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HACR —
The amp rating of the HACR factory- - installed option is
based on the size, voltage, indoor motor and other
electrical options of the unit as shipped from the factory.
If field- - installed accessories are added or changed in the
field (i.e. power exhaust, etc.), the HACR may no longer
be of the proper amp rating and therefore will need to be
removed from the unit. See unit nameplate and label on
factory- - installed HACR for the amp rating of the HACR
that was shipped with the unit from the factory. See unit
nameplates for the proper fuse, HACR or maximum
over- - current protection device required on the unit with
field- - installed accessories.
Fig. 40 - - HACR Caution Label
Factory- - Option Thru- - Base Connections (Electrical
Connections) —
This service connection kit consists of a
bulkhead connector and a 1
connector, all factory- - installed in the embossed (raised)
section of the unit basepan in the condenser section. The
1
/
- - in. bulkhead connector enables the low- - voltage
2
control wires to pass through the basepan. The 1
electrical bulkhead connector allows the high- - voltage
power wires to pass through the basepan. See Fig. 15.
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
openings. Install conduit between disconnect and
control box.
2. Install power lines to terminal connections as shown
in Fig. 23.
C12105
1
/
- - in. electrical
2
1
/
- - in. electrical bulkhead
4
1
/
- - in.
4
Field Control Wiring —
The 48LC unit requires an external temperature control
device such as a thermostat (field- - supplied).
Thermostat —
Install a Carrier- - approved accessory thermostat according
to installation instructions included with the accessory.
For complete economizer function and 3 stage compressor
operation select a three- - stage cooling thermostat. 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.
Typical
Thermostat
Connections
C
W1
W2
G
Y3
(Note 3 & 4)
O/B/Y2
(Notes 2, 3 & 4)
(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. 41 - - Low- - Voltage Connections
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 larger than
no. 18 AWG cannot be directly connected to the thermostat
and will require a junction box and splice at the thermostat.
28
Integrated Staging Control
(ISC) Board or
SystemVu
TM
Controller
C
W1
T
H
W2
E
R
G
M
O
Y3
S
T
Y2
A
T
Y1
R
a48--- 9346
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