Carrier 38C Series, Installation, Operation And Maintenance Manual

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with a wet cloth, the tubing set can be brazed to the service valve using either silver bearing or non-silver
bearing brazing material. Consult local code requirements. Refrigerant tubing and indoor coil are ready for leak
testing; this check should include all field and factory joints. NOTE: Unit is shipped with R-410A Holding factory
charge indicated on nameplate. Pass nitrogen or other inert gas through piping while brazing to prevent formation of
copper oxide.
Step 4 — Make Electrical Connections
Power Wiring — Unit is factory-wired for voltage shown on nameplate. Provide adequate, fused disconnect switch
within sight of unit, readily accessible but out of reach of children. Provision for locking the switch open (off) is
advisable to prevent power from being turned on while unit is being serviced. Disconnect switch, fuses, and field
wiring must be in compliance with NEC and applicable local codes. Use minimum 85 C wires for field power
connection. Route power wires through opening in the unit side panel and connect in unit control box. Unit must be
grounded
Route Ground And Power Wires — Remove access panel to gain access to unit wiring. Extend wires from
disconnect through power wiring hole provided and into unit control box. See Electrical Data Table and unit label
diagram for field-supplied wiring details.
Connect Ground And Power Wires — Connect ground wire to ground connection in control box for safety.
NOTE: Operation of unit on improper line voltage constitutes abuse and could affect unit reliability. See unit rating
plate. Do not install unit in system where voltage or phase imbalance (3 phase) may fluctuate above or below
permissible limits. Do not install unit in system where voltage may fluctuate above or below permissible limits. When
making electrical connections, provide clearance at unit for refrigerant piping connections.
NOTE: Use copper wires only between disconnect switch and unit.
NOTE: Install branch circuit disconnect of adequate size per NEC to handle unit starting current. Locate disconnect
within sight from and readily accessible from unit.
Connect Control Wiring — Route 24v control wires through control wiring and connect leads to control wiring. Use
No. 18 AWG color coded, insulated (35°C minimum) wire. If thermostat is located more than 100 ft from unit, as
measured along the control voltage wires, use No. 16 AWG color coded wire to avoid excessive voltage drop.
To avoid damage while brazing, service valves should be wrapped in a heat sinking material such as a wet
cloth. When Brazing tubing sets to service valves, a brazing shield must be used to prevent damage to the
painted unit surface.
Caution
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 the unit ground lug in
control compartment, or conduit approved for electrical ground when installed in accordance with NEC,
ANSI/NFPA 70 (American National Standards Institute/National Fire Protection Association), and local electrical
codes. Failure to follow this warning could result in the installer being liable for personal injury to others.
Warning
Unit failure as a result of operation on improper line voltage or excessive phase imbalance constitutes abuse and
may cause damage to electrical components. Such operation will invalidate any applicable Carrier warranty.
Caution
The unit cabinet must have an uninterrupted or unbroken ground. The ground may consist of electrical wire or
metal conduit when installed in accordance with existing electrical codes.
Warning
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