Carrier 48TC series User manual

48TC
Single Package Rooftop
Gas Heating/Electric Cooling Unit
S i z e s 0 4 --- 0 7 w i t h P u r o n r(R---410A) Refrigerant
Installation Instructions
NOTE: Read the entire instruction manual before starting
the installation
TABLE OF CONTENTS
SAFETY CONSIDERATIONS 1....................
INSTALLATION 3...............................
Step 1 -- Plan for Unit Location 3..................
Step 2 -- Plan for Sequence of Unit Installation 4......
Step 3 -- Inspect unit 4...........................
Step 4 -- Provide Unit Support 4...................
Step 5 -- Field Fabricate Ductwork 6................
Step 6 -- Rig and Place Unit 6.....................
Step 7 -- Convert to Horizontal and Connect Ductwork 7
Step 8 -- Install Outside Air Hood 7................
Step 9 -- Install Flue Hood 9......................
Step 10 -- Install Gas Piping 9.....................
Step 11 -- Install External Condensate Trap and Piping 11
Step 12 -- Make Electrical Connections 12...........
Step 13 -- Adjust Factory--Installed Options 19........
Step 14 -- Install Accessories 19...................
SAFETY CONSIDERATIONS
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, 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 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 and appropriate
national electrical codes (in USA, ANSI/NFPA70,
National Electrical Code (NEC); in Canada, CSA C22.1)
for special requirements.
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 or
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.
FIRE, EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury or death.
Disconnect gas piping from unit when leak testing at
pressure greater than 0.5 psig (3450 Pa). Pressures
greater than 0.5 psig (3450 Pa) will cause gas valve
damage resulting in hazardous condition. If gas valve
is subjected to pressure greater than 0.5 psig (3450
Pa), it must be replaced before use. When pressure
testing field--supplied gas piping at pressures of 0.5
psig (3450 Pa) or less, a unit connected to such piping
must be isolated by closing the manual gas valve.
!WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could cause personal
injury or death.
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.
!WARNING

2
C08028
Fig. 1 -- Unit Dimensional Drawing
48TC

3
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal
injury, death and/or equipment damage.
Puronr(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.
!WARNING
INSTALLATION
Jobsite Survey
Complete the following checks before installation.
1. Consult local building codes and the NEC (National
Electrical Code) ANSI/NFPA 70 for special installa-
tion 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.
Step 1 — 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 unit
drawings. See Fig. 2.
18” (457)
42" (1067)
18" (457)
42" (1067)
1
Required bottom condensate drain connection.
Otherwise, 36” (914mm) for condensate connection.
1
C07459
Fig. 2 -- Service Clearance Dimensional Drawing
NOTE: Consider also the effect of adjacent units.
Be sure that unit is installed such that snow will not block
the combustion intake or flue outlet.
Unit may be installed directly on wood flooring or on
Class A, B, or C 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 other sources of contaminated
air. For proper unit operation, adequate combustion and
ventilation air must be provided in accordance with
Section 5.3 (Air for Combustion and Ventilation) of the
National Fuel Gas Code, ANSI Z223.1 (American
National Standards Institute) and NFPA (National Fire
Protection Association) 54 TIA----54----84----1. In Canada,
installation must be in accordance with the CAN1----B149
installation codes for gas burning appliances.
Although unit is weatherproof, avoid locations that permit
water from higher level runoff and overhangs to fall onto
the unit.
Locate mechanical draft system flue assembly at least 4 ft
(1.2 m) from any opening through which combustion
products could enter the building, and at least 4 ft (1.2 m)
from any adjacent building (or per local code). Locate the
flue assembly at least 10 ft (3.05 m) from an adjacent
unit’s fresh air intake hood if within 3 ft (0.91 m) of same
elevation (or per local code). When unit is located
adjacent to public walkways, flue assembly must be at
least 7 ft (2.1 m) above grade.
Select a unit mounting system that provides adequate
height to allow installation of condensate trap per
requirements. Refer to Step 11 — Install External Trap for
Condensate Drain – for required trap dimensions.
Roof mount —
Check building codes for weight distribution
requirements. Unit operating weight is shown in Table 1.
Table 1 – Operating Weights
48TC UNITS LB (KG)
Component A04 A05 A06 A07
Base Unit 483 (219) 537 (244) 569 (258) 652 (296)
Economizer
Vertical 50 (23) 50 (23) 50 (23) 50 (23)
Horizontal 80 (36) 80 (36) 80 (36) 80 (36)
Cu Fins 25 (11) 43 (20) 56 (25) 73 (33)
Powered Outlet 32 (15) 32 (15) 32 (15) 32 (15)
Curb
14---in/356 mm 110 (50) 110 (50) 110 (50) 110 (50)
24---in/610 mm 145 (66) 145 (66) 145 (66) 145 (66)
48TC

4
Step 2 — Plan for Sequence of Unit Installation
The support method used for this unit will dictate different
sequences for the steps of unit installation. For example,
on curb--mounted units, some accessories must be
installed on the unit before the unit is placed on the curb.
Review the following for recommended sequences for
installation steps.
Curb--mounted installation —
Install curb
Install field--fabricated ductwork inside curb
Install accessory thru--base service connection package
(affects curb and unit) (refer to accessory installation
instructions for details)
Prepare bottom condensate drain connection to suit
planned condensate line routing (refer to Step 11 for
details)
Rig and place unit
Install outdoor air hood
Install flue hood
Install gas piping
Install condensate line trap and piping
Make electrical connections
Install other accessories
Pad--mounted installation —
Prepare pad and unit supports
Check and tighten the bottom condensate drain
connection plug
Rig and place unit
Convert unit to side duct connection arrangement
Install field--fabricated ductwork at unit duct openings
Install outdoor air hood
Install flue hood
Install gas piping
Install condensate line trap and piping
Make electrical connections
Install other accessories
Frame--mounted installation —
Frame--mounted applications generally follow the
sequence for a curb installation. Adapt as required to
suit specific installation plan.
Step 3 — Inspect unit
Inspect unit for transportation damage. File any claim
with transportation agency.
Confirm before installation of unit that voltage, amperage
and circuit protection requirements listed on unit data
plate agree with power supply provided.
Step 4 — Provide Unit Support
Roof Curb Mount —
Accessory roof curb details and dimensions are shown in
Fig. 3. Assemble and install accessory roof curb in
accordance with instructions shipped with the curb.
NOTE: The gasketing of the unit to the roof curb is
critical for a watertight seal. Install gasket supplied with
the roof curb as shown in Fig. 3. Improperly applied
gasket can also result in air leaks and poor unit
performance.
Curb should be level. This is necessary for unit drain to
function properly. Unit leveling tolerances are show in
Fig. 4. Refer to Accessory Roof Curb Installation
Instructions for additional information as required.
Install insulation, cant strips, roofing felt, and counter
flashing as shown. Ductwork must be attached to curb and
not to the unit. The accessory thru--the--base power and
gas connection package must be installed before the unit
is set on the roof curb. If field--installed thru--the--roof
curb gas connections are desired, use factory--supplied
1/2--in. pipe coupling and gas plate assembly to mount the
thru--the--roof curb connection to the roof curb. Gas
connections and power connections to the unit must be
field installed after the unit is installed on the roof curb.
If electric and control wiring is to be routed through the
basepan, attach the accessory thru--the--base service
connections to the basepan in accordance with the
accessory installation instructions.
Slab Mount (Horizontal Units Only) —
Provide a level concrete slab that extends a minimum of 6
in. (150 mm) beyond unit cabinet. Install a gravel apron in
front of condenser coil air inlet to prevent grass and
foliage from obstructing airflow.
NOTE: Horizontal units may be installed on a roof curb
if required.
Alternate Unit Support (In Lieu of Curb or Slab
Mount) —
A non--combustible sleeper rail can be used in the unit
curb support area. If sleeper rails cannot be used, support
the long sides of the unit with a minimum of 3 equally
spaced 4--in. x 4--in. (102 mm x 102 mm) pads on each
side.
48TC

