructions
Manufacturing point: Jeddah, Saudi Arabia
Nearest port of embarkation: Jeddah Islamic port
Product classification: Commercial
50TJM
Nominal Cooling Capacity 15 - 28 Tons
HFC R
-
410A Refrigerant
Note: This manual discusses the Mechanical Installation of this unit, Start-up Procedures, Operating Sequences
and Service Instructions.
Read thoroughly the entire installation instruction manual before starting the unit installation, to get familiarized with
all steps and to identify if any additional reference materials as required.
The 50TJM units are single side discharge rooftop cooling unit utilizing electric heat as an option. Units are pre-
wired, pre-charged with R-410A refrigerant, and tested at the factory. These units can be placed on the side of a
building or can be placed on a roof without roof curbs. Each unit is designed to occupy a minimal space. Piping and
drain connections are readily accessible.
For a complete list of options and accessories, refer to the Product Data Catalog.
Contact your local Carrier representative for additional reference materials.
Quality Assurance
Certificate Reg. No:
04 100 950420
Package Rooftop Units
Page 1

Table of Contents
1.0 – SAFETY CONSIDERATIONS ....................................................................................................... 3
1.1 – General .............................................................................................................................3
1.2 – Installation Safety Considerations.....................................................................................3
1.3 – Warranty............................................................................................................................3
Physical Data.........................................................................................................................................5
Unit Dimensional Drawing..............................................................................................................6 – 7
2.0 – INSTALLATION.............................................................................................................................8
2.1 – Jobsite Survey...................................................................................................................8
2.2 – Plan for Unit Location........................................................................................................8
2.3 – Rig and Place Unit ............................................................................................................8
2.4 – Positioning and Clearance................................................................................................9
2.5 – Field Fabricate Ductwork ..................................................................................................9
2.6 – Make Unit Duct Connections ............................................................................................9
2.7 – Trap Condensate Drain...................................................................................................10
2.8 – Outdoor Air-Vent.............................................................................................................10
2.9 – Make Electrical Connections...........................................................................................10
Electrical Data .....................................................................................................................................11
Electrical Resistance Heater Data.....................................................................................................12
Typical Wiring Schematic...........................................................................................................13 – 14
3.0 – START–UP INSTRUCTIONS......................................................................................................15
3.1 – Unit Preparation..............................................................................................................15
3.2 – Internal Wiring.................................................................................................................15
3.3 – Compressor Mounting.....................................................................................................15
3.4 – Refrigerant Service Ports................................................................................................15
3.5 – Compressor Rotation......................................................................................................15
3.6 – Evaporator Fan ...............................................................................................................15
3.7 – Condenser Fans and Motors ..........................................................................................16
3.8 – Return – Air Filters..........................................................................................................16
3.9 – Base Unit Operation........................................................................................................16
4.0 – SERVICE .....................................................................................................................................16
4.1 – Cleaning..........................................................................................................................16
4.2 – Lubrication.......................................................................................................................16
4.3 – Evaporator Fan Performance Adjustment ......................................................................17
4.4 – Evaporator Fan Service and Replacement.....................................................................17
4.5 – Belt Tension Adjustment.................................................................................................18
4.6 – Condenser – Fan Adjustment.........................................................................................18
4.7 – Refrigerant Charge..........................................................................................................18
4.8 – Protective Devices ..........................................................................................................18
4.9 – Control Circuit, 24 – V.....................................................................................................19
5.0 – REPLACEMENT PARTS ............................................................................................................19
Fan Performance Table ..............................................................................................................20 – 23
Cooling Chart ..............................................................................................................................24 – 25
Troubleshooting..................................................................................................................................26
Start–up Check List ............................................................................................................................27
Page 2

1 –SAFETY CONSIDERATIONS
1.1 –General
Improper installation, adjustment, alteration, service, maintenance or use can cause explosion, fire,
electrical shock or other conditions which may cause personal injury or property damage. Consult a
qualified installer; service 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 the safety codes. Wear safety glasses and work gloves. Use quenching cloths for brazing
operations and have a fire extinguisher available. Read these instructions thoroughly and follow all
warnings or cautions attached to the unit. Consult local building codes for special requirements. In
absence of local codes, it is recommended that the USA standard ANSI/NFPA 70, National Electrical
Code (NEC), be followed.
It is important to 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 the signal words DANGER, WARNING, CAUTION, and NOTE.These words are used
with the safety-alert symbol. DANGER identifies the most serious hazards which will result in severe
personal injury of death. WARNING signifies hazards which could result in personal injury or death.
CAUTION is used to identify unsafe practices, which may result in minor personal injury or product
and property damage. NOTE is used to highlight suggestions which will result in enhanced
installation, reliability, or operation.
1.2 –Installation Safety Considerations
After the unit has been received and when it is ready to be installed or reinstalled, it must be
inspected for damage. If damage is detected upon receipt, immediately file a claim with the shipping
company or repair.
This machine must be installed in a location that is not accessible to the public and protected against
access by non-authorized people.
This machine must not be installed in an explosive atmosphere.
Do not remove the skid or the packaging until the unit is in its final position. These units can be moved
with a fork lift truck, as long as the forks are positioned in the right place and direction on the unit.
The units can also be lifted with slings, using only the designated lifting points marked on the unit
(labels on the chassis and a label with all unit handling instructions are attached to the unit). Use
slings with the correct capacity, and always follow the lifting instructions on the certified drawings
supplied for the unit.
Safety is only guaranteed, if these instructions are carefully followed. If this is not the case, there is a
risk of material deterioration and injuries to personnel. These units are not designed to be lifted from
above.
1.3 –Warranty
Warranty is based on the general terms and conditions of the manufacturer. Any modifications to the
design and/or installation made without discussion with Carrier and without advance written
agreement will result in the loss of the right to any warranty claims and any claim for injury to
personnel as a result of these modifications.
Page 3

