Trane TTA120D300AA Service manual

August 2009 SS-SVF15A-EN
Service Facts
Split System Cooling
Condensers
Single Compressor, R-410A
TTA120D300AA TTA120DK00AA TTA120D3H0AA TTA120DKH0AA
TTA120D30RAA TTA120DK0RAA TTA120D3HRAA TTA120DKHRAA
TTA120D30SAA TTA120DK0SAA TTA120D3HSAA TTA120DKHSAA
TTA120D30TAA TTA120DK0TAA TTA120D3HTAA TTA120DKHTAA
TTA120D30UAA TTA120DK0UAA TTA120D3HUAA TTA120DKHUAA
TTA120D30WAA TTA120DK0WAA TTA120D3HWAA TTA120DKHWAA
TTA120D400AA TTA120DW00AA TTA120D4H0AA TTA120DWH0AA
TTA120D40RAA TTA120DW0RAA TTA120D4HRAA TTA120DWHRAA
TTA120D40SAA TTA120DW0SAA TTA120D4HSAA TTA120DWHSAA
TTA120D40TAA TTA120DW0TAA TTA120D4HTAA TTA120DWHTAA
TTA120D40UAA TTA120DW0UAA TTA120D4HUAA TTA120DWHUAA
TTA120D40WAA TTA120DW0WAA TTA120D4HWAA TTA120DWHWAA

© 2009 Trane All rights reserved SS-SVF15A-EN
Warnings, Cautions and Notices
Warnings, Cautions and Notices. Note that warnings, cautions and notices appear at
appropriate intervals throughout this manual. Warnings are provided to alert installing contractors
to potential hazards that could result in personal injury or death. Cautions are designed to alert
personnel to hazardous situations that could result in personal injury, while notices indicate a
situation that could result in equipment or property-damage-only accidents.
Your personal safety and the proper operation of this machine depend upon the strict observance
of these precautions.
Important
Environmental Concerns!
Scientific research has shown that certain man-made chemicals can affect the earth's naturally
occurring stratospheric ozone layer when released to the atmosphere. In particular, several of the
identified chemicals that may affect the ozone layer are refrigerants that contain Chlorine, Fluorine
and Carbon (CFCs) and those containing Hydrogen, Chlorine, Fluorine and Carbon (HCFCs). Not all
refrigerants containing these compounds have the same potential impact to the environment.
Trane advocates the responsible handling of all refrigerants-including industry replacements for
CFCs such as HCFCs and HFCs.
Responsible Refrigerant Practices!
Trane believes that responsible refrigerant practices are important to the environment, our
customers, and the air conditioning industry. All technicians who handle refrigerants must be
certified. The Federal Clean Air Act (Section 608) sets forth the requirements for handling,
reclaiming, recovering and recycling of certain refrigerants and the equipment that is used in these
service procedures. In addition, some states or municipalities may have additional requirements
that must also be adhered to for responsible management of refrigerants. Know the applicable
laws and follow them.
WARNING
Contains R-410A Refrigerant!
System contains oil and refrigerant under high pressure. Recover refrigerant to relieve pressure
before opening the system. See unit nameplate for refrigerant type. Do not use non-approved
refrigerants, refrigerant substitutes, or refrigerant additives. Use ONLY R-410A rated service
equipment or components with this unit. For specific handling concerns with R-410A, please
contact your local Trane representative. Failure to use R-410A rated service equipment or
components and/or failure to follow proper procedures or the use of non-approved refrigerants,
refrigerant substitutes, or refrigerant additives could result in death or serious injury or
equipment damage.
ATTENTION: Warnings, Cautions and Notices appear at appropriate sections throughout
this literature. Read these carefully.
WARNING: Indicates a potentially hazardous situation which, if not avoided, could
result in death or serious injury.
CAUTION: Indicates a potentially hazardous situation which, if not avoided, could
result in minor or moderate injury. It could also be used to alert against unsafe practices.
NOTICE:Indicates a situation that could result in equipment or property-damage only
accidents.

SS-SVF15A-EN 3
Warnings, Cautions and Notices
WARNING
Personal Protective Equipment (PPE) Required!
Installing/servicing this unit could result in exposure to electrical, mechanical and chemical
hazards.
• Before installing/servicing this unit, technicians MUST put on all Personal Protective
Equipment (PPE) recommended for the work being undertaken. ALWAYS refer to appropriate
MSDS and OSHA guidelines for proper PPE.
• When working with or around hazardous chemicals, ALWAYS refer to appropriate MSDS and
OSHA guidelines for information on allowable personal exposure levels, proper respiratory
protection and handling recommendations.
• If there is a risk of arc or flash, technicians MUST put on all Personal Protective Equipment (PPE)
in accordance with NFPA70E for arc/flash protection PRIOR to servicing the unit.
Failure to follow recommendations could result in death or serious injury.