5
ROOF CURB
ACCESSORY A UNIT SIZE
CRRFCURB001A01 1-2
[356]
CRRFCURB002A01 2-0
[610]
NOTES:
1. Roof curb accessory is shipped disassembled.
2. Insulated panels.
3. Dimensions in [ ] are in millimeters.
4. Roof curb: galvanized steel.
5. Attach ductwork to curb (flanges of duct rest on
curb).
6. Service clearance: 4 ft on each side.
7. Direction of airflow.
8. Connector package CRBTMPWR001A01 is
for thru-the-curb type gas.
CRBTMPWR003A01 is for thru-the base
type gas connections.
CONNECTOR
PKG. ACCY. BC
DALT
DRAIN
HOLE
GAS POWER CONTROL ACCESSORY
POWER
CRBTMPWR001A01
1-9
11
/
16
[551]
1-4
[406]
1
3
/
4
[44.5]
3
/
4
[19] NPT
3
/
4
[19] NPT
1
/
2
[12.7]
NPT
1
/
2
[12.7]
NPT
CRBTMPWR003A01
1
/
2
[12.7] NPT
3
/
4
[19] NPT
48TC
A04-A07
C07503
Fig. 3 -- Roof Curb Details
48TC

6
MAXIMUM ALLOWABLE
DIFFERENCE IN. (MM)
A-B B-C A-C
0.5” (13) 1.0” (25) 1.0” (25)
C06110
Fig. 4 -- Unit Leveling Tolerances
Step 5 — Field Fabricate Ductwork
Cabinet return-air static pressure (a negative condition)
shall not exceed 0.35 in. wg (87 Pa) with economizer or
0.45 in. wg (112 Pa) without economizer.
For vertical ducted applications, secure all ducts to roof
curb and building structure. Do not connect ductwork to
unit.
Insulate and weatherproof all external ductwork, joints,
and roof openings with counter flashing and mastic in
accordance with applicable codes.
Ducts passing through unconditioned spaces must be
insulated and covered with a vapor barrier.
If a plenum return is used on a vertical unit, the return
should be ducted through the roof deck to comply with
applicable fire codes.
A minimum clearance is not required around ductwork.
Step 6 — 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. See Table 1 and Fig. 5 for additional
information.
Lifting holes are provided in base rails as shown in Fig. 5.
Refer to rigging instructions on unit.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in
equipment damage.
All panels must be in place when rigging. Unit is not
designed for handling by fork truck.
CAUTION
!
Before setting the unit onto the curb, recheck gasketing on
curb.
C06005
Fig. 5 -- Rigging Details
UNIT MAX WEIGHT DIMENSIONS
A B C
LB KG IN MM IN MM IN MM
48TC---A04 520 236 74.38 1888 39 991 33.38 848
48TC---A05 575 261 74.38 1888 39 991 33.38 848
48TC---A06 605 274 74.38 1888 39 991 33.38 848
48TC---A07 690 313 74.38 1888 39 991 41.38 1051
NOTES:
1. Dimensions in ( ) are in millimeters.
2. Hook rigging shackles through holes in base rail, as shown in detail “A.” Holes in base rails are centered around the
unit center of gravity. Use wooden top to prevent rigging straps from damaging unit.
3. Unit weights do not include economizer.
48TC

7
PositioningonCurb—
Position unit on roof curb so that the following clearances
are maintained: 1/4 in. (6.4 mm) clearance between the
roof curb and the base rail inside the front and rear, 0.0 in.
clearance between the roof curb and the base rail inside on
the duct end of the unit. This will result in the distance
between the roof curb and the base rail inside on the
condenser end of the unit being approximately equal to
Fig. 3, section C--C.
Although unit is weatherproof, guard against water from
higher level runoff and overhangs.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in
equipment damage.
All panels must be in place when rigging. Unit is not
designed for handling by fork truck.
CAUTION
!
Flue vent discharge must have a minimum horizontal
clearance of 4 ft (1220 mm) from electric and gas meters,
gas regulators, and gas relief equipment. Minimum
distance between unit and other electrically live parts is
48 inches (1220 mm).
Flue gas can deteriorate building materials. Orient unit
such that flue gas will not affect building materials.
Locate mechanical draft system flue assembly at least 48
in. (1220 mm) from an adjacent building or combustible
material.
NOTE: Installation of accessory flue discharge deflector
kit will reduce the minimum clearance to combustible
material to 18 in. (460 mm).
After unit is in position, remove rigging skids and
shipping materials.
Step 7 — Convert to Horizontal and Connect
Ductwork (when required)
Unit is shipped in the vertical duct configuration. Unit
without factory--installed economizer or return air smoke
detector option may be field--converted to horizontal
ducted configuration. To convert to horizontal
configuration, remove screws from side duct opening
covers and remove covers. Using the same screws, install
covers on vertical duct openings with the insulation--side
down. Seals around duct openings must be tight. See Fig.
6.
C06108
Fig. 6 -- Horizontal Conversion Panels
Field--supplied flanges should be attached to horizontal
duct openings and all ductwork should be secured to the
flanges. Insulate and weatherproof all external ductwork,
joints, and roof or building openings with counter flashing
and mastic in accordance with applicable codes.
Do not cover or obscure visibility to the unit’s informative
data plate when insulating horizontal ductwork.
Step 8 — Install Outside Air Hood
The outdoor hood components are shipped in a box
located in the unit return air compartment behind the
outdoor--ar opening access panel (or economizer). Access
is through the filter access panel. See Fig. 7.
1. To remove the existing unit filter access panel, raise
the panel and swing the bottom outward. The panel is
now disengaged from the track and can be removed.
2. To remove the component box from its shipping posi-
tion, remove the screw holding the hood box bracket
to the top of the economizer. Slide the hood box out
of the unit. See Fig. 8.
FILTER ACCESS PANEL
OUTDOOR-AIR OPENING AND
INDOOR COIL ACCESS PANEL
COMPRESSOR
ACCESS PANEL
C06023
Fig. 7 -- Typical Access Panel Locations
48TC

