Trane 2TTB3030A, 2TTB3018A,2TTB3024A,2TTB3030A,2TTB3036A,2TTB3042A,2TTB3048A,2TTB3060A,2TWB3018A,2TWB3024A,2TWB3030A,2TWB3036A,2TWB3042A,2TWB3048A,2TWB3060A, 2TTB3036A, 2TTB3042A, 2TTB3048A Installer's Manual

18-BC56D1-5

Installer’s Guide

Replacement Condensing Units

2TTB3/2TWB3

ALL phases of this installation must comply with NATIONAL, STATE AND LOCAL CODES

IMPORTANT — This Document is customer property and is to remain with this unit. Please return to service information

pack upon completion of work.

NOTICE:
This outdoor unit is designed as a component replacement
option for existing HCFC 22 systems. This system is
shipped with a DRY NITROGEN charge and does not contain
HCFC 22.

These instructions do not cover all variations in systems nor
provide for every possible contingency to be met in connection
with installation. All phases of this installation must comply with
NATIONAL, STATE AND LOCAL CODES. Should further

information be desired or should particular problems arise
which are not covered sufficiently for the purchaser’s
purposes, the matter should be referred to your installing
dealer or local distributor.

A. GENERAL

!

WARNING

This information is intended for use by individuals posses­sing adequate backgrounds of electrical and mechanical
experience. Any attempt to repair a central air conditioning
product may result in personal injury and or property
damage. The manufacturer or seller cannot be responsible
for the interpretation of this information, nor can it assume
any liability in connection with its use.

NOTICE:
The manufacturer has always recommended installing
approved matched indoor and outdoor systems.

The benefits of installing approved matched systems are
maximum efficiency, optimum performance and best
overall system reliability.

Check for transportation damage after unit is uncrated.
Report promptly, to the carrier, any damage found to the unit.

To determine the electrical power requirements of the unit,
refer to the nameplate of the unit. The electrical power
available must agree with that listed on the nameplate.

1

5 FT. ABOVE UNIT — UNRESTRICTED

B. LOCATION AND PREPARATION OF THE UNIT

(INFORMATION APPLICABLE TO HEAT PUMPS ONLY)

This Heat Pump has been designed and manufactured to
withstand and operate in severe winter conditions.
However, there are precautionary steps which should be
taken at the time of installation which will help assure
the efficient operation of the unit. It is recommended

that these precautions be taken for units being
installed in areas where snow accumulation and
prolonged below freezing temperatures occur.

1. Units should be elevated 3 to 12 inches above the pad or
rooftop, depending on local weather. This additional height
will allow better drainage of snow and ice (melted during
defrost cycle) prior to its refreezing. This should prevent a

build-up of ice around the unit which occurs when unit is
not elevated. Insure that drain holes in unit base pan

are not obstructed preventing draining of defrost
water.

2. If possible, avoid locations that are likely to accumulate
snow drifts. If not possible, a snow drift barrier should be
installed around the unit to prevent a build-up of snow on
the sides of the unit and should be of sufficient distance
from the unit to prevent restriction of airflow to and from
the unit. Also allow for proper maintenance space. The
barrier should be constructed of materials which will
blend in with the building design.

3. Avoid locating the unit where condensation and freezing
of defrost vapor may annoy the customer. For instance,
installing the unit under a bedroom, kitchen, or picture
window may be annoying to the customer since conden­sate and fog will occur during the defrost cycle.

4. Avoid locating the unit under the eaves or other overhead
structures as sizeable icicles may form and the unit may
be damaged by these falling icicles.

Installer’s Guide

2

(INFORMATION APPLICABLE TO ALL UNITS)

1. When removing unit from the pallet, notice the tabs on

2. The unit should be set on a level support pad at least as

3. The support pad must NOT be in direct contact with any

4. The top discharge area must be unrestricted for at least

5. When the outdoor unit is mounted on a roof, be sure the

6. The maximum length of refrigerant lines from outdoor to

7. If outdoor unit is mounted above the air handler, maxi-

NOTE:
Refer to “Refrigerant Piping Software” Pub. No. 32-3312-0*
(the position of the * denotes the latest revision number).
The outdoor unit must be properly matched to the indoor
unit. Refer to Application Bulletin # SCC-APG009-EN.

