L1s- Condensing Units

What is a condensing unit?

The outdoor portion of many split DX refrigeration systems. It normally contains the compressor, condenser coil, condenser fan(s), and controls.

What does it do?

It receives hot refrigerant vapor from the indoor evaporator system, rejects heat outdoors, and returns high-pressure liquid refrigerant toward the expansion device.

What normally connects a condensing unit to an indoor unit?

Refrigerant piping - typically a liquid line and suction line.

What should be commissioned?

Compressor operation, fan operation/rotation, staging, refrigerant conditions, safeties, electrical connections, vibration, alarms, and response to cooling demand.

Common problems?

Low/high refrigerant pressure, refrigerant leaks, dirty condenser coils, failed fans, compressor faults, incorrect refrigerant charge, and control wiring problems.