Units have high ambient operation limits. If limits are exceeded, the unit will automatically lock the
compressor out of operation. Manual reset will be required to restart the compressor.
Failure to follow this warning could cause
personal injury, death and /or equipment
damage.
Failure to follow this warning could cause
personal injury or death damage.
Puron® (R-410A) refrigerant systems
operate at higher pressures than standard
R-22 systems. Do not use R-22 service
equipment or components on Puron®
refrigerant equipment.
Relieve pressure and recover all refrigerant
before system repair or final unit disposal.
Wear safety glasses and gloves when handling
refrigerants. Keep torches and other ignition
sources away from refrigerants and oils.
NOTE
IMPORTANT
Before performing service or maintenance
operations on unit, always turn off main
power switch to unit and install lockout
tag. Unit may have more than one power
switch.
Sheet metal parts may have sharp edges or
burrs. Use care and wear appropriate protective
clothing, safety glasses and gloves when
handling parts and servicing air conditioning
equipment
WARNING
WARNING
UNIT OPERATION AND SAFETY
HAZARD
PERSONAL SAFETY AND ENVIRONMENTAL
HAZARD
WARNING
CAUTION
ELECTRIC SHOCK HAZARD
CUT HAZARD
Failure to follow this warning could cause
personal injury or death.
Failure to follow this warning could cause
personal injury.
Page 4

Physical Data Table - 1
Unit 50TJM Size 18 24 28 34
Unit Dimensions
Unit Operating Weight
Compressor No. / Type
Stage Of Capacity Control (%)
Refrigerant Type
Circuts No.
Charge Per Circuit (Down / Up) -LBS 15.96 / 15.96 22.19 / 25.62 31.19 / 29.19 31.62 / 31.37
Metering Device
Filter Drier Qty / Size
High Pressure Switch (Trip / Reset) - PSIG
Low Pressure Switch (Trip / Reset) - PSIG
Freeze Protection Thermostat (Open / Close) ±1.8 0F
Coil Type
Copper Tube,
Aluminum LSW
Fins
Standard Coil Material
Qty x Rows x FPI 1 x 3 x 16 1 x 4 x 16
Qty x Face Area (ft2)
Coil Test Pressure (PSIG)
Approx. Air Flow Rate (CFM) 12000 13000 18200 16700
Quantity
Diameter (in) / No. of Blades
Motor Type
Motor HP / RPM
Coil Type
Standard Coil Material
Qty x Rows Qty x FPI
Qty x Face Area (ft
2
)
Coil Test Pressure
Drain Pan connection Size (in)
Return Air Filter Qty x Size (in)
Fan Quantity / Fan Size (in)
Fan Type
Drive Type
Motor Type
Motor BHP 4.0 7.5
Motor Frame Size / Motor Shaft Diameter (mm) 100 / 28 132 / 38
Motor Pulley Pitch Diameter (Min / Max) (in) 4.3 / 5.6
Fan RPM Range (RPM) 1030 - 745 1029 - 740
Fan Pulley Pitch Diameter (in) 8.4
Belt, Quantity...Type 1 ... BX71
Pulley Center To Center Distance(in)
Movable Pulley Maximum Full Turns From Closed
Position
Approx.Speed Change Per Full Turn Of Movable
Pulley Flange (rpm)
Factory Speed Turns Setting 1.5
Factory Belt Standard Deflection (in) @ Force (Lb) 0.39 @ 4.65 Lb 0.40 @ 6.63 Lb
Refrigeration System
Condenser Coil
Condenser Fan & Motor
Evaporator Coil
Evaporator Fan and Motor Section
0.39 @ 5.99 Lb
Induction Motor - TEFC
5.5
112 / 28
3.7 / 4.7
1041 - 753
6.6
1 ... BX66
24.4 - 27.51
6
48
4
Belt
2 x 9.75 2 x 10.3
350
3/4
4 x 33.8 x 21.7 4 x 35.4 x 21.7
1 / 15.75 x 15.75 1 / 17.7 x 17.7
Centrifugal - Forward Blade
2 x 3 x 17 2 x 4 x 17
2
30 / 4 30 / 6
Induction Motor - Totally Enclosed
1 / 950
Copper Tube, Aluminum LSW Fins.
Copper / Aluminium
2 / DMS165S
450
630 / 480
54 / 70
-18 / -14
Copper Tube, Aluminum Double Wavy Fins
Copper / Aluminium
2 x 3 x 17
1 x 26.7 2 x 28.8
50TJM Unit Physical Data (50Hz) (English)
2 / Scroll
Page - 9
Page - 9
Page - 10
Page - 10
50 / 50
Puron ® R410A
2
TXV - Adjustable
2 / DML085S
Page 5