If using existing refrigerant lines make certain that all joints
are brazed, not soldered.

In scroll compressor applications, dome temperatures may
be hot. Do not touch top of compressor, may cause minor
to severe burning.

BASEPAN TAB
REMOVAL

the basepan. Remove tabs by cutting with a sharp tool as
shown in Figure 2.

large as the unit base pan, such as a concrete slab. If this
is not the application used please refer to application
bulletin SSC-APG001-EN.

structure. Unit must be positioned a minimum of 12"
from any wall or surrounding shrubbery to insure
adequate airflow. Clearance must be provided in front of
control box (access panels) & any other side requiring
service access to meet National Electrical Code. Also,
the unit location must be far enough away from any
structure to prevent excess roof run-off water from
pouring directly on the unit. Do not locate unit(s) close
to bedroom(s).

five (5) feet above the unit.

roof will support the unit’s weight. Properly selected
isolation is recommended to prevent sound or vibration
transmission to the building structure.

indoor unit should NOT exceed sixty (60) feet.

mum lift should not exceed sixty (60) feet (suction line).
If air handler is mounted above condensing unit, maxi­mum lift should not exceed sixty (60) feet (liquid line).

!

CAUTION

!

CAUTION

NOTE:
The refrigerant charge specified on the data plate is the
system charge plus 15 feet of rated line set.

C. SERVICE VALVE OPERATION

BRASS LIQUID AND GAS LINE SERVICE VALVES

The Brass Liquid and Gas Line Service Valves are factory
shipped in the seated position to hold factory nitrogen charge.
The pressure tap service port (when depressed) opens only to
the field brazing side of the valve when the valve is in the
seated position. The liquid line valve is not a back seating
valve (see WARNING below).

!

WARNING

Extreme caution should be exercised when opening the
Liquid Line Service Valve. Turn valve stem counterclock­wise only until the stem contacts the rolled edge. (See
Figure 3) No torque is required.

BRASS GAS LINE BALL SERVICE VALVE

The Brass Gas Line Ball Service Valve is shipped in the
closed position to hold the factory nitrogen charge. The
pressure tap service port (when depressed) opens only to the
field brazing side when the valve is in the closed position. The
Gas Line Ball Service Valve is full open with a 1/4 turn. See
Figure 4.

BRAZING REFRIGERANT LINES

1. Before brazing, remove plugs from external copper stub
tubes. Clean internal and external surfaces of stub tubes
prior to brazing.

2. Cut and fit tubing, minimizing the use of sharp
90° bends.

3. Insulate the entire gas line and its fittings.

4. Do NOT allow uninsulated liquid line to come in direct
contact with bare gas line.

5. Precautions should be taken to avoid heat damage
to the pressure tap valve core during brazing. It is
recommended that the pressure tap port valve
core be removed and a wet rag wrapped around
the valve body.

NOTE:
Use care to make sure that no moisture enters pressure tap
port, while wet rag is being used.

NOTE:
Precautions should be taken to avoid heat damage to
basepan during brazing. It is recommended to keep the
flame directly off of the basepan.

6. Use a Dry Nitrogen Purge and Brazing Alloy without flux
when brazing the field line to the copper factory connec­tion. Flow dry nitrogen into either valve pressure tap
port, thru the tubing and out the other port while brazing.

7. Braze using accepted good brazing techniques.

LEAK CHECK

IMPORTANT:

Replace pressure tap port valve core before attaching hoses for
evacuation.

Final refrigerant charge adjustment is necessary. Use
the Subcooling Charging procedure in the outdoor unit
Service Facts.

© 2012 Trane 18-BC56D1-5

After the brazing operation of refrigerant lines to both the
outdoor and indoor unit is completed, the field brazed
connections must be checked for leaks. Pressurize through
the service valve ports, the indoor unit and field refrigerant

Installer’s Guide

3

LIQUID LINE SERVICE VALVE

lines with dry nitrogen to 150 psi. Use soap bubbles or other
leak-checking methods to see that all field joints are leak­free! If not, release pressure; then repair!

SYSTEM EVACUATION

1. Upon completion of leak check, evacuate the refrigerant
lines and indoor coil before opening the gas and liquid
line valves.

