Carrier 38BYW Installation And Start-Up Instructions Manual Download Page 4

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3. Connect refrigerant tubing to fittings on outdoor unit vapor

and liquid service valves.

4. Service valves are closed from factory and ready for brazing.

5. After wrapping service valve with a wet cloth, tubing set can

be brazed to service valve using either silver bearing or
non-silver bearing brazing material.

6. Refrigerant tubing and indoor coil are now ready for leak

testing. This check should include all field and factory joints.

Step 10—Make Electrical Connections

To avoid personal injury or death, do not supply power to unit
with compressor terminal box cover removed.

Be sure field wiring complies with local and national fire, safety,
and electrical codes, and voltage to system is within limits shown
on unit rating plate. Contact local power company for correction of
improper voltage. See unit rating plate for recommended circuit
protection device.

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.

NOTE:

Use copper wire only between disconnect switch and

unit.

NOTE:

Install branch circuit disconnect per NEC of adequate

size to handle unit starting current. Locate disconnect within sight
from and readily accessible from unit, per Section 440-14 of NEC.

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.

The unit cabinet must have an uninterrupted or unbroken
ground to minimize personal injury if an electrical fault
should occur. The ground may consist of electrical wire or
metal conduit when installed in accordance with existing
electrical codes. Failure to follow this warning can result in an
electric shock, fire, or death.

CONNECT GROUND AND POWER WIRES — Connect ground
wire to ground connection in control box for safety. Connect
power wiring to contactor as shown in Fig. 9.

CONNECT CONTROL WIRING — Route 24-v control wires
through control wiring grommet and connect leads to control
wiring. (See Fig. 9.)

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.

Use furnace transformer, fan coil transformer, or accessory trans-
former for control power, 24-v/40-va minimum.

NOTE:

Use of available 24-v accessories may exceed the mini-

mum 40-va power requirement. Determine total transformer load-
ing and increase the transformer capacity or split the load with an
accessory transformer as required.

NOTE:

The defrost timer is factory set for 90-minute cycles. The

timer can be field set for 30- and 50-minute cycles depending on
defrost conditions in your geographical location.

Step 11—Compressor Crankcase Heater

When equipped with a crankcase heater, energize heater a mini-
mum of 24 hr before starting unit. To energize heater only, set
thermostat to OFF and close electrical disconnect to outdoor unit.

A crankcase heater is required if refrigerant tubing is longer than
50 ft.

NOTE:

The Seasonal Energy Efficiency Ratio (SEER) and Heat-

ing Seasonal Performance Factor (HSPF) is obtained with the
crankcase heater de-energized. To de-energize the crankcase
heater, disconnect black crankcase heater wires at contactor. After
disconnecting, make sure wires are isolated from all other electri-
cal connections and components to prevent electrical shorting.

Step 12—Install Electrical Accessories

Refer to the individual instructions packaged with kits or acces-
sories when installing.

Fig. 8—Liquid Service Valve

A98048

PISTON BODY

PISTON

PISTON
RETAINER

SWEAT/FLARE
ADAPTER

Fig. 9—Line Power Connections

A94025

DISCONNECT
PER N.E.C. AND/OR
LOCAL CODES

CONTACTOR