LENGTH WIDTH DEPTH A B C D TOTAL K L M
50TJM - 18 192 178 236 254 860
50TJM - 24 197 182 241 260 880
6. Dimensions are from outside of corner post. Allow 8mm on each side for top cover drip edge.
UNIT DIMENSIONAL DRAWING: 50TJM - 18 and 50TJM - 24 (Fig - 1)
1375
1050
1050
450
UNIT
SHIPPING DIMENSIONS (mm)
CORNER WEIGHT (Kg)
CENTER OF GRAVITY (mm)
2440
2235
7. Weights are Given for aluminim evaporator and condenser coil plate fins
5. With the exception of clearance for the condenser coil and the damper / power exhaust as stated in Note no. 6, a removal fence or barricade requires no clearance.
TOP: 1829mm to assure proper condenser fan operation.
SIDE: 1219mm for Compressor, Filter and Control boxes access.
- Local codes or jurisdiction may prevail.
4. Minimum clearance:
NOTES:
REAR: 2134mm for coil removal. This dimension can be reduced to 1219mm if conditions permit coil removal from the top.
2. Center of Gravity.
3. Direction of Airflow
1. Dimensions are in millimeters.
Page 6

LENGTH WIDTH DEPTH A B C D TOTAL K L M
50TJM - 28 248 226 310 340 1125
50TJM - 34 254 231 317 348 1150
NOTES:
6. Dimensions are from outside of corner post. Allow 8mm on each side for top cover drip edge.
7. Weights are Given for aluminim evaporator and condenser coil plate fins
REAR: 2134mm for coil removal. This dimension can be reduced to 1219mm if conditions permit coil removal from the top.
TOP: 1829mm to assure proper condenser fan operation.
SIDE: 1219mm for Compressor, Filter and Control boxes access.
- Local codes or jurisdiction may prevail.
5. With the exception of clearance for the condenser coil and the damper / power exhaust as stated in Note no. 6, a removal fence or barricade requires no clearance.
1400
1350
1160
UNIT DIMENSIONAL DRAWING: 50TJM - 28 and 50TJM - 34 (Fig - 2)
UNIT
SHIPPING DIMENSIONS (mm)
CORNER WEIGHT (Kg)
CENTER OF GRAVITY (mm)
450
1. Dimensions are in millimeters.
2. Center of Gravity.
3. Direction of Airflow
4. Minimum clearance:
3200
2485
Page 7

2 – INSTALLATION
2.1 – Jobsite Survey
Complete the following checks before installation.
1. Consult local building codes or the U.S.A. National Electrical Code (Ref: ANSI/NFPA 70, [American National
Standards Institute/National Fire Protection Association], latest revision) for special installation requirements.
2. Determine unit location (from project plans) or select unit location.
3. Check for possible overhead obstructions which may interfere with unit lifting or rigging.
2.2 – Plan for Unit Location
Select a location for the unit and its support system (curb or other) that provides for the minimum clearances required
for safety. This includes the clearance to combustible surfaces, unit performance and service access below, around
and above unit as specified in Fig - 3. For the centre of gravity coordinates, the position of the unit mounting holes,
and the weight distribution points, refer to the unit dimensional drawing Fig - 1 and Fig - 2.
Fig. 3 Unit Clearance Diagram
NOTES:
1. Minimum clearance:
REAR: 2134mm for coil removal. This dimension can be reduced to 1219mm if conditions permit coil
removal from the top.
TOP: 1829mm to assure proper condenser fan operation.
SIDE: 1219mm for Compressor, Filter and Control boxes access.
- Local codes or jurisdiction may prevail.
2. With the exception of clearance for the condenser coil and the damper / power exhaust as stated in Note no. 3, a
removal fence or barricade requires no clearance.
3. Dimensions are from outside of corner post. Allow 8mm on each side for top cover drip edge.
2.3 – Rig and Place Unit
Keep unit upright and do not drop. Spreader bars are not required if top crating is left on unit.
Rollers may be used to move unit across a roof Level by using unit frame as a reference; leveling tolerance is± 1/16
in. per linear ft in any direction.
Four lifting holes are provided in ends of unit base rails as shown in Fig –4 Refer to rigging instructions on unit.
Fig. 4 Rigging Diagram
Roof mount - Check building codes for weight distribution requirements. Unit weight and dimensions is shown in unit
dimensional drawing Fig 1 and Fig 2 on page 6 & 7 and table 2.
NOTE: Consider also the effect of adjacent units.
Page 8

Table – 2 Unit Weights and Dimensions
NOTES:
1. Remove boards at ends of unit and runners prior to rigging.
2. Rig by inserting hooks into unit base rails as shown. Use bumper boards for spreader bars.
2.4 – Positioning and Clearance.
Before positioning the unit, check the following:
•The permitted loading at the site is adequate or that appropriate strengthening measures have been taken.
•The unit is installed level on an even surface (maximum tolerance is 5 mm in both axes).
•Ensure access to the components (see “Unit Dimensional Drawings” Fig 1 & 2 & “Clearance Diagram” Fig 3).
•The number of support points is adequate and that they are in the right places.
•Although the unit is weatherproof guard against water from higher level runoff and overhangs.
Unit may be installed directly on wood flooring or on approved roof - covering material when roof curb is used. Do not
install unit in an indoor location. Do not locate air inlets near exhaust vents or sources of contaminated air.
2.5 – Field Fabricate Ductwork
Secure all ducts to building structure. Use flexible duct connectors between unit and ducts as required (a space for 2.5
to 3ft is required in case of repairing or replacing the blower wheel). Insulate and weatherproof all external ductwork,
joints, and roof openings with counter flashing and mastic in accordance with applicable codes. Ducts passing through
an unconditioned space must be insulated and covered with a vapor barrier.
The 50TJM units with electric heat require a 2-in.clearance for the first 24-in. of ductwork. Outlet grilles must not lie
directly below unit discharge.
2.6 – Make Unit Duct Connections
Unit is shipped for side duct connections. Ductwork openings are shown in Fig. 1 and Fig. 2.
UNIT SHIPPING DIMENSIONS
(mm)
SHIPPING
WEIGHT
UNIT DIMENSIONS (mm) UNIT WEIGHT
LENGTH
WIDTH
DEPTH
GROSS (Kg)
LENGTH
WIDTH
DEPTH
NET(Kg)
50TJM - 18
2440
2235
1375
925
2440
2182
1348
860
50TJM - 24
2440
2235
1375
945
2440
2182
1348
880
50TJM - 28
3200
2485
1400
1190
3200
2432
1374
1125
50TJM - 34
3200
2485
1400
1215
3200
2432
1374
1150
NOTE
IMPORTANT
A 90-degree elbow must be provided in drain hole and must be removed in ductwork to comply with UL
(Underwriters’ Laboratories) codes for use with electric heat.
NOTE
IMPORTANT
All units are internally isolated against vibration.
If extra isolation required, please see “Unit
Dimensional Drawing” Fig - 1 and Fig - 2 for
corner weights.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in
equipment damage.
All panels must be in place when rigging.
CAUTION
Page 9