2. Attach appropriate hoses from manifold gauge to gas
and liquid line pressure taps.

NOTE:
Unnecessary switching of hoses can be avoided and
complete evacuation of all lines leading to sealed system
can be accomplished with manifold center hose and
connecting branch hose to a cylinder of HCFC-22 and
vacuum pump.

3. The outdoor unit ships with a holding charge of dry
nitrogen. The nitrogen should be removed and the entire
system must be evacuated. Remove the refrigerant
connection seal caps and open the service gas and liquid
valves slowly to release the nitrogen from the unit.

NOTE:
A 3/16" Allen wrench is required to open liquid line service
valve. A 1/4" Open End or Adjustable wrench is required to
open gas line valve. A 3/4" Open End wrench is required to
take off the valve stem cap.

4. Attach center hose of manifold gauges to the vacuum
pump once the nitrogen pressure has been relieved.

5. Evacuate until the micron gauge reads no higher than
350 microns.

6. Close off valve to vacuum pump and observe the micron
gauge. If gauge pressure rises above 500 microns in one (1)
minute, then evacuation is incomplete or system has a leak.

7. If vacuum gauge does not rise above 500 microns in
one (1) minute, the evacuation should be complete.

8. With vacuum pump and micron gauge blanked off,
weigh in HCFC 22 refrigerant based on the outdoor
unit data plate and refrigerant line set length adjust­ments noted on page 1 of the Service Facts.

9. Close valve on HCFC-22 supply cylinder when the
appropriate refrigerant charge has been achieved.

10. Replace gas and liquid service caps. These caps MUST
BE REPLACED to prevent leaks. Replace caps by
finger tightening, then tighten an additional 1/6 turn.

GAS LINE SERVICE VALVE

If refrigerant lines are longer than 15 feet and/or a
different size than recommended, it will be necessary to
adjust system refrigerant charge upon completion of
installation. See page 6 or in the unit Service Facts.

D. ELECTRICAL CONNECTIONS

!

WARNING

When installing or servicing this equipment, ALWAYS
exercise basic safety precautions to avoid the possibility of
electric shock.

1. Power wiring and grounding of equipment must comply
with local codes.

2. Power supply must agree with equipment nameplate.

3. Install a separate disconnect switch at the outdoor unit.

4. Ground the outdoor unit per local code requirements.

5. Provide flexible electrical conduit whenever vibration
transmission may create a noise problem within the
structure.

4

GAS LINE BALL SERVICE VALVE

UNIT SIDE
OF VALVE

COOLING

CAP

PRESSURE TAP PORT

GAS LINE CONNECTION

CAP

CORE

1/4 TURN ONLY
COUNTERCLOCKWISE
FOR FULL OPEN
POSITION

VALVE STEM

BODY

18-BC56D1-5 3

Installer’s Guide

6. The use of color coded low voltage wire is recommended to
simplify connections between the outdoor unit, the
thermostat and the indoor unit.

Table 1 — NEC Class II Control Wiring

24 VOLTS

WIRE SIZE MAX. WIRE LENGTH

18 AWG 150 FT

16 AWG 225 FT.

14 AWG 300 FT.

7. Table 1 defines maximum total length of low voltage
wiring from outdoor unit, to indoor unit, and to thermostat.

8. Mount the indoor thermostat in accordance with instruc­tion included with the thermostat. Wire per appropriate
hook-up diagram (included in these instructions).

E. DEFROST CONTROL

The demand defrost control measures heat pump outdoor
ambient temperature with a sensor located outside the
outdoor coil. A second sensor located on the outdoor coil is
used to measure the coil temperature. The difference between
the ambient and the colder coil temperature is the difference
or delta-T measurement. This delta-T measurement is
representative of the operating state and relative capacity of
the heat pump system. By measuring the change in delta-T,
we can determine the need for defrost. The coil sensor also
serves to sense outdoor coil temperature for termination of
the defrost cycle.

FAULT IDENTIFICATION

A fault condition is indicated by the flashing light on the
defrost control inside the heat pump control box.

In normal operation, the defrost control light will flash once
each second. If the light is flashing more than once per second
or not at all, refer to the service manual for that unit.