4SS-SVF15A-EN
Accessories
Table 1. List of Available Accessories - TTA120D
MODEL USED WITH DESCRIPTION
Coil Guard
BAYGARD059A TTA120D Hail Guard
HOT GAS BY-PASS
BAYHGBP010A TTA120D Universal Hot Gas Bypass Kit
Trane Communication Interface
BAYICSI003A TTA120D Comm 3/4 Communications Interface
Isolators
BAYISLT005A TTA120D Rubber Isolator Kit
BAYISLT023A TTA120D Steel Spring Isolator Kit
Low Ambient
BAYLOAMU02A TTA120D On/Off Fan Control Mounted in Unit Control Box
(large cabinets)
BAYLOAM333A TTA120D3 Modulating P-66 Head Pressure Control w/ 208-230V
1 HP Hi-Eff Motor (external mount)
BAYLOAM433A TTA120D4 Modulating P-66 Head Pressure Control w/ 460V
1.0 HP Hi-Eff Motor (external mount)
LonTalk Communications Interface
BAYLTCI002B TTA120D LonTalk Communications Interface
Time Delay Relay
BAYRLAY002 TTA120D Time Delay Relay

SS-SVF15A-EN 5
Refrigerant Circuit
Figure 1.
FILTER DRIER
FILTER DRIER
NOTE A: ONLY ONE OUTDOOR AND INDOOR
NOTE A: ONLY ONE OUTDOOR AND INDOOR
COIL REFRIGERANT ENTRY AND
COIL REFRIGERANT ENTRY AND
EXIT CIRCUIT IS SHOWN. ALL
EXIT CIRCUIT IS SHOWN. ALL
MODELS HAVE MULTIPLE ENTRY
MODELS HAVE MULTIPLE ENTRY
AND EXIT CIRCUITS.
AND EXIT CIRCUITS.
TXV
TXV
S
D
COMPRESSOR
COMPRESSOR
LOW PRESSURE
LOW PRESSURE
SWITCH (LPCO)
SWITCH (LPCO)
FIELD SUPPLIED
FIELD SUPPLIED
INTER-CONNECTING
INTER-CONNECTING
TUBING
TUBING
OUTDOOR COIL
OUTDOOR COIL
INDOOR COIL
INDOOR COIL
SERVICE
SERVICE
VALV E
VALVE
SERVICE
SERVICE
VALV E
VALVE
EXPANSION
EXPANSION
VALVE BULB
VALVE BULB
EQUALIZER
EQUALIZER
TUBE
TUBE
NOTE A
NOTE A
NOTE A
NOTE A
NOTE A
NOTE A
NOTE A
NOTE A
HIGH PRESSURE
HIGH PRESSURE
SWITCH (HPCO)
SWITCH (HPCO)
GAUGE
GAUGE
CONNECTION
CONNECTION
DISCHARGE
DISCHARGE
TEMPERATURE
TEMPERATURE
LIMIT (DTL)
LIMIT (DTL)
NOTE B: DUAL CIRCUIT MODELS HAVE 2
NOTE B: DUAL CIRCUIT MODELS HAVE 2
REFRIGERATION CIRCUITS.
REFRIGERATION CIRCUITS.
AIR
AIR
AIR
AIR
SUB-COOLING CIRCUIT
SUB-COOLING CIRCUIT
GAUGE
GAUGE
CONNECTION
CONNECTION
INDICATES DIRECTION OF
INDICATES DIRECTION OF
REFRIGERANT FLOW
REFRIGERANT FLOW
COOLING ONLY CIRCUIT DIAGRAM
COOLING ONLY CIRCUIT DIAGRAM
V
V