WARNING
2.7 – Trap Condensate Drain
See Fig. 5, Fig.1 and Fig. 2 for drain pipe location. Trap should be deep enough to offset the maximum unit static
difference. Fig. 5 shows the recommended trap sizing.
Fig. 5Condensate Drain Details
2.8 – Outdoor Air-Vent
All units have a manual outdoor side vent to provide ventilation air. Side vents can admit up to 10% outdoor air into
indoor air section return-air compartment.
2.9 – Make Electrical Connections
FIELD POWER SUPPLY – Unit is factory wired for voltage shown on nameplate.
When installing units, provide disconnect as per NEC (National Electrical Code) requirements, of adequate size. All
field wiring must comply with NEC and local requirements. Route power lines through the corner post openings as
shown in Fig. 1 and Fig. 2.
Operating voltage to compressor must be within voltage range indicated on unit nameplate. On 3-phase units,
voltages between phases must be balanced within 2% and the current must be balanced within 10%.
FIELD CONTROL WIRING – Install a Carrier approved accessory thermostat assembly according to the installation
instructions included with the accessory. Locate thermostat assembly on a solid wall in the conditioned space to sense
average temperature. Route thermostat cable or equivalent single leads of no. 18 AWG (American Wire Gage)
colored wire from sub-base terminals through conduit in unit to low-voltage connection. Settings may be changed
slightly to provide a greater degree of comfort for a particular installation.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
The correct power phasing is critical in the operation of the scroll compressors. An incorrect phasing will cause the compressor
to rotate in the wrong direction. This may lead to premature compressors failure.
ELECTRIC SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
Do not use gas piping as an electrical ground. Unit cabinet must have an uninterrupted, unbroken electrical ground to minimize
the possibility of personal injury if an electrical fault should occur. This ground may consist of electrical wire connected to unit
ground lug in control compartment, or conduit approved for electrical ground when installed in accordance with local electrical
codes or in absence of local codes, it is recommended that U.S.A standard ANSI/NFPA 70, National Electrical Code be followed.
NOTE
IMPORTANT
For wire runs up to 50 ft, use no. 18 AWG insulated wire. For 50 to 75 ft, use no. 16 AWG insulated wire. For over 75 ft, use no.
14 AWG insulated wire. All wire larger than no. 18 AWG cannot be directly connected to the thermostat and will require a
junction box and splice at the thermostat.
Page 10