PIN IDENTIFICATION (See Figure 6.)

1. TEST_COMMON (Shorting any of the other pins to this
pin causes the function of the other pin to be executed.
Leaving this pin open results in the normal mode of
operation.)

2. TST = Test (Shorting TEST_COMMON to this pin
speeds up all defrost board timings.)

(HEAT PUMPS ONLY)

3. FRC_DFT = Forced Defrost (Short TEST_COMMON to
this pin for two (2) seconds to initiate a forced defrost.
Remove the short after defrost initiates.)

DEFROST CONTROL CHECKOUT

Normal operation requires:

a. LED on board flashing 1 time/second.

b. 24V AC between R & B

c. 24V AC between Y & B with unit operating

d. Defrost initiation when FRC_DFT pin is shorted to

TEST_COMMON pin.

If a defrost control problem is suspected, refer to the service
information in control box.

F. COMPRESSOR START UP

After all electrical wiring is complete, SET THE THERMO­STAT SYSTEM SWITCH IN THE OFF POSITION SO
COMPRESSOR WILL NOT RUN, and apply power by closing
the system main disconnect switch. This will activate the
compressor sump heat (where used). Do not change the
Thermostat System Switch until power has been applied for
one (1) hour. Following this procedure will prevent potential
compressor overload trip at the initial start-up.

!

WARNING

Do NOT connect 24 VAC to T1 (ODS-A) terminal. ODS-A
thermistor WILL BE BLOWN.

G. OPERATIONAL AND CHECKOUT

PROCEDURES

Final phases of this installation are the unit Operational and
Checkout Procedures which are found in this instruction. To
obtain proper performance, all units must be operated and
charge adjustments made in accordance with procedures
found in the Service Facts.

H. ELECTRIC HEATERS

Electric heaters, if used, are to be installed in the air han­dling device according to the instructions accompanying the
air handler and the heaters.

I. START CONTROL

Some models have quick start components which are factory
installed. For models that do not have factory installed start

PIN IDENTIFICATION

6

components, provisions are made for a field installed start kit
accessory. When adding an accessory, follow the instructions
provided with the kit.

J. OUTDOOR THERMOSTAT

An outdoor thermostat TAYSTAT250B may be field installed.
For data, see wiring diagram attached to unit and instruction
sheet packaged with outdoor thermostat.

TEST_COMMON

FRC_DFT

4 18-BC56D1-5

TST

K. SEACOAST SALT SHIELD

If installed within one mile of salt water, including sea­coasts and inland waterways, models without factory sup­plied Seacoast Salt Shields require the addition of
BAYSEAC001 (Seacoast Kit) at installation time.

IMPORTANT:

See Limited Warranty information in Use and Care Manual.