8
HoodBox
HOOD BOX
BRACKET
C06024
Fig. 8 -- Hood Box Removal
Motorized 2--Position Damper Hood —
1. Assemble outdoor--air hood top and side plates as
shown in Fig. 9. Install seal strips on hood top and
sides. Put aside screen retainer and screws for later
assembly.
2. Fasten hood top and side plate assembly to unit with
screws provided. See Fig. 9.
3. Slide outdoor--air inlet screen into screen track on
hood side plates. While holding screen) in place,
fasten screen retainer to hood using screws provided.
4. Replace filter access panel. See Fig. 7.
SEAL STRIP
HOOD TOP
SEAL STRIP
HOOD
SIDE
SCREEN
RETAINER
HOOD SIDE
SCREEN
TRACKS
OUTDOOR AIR INLET SCREEN
SEAL STRIP
OUTDOOR-AIR HOOD – UNASSEMBLED
HOOD SIDES AND TOP ASSEMBLED
TRACKS FOR AIR
INLET SCREEN
HOOD
SIDE
HOOD TOP
C07504
Fig. 9 -- Outdoor--Air Hood Details
Economizer Hood —
NOTE: If the power exhaust accessory is to be installed
on the unit, the hood shipped with the unit will not be
used and must be discarded. Save the aluminum filter for
use in the power exhaust hood assembly.
1. The indoor coil access panel will be used as the top of
the hood. Remove the screws along the sides and bot-
tom of the indoor coil access panel. See Fig. 10.
SIDE
PANEL
INDOOR
COIL
ACCESS
PANEL
INDOOR
COIL
ACCESS
PANEL
CAULK
HERE
TOP
SIDE
PANEL
C06025
Fig. 10 -- Indoor Coil Access Panel Relocation
2. Swing out indoor coil access panel and insert the
hood sides under the panel (hood top). Use the screws
provided to attach the hood sides to the hood top. Use
screws provided to attach the hood sides to the unit.
See Fig. 11.
3. Remove the shipping tape holding the economizer ba-
rometric relief damper in place.
4. Insert the hood divider between the hood sides. See
Fig. 11 and 12. Secure hood divider with 2 screws on
each hood side. The hood divider is also used as the
bottom filter rack for the aluminum filter.
5. Open the filter clips which are located underneath the
hood top. Insert the aluminum filter into the bottom
filter rack (hood divider). Push the filter into position
past the open filter clips. Close the filter clips to lock
the filter into place. See Fig. 12.
B
TOP
PANEL
INDOOR COIL
ACCESS PANEL
19 1/16”
SCREW
HOOD DIVIDER
LEFT
HOOD
SIDE
33 3/8”
(848mm)
(483mm)
C06026
Fig. 11 -- Economizer Hood Construction
48TC

9
17 1/4”
DIVIDER
BAROMETRIC
RELIEF
CLEANABLE
ALUMINUM
FILTER FILTER
HOOD
FILTER
CLIP
OUTSIDE
AIR
(438)
C06027
Fig. 12 -- Economizer Filter Installation
6. Caulk the ends of the joint between the unit top panel
and the hood top.
7. Replace the filter access panel.
Step 9 — Install Flue Hood
Flue hood is shipped screwed to the basepan beside the
burner compartment access panel. Remove from shipping
location and using screws provided, install flue hood and
screen in location shown in Fig. 13.
BLOWER
ACCESS
PANEL
C07081
Fig. 13 -- Flue Hood Details
Step 10 — Install Gas Piping
Installation of the gas piping must be accordance with
local building codes and with applicable national codes.
In U.S.A., refer to NFPA 54/ANSI Z223.1 National Fuel
Gas Code (NFGC). In Canada, installation must be
accordance with the CAN/CSA B149.1 and CAN/CSA
B149.2 installation codes for gas burning appliances.
This unit is factory equipped for use with Natural Gas fuel
at elevations up to 2000 ft (610 m) above sea level. Unit
may be field converted for operation at elevations above
2000 ft (610 m) and/or for use with liquefied petroleum
fuel. See accessory kit installation instructions regarding
these accessories.
For natural gas applications, gas pressure at unit gas
connection must not be less than 4 in. wg (996 Pa) or
greater than 13 in. wg (3240 Pa) while the unit is
operating. On 48TCFA04--A06 (high--heat) units, the gas
pressure at unit gas connection must not be less than 5 in.
wg (1245 Pa) or greater than 13 in. wg (3240 Pa) while
the unit is operating. For liquified petroleum applications,
the gas pressure must not be less than 11 in. wg (2740 Pa)
or greater than 13.6 in. wg (3390 Pa) at the unit
connection.
The gas supply pipe enters the unit at the burner access
panel on the front side of the unit, through the long slot at
the bottom of the access panel. The gas connection to the
unit is made to the 1/2--in. FPT gas inlet port on the unit
gas valve
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in damage
to equipment.
When connecting the gas line to the unit gas valve,
the installer MUST use a backup wrench to prevent
damage to the valve.
CAUTION
!
Install a gas supply line that runs to the unit heating
section. Refer to the NFPA 54/NFGC or equivalent code
for gas pipe sizing data. Do not use a pipe size smaller
than 1/2--in. Size the gas supply line to allow for a
maximum pressure drop of 0.5--in wg (124 Pa) between
gas regulator source and unit gas valve connection when
unit is operating at high--fire flow rate.
The gas supply line can approach the unit in three ways:
horizontally from outside the unit (across the roof),
thru--curb/under unit basepan (accessory kit required) or
through unit basepan (factory--option or accessory kit
required). Consult accessory kit installation instructions
for details on these installation methods.
Factory--Option Thru--Base Connections —
This service connection kit consists of a 1/2--in NPT gas
adapter fitting (brass), a 1/2--in electrical bulkhead
connector and a 3/4--in electrical bulkhead connector, all
factory--installed in the embossed (raised) section of the
unit basepan in the condenser section.
LOW VOLTAGE
CONDUIT
CONNECTOR
BRASS FITTING FOR 3 TO 6 TON UNITS.
STAINLESS STEEL FITTING FOR 7 1/2 TO 12 1/2 TON.
HIGH VOLTAGE
CONDUIT
CONNECTOR
C08015
Fig. 14 -- Fittings
48TC