RLA LRA RLA LRA Qty HP FLA HP FLA Appl.
KW
FLA
360 440 400 / 3 / 50 12.2 101 12.2 101 2 1 3.4 Std. Eff. 46.3 - -
40.6 50
360 440 400 / 3 / 50 12.2 101 12.2 101 2 1 3.4 High Eff. 46.15 - - 40.4 50
360 440 400 / 3 / 50 12.2 101 12.2 101 2 1 3.4 Std. Eff. 46.3 21 30.3 44.2 50
360 440 400 / 3 / 50 12.2 101 12.2 101 2 1 3.4 High Eff. 46.15 21 30.3 44.0 50
360 440 400 / 3 / 50 16.7 111 16.7 111 2 1 3.4 Std. Eff. 5.5 8.3 - - 52.7 60
360 440 400 / 3 / 50 16.7 111 16.7 111 2 1 3.4 High Eff. 5.5 8 - - 52.4 60
360 440 400 / 3 / 50 16.7 111 16.7 111 2 1 3.4 Std. Eff. 5.5 8.3 28 40.4 58.8 90
360 440 400 / 3 / 50 16.7 111 16.7 111 2 1 3.4 High Eff. 5.5 828 40.4 58.5 90
360 440 400 / 3 / 50 17.9 118 17.9 118 2 1 3 Std. Eff. 5.5 8.3 - - 57.6 70
360 440 400 / 3 / 50 17.9 118 17.9 118 2 1 3 High Eff. 5.5 8 - - 57.3 70
360 440 400 / 3 / 50 17.9 118 17.9 118 2 1 3 Std. Eff. 5.5 8.3 28 40.4 61.8 100
360 440 400 / 3 / 50 17.9 118 17.9 118 2 1 3 High Eff. 5.5 828 40.4 61.5 100
360 440 400 / 3 / 50 21.8 140 21.8 140 2 1 3 Std. Eff. 7.5 11.3 - - 66.4 80
360 440 400 / 3 / 50 21.8 140 21.8 140 2 1 3 High Eff. 7.5 11 - - 66.1 80
360 440 400 / 3 / 50 21.8 140 21.8 140 2 1 3 Std. Eff. 7.5 11.3 28 40.4 66.4 100
360 440 400 / 3 / 50 21.8 140 21.8 140 2 1 3 High Eff. 7.5 11 28 40.4 66.1 100
Legend and Notes for Electrical Data Table
HACR - Heating, Air-Conditioning and Refrigeration
AB = 392v
BC = 404v
AC = 395v 1191
3
(AB) 397 - 392 =5v
(BC) 404 - 397 =7v
(AC) 457 - 397 =2v
7
397
MCA MOCP◊
18
50TJM Size 18 - 34 Compressor OFM
IFM Type
Unit Size
50TJM Min Voltage Max Voltage
Power
Supply
V / Ph / Hz
No.1 No.2
Determine Percentage Voltage Imbalance.
FLA - Full Load Amps
= 100 X
IFM -
Indoor (Evaporator) Fan Motor
LRA - Locked Rotor Amps
Maximum Deviation is 7v.
Unbalanced 3-Phase Supply Voltage
=
Average Voltage =
Use the following formula to determine the percentage of voltage imbalance
* Application heater kW @ 400 volt (Using multiplication factor table in Electric Resistance Heater Data table on page 13)
3
Electrical Data Table - 3
24
28
34
Never operate a motor where phase imbalance in supply voltage is greater than 2%.
NEC - National Electrical Code
IFM Electric
Heater
IMPORTANT: If the supply voltage phase imbalance is more than 2% contact your local electric utility company
OFM -
Outdoor (Condenser) Fan Motor
RLA - Rated Load Amps
MCA - Minimum Circuit Amps
MOCP -
Maximum Overcurrent Protection
Example: Supply Voltage is 400V - 3ph - 50Hz
Maximum Deviation From Average Voltage
Average Voltage
◊ Fuse or HACR Circuit Breaker
= 100 X
% Voltage Imbalance
Determine maximum deviation from average voltage.
= 397V
= 1.76%
392 + 404 + 395
This amount of phase imbalance is satisfactory as it is below the maximum allowable 2%
Page 11

Cfm L/s
18 250/50 4800 2265
24 250/50 6000 2832
28 250/50 7000 3304
34 250/50 7000 3304
18
24
28
34
Stages
2
2
2
380 400 480
240 — — —
480 0.62 0.7 1
NOTE: The following equation converts kW of heat energy to Btuh: kW x 3.413 = Btuh.
50TJ600727
Electric Heater Kits
Electric Resistance Heater Data - Table 4
Size (KW)
30
MINIMUM HEATING
CFM
Unit Voltages Unit Voltages
UNIT
50TJM
HEATER kW HEATER FLA (PER STAGE) HEATER
STAGES
HEAT
PER
STAGES
460
CPHEATER036A00
CPHEATER037A00
50TJ600730
MCA calculation for 50TJM 18 - 34 size units with electric heaters over 50 kW = (1.25 x IFM amps) + (1.00 x heater FLA).
Description
NOTE: Heaters are rated at 480 V. Use the Multiplication Factors table below to determine heater capacity for your particular voltage.
40
40
50TJ601162
50TJ600730
Duct heater assembly, 50TJM 18 480 V
Heater capacity(kW) is based on heater voltage of 380v or 480v. If power distribution voltage to unit varies from heater voltage, heater kW will vary
accordindly. To Detemine heater capacity at actual unit voltage, muptiply 480v capacity by multipliers found in table " Multiplication Factors" above.
Duct heater assembly, 50TJM 28 - 34 480 V
EXAMPLE: 30 kW (at 480 v) heater o
= 30.0 (0.7 multiplication factor)
= 21kW
50TJ600287
Heater
Rating
Voltage
Kit Ordering No
Multiplication Factors
Duct heater assembly, 50TJM 24 480 V
ACCESSORY HEATER PART NUMBER
Actual Heater Voltage
UNIT
50TJM
400V
Complete Kit P.N. Casing P.N. Heater Element P. N.
( 1 Per Kit ) ( 2 Per Kit )
50TJ600287
50TJ601162 50TJ600289
28kW
37kW
460
17.3
23
Page 12