L. TROUBLESHOOTING

TROUBLESHOOTING CHART — WHAT TO CHECK

SYSTEM FAULTS

REFRIGERANT CIRCUIT

Liquid Pressure Too High

Liquid Pressure Too Low

Suction Pressure Too High

Suction Pressure Too Low

Liquid Refrig. Floodback TXV System

I.D. Coil Frosting

Compressor Runs Inadequate or No Cooling

ELECTRICAL

Compressor & O.D. Fan Do Not Start

Compressor Will Not Start But O.D. Fan Runs

O.D. Fan Won’t Start

Compressor Hums But Won’t Start

Compressor Cycles on IOL

I.D. Blower Won’t Start

P - Primary Causes S - Secondary Causes

HIGH VOLTAGE WIRING

POWER SUPPLY

CONTACTOR CONTACTS

START CAPACITOR

RUN CAPACITOR

START RELAY

COMPR. IOL

P

P

P

S

P

P

P

P

P

P

SPP

P

P

P

S

REFRIGERANT UNDERCHARGE

REFRIGERANT OVERCHARGE

CONTROL TRANSFORMER

LOW VOLTAGE WIRING

P

PPS

S

INEFFICI

STUCK COMPRESSOR

LOW VOLTAGE FUSE

CONTACTOR COIL

ENT COMPRESSOR

SSPPPP

S

S

PSPSS S S S

P

Installer’s Guide

RESTRICTED O.D. AIRFLOW

EXCESSIVE EVAP. LOAD

S

S

S

O.D. AIR RECIRCULATION

NONCONDENSABLES

P

P

P

S

P

P

TXV STUCK OPEN

P

PS

P

PSS

REF. CIRCUIT RESTRICTIONS

RESTRICTED I.D. AIRFLOW

O.D. FAN SPEED

SUPERHEAT

S

S

S

S

P

S

S

S

SWITCH

S

S

S

P

S

P

S

P

S

S

Thermostat

24 VAC HOT

FAN

24 VAC
Common

SOV

COOL/HEAT
1st STAGE

HEATING
2nd STAGE

TYPICAL FIELD HOOK-UP DIAGRAMS

HEAT PUMP SYSTEMS

Indoor

Unit

R

G

R

G

B B/C

O

Y

W

W

Outdoor

Unit

R

B

O

Y

X2

Black

Thermostat

24 VAC HOT

FAN

24 VAC
Common

COOLING

HEAT

AC SYSTEMS

Indoor

Unit

R

G

R

G

B B/C

Y

W

W

Outdoor

Unit

B

Y

Notes:

1. Be sure power supply agrees with equipment nameplate.

2. Power wiring and grounding of equipment must comply with local codes.

3. Low voltage wiring to be No. 18 AWG minimum conductor.

18-BC56D1-5 5

Installer’s Guide

Installer’s Guide

SUBCOOLING CHARGING IN COOLING ABOVE 55°F OD AMBIENT

The manufacturer has always recommended installing
approved

All 13 SEER split systems are AHRI rated with only TXV
indoor systems.

The benefits of installing approved indoor and outdoor split
systems are maximum efficiency, optimum performance and
the best overall system reliability.

The following charging methods are therefore prescribed for
systems with indoor TXVs.

1. Subcooling (in the cooling mode) is the

2. For best results - the indoor temperature should be kept

3. At start-up, or whenever charge is removed or added, the

4. Measure Liquid Line Temperature and Refrigerant

5. Determine total refrigerant line length, and height (lift)

6. Determine the Design Subcool Charging Temperature

7. Locate this value in the appropriate column of the

8. When system is correctly charged, you can refer to

matched indoor and outdoor systems.

only recommended

method of charging above 55°F ambient temperatures.

between 70°F to 80°F. Add system heat if needed.

system must be operated for a minimum 20 minutes to
stabilize before accurate measurements can be made.

Pressure at service valves.

if indoor section is above the condenser.

from the unit nameplate.

Subcooling Charging Table. Locate your liquid line
temperature in the left column of the table, and the
intersecting liquid line pressure under your nameplate
subcool value column. Add refrigerant to raise the pres­sure to match the table, or remove refrigerant to lower
the pressure. Again, wait 20 minutes for the system
conditions to stabilize before adjusting charge again.

System Pressure Curves (in Service Facts) to verify
typical performance.

R-22 SUBCOOLING CHARGING TABLE

LIQUID

TEMP.

(°F)

45 89 93 96 100

50 98 102 105 109

55 107 111 115 119

60 117 121 126 130

65 128 132 137 141

70 139 144 148 153

75 151 156 161 166

80 163 168 174 179

85 176 182 187 193

90 190 196 202 208

95 205 211 217 223

100 220 226 233 239

105 236 243 249 256

110 253 260 267 274

115 271 278 285 293

120 289 297 305 313

125 309 317 325 333

DESIGN SUBCOOLING VALUES (°F)

8101214

LIQUID LINE PRESSURE (psi)

SUBCOOL CHARGING TABLE CORRECTIONS FOR LINE LENGTH AND RISE

60
50
40
30
25

Add 5 psig to Subcool Charging Table Pressure

20
15

Use Design Subcool Value from Table

10

REFRIGERANT

LINE LIFT (FEET)

Subtract 5 psig from S.C. Table Pressure

0

10 20 25 30 40 60 80

TOTAL REFRIGERANT LINE LENGTH (FEET)

6 18-BC56D1-5

Installer’s Guide

OUTLINE DRAWING

NOTE: ALL DIMENSIONS ARE IN MM (INCHES).