6SS-SVF15A-EN
Product Specifications
NOTICE
Refrigerant in Crankcase!
Do not disconnect power except for safety or service. Follow these procedures prior to startup if
unit has been charged or power has been disconnected for more than 12 hours. If system has
just been charged through liquid line service valve port, an 8 hour compressor oil warming time
is not required.
Set room thermostat to “OFF” position and ensure compressor is not running.
Apply power for at least 8 hours prior to startup by closing disconnect switch. This will energize
compressor oil heater which will evaporate any liquid refrigerant in crankcase. After 8 hours the
thermostat may be set to cooling.
Failure to follow the above could result in equipment damage.
Table 2. General Data — TTA120D
10 Tons
Single Compressor
TTA120D3, D4, DW, DK
Cooling Performance
Gross Cooling Capacity
Matched Air Handler 124,000
Condensing Unit Only 112,000
ARI Net Cooling Capacity 120,000
Efficiency
Matched Air Handler (EER) 11.2
Condensing Unit Only (EER) 12.2
System Integrated Part Load Value (IPLV) N/A
System (IEER) 12.2
Condensing Unit Only (IPLV) N/A
System kW/Condensing Unit kW 10.72/9.18
Compressor
Type S cro ll
No./Tons 1/8.6
System Data
No. Refrigerant Circuits 1
Suction Line (in.) OD 1 3/8
Liquid Line (in.) OD 1/2
Outdoor Coil - Type Lanced
Tube Size (in.) OD 0.375
Face Area (sq ft) 24.0
Rows/FPI 2/18
Outdoor Fan - Type Propeller
No. Used/Diameter (in.) 1/28
Drive Type/No. Speeds Direct/1
CFM 9600
No. Motor/HP 1/1
Motor RPM 1100
Refrigerant Charge (Field Supplied)
(lbs of R410A) 22.5
Table 3. Estimated charge levels at ARI rated line lengths (25 feet)
Matched Set
Refrigerant Charge Per Circuit
Circuit 1 Circuit 2
Liquid Line
Diameter
Vapor Line
Diameter
TTA120D w/TWE120D 22.5 NA 0.5 1.375

SS-SVF15A-EN 7
Sequence of Operation
NOTICE
Equipment Damage!
Ensure the disconnect for the indoor air handler is closed before operating the system.
Operating the outdoor unit without the indoor fan energized can cause unit trip-out on high
pressure control and/or liquid flood back to the compressor.
Electromechanical Controls
General
Operation of the system cooling (and optional heating) cycles is controlled by the position of the
system switch on the room thermostat. Once the system switch is placed in either the HEAT or
COOL position, unit operation is automatic. The optional automatic changeover thermostat, when
in the AUTO position, automatically changes to heat or cool with sufficient room temperature
change.
Evaporator Fan (Indoor Supply Air)
The evaporator fan is controlled by an ON/AUTO switch on the room thermostat. With the switch
positioned at AUTO and the system operating in the cooling mode, fan operation coincides with
the cooling run cycles. If the system is equipped with heat and is operating in the heating mode
while the fan switch is at AUTO, fan operation coincides with the heating run cycles. When the fan
switch is positioned at ON, fan operation is continuous.
Cooling Mode
With the disconnect switch in the ON position, current is supplied to the compressor sump
heater(s), phase monitor and control transformer. The sump heater(s) supplies heat to the
compressor(s) during the “Off” cycle. The phase monitor looks at the incoming power to verify
that there is no reversed phase, no phase imbalance, and no loss of phase. If the phase monitor
detects any of these three conditions, it will shut off control voltage. The transformer steps down
the line voltage to 24V for the low voltage control circuit. When the room thermostat system switch
is positioned at COOL and the fan switch is at AUTO, the compressor contactor energizes on a call
for cooling. When the contacts of the compressor contactor close, operation of the compressor and
condenser fan begins. The evaporator fan contactor also energizes on a call for cooling and initiates
evaporator fan operation.
On units with dual circuits, the second stage of cooling is initiated as a result of the 2-stage
thermostat calling for additional cooling.
ReliaTel™ Controls
The ReliaTel™ Controls is a microelectronic control feature, which provides operating functions
that are significantly different than conventional Electromechanical units. The ReliaTel™
Refrigeration Module (RTRM) uses Proportional/Integral control algorithms to perform specific
unit functions that govern the unit operation in response to application conditions.
The RTRM provides compressor anti-short cycle timing functions through minimum “Off” and
“On” timing to increase reliability, performance and to maximize unit efficiency. Upon power
initialization, the RTRM performs self-diagnostic checks to ensure that all internal controls are
functioning. It checks the configuration parameters against the components connected to the
system. The system LED located on the RTRM module is turned “On” within one second after
power-up if all internal operations are okay.