10
The thru--base gas connector has male and female threads.
The male threads protrude above the basepan of the unit;
the female threads protrude below the basepan.
Check tightness of connector lock nuts before connecting
gas piping.
Install a 1/2--in NPT street elbow on the thru--base gas
fitting. Attach a 1/2--in pipe nipple with minimum length
of 16--in (406 mm) (field--supplied) to the street elbow
and extend it through the access panel at the gas support
bracket. See Fig. 15.
EMBOSSMENT BRASS FITTING
FOR 3-6 TON UNITS
SUPPORT
BRACKET
C08016
Fig. 15 -- Gas Line Piping for 3 to 6 Ton Units Only
Other hardware required to complete the installation of
the gas supply line will include a manual shutoff valve, a
sediment trap (drip leg) and a ground--joint union. A
pressure regulator valve may also be required (to convert
gas pressure from pounds to inches of pressure). The
manual shutoff valve must be located within 6--ft (1.83 m)
of the unit. The union, located in the final leg entering the
unit, must be located at least 9--in (230 mm) away from
the access panel to permit the panel to be removed for
service. If a regulator valve is installed, it must be located
a minimum of 4--ft (1220 mm) away from the unit’s flue
outlet. Some municipal codes require that the manual
shutoff valve be located upstream of the sediment trap.
See Figures 16 and 17 for typical piping arrangements for
gas piping that has been routed through the sidewall of the
curb. See Fig. 18 for typical piping arrangement when
thru--base is used. Ensure that all piping does not block
access to the unit’s main control box or limit the required
working space in front of the control box.
9” (229mm) min
Union
Shut Off
Valve
Drip
Leg
Thru-Curb Adapter
Unit Base Rail
C07469
Fig. 16 -- Gas Piping
Drip
Leg
Shut Off
Valve
Union
Thru-Curb Adapter
Burner
Access
Panel
9” (229mm) min
Unit Base Rail
C07470
Fig. 17 -- Gas Piping
C08018
Fig. 18 -- Gas Piping Thru--Base Connections
48TC

11
When installing the gas supply line, observe local codes
pertaining to gas pipe installations. Refer to the NFPA
54/ANSI Z223.1 NFGC latest edition (in Canada,
CAN/CSA B149.1). In the absence of local building
codes, adhere to the following pertinent
recommendations:
1. Avoid low spots in long runs of pipe. Grade all pipe
1/4--in. in every 15 ft (7 mm in every 5 m) to prevent
traps. Grade all horizontal runs downward to risers.
Use risers to connect to heating section and to meter.
2. Protect all segments of piping system against physical
and thermal damage. Support all piping with appro-
priate straps, hangers, etc. Use a minimum of one
hanger every 6 ft (1.8 m). For pipe sizes larger than
1/2--in., follow recommendations of national codes.
3. Apply joint compound (pipe dope) sparingly and only
to male threads of joint when making pipe connec-
tions. Use only pipe dope that is resistant to action of
liquefied petroleum gases as specified by local and/or
national codes. If using PTFE (Teflon) tape, ensure
the material is Double Density type and is labeled for
use on gas lines. Apply tape per manufacturer’s in-
structions.
4. Pressure--test all gas piping in accordance with local
and national plumbing and gas codes before connect-
ing piping to unit.
NOTE: Pressure test the gas supply system after the gas
supply piping is connected to the gas valve. The supply
piping must be disconnected from the gas valve during the
testing of the piping systems when test pressure is in
excess of 0.5 psig (3450 Pa). Pressure test the gas supply
piping system at pressures equal to or less than 0.5 psig
(3450 Pa). The unit heating section must be isolated from
the gas piping system by closing the external main manual
shutoff valve and slightly opening the ground--joint union.
Check for gas leaks at the field--installed and
factory--installed gas lines after all piping connections
have been completed. Use soap--and--water solution (or
method specified by local codes and/or regulations).
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
SConnect gas pipe to unit using a backup wrench to
avoid damaging gas controls.
SNever purge a gas line into a combustion chamber.
SNever test for gas leaks with an open flame. Use a
commercially available soap solution made
specifically for the detection of leaks to check all
connections.
SUse proper length of pipe to avoid stress on gas
control manifold.
!WARNING
Step 11 — Install External Condensate Trap and
Line
The unit has one 3/4-in. condensate drain connection on
the end of the condensate pan and an alternate connection
on the bottom. See Fig. 19. Unit airflow configuration
does not determine which drain connection to use. Either
drain connection can be used with vertical or horizontal
applications.
When using the standard side drain connection, ensure the
red plug in the alternate bottom connection is tight. Do
this before setting the unit in place. The red drain pan can
be tightened with a 1/2--in. square socket drive extension.
To use the alternate bottom drain connection, remove the
red drain plug from the bottom connection (use a 1/2--in.
square socket drive extension) and install it in the side
drain connection.
DRAIN
(FACTORY-INSTALLED)
PLUG
CONDENSATE PAN (SIDE VIEW)
STANDARD
SIDE DRAIN
ALTERNATE
BOTTOM DRAIN
C08021
Fig. 19 -- Condensate Drain Pan (Side View)
The piping for the condensate drain and external trap can
be completed after the unit is in place. See Fig. 20.
NOTE: Trap should be deep enough to offset maximum unit static
difference. A 4” (102) trap is recommended.
MINIMUM PITCH
1” (25mm) PER
10’ (3m) OF LINE
BASE RAIL
OPEN
VENT
TO ROOF
DRAIN
DRAIN PLUG
ROOF
CURB
SEE NOTE
2˝(51) MIN
C08022
Fig. 20 -- Condensate Drain Piping Details
All units must have an external trap for condensate
drainage. Install a trap at least 4-in. (102 mm) deep and
protect against freeze-up. If drain line is installed
downstream from the external trap, pitch the line away
from the unit at 1-in. per 10 ft (25 mm in 3 m) of run. Do
48TC

