The Importance Of AC Compressor Oil Balancing


When making a replacement for your car’s air conditioning compressor, oil balancing is a vital step.

It’s crucial to mix the compressor oil properly using the appropriate lubricant and amount when installing a new air conditioning compressor in a car.

To ensure that the amount of oil in the air conditioning system stays the same as per the original specification, oil balancing is done.

Without oil balancing, the system is highly susceptible to liquid slugging and compressor lockup caused by too much oil, which could necessitate additional repairs.

The article discusses the importance of A/C compressor oil balancing and instructions for oil balancing.

Recovery of Refrigerant

At the moment of recovery, it is crucial that the oil evacuated from the system is measured properly. The air conditioning system will require the same amount of recovered oil to be refilled.

Old Compressor

Measure the oil after removing it from the compressor (volume). If necessary, refer to the compressor installation manual to determine the right way to drain the oil.

As a general rule, between 30 and 50