Carrier 38TXA ÐLine Power Connections, ÐRefrigerant Tubing, ÐEvacuate, ÐStart-Up

Step 7ÐRefrigerant Tubing

Connect vapor tube to fitting on outdoor unit vapor service valve and connect liquid tube to filter drier. (See Fig. 5.)

A brazing shield MUST be used when tubing sets are being brazed to the service valves to prevent damage to the painted unit surface.

Relieve pressure and recover all refrigerant before system repair or final unit disposal to avoid personal injury or death. Use all service ports and open all flow control devices, including solenoid valves.

The cabinet must have an uninterrupted or unbroken ground according to NEC, ANSI/NFPA 70-1996, or local codes to minimize personal injury if an electrical fault should occur. This may consist of electrical wire or conduit approved for electrical ground when installed in accordance with existing electrical codes. Failure to follow this warning could result in an electrical shock, fire, or death.

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

CONNECT GROUND AND POWER WIRES Ð Connect ground wire to ground connection in control box for safety. Connect power wiring to contactor as shown in Fig. 6.

To avoid valve damage while brazing, service valves must be wrapped with a heat-sinking material such as a wet cloth.

SWEAT CONNECTION Ð Use refrigerant grade tubing. Service valves are closed from factory and ready for brazing. After wrapping service valve and filter drier with wet cloth, tubing set can be brazed to service valve and filter drier using either silver bearing or non-silver bearing brazing material. Consult local code requirements. Refrigerant tubing and indoor coil are now ready for leak testing. This check should include all field and factory joints.

Step 8ÐEvacuate

Refrigerant tubes and indoor coil should be evacuated using the recommended deep vacuum method of 500 microns. The alternate triple evacuation method may be used if the procedure outlined in the Service Manual is followed. Always break a vacuum with dry nitrogen.

DISCONNECT

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

FIELD POWER

WIRING

3 PHASE ONLY

FIELD GROUND

WIRING

CONTACTOR

BLUE

GROUND

LUG

A94025

Never use the system compressor as a vacuum pump.

Step 9ÐMake Electrical Connections

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. (See Fig. 4.)

NOTE: Operation of unit on improper line voltage constitutes abuse and could affect unit reliability. See unit rating plate.

NOTE: Use only copper wire between disconnect switch and unit.

NOTE: Install branch circuit disconnect per NEC of adequate size to handle unit starting current, but not larger than maximum fuse size shown on unit rating plate. Locate disconnect within sight from and readily accessible from unit, per Section 440-14 of NEC.

ROUTE GROUND AND POWER WIRES Ð Remove access panel and control box cover to gain access to unit wiring. Extend wires from disconnect through power wiring hole provided and into unit control box. (See Fig. 4.) Size wires per NEC but not smaller than minimum wire size shown in presale literature.

Fig. 6ÐLine Power Connections

CONNECT CONTROL WIRING Ð Route 24-v control wires through control wiring grommet and connect to brown and blue pigtails supplied in unit splice box. (See Fig. 7.)

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, 24v/40va minimum.

NOTE: Use of available 24-v accessories may exceed the mini- mum 40-va power requirement. Determine total transformer load- ing and increase transformer capacity or split load with an accessory transformer as required.

Step 10ÐInstall Electrical Accessories

Refer to individual instructions packaged with kits or accessories when installing.

Step 11ÐStart-Up

1.After system is evacuated, fully back seat (open) liquid and vapor service valves. Unit is shipped with valve stem(s) front seated and caps installed.

2.Replace stem caps after system is opened to refrigerant flow (back seated). Replace caps finger tight and tighten additional 1/12 turn with wrench.

3.Close electrical disconnects to energize system.

4.Be sure thermostat set point is below indoor ambient tempera- ture. Set room thermostat at COOL and fan at ON or AUTO, as desired. Operate unit for 15 minutes. Check system refrigerant charge.

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