48TC

Compressor

Lubrication

The compressor is charged with the correct amount of oil at the factory.

!CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may result in damage to components.

The compressor is in a PuronR refrigerant system and uses a polyolester (POE) oil. This oil is extremely hygroscopic, meaning it absorbs water readily. POE oils can absorb 15 times as much water as other oils designed for HCFC and CFC refrigerants. Avoid exposure of the oil to the atmosphere.

Replacing Compressor

The compressor used with Puron refrigerant contains a POE oil. This oil has a high affinity for moisture. Do not remove the compressor’s tube plugs until ready to insert the unit suction and discharge tube ends.

Compressor mounting bolt torque is 65-75 ft-lbs.

Compressor Rotation

On 3-phase units with scroll compressors, it is important to be certain compressor is rotating in the proper direction. To determine whether or not compressor is rotating in the proper direction:

1.Connect service gauges to suction and discharge pres- sure fittings.

2.Energize the compressor.

3.The suction pressure should drop and the discharge pressure should rise, as is normal on any start-up.

NOTE: If the suction pressure does not drop and the discharge pressure does not rise to normal levels:

4.Note that the evaporator fan is probably also rotating in the wrong direction.

5.Turn off power to the unit.

6.Reverse any two of the unit power leads.

7.Reapply power to the compressor.

The suction and discharge pressure levels should now move to their normal start-up levels.

NOTE: When the compressor is rotating in the wrong direction, the unit makes an elevated level of noise and does not provide cooling.

Filter Drier

Replace whenever refrigerant system is exposed to atmosphere. Only use factory specified liquid-line filter driers with working pressures no less than 650 psig. Do not install a suction-line filter drier in liquid line. A liquid-line filter drier designed for use with Puron refrigerant is required on every unit.

Condenser-Fan Adjustment

1. Shut off unit power supply. Install lockout tag.

2.Remove condenser-fan assembly (grille, motor, and fan).

3.Loosen fan hub setscrews.

4.Adjust fan height as shown in Fig. 13.

5.Tighten setscrews.

6.Replace condenser-fan assembly.

Conduit

0.14 in + 0.0 / -0.03

C08448

Fig. 13 - Condenser Fan Adjustment

Troubleshooting Cooling System

Refer to Table 1 for additional troubleshooting topics.

CONVENIENCE OUTLETS

!WARNING

ELECTRICAL OPERATION HAZARD

Failure to follow this warning could result in personal injury or death.

Units with convenience outlet circuits may use multiple disconnects. Check convenience outlet for power status before opening unit for service. Locate its disconnect switch, if appropriate, and open it. Tag-out this switch, if necessary.

Two types of convenience outlets are offered on 48TC models: Non-powered and unit-powered. Both types

provide a 125-volt GFCI (ground-fault circuit-interrupter) duplex receptacle rated at 15-A behind a hinged waterproof access cover, located on the end panel of the unit. See Fig. 14.

Pwd-CO Transformer

Conv Outlet

GFCI

Pwd-CO

Fuse

Switch

C08128

Fig. 14 - Convenience Outlet Location

Non-powered type: This type requires the field installation of a general-purpose 125-volt 15-A circuit powered from a source elsewhere in the building. Observe national and local codes when selecting wire size, fuse or

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Carrier 48TCA04---A12 appendix Convenience Outlets, Compressor, Filter Drier, Condenser-Fan Adjustment

48TCA04---A12 specifications

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