8SS-SVF15A-EN
Sequence of Operation
ReliaTel™ Control Cooling Mode
For Zone Sensor Control
When the system switch is set to the COOL position and the zone temperature rises above the
cooling setpoint, the RTRM energizes the compressor contactor, provided the high and low
pressure and the discharge temperature limit controls are closed. When the compressor contacts
close, the compressor and the outdoor fan motor start to maintain the zone temperature to within
± 2°F of the sensor setpoint at the sensed location. On units with dual circuits, the second stage of
cooling is initiated as a result of the Proportional/Integral control algorithms calling for additional
cooling.
For Thermostat Control:
When the room thermostat system switch is positioned at COOL and the fan switch is at AUTO,
the RTRM energizes the compressor contactor, provided the high and low pressure and the
discharge temperature limit controls are closed. When the contacts of the compressor contactor
close, operation of the compressor and condenser fan begins. The evaporator fan contactor also
energizes on a call for cooling and initiates evaporator fan operation. On units with dual circuits,
the second stage of cooling is initiated as a result of the 2-stage thermostat calling for additional
cooling.
Note: Irregular unit operation may occur when the unit is controlled with a triac-switching
thermostat. Please review the approved thermostat vendor list for all recommended relay-
switching thermostats.
ReliaTel™ Control Evaporator Fan Operation
When the fan selection switch is set to the AUTO position, the RTRM energizes the evaporator fan
relay coil approximately 1 second after energizing the compressor contactor coil in the cooling
mode. In the heating mode, the RTRM energizes the evaporator fan relay coil approximately 1
second before energizing the electric heat contactors. The RTRM de-energizes the evaporator fan
relay coil approximately 60 seconds on dual compressor units and 80 seconds on single
compressor units after the cooling requirement has been satisfied to enhance unit efficiency. When
the heating cycle is terminated, the evaporator fan relay coil is de-energized at the same time as
the heater contactors. When the fan selection switch is set to the ON position, the RTRM keeps the
evaporator fan relay coil energized for continuous fan motor operation.
ReliaTel™ Control Heating Operation
Electric heat is factory disabled on all split system units with ReliaTel control (jumper placed
between J2-1 and J2-2 RTRM inputs). To configure the unit for electric heat, cut or remove the
jumper wire between J2-1 and J2-2 on the RTRM. All split system units with ReliaTel control are
also configured from the factory for only 1-stage of electric heat (jumper placed between J1-3 and
J1-6 RTRM inputs). To configure the unit for 2-stages of electric heat, cut or remove the jumper
placed between J1-3 and J1-6 RTRM inputs.
When the system switch is set to the HEAT position and heating is required, the RTRM energizes
the Heat 1 relay coil on the RTRM. When the Heat 1 relay contacts close, the first stage electric heat
contactor is energized. If the first stage of electric heat cannot satisfy the heating requirement, the
RTRM energizes the Heat 2 relay coil on the RTRM. When the Heat 2 relay contacts close, the second
stage electric heat contactor is energized. The first and second stages of heat are cycled “On” and
“Off” as required to maintain the zone.

SS-SVF15A-EN 9
Cooling Pressure Curves
Figure 2. TWE120D
TTA120D with TWE120D (English) TTA120D with TWE120D (Metric)
Suction Pressure at 400 CFM/Ton
100
110
120
130
140
150
160
170
55 65 75 85 95 105 115 125
Ambient DB - Degree F
Suction Pressure - psig
68/57 DB/WB
74/62 DB/WB
80/67 DB/WB
86/72 DB/WB
Suction Pressure at 400 CFM/Ton
750
800
850
900
950
1000
1050
1100
1150
13 18 24 29 35 41 46 52
Ambient DB - Degree C
Suction Pressure - kPa
20/14 DB/WB
23/17 DB/WB
27/19 DB/WB
30/22 DB/WB
Discharge Pressure at 400 CFM/Ton
200
250
300
350
400
450
500
550
600
650
55 65 75 85 95 105 115 125
Ambient DB - Degree F
Discharge Pressure - psig
68/57 DB/WB
74/62 DB/WB
80/67 DB/WB
86/72 DB/WB
Discharge Pressure at 400 CFM/Ton
1500
1750
2000
2250
2500
2750
3000
3250
3500
3750
4000
4250
4500
13 18 24 29 35 41 46 52
Ambient DB - Degree C
Discharge Pressure - kPa
20/14 DB/WB
23/17 DB/WB
27/19 DB/WB
30/22 DB/WB

10 SS-SVF15A-EN
Charging Chart
Charging Chart
Figure 3. TTA120D
TTA120D Charging Curve
200
225
250
275
300
325
350
375
400
425
450
475
500
525
550
575
600
625
650
55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140
Liquid Temperature Leaving OD Coil, °F
Discharge Pressure, psig
Add
charge
Remove
charge