Factory- - Option Thru- - Base Connections; Units Without Thru- - Base Connections; Field Control Wiring; Thermostat - Carrier WeatherExpert 48LC Installation Instructions Manual

nameplates for the proper fuse, HACR or maximum
over- - current protection device required on the unit with
field- - installed accessories.
Fig. 38 - - HACR Caution Label
Factory- - Option Thru- - Base Connections —
All units are equipped with the ability to bring utilities
through the base.
Gas is brought up through an embossed area located in the
gas section behind the gas entrance post. Access is gained
through the gas access panel. A knock out must be
removed to accomplish this.
The electrical entrance is located in the control box area
and can be accessed through the control box access panel.
An embossed area is provided with three knock outs. High
voltage is brought through the multi knock out by
removing the appropriate size for the size of the fitting
7
required. A / - - in. knock out is provided for low voltage.
8
7
An additional / - - in. knock out is provided for a 115 volt
8
line which is used when the unit is equipped with the
non- - unit powered convenience outlet option.
All required fittings are field supplied. Install fittings
when access to both top and bottom of the base pan is
available. See electrical and gas connections for routing
and connection information.
Units Without Thru- - Base Connections —
1. Install liquid tight conduit between disconnect and
control box.
2. Pull correctly rated high voltage wires through the
conduit.
3. Install power lines to terminal connections as shown
in Fig. 33.
Field Control Wiring —
The 48LC unit requires an external temperature control
device such as a thermostat (field- - supplied).
Thermostat —
Install a Carrier- - approved accessory 3- - stage thermostat
according to installation instructions included with the
accessory. If a 3- - stage cooling thermostat is not available
use a 2- - stage cooling thermostat instead, but note that this
will limit cooling to just 2 stages. 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 eight leads. If the
thermostat does not require a 24- - v source (no "C"
connection required), use a thermostat cable or equivalent
with minimum of seven 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_C minimum).
For 50 to 75 ft (15 to 23 m), use no. 16 AWG insulated
wire (35_C minimum). For over 75 ft (23 m), use no. 14
AWG insulated wire (35_C minimum). All wire sizes
C12105 larger than no. 18 AWG cannot be directly connected to
the thermostat and will require a junction box and splice
at the thermostat.
Unit Without Thru- - Base Connection Kit —
Correctly rated low voltage wire can be routed through the
rubber grommet located on the corner post adjacent to the
control box access panel. Route wire through the grommet
and then route the wire behind the corner post utilizing the
factory provided wire ties secured to the control box. This
will insure separation of the field low voltage wire and the
high voltage circuit. Route the low voltage wire to the
Integrated Staging Control (ISC) board. See Fig. 39.
Typical

Thermostat

Connections
C
W1
W2
G
Y3
O/B/Y2
(Note 1)
Y1
R
Note 1: Typical multi-function marking. Follow manufacturer's configuration
Instructions to select Y2.
Note 2: Y2 to Y3 connection required for 2-stage cooling operation and when
integrated economizer function is desired.
Note 3: To Connect a 2-Stage Thermostat:
Y2 to Y3 connection required for 2-stage cooling operation which
provides low and high cooling states.
Note 4: SystemVu controller is default configured for 3-stage cooling and
2-stage heating thermostats; it can be configured for other thermostat types.
Field Wiring
Fig. 39 - - Typical Low- - Voltage Control Connections
35
Integrated Staging Control
(ISC) Board or
SystemVu
C
W1
W2
G
Y3
(Note 3 & 4)
Y2
(Notes 2, 3 & 4)
Y1
R
TM
Controller
T
H
E
R
M
O
S
T
A
T
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