12
not use a pipe size smaller than the unit connection
(3/4-in.).
Step 12 — Make Electrical Connections
ELECTRICAL 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 NEC (National Electrical Code);
ANSI/NFPA 70, latest edition (in Canada, Canadian
Electrical Code CSA [Canadian Standards
Association] C22.1), and local electrical codes.
!WARNING
Field Power Supply —
If equipped with optional Powered Convenience Outlet:
The power source leads to the convenience outlet’s
transformer primary are not factory connected. Installer
must connect these leads according to required operation
of the convenience outlet. If an always--energized
convenience outlet operation is desired, connect the
source leads to the line side of the unit--mounted
disconnect. (Check with local codes to ensure this method
is acceptable in your area.) If a de--energize via unit
disconnect switch operation of the convenience outlet is
desired, connect the source leads to the load side of the
unit disconnect. On a unit without a unit--mounted
disconnect, connect the source leads to compressor
contactor C and indoor fan contactor IFC pressure lugs
with unit field power leads.
All units except 208/230-v units are factory wired for the
voltage shown on the nameplate. If the 208/230-v unit is
to be connected to a 208-v power supply, the control
transformer must be rewired by moving the black wire
with the 1/4-in. female spade connector from the 230--v
connection and moving it to the 200-v 1/4-in. male
terminal on the primary side of the transformer. Refer to
unit label diagram for additional information. Field power
wires will be connected line--side pressure lugs on the
power terminal block or at factory--installed option
non--fused disconnect.
Field power wires are connected to the unit at line--side
pressure lugs on compressor contactor C and indoor fan
contactor IFC (see wiring diagram label for control box
component arrangement) or at factory--installed option
non--fused disconnect switch. Max wire size is #2 AWG
(copper only).
NOTE: TEST LEADS -- Unit may be equipped with
short leads (pigtails) on the field line connection points on
contactor C or optional disconnect switch. These leads are
for factory run--test purposes only; remove and discard
before connecting field power wires to unit connection
points. Make field power connections directly to line
connection pressure lugs only.
Units Without Factory--Installed Disconnect —
When installing units, provide a disconnect switch per
NEC (National Electrical Code) of adequate size.
Disconnect sizing data is provided on the unit informative
plate. Locate on unit cabinet or within sight of the unit per
national or local codes. Do not cover unit informative
plate if mounting the disconnect on the unit cabinet.
Units with Factory--Installed Disconnect —
The factory--installed option disconnect switch is located
in a weatherproof enclosure located under the main
control box. The manual switch handle is accessible
through an opening in the access panel.
All units --
All field wiring must comply with NEC and all local
codes. Size wire based on MCA (Minimum Circuit Amps)
on the unit informative plate. See Fig. 21 for power wiring
connections to the unit power terminal block and
equipment ground. Maximum wire size is #2 ga AWG per
pole.
Provide a ground--fault and short--circuit over--current
protection device (fuse or breaker) per NEC Article 440
(or local codes). Refer to unit informative data plate for
MOCP (Maximum Over--current Protection) device size.
Disconnect
per
NEC
Disconnect
per
NEC
208/230-1-60
11 13 11 13 13
L1 L2 L3
TB
CC IFC or
(1-ph
IFM)
208/230-3-60
460-3-60
375-3-60
575-3-60
Units Without Disconnect Option
Units With Disconnect Option
2
4
6
1
3
5
L1
L2
L3
Optional
Disconnect
Switch
Disconnect factory test leads; discard.
Factory
Wiring
C07494
Fig. 21 -- Power Wiring Connections
All field wiring must comply with the NEC and local
requirements.
48TC

13
Factory--Option Thru--Base Connections —
This service connection kit consists of a 1/2--in NPT gas
adapter fitting (brass), a 1/2--in electrical bulkhead
connector and a 3/4--in electrical bulkhead connector, all
factory--installed in the embossed (raised) section of the
unit basepan in the condenser section. The 3/4--in
bulkhead connector enables the low--voltage control wires
to pass through the basepan. The 1/2--in electrical
bulkhead connector allows the high--voltage power wires
to pass through the basepan. See Fig. 14.
Check tightness of connector lock nuts before connecting
electrical conduits.
Field--supplied and field--installed liquid tight conduit
connectors and conduit may be attached to the connectors
on the basepan. Pull correctly rated high voltage and low
voltage through appropriate conduits. Connect the power
conduit to the internal disconnect (if unit is so equipped)
or to the external disconnect (through unit side panel). A
hole must be field cut in the main control box bottom on
the left side so the 24--v control connections can be made.
Connect the control power conduit to the unit control box
at this hole.
Units without Thru--Base Connections —
1. Install power wiring conduit through side panel open-
ings. Install conduit between disconnect and control
box.
2. Install power lines to terminal connections as shown
in Fig. 21.
Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate. See
Table 2. On 3--phase units, voltages between phases must
be balanced within 2% and the current within 10%. Use
the formula shown in the legend for Table 2, Note 2 to
determine the percent of voltage imbalance. Operation on
improper line voltage or excessive phase imbalance
constitutes abuse and may cause damage to electrical
components. Such operation would invalidate any
applicable Carrier warranty.
Field Control Wiring —
The 48TC unit requires an external temperature control
device. This device can be a thermostat (field--supplied)
or a PremierLink controller (available as factory--installed
option or as field--installed accessory, for use on a Carrier
Comfort Network or as a stand alone control) or a Local
Equipment Interface (LEI) card that will communicate
with a Building Management System using non--CCN
protocols (LEI card also available as factory--installed
option or as field--installed accessory).
Thermostat —
Install a Carrier--approved accessory thermostat according
to installation instructions included with the accessory.
For complete economizer function, select a two--stage
cooling thermostat. Locate the thermostat accessory on a
solid wall in the conditioned space to sense average
temperature in accordance with the thermostat installation
instructions.
If the thermostat contains a logic circuit requiring 24--v
power, use a thermostat cable or equivalent single leads of
different colors with minimum of seven leads. If the
thermostat does not require a 24--v source (no “C”
connection required), use a thermostat cable or equivalent
with minimum of six leads. Check the thermostat
installation instructions for additional features which
might require additional conductors in the cable.
For wire runs up to 50 ft. (15 m), use no. 18 AWG
(American Wire Gage) insulated wire (35--deg C
minimum). For 50 to 75 ft. (15 to 23 m), use no. 16 AWG
insulated wire (35--deg C minimum). For over 75 ft. (23
m), use no. 14 AWG insulated wire (35--deg C minimum).
All wire sizes larger than no. 18 AWG cannot be directly
connected to the thermostat and will require a junction
box and splice at the thermostat.
WIRE
CONNECTIONS
TO
LOW-VOLTAGE
SECTION
COOL STAGE 1
FA N
HEAT STAGE 1
COOL STAGE 2
HEAT STAGE 2
24 VAC HOT
24 VAC COM
N/A
OUTDOOR AIR
SENSOR
Y1/W2
G
W/W1
Y/Y2
O/W2
R
C
S1
S2
THERMOSTAT DIPSWITCH SETTINGS
R
G
Y1
Y2
W1
W2
C
IFO/X
ON
OFF
ABCD
LEGEND
NOTE: Underlined letter indicates active thermostat output when
configured for A/C operation.
Field Wiring
C07102
Fig. 22 -- Low--Voltage Connections
Unit without thru--base connection kit —
Pass the thermostat control wires through the hole
provided in the corner post; then feed the wires through
the raceway built into the corner post to the control box.
48TC