Page 13
Fig. - 6

Page 14
Fig. - 7

3 – START-UP INSTRUCTIONS
Use the following instructions and start-up checklist provided on the last page to check out the unit PRIOR to unit
start-up.
3.1– Unit Preparation
Check that unit has been installed in accordance with these installation instructions and all applicable codes.
3.2 – Internal Wiring
Check all electrical connections in unit control boxes; tighten as required.
3.3 – Compressor Mounting
Compressors are internally spring mounted. Do not loosen or remove compressor hold down bolts.
3.4 – Refrigerant Service Ports
Each refrigerant system has a total of 3 Schrader type Service gage ports. One port is located on the suction line,
one on the compressor discharge line, and one on the liquid line. In addition Schrader-type valves are located
underneath the pressure switches. Be sure that caps on the ports are tight.
3.5 – Compressor Rotation
It is important to be certain the compressors are rotating in the proper direction. To determine whether or not
compressors are rotating in the proper direction:
1. Connect service gages to suction and discharge pressure fittings.
2. Energize the compressor.
3. The suction pressure should drop and the discharge pressure should rise, as is normal on any start-up.
If the suction pressure does not drop and the discharge pressure does not rise to normal levels:
1. Note that the evaporator fan is probably also rotating in the wrong direction.
2. Turn off power to the unit.
3. Reverse any two of the compressor lead wires.
4. Turn on power to the compressor.
5. Check also phase monitor all ok green led before proceeding.
The suction and discharge pressure levels should now move to their normal start-up levels.
3.6 - Evaporator Fan
Fan belt and variable pulleys are factory installed. Remove tape from the fan pulley. See Table 5 for Air Quantity
Limits. See Table 7 for Fan Performance data. Be sure that fans rotate in the proper direction. See Table 6 for Fan
RPM at various fan motor pulley settings. To alter fan performance, see Evaporator Fan Performance Adjustment
section.
Unit Cooling Electric Heaters
Minimum Maximum Minimum Maximum
50TJM-18 4,000 7,000 4,800 7,000
50TJM-24
5,000 7,500 6,000 7,500
50TJM-28 5,000 8,500 7,000 8,500
50TJM-34 7,000 10,000 7,000 10,000
Table 5 – Air Quantity Limits.
NOTE
IMPORTANT
When compressors are rotating in the wrong direction, the unit will have increased noise levels and will not provide heating and
cooling. After a few minutes of reverse operation, the scroll compressor internal overload protection will open, which will activate
the unit’s lockout and requires a manual reset. Reset accomplished by turning the thermostat on and off.
Page 15

Bold Fan RPM is Factory Setting
Table 6 – Fan RPM at Motor Pulley Settings.
3.7– Condenser Fans and Motors
Fans and motors are factory set. Refer to Condenser-Fan Adjustment Section as required.
3.8– Return – Air Filters
Check that correct filters are installed in filter tracks. See Table 1 “Physical data”. Do not operate unit without
return–air filters.
3.9 – Base Unit Operation
COOLING, UNITS — when thermostat calls for cooling, terminals G and Y1 are energized. The indoor (evaporator)
fan contactor (IFC), and compressor contactor no. 1 (C1) are energized and evaporator-fan motor, compressor no. 1
and condenser fans start. The condenser-fan motors run continuously while unit is cooling. If the thermostat calls for
a second stage of cooling by energizing Y2, compressor contactor no. 2 (C2) is energized and compressor no. 2
starts.
HEATING, UNITS — (If Accessory or Optional Heater is installed) — upon a call for heating through terminal W1,
IFC and heater contactor no. 1 (HC1) are energized.
4.0 – SERVICE
4.1 – Cleaning
Inspect unit interior at beginning of each heating and cooling season and as operating conditions require. Remove
unit top panel and/or side panels for access to unit interior.
EVAPORATOR COIL — Clean as required with a commercial coil cleaner.
CONDENSER COIL — Clean condenser coil annually and as required by location and outdoor-air conditions.
Inspect coil monthly — clean as required.
CONDENSATE DRAIN — Check and clean each year at start of cooling season.
FILTERS — Clean or replace at start of each heating and cooling season, or more often if operating conditions
require. Refer to Table 1 “Physical Data” type and size.
4.2 – Lubrication
Compressors are charged with the correct amount of oil at the factory.
Replacing Compressor - In the case of a motor burnout, the majority of contaminated will be removed with the
compressor. The rest of the oil is cleaned through the use of suction and liquid line filter driers. A 100% activated
alumna suction line filter drier is recommended but must be removed after 72 hours.
The compressor contains POE oil. POE oil has a high affinity for moisture. Do not remove the compressor’s tube
plugs until ready to insert the unit suction and discharge tube ends. The discharge connection plug should be
removed first before pulling the suction connection plug to allow the dry air pressure inside the compressor to
escape.
Note: This is only valid for the R410A systems.
Freq. Unit
50TJM
MOTOR PULLEY TURNS OPEN
0
1/2
1
1 1/2
2
2 1/2
3
3 1/2
4
4 1/2
5
5 1/2
6
50Hz
18
- - 1030 1001 978 946 918 884 860
830
804
775
745
24
- - 1041 1011 989 956 928 894 870
839
813
784
753
28
- - 1041 1011 989 956 928 894 870
839
813
784
753
34
1029
996
960
928
902
875
847
830
813
791
774
757
740
Page 16

CONDENSER AND EVAPORATOR-FAN MOTOR BEARINGS – The condenser and evaporator-fan motors have
permanently-sealed bearings, so no field lubrication is necessary.
4.3 – Evaporator Fan Performance Adjustment
NOTE: To remove belts only, follow Steps 1, 2 & 6. Fan motor pulleys are factory set speed shown in Table 6.
To change fan speeds:
1. Shut off unit power supply.
2. Loosen belt by loosening fan motor mounting plate nuts. Slide the Motor and remove belt.
3. Loosen movable-pulley flange setscrew (see Fig. 8).
4. Screw movable flange toward fixed flange to increase speed and away from fixed flange to decrease speed.
Increasing fan speed increases load on motor. Do not exceed maximum speed specified in Table 6. See Table 7 for
air flow.
5. Set movable flange at nearest keyway of pulley hub and tighten setscrew. (See Table 1 & 6 for speed change for
each full turn of pulley flange.)
6. Replace and tighten belts. See Belt Tension Adjustment section on table 1.
To align fan and motor pulleys:
1. Loosen fan pulley setscrews.
2. Slide fan pulley along fan shaft.
3. Make angular alignment by loosening motor from mounting plate.
4.4 – Evaporator Fan Service and Replacement
1. Remove supply-air section panel (The bolts holding the flexible connection to the panel should be removed).
2. Remove the Control Side panel.
3. Remove the Belt (refer to the previous section for Belt removal).
4. Remove the locking device of the hub & shaft from the both sides; it can be accessed throw the fan side panel.
5. Pull the shaft gently from the control side, the blower will fall inside the blower housing.
6. Loosen the (lower) first two bolts from each side of the scroll fan housing mid-plate. This can be done from the
supply panel side, now the fan can be removed easily from the supply panel side.
7. To assemble the fan, reverse the above procedure.
Fig. 8 Evaporator – Fan Pulley Alignment and Adjustment
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in damage to components.
1. The compressor is in a Puron® refrigerant system and uses a (POE) lubricant Emkarate RL 32 3MAF. In
the field the oil level could be topped up with Mobil EAL Arctic 22 CC if 3MAF is not available. POE oil is
extremely hygroscopic, meaning it absorbs water readily. POE oils can absorb 15 times as much as
other oils designed for HCFC and CFC refrigerants. Avoid exposure of the oil to the atmosphere.
2. Ensure that system is not subjected to liquid abuse. Turn the crankcase heater on 12 hours before
starting the compressor.
Page 17

