Carrier Split Systems and Condensers 38AP

WARNING: Do not supply power to unit with compressor cover removed. Failure to follow this warning can cause a fire, resulting in personal injury or death.

WARNING: Exercise extreme caution when reading compressor currents when high-voltage power is on. Correct any of the problems described below before installing and running a replacement compressor. Wear safety glasses and gloves when handling refrigerants. Failure to follow this warning can cause fire, resulting in personal injury or death.

CAUTION: Do not manually operate contactors. Serious damage to the machine may result.

Proper voltage to the unit should be verified.

The normal checks of motor winding continuity and short to ground should be made to determine if the inherent overload motor protector has opened or if an internal motor short or ground fault has developed. If the protector has opened, the compressor must be allowed to cool sufficiently to allow it to reset.

Proper indoor and outdoor blower/fan operation should be verified.

With service gages connected to suction and discharge pressure fittings, turn on the compressor. If suction pressure falls below normal levels, the system is either low on charge or there is a flow blockage in the system.

If suction pressure does not drop and discharge pressure does not rise to normal levels, reverse any two of the compressor power leads and reapply power to make sure compressor was not wired to run in reverse direction. If pressures still do not move to normal values, the compressor may be faulty. Reconnect the compressor leads as originally configured.

To test if the compressor is pumping properly, the compressor current draw must be compared to published compressor performance curves using the operating pressures and voltage of the system. If the measured average current deviates more than ±15% from published values, a faulty compressor may be indicated. A current imbalance exceeding 15% of the average on the three phases should be investigated further.

Select the type of condenser fan

If Propeller (Metal) Fan and AeroAcoustic Fan with Gray Bolt is selected, apply Tectyl 506G (Ashland Petroleum Company) grease to the fan shaft and hub.

AeroAcoustic Fan with Black Bolt

This assembly uses Loctite 680 Retaining Compound. DO NOT lubricate the fan shaft or fan hub.

The condenser fan motors have sealed bearings so no field lubrication is required.

All door hinges should be lubricated at least once a year.

Warning: This procedure requires trained personnel with PPE!

Is the new S1-S2 thermistor wiring harness fully inserted on the three pins in the correct orientation?

Is DIP switch no. 1 ON (up position) and all other DIP switches OFF (down position)?

Is the CoreSense module installed in the compressor terminal box with the tabs holding the module in place?

Is the thermistor wire harness routed as shown and plugged into the 2x2 socket on the CoreSense module?

Are the previously labeled M1, M2, T1, and T2 wires connected to the appropriate terminals on the CoreSense module?

Are the L1, L2, and L3 phase sensing wires connected to the L1, L2, and L3 compressor terminal block connections?

Are all connections secure and the compressor terminal cover installed?

Sign off on the CoreSense Communications Module Replacement

Check all system components for proper operation, including the air-handling equipment.

Check if all field-installed accessories are properly installed and wired correctly.

Open liquid line and suction line service valves.

Check tightness of all electrical connections.

Oil level in the compressor sight glasses. An acceptable oil level in the compressor is from 1/8 to 3/8 of sight glass.

Check if electrical power source agrees with unit nameplate.

Check if crankcase heaters are firmly attached to compressors, and must be on for 24 hours prior to start-up.

Check if all condenser fans are 3-phase.

For non Greenspeed units, check for proper rotation of condenser fans first BEFORE attempting to start compressors.

WARNING: Electrical shock can cause personal injury and death. Shut off all power to this equipment during installation and service.

All power disconnected and tagged?

Junction box cover removed and compressor power and ground connections disconnected?

Crankcase heater disconnected and removed from the compressor?

Motor protection module disconnected?

Cable removed from the compressor junction box?

Digital unloader solenoid removed (if applicable)?

Circuit isolated and refrigerant removed?

High pressure switch, discharge temperature thermistor, return gas thermistor, discharge pressure transducer, or suction pressure transducer removed (if applicable)?