14
Pull the wires over to the terminal strip on the upper--left
corner of the Controls Connection Board. See Fig. 23.
RACEWAY
HOLE IN END PANEL (HIDDEN)
C08027
Fig. 23 -- Field Control Wiring Raceway
NOTE: If thru--the--bottom connections accessory is
used, refer to the accessory installation instructions for
information on routing power and control wiring.
Heat Anticipator Settings —
Set heat anticipator settings at 0.14 amp for the first stage
and 0.14 amp for second--stage heating, when available.
PremierLink (Factory--Option) —
The PremierLink CCN--interface module will be
factory--mounted in the main control box, to the left of the
Controls Connection Board. Factory--harnesses will
complete required wiring between PremierLink and unit
wiring. Field connections to the PremierLink control will
be made at a supplemental terminal strip located in the
unit main box below the PremierLink board. (Additional
details on installation of the PremierLink were
unavailable at the time of the printing of this manual.
Contact your Carrier distributor for latest information.)
TB - 1
R
Y1
Y2
W1
W2
G
C
X
1
2
3
4
5
6
7
8
TB - 3
1
2
3
4
5
6
7
8
TB - 2
1
2
3
4
5
6
7
8
J6
ANAL OG
J5
0 - 20 mA IN
J4
DISCRETE
J1
PWR
J2
COMMS
J9
0-20 mA
J8
Relays
HK50AA039
BRN
BRN WHT
WHT
RED
PNK
PNK
ORNORN
ORN
ORN
GRA
GRA
ORN
RED
J7
PP/MP
WHT
BLK
RED
RED
PNK
WHT
BLK
PNK
WHT
BLU
ORN
YEL
GRN
BRN
BRN
RED
RED
BRN
BRN
BLK
BLK
BRN
BRN
BLU
BLU
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
PNK
PNK
VIO
VIO
PNK
PNK
GRA
GRA
GRA
SAT
BRN
ORN
BLK
RED
Space Temp./ Set
Point Adjustment
Indoor Air
Quality Sensor
OAT
PNK
VIO
YEL
YEL
BLU
BLU
Economi$er2
4 - 20mA
BLK
RED
WHT
PremierLink
GRN
YEL
BLU
BLU
BLU
Outdoor Air
Quality Sensor
Power Exhaust/Energy Recycler
CCN
Comm.
RMTOCC
SFS
CMPSAFE
FSD
RTU Terminal
Board
TR TR1
SR
23
+
+
S
RED
BLK
RED
GRAY
GRAY
OUTDOOR AIR
ENTHALPY SENSOR
RETURN AIR
ENTHALPY
SENSOR
B1
BLK
C07073
Fig. 24 -- Typical PremierLink Controls Wiring
48TC

15
Table 2 – Unit Wire/MOCP Sizing Data
UNIT
NOM.
V --- P h --- H z
IFM
TYPE
COMBUSTION
FAN MOTOR
FLA
POWER
EXHAUST
FLA
NO C.O. or UNPWRD C.O.
NO P.E. w/ P.E. (pwrd fr/ unit)
MCA MOCP DISC. SIZE MCA MOCP DISC. SIZE
FLA LRA FLA LRA
48TC**04
208/230---1--- 60 STD 0.48 1.9 27.6 40.0 27 97 29.5 45.0 29 99
MED 27.6 40.0 27 97 29.5 45.0 29 99
208/230---3--- 60
STD
0.48 1.9
19.9 30.0 20 91 21.8 30.0 22 93
MED 19.9 30.0 20 91 21.8 30.0 22 93
HIGH 20.2 30.0 20 109 22.1 30.0 22 111
4 6 0 --- 3 --- 6 0
STD
0.25 1.0
10.4 15.0 10 47 11.4 15.0 11 48
MED 10.4 15.0 10 47 11.4 15.0 11 48
HIGH 10.9 15.0 11 56 11.9 15.0 12 57
5 7 5 --- 3 --- 6 0
STD
0.24 1.9
7.5 15.0 845 9.4 15.0 10 47
MED 7.5 15.0 845 9.4 15.0 10 47
HIGH 7.6 15.0 851 9.5 15.0 10 53
48TC**05
208/230---1--- 60 STD 0.48 1.9 34.1 50.0 33 135 36.0 50.0 35 137
MED 34.1 50.0 33 135 36.0 50.0 35 137
208/230---3--- 60
STD
0.48 1.9
24.0 30.0 24 101 25.9 30.0 26 103
MED 24.0 30.0 24 101 25.9 30.0 26 103
HIGH 24.3 30.0 24 119 26.2 30.0 26 121
4 6 0 --- 3 --- 6 0
STD
0.25 1.0
10.9 15.0 11 50 11.9 15.0 12 51
MED 10.9 15.0 11 50 11.9 15.0 12 51
HIGH 11.4 15.0 11 59 12.4 15.0 12 60
5 7 5 --- 3 --- 6 0
STD
0.24 1.9
7.5 15.0 845 9.4 15.0 10 47
MED 7.5 15.0 845 9.4 15.0 10 47
HIGH 7.6 15.0 851 9.5 15.0 10 53
1Fuse or breaker
LEGEND:
CO --- Convenient outlet
DISC --- Disconnect
FLA --- Full load amps
IFM --- Indoor fan motor
LRA --- Locked rotor amps
MCA --- Minimum circuit amps
MOCP --- Maximum over current protection
P E --- Po w e r e x h a u s t
UNPWR CO --- Unpowered convenient outlet
NOTES:
1. In compliance with NEC requirements for multimotor and
combination load equipment (refer to NEC Articles 430 and
440), the overcurrent protective device for the unit shall be
fuse or HACR breaker. Canadian units may be fuse or circuit
breaker.
2. Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply
voltage is greater than 2%. Use the following formula to de-
termine the percentage of voltage imbalance.
% Voltage Imbalance = 100 x
max voltage deviation from average voltage
average voltage
Example: Supply voltage is 230-3-60
AB = 224 v
BC = 231 v
AC = 226 v
Average Voltage =
(224 + 231 + 226)
=
681
33
= 227
Determine maximum deviation from average voltage.
(AB) 227 – 224 = 3 v
(BC) 231 – 227 = 4 v
(AC) 227 – 226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
% Voltage Imbalance = 100 x
4
227
= 1.76%
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more than
2%, contact your local electric utility company immediately.
48TC