4.5 – Belt Tension Adjustment
To adjust belt tension:
1. Loosen fan motor bolts.
2. Adjust belt tension by sliding the motor on the mounting base.
3. Tighten nuts.
4. Adjust bolts and nut on mounting plate to secure motor in fixed position.
4.6 – Condenser-Fan Adjustment
1. Shut off unit power supply.
2. Remove fan top-grille assembly and loosen fan hub screws.
3. Adjust fan height on unit, using a straightedge placed across the fan orifice.
4. Tighten setscrews
Fig. 9 Condenser - Fan Adjustment
4.7 – Refrigerant Charge
Amount of refrigerant charge is listed on unit nameplate and in Table 1. Refer to Carrier GTAC II; Module 5;
Charging, Recovery, Recycling, and Reclamation section for charging methods and procedures. Unit panels must be
in place when unit is operating during charging procedure.
NOTE: Do not use recycled refrigerant as it may contain contaminants.
NO CHARGE — Use standard evacuating techniques. After evacuating system, weight in the specified amount of
refrigerant (refer to Table 1).
LOW CHARGE COOLING — Using cooling charging chart (see Fig. 10 to 13 according to the size of the unit) Add
or remove refrigerant until conditions of the chart are met. Note that charging chart is different from those normally
used. An accurate pressure gage and temperature-sensing device is required. Charging is accomplished by
ensuring the proper amount of liquid sub-cooling. Measure liquid line pressure at the liquid line service valve using
pressure gage.
Connect temperature sensing device to the liquid line near the liquid line service valve and insulate it so that outdoor
ambient temperature does not affect reading.
TO USE THE COOLING CHARGING CHART — Use the above temperature and pressure readings, and find the
intersection point on the cooling charging chart. If intersection point on chart is above line, add refrigerant. If
intersection point on chart is below line, carefully recover some of the charge. Recheck suction pressure as charge
is adjusted.
NOTE: Indoor-air CFM must be within normal operating range of unit. All outdoor fans must be operating.
4.8 – Protective Devices
COMPRESSOR PROTECTION – Each compressor is internally protected against over temperature.
Compressor Lockout — If any of the safeties (high-pressure, low-pressure, compressor internal thermostat, external
compressor thermal overload) trip, the CLO (compressor lockout) will lock the compressors off.
To reset, manually move the thermostat setting.
Page 18

EVAPORATER AND CONDENSER-FAN MOTOR PROTECTION — Each Evaporator and Condenser-fan motor is
internally protected against over temperature.
HIGH- AND LOW-PRESSURE SWITCHES — If either switch trips, or if the compressor over temperature switch
activates, that refrigerant circuit will be automatically locked out by the CLO. To reset, manually move the thermostat
setting.
FREEZE PROTECTION THERMOSTAT (FPT) — An FPT is located on the top and bottom of the evaporator coil. It
detects frost build-up and turns off the compressor, allowing the coil to clear. Once the frost has melted, the
compressor can be reenergized.
4.9 – Control Circuit, 24-V
This control circuit is protected against over-current by a 3.2-amp circuit breaker. Breaker can be reset. If it trips,
determine cause of trouble before resetting.
5.0 – REPLACEMENT PARTS
A complete list of replacement parts may be obtained from any Carrier distributor.
NOTE
IMPORTANT
After prolonged shutdown or servicing in cold weather, energize the crankcase heaters for 12 hours before
starting the compressors.
Page 19