MODELS BASE FIG. A B C D E F G H J K

2TTB3018A 2 2 651 (25-5/8) 724 (28-1/2) 651 (25-5/8) 5/8 1/4 127 (5) 57 (2-1/4) 181 (7-1/8) 44 (1-3/4) 457 (18)

2TTB3024A 2 2 832 (32-3/4) 724 (28-1/2) 651 (25-5/8) 3/4 5/16 137 (5-3/8) 65 (2-5/8) 210 (8-1/4) 57 (2-1/4) 457 (18)

2TTB3030A 3 2 832 (32-3/4) 829 (32-5/8) 756 (29-3/4) 3/4 5/16 137 (5-3/8) 86 (3-3/8) 210 (8-1/4) 79 (3-1/8) 508 (20)

2TTB3036A 3 2 832 (32-3/4) 829 (32-5/8) 756 (29-3/4) 7/8 3/8 137 (5-3/8) 86 (3-3/8) 210 (8-1/4) 79 (3-1/8) 508 (20)

2TTB3042A 4 1 841 (33-1/8) 946 (37-1/4) 870 (34-1/4) 7/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 508 (20)

2TTB3048A 4 1 1045 (41-1/8) 946 (37-1/4) 870 (34-1/4) 1-1/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 508 (20)

2TTB3060A 4 1 1045 (41-1/8) 946 (37-1/4) 870 (34-1/4) 1-1/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 508 (20)

MODELS BASE FIG. A B C D E F G H J K

2TWB3018A 2 2 832 (32-3/4) 724 (28-1/2) 651 (25-5/8) 5/8 1/4 127 (5) 57 (2-1/4) 181 (7-1/8) 44 (1-3/4) 457 (18)

2TWB3024A 2 1 832 (32-3/4) 724 (28-1/2) 651 (25-5/8) 3/4 5/16 137 (5-3/8) 65 (2-5/8) 210 (8-1/4) 57 (2-1/4) 457 (18)

2TWB3030A 3 1 933 (36-3/4) 829 (32-5/8) 756 (29-3/4) 3/4 5/16 143 (5-5/8) 92 (3-5/8) 210 (8-1/4) 79 (3-1/8) 508 (20)

2TWB3036A 4 1 943 (37-1/8) 946 (37-1/4) 870 (34-1/4) 7/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 508 (20)

2TWB3042A 4 1 943 (37-1/8) 946 (37-1/4) 870 (34-1/4) 7/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 508 (20)

2TWB3048A 4 1 1045 (41-1/8) 946 (37-1/4) 870 (34-1/4) 1-1/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 508 (20)

2TWB3060A 4 1 1045 (41-1/8) 946 (37-1/4) 870 (34-1/4) 1-1/8 3/8 152 (6) 98 (3-7/8) 219 (8-5/8) 86 (3-3/8) 508 (20)

18-BC56D1-5 7

Installer’s Guide

MOUNTING HOLE LOCATION Note: All dimensions are in MM (Inches).

NOTE:
For model base size, see table on page 7.

CHECKOUT PROCEDURE

After installation has been completed, it is recommended that the entire system be checked against the following list:

1. Refrigerant Line, Leak checked .................................. [ ]

2. Suction Lines and Fittings properly insulated ........... [ ]

3. Have all Refrigerant Lines been secured and

isolated properly? ........................................................ [ ]

4. Have passages through masonry been sealed?
If mortar is used, prevent mortar from coming

into direct contact with copper tubing ........................ [ ]

5. Verify tightness of all electrical connects ................... [ ]

6. Observe outdoor fan during on cycle for clearance

and smooth operation .................................................. [ ]

7. Indoor coil drain line drains freely. Pour water

into drain pan .............................................................. [ ]

6200 Troup Highway
Tyler, TX 75707

The manufacturer has a policy of continuous product and product data improvement and it reserves the right
to change design and specifications without notice.

8. Supply registers and return grilles open and

unobstructed ................................................................ [ ]

9. Return air filter installed ............................................ [ ]

10. Thermostat thermometer is accurate. Check
against a reliable thermometer. Adjust per

instructions with thermostat ...................................... [ ]

11. Is correct speed tap being used?

(Indoor blower motor) .................................................. [ ]

12. Operate complete system in each mode to

insure safe operation. .................................................. [ ]

02/12