16
Table 2 — Unit Wire/MOCP Sizing Data (cont)
UNIT
NOM.
V --- P h --- H z
IFM
TYPE
COMBUSTION
FAN MOTOR
FLA
POWER
EXHAUST
FLA
NO C.O. or UNPWRD C.O.
NO P.E. w/ P.E. (pwrd fr/ unit)
MCA MOCP DISC. SIZE MCA MOCP DISC. SIZE
FLA LRA FLA LRA
48TC**06
208/230---1--- 60 STD 0.48 1.9 39.6 60.0 38 152 41.5 60.0 40 154
MED 41.7 60.0 40 177 43.6 60.0 43 179
208/230---3--- 60
STD
0.48 1.9
26.4 40.0 26 128 28.3 40.0 28 130
MED 26.7 40.0 26 146 28.6 40.0 28 148
HIGH 29.0 40.0 29 172 30.9 45.0 31 174
4 6 0 --- 3 --- 6 0
STD
0.25 1.0
12.8 20.0 12 61 13.8 20.0 14 62
MED 13.3 20.0 13 70 14.3 20.0 14 71
HIGH 14.1 20.0 14 83 15.1 20.0 15 84
5 7 5 --- 3 --- 6 0
STD
0.24 1.9
10.0 15.0 10 47 11.9 15.0 12 49
MED 10.9 15.0 11 64 12.8 15.0 13 66
HIGH 10.9 15.0 11 64 12.8 15.0 13 66
48TC**07
208/230---3--- 60
STD
0.48 1.9
30.9 45.0 30 159 32.8 50.0 32 161
MED 33.2 50.0 33 185 35.1 50.0 35 187
HIGH 33.2 50.0 33 185 35.1 50.0 35 187
4 6 0 --- 3 --- 6 0
STD
0.25 1.0
15.8 25.0 15 80 16.8 25.0 17 81
MED 16.6 25.0 16 93 17.6 25.0 17 94
HIGH 17.6 25.0 17 102 18.6 25.0 19 103
5 7 5 --- 3 --- 6 0
STD
0.24 1.9
12.1 15.0 12 64 14.0 20.0 14 66
MED 12.9 20.0 13 75 14.8 20.0 15 77
HIGH 12.9 20.0 13 75 14.8 20.0 15 77
1Fuse or breaker
LEGEND:
CO --- Convenient outlet
DISC --- Disconnect
FLA --- Full load amps
IFM --- Indoor fan motor
LRA --- Locked rotor amps
MCA --- Minimum circuit amps
MOCP --- Maximum over current protection
P E --- Po w e r e x h a u s t
UNPWR CO --- Unpowered convenient outlet
NOTES:
1. In compliance with NEC requirements for multimotor and
combination load equipment (refer to NEC Articles 430 and
440), the overcurrent protective device for the unit shall be
fuse or HACR breaker. Canadian units may be fuse or circuit
breaker.
2. Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply
voltage is greater than 2%. Use the following formula to de-
termine the percentage of voltage imbalance.
% Voltage Imbalance = 100 x
max voltage deviation from average voltage
average voltage
Example: Supply voltage is 230-3-60
AB = 224 v
BC = 231 v
AC = 226 v
Average Voltage =
(224 + 231 + 226)
=
681
33
= 227
Determine maximum deviation from average voltage.
(AB) 227 – 224 = 3 v
(BC) 231 – 227 = 4 v
(AC) 227 – 226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
% Voltage Imbalance = 100 x
4
227
= 1.76%
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more than
2%, contact your local electric utility company immediately.
48TC

17
Table 2 — Unit Wire/MOCP Sizing Data (cont)
UNIT
NOM.
V --- P h --- H z
IFM
TYPE
COMBUSTION
FAN MOTOR
FLA
POWER
EXHAUST
FLA
w/ PWRD C.O.
NO P.E. w/ P.E. (pwrd fr/ unit)
MCA MOCP DISC. SIZE MCA MOCP DISC. SIZE
FLA LRA FLA LRA
48TC**04
208/230---1--- 60 STD 0.48 1.9 32.4 45.0 33 102 34.3 50.0 35 104
MED 32.4 45.0 33 102 34.3 50.0 35 104
208/230---3--- 60
STD
0.48 1.9
24.7 30.0 25 96 26.6 30.0 28 98
MED 24.7 30.0 25 96 26.6 30.0 28 98
HIGH 25.0 30.0 26 114 26.9 30.0 28 116
4 6 0 --- 3 --- 6 0
STD
0.25 1.0
12.6 15.0 13 49 13.6 20.0 14 50
MED 12.6 15.0 13 49 13.6 20.0 14 50
HIGH 13.1 15.0 13 58 14.1 20.0 15 59
5 7 5 --- 3 --- 6 0
STD
0.24 1.9
9.2 15.0 947 11.1 15.0 12 49
MED 9.2 15.0 947 11.1 15.0 12 49
HIGH 9.3 15.0 10 53 11.2 15.0 12 55
48TC**05
208/230---1--- 60 STD 0.48 1.9 38.9 60.0 39 140 40.8 60.0 41 142
MED 38.9 60.0 39 140 40.8 60.0 41 142
208/230---3--- 60
STD
0.48 1.9
28.8 40.0 29 106 30.7 40.0 31 108
MED 28.8 40.0 29 106 30.7 40.0 31 108
HIGH 29.1 40.0 30 124 31.0 40.0 32 126
4 6 0 --- 3 --- 6 0
STD
0.25 1.0
13.1 15.0 13 52 14.1 20.0 14 53
MED 13.1 15.0 13 52 14.1 20.0 14 53
HIGH 13.6 20.0 14 61 14.6 20.0 15 62
5 7 5 --- 3 --- 6 0
STD
0.24 1.9
9.2 15.0 947 11.1 15.0 12 49
MED 9.2 15.0 947 11.1 15.0 12 49
HIGH 9.3 15.0 10 53 11.2 15.0 12 55
1Fuse or breaker
LEGEND:
CO --- Convenient outlet
DISC --- Disconnect
FLA --- Full load amps
IFM --- Indoor fan motor
LRA --- Locked rotor amps
MCA --- Minimum circuit amps
MOCP --- Maximum over current protection
P E --- Po w e r e x h a u s t
UNPWR CO --- Unpowered convenient outlet
NOTES:
1. In compliance with NEC requirements for multimotor and
combination load equipment (refer to NEC Articles 430 and
440), the overcurrent protective device for the unit shall be
fuse or HACR breaker. Canadian units may be fuse or circuit
breaker.
2. Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply
voltage is greater than 2%. Use the following formula to de-
termine the percentage of voltage imbalance.
% Voltage Imbalance = 100 x
max voltage deviation from average voltage
average voltage
Example: Supply voltage is 230-3-60
AB = 224 v
BC = 231 v
AC = 226 v
Average Voltage =
(224 + 231 + 226)
=
681
33
= 227
Determine maximum deviation from average voltage.
(AB) 227 – 224 = 3 v
(BC) 231 – 227 = 4 v
(AC) 227 – 226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
% Voltage Imbalance = 100 x
4
227
= 1.76%
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more than
2%, contact your local electric utility company immediately.
48TC