Fan Performance Table - 7
RPM KWI BHP RPM KWI BHP RPM KWI BHP RPM KWI BHP RPM KWI BHP
4000 555 0.93 1.04 622 1.13 1.27 686 1.36 1.52 747 1.59 1.78 804 1.84 2.06
4500 589 1.20 1.34 652 1.42 1.59 711 1.65 1.86 767 1.90 2.14 823 2.17 2.43
5000 624 1.51 1.69 682 1.75 1.96 737 2.01 2.25 790 2.27 2.54 841 2.54 2.85
5500 658 1.87 2.10 711 2.13 2.39 762 2.40 2.69 813 2.68 3.00 861 2.96 3.32
6000 689 2.28 2.56 739 2.55 2.86 788 2.83 3.18 835 3.13 3.51 881 3.43 3.85
6500 721 2.74 3.07 765 3.01 3.38 811 3.31 3.71 855 3.62 4.06 899 3.93 4.41
7000 745 3.20 3.59 788 3.49 3.92 830 3.80 4.26 873 4.12 4.62 914 4.45 4.99
RPM KWI BHP RPM KWI BHP RPM KWI BHP RPM KWI BHP RPM KWI BHP
4000 859 2.09 2.35 910 2.43 2.72 959 2.62 2.94 1007 2.90 3.25 1052 3.18 3.57
4500 875 2.44 2.73 924 2.72 3.05 971 3.00 3.37 1018 3.29 3.70 1062 3.60 4.04
5000 891 2.83 3.17 939 3.13 3.51 986 3.43 3.85 1030 3.74 4.20 1073 4.06 4.55
5500 909 3.27 3.66 955 3.58 4.01 998 3.89 4.36 1042 4.23 4.74 1083 4.56 5.11
6000 925 3.74 4.20 969 4.07 4.56 1012 4.40 4.94 1054 4.75 5.32 1094 5.10 5.72
6500 942 4.26 4.78 983 4.60 5.15 1024 4.94 5.54 1065 5.30 5.94 1104 5.66 6.35
7000 954 4.79 5.37 994 5.13 5.76 1034 5.49 6.16 1072 5.86 6.57 1110 6.24 7.00
RPM KWI BHP RPM KWI BHP RPM KWI BHP RPM KWI BHP RPM KWI BHP
4000 555 0.87 1.02 622 1.06 1.25 686 1.27 1.50 747 1.49 1.75 804 1.72 2.03
4500 589 1.12 1.32 652 1.33 1.57 711 1.55 1.83 767 1.79 2.10 823 2.03 2.39
5000 624 1.42 1.67 682 1.64 1.93 737 1.88 2.21 790 2.13 2.50 841 2.39 2.81
5500 658 1.76 2.07 711 2.00 2.35 762 2.25 2.65 813 2.51 2.95 861 2.78 3.27
6000 689 2.14 2.52 739 2.39 2.81 788 2.66 3.12 835 2.94 3.45 881 3.22 3.79
6500 721 2.57 3.02 765 2.83 3.32 811 3.11 3.65 855 3.40 3.99 899 3.69 4.34
7000 745 3.01 3.53 788 3.28 3.86 830 3.57 4.19 873 3.87 4.55 914 4.18 4.91
RPM KWI BHP RPM KWI BHP RPM KWI BHP RPM KWI BHP RPM KWI BHP
4000 859 1.96 2.31 910 2.28 2.68 959 2.46 2.89 1007 2.72 3.20 1052 2.99 3.51
4500 875 2.29 2.69 924 2.55 3.00 971 2.82 3.31 1018 3.09 3.64 1062 3.38 3.97
5000 891 2.66 3.12 939 2.94 3.45 986 3.22 3.79 1030 3.51 4.13 1073 3.81 4.48
5500 909 3.07 3.60 955 3.36 3.95 998 3.65 4.29 1042 3.97 4.66 1083 4.28 5.03
6000 925 3.51 4.13 969 3.82 4.49 1012 4.13 4.86 1054 4.46 5.24 1094 4.79 5.63
6500 942 4.00 4.71 983 4.31 5.07 1024 4.64 5.45 1065 4.98 5.85 1104 5.32 6.25
7000 954 4.49 5.28 994 4.82 5.66 1034 5.15 6.06 1072 5.50 6.47 1110 5.86 6.88
8. Conversion - Bhp to KWI
Unit - 50TJM - 018 - 15 Tons - 50Hz (Standard Motor)
Air Flow Rate
(CFM)
Available External Static Pressure (in. wg)
Available External Static Pressure (in. wg)
0.2
0.4
0.6
0.8
1.0
1.4
1.6
1.8
2.0
Available External Static Pressure (in. wg)
Available External Static Pressure (in. wg)
0.2
Bold, Italics -
Standard Motor and Drive Package
0.4 0.6 0.8 1.0
1.2
Air Flow Rate
(CFM)
Air Flow Rate
(CFM)
Unit - 50TJM - 018 - 15 Tons - 50Hz (Standard Motor) (cont)
1.2
1.4
1.6
1.8
2.0
Unit - 50TJM - 18 - 15 Tons - 50Hz (High Efficiency Motor)
5. Extensive motor and drive testing on these units ensures that the full brake horsepower and watts range of the motor can be utilized with confidence. Using
your fan motors up to the watts or bhp rating shown will not result in nuisance tripping or premature motor failure. Unit warranty will not be affected.
6. Bold data shows the range of air flow rate for unit management system, other rpms require field-supplied drive.
7. Use of field-supplied motor may affect wiring size. Contact your Carrier representative for details.
Air Flow Rate
(CFM)
Unit - 50TJM - 18 - 15 Tons - 50Hz (High Efficiency Motor) (cont)
BHP - Brake Horsepower Input to Fan
CFM - Cubic Feet per Minute
Bold , Italics - High Efficiency Motor and Drive Package
KWI - Kilo Watts Input to Motor
RPM - Revolutions Per Minute
Legend:
Notes:
1. Do not adjust motor rpm such that motor maximum bhp and/or watts is exceeded at the maximum operatin cfm.
2. Static Pressure (i.e Filters) must be added to external static pressure before entering fan performance table.
3. Interpolation is permissible. Do not extrapolate.
4. Fan performance is based on wet coils, clean filters and casing loses.
KWI=
Bhp X 0.746
Motor efficiency
Page 20