18
Table 2 — Unit Wire/MOCP Sizing Data (cont)
UNIT
NOM.
V --- P h --- H z
IFM
TYPE
COMBUSTION
FAN MOTOR
FLA
POWER
EXHAUST
FLA
w/ PWRD C.O.
NO P.E. w/ P.E. (pwrd fr/ unit)
MCA MOCP DISC. SIZE MCA MOCP DISC. SIZE
FLA LRA FLA LRA
48TC**06
208/230---1--- 60 STD 0.48 1.9 44.4 60.0 44 157 46.3 60.0 46 159
MED 46.5 60.0 46 182 48.4 60.0 48 184
208/230---3--- 60
STD
0.48 1.9
31.2 45.0 31 133 33.1 45.0 34 135
MED 31.5 45.0 32 151 33.4 45.0 34 153
HIGH 33.8 45.0 34 177 35.7 50.0 37 179
4 6 0 --- 3 --- 6 0
STD
0.25 1.0
15.0 20.0 15 63 16.0 20.0 16 64
MED 15.5 20.0 16 72 16.5 20.0 17 73
HIGH 16.3 20.0 17 85 17.3 20.0 18 86
5 7 5 --- 3 --- 6 0
STD
0.24 1.9
11.7 15.0 12 49 13.6 20.0 14 51
MED 12.6 15.0 13 66 14.5 20.0 15 68
HIGH 12.6 15.0 13 66 14.5 20.0 15 68
48TC**07
208/230---3--- 60
STD
0.48 1.9
35.7 50.0 36 164 37.6 50.0 38 166
MED 38.0 50.0 38 190 39.9 50.0 40 192
HIGH 38.0 50.0 38 190 39.9 50.0 40 192
4 6 0 --- 3 --- 6 0
STD
0.25 1.0
18.0 25.0 18 82 19.0 25.0 19 83
MED 18.8 25.0 19 95 19.8 25.0 20 96
HIGH 19.8 25.0 20 104 20.8 30.0 21 105
5 7 5 --- 3 --- 6 0
STD
0.24 1.9
13.8 20.0 14 66 15.7 20.0 16 68
MED 14.6 20.0 15 77 16.5 20.0 17 79
HIGH 14.6 20.0 15 77 16.5 20.0 17 79
1Fuse or breaker
LEGEND:
CO --- Convenient outlet
DISC --- Disconnect
FLA --- Full load amps
IFM --- Indoor fan motor
LRA --- Locked rotor amps
MCA --- Minimum circuit amps
MOCP --- Maximum over current protection
P E --- Po w e r e x h a u s t
UNPWR CO --- Unpowered convenient outlet
NOTES:
1. In compliance with NEC requirements for multimotor and
combination load equipment (refer to NEC Articles 430 and
440), the overcurrent protective device for the unit shall be
fuse or HACR breaker. Canadian units may be fuse or circuit
breaker.
2. Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply
voltage is greater than 2%. Use the following formula to de-
termine the percentage of voltage imbalance.
% Voltage Imbalance = 100 x
max voltage deviation from average voltage
average voltage
Example: Supply voltage is 230-3-60
AB = 224 v
BC = 231 v
AC = 226 v
Average Voltage =
(224 + 231 + 226)
=
681
33
= 227
Determine maximum deviation from average voltage.
(AB) 227 – 224 = 3 v
(BC) 231 – 227 = 4 v
(AC) 227 – 226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
% Voltage Imbalance = 100 x
4
227
= 1.76%
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more than
2%, contact your local electric utility company immediately.
48TC

19
C08019
Fig. 25 -- EconoMi$er IV Wiring
Step 13 — Adjust Factory--Installed Options
Smoke Detectors —
Smoke detector(s) will be connected at the Controls
Connections Board, at terminals marked “Smoke
Shutdown”. Remove jumper JMP 3 when ready to
energize unit.
EconoMi$er IV Occupancy Switch —
Refer to Fig. 25 for general EconoMi$er IV wiring.
External occupancy control is managed through a
connection on the Controls Connections Board.
If external occupancy control is desired, connect a time
clock or remotely controlled switch (closed for Occupied,
open for Unoccupied sequence) at terminals marked
OCCUPANCY. Remove or cut jumper JMP 2 to complete
the installation.
Step 14 — Install Accessories
Available accessories include:
Curb
Thru--base connection kit (must be installed before unit
is set on curb)
LP conversion kit
Manual outside air damper
Two--Position motorized outside air damper
EconoMi$er IV (with control)
EconoMi$er2 (without control/for external signal)
Barometric relief
Power Exhaust
Differential dry--bulb sensor (EconoMi$er IV)
Outdoor enthalpy sensor
Differential enthalpy sensor
CO2 sensor
Smoke detector (Return Air and/or Supply Air)
DDC interface (PremierLink)
4--Inch filter tracks
Louvered hail guard
Hood--type hail guard
UV--C lamp kit
Phase monitor control
Refer to separate installation instructions for information
on installing these accessories.
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20
Copyright 2008 Carrier Corp. D7310 W. Morris St. DIndianapolis, IN 46231 Printed in U.S.A. Edition Date: 01/08
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Catalog No:48TC---1SI
Replaces: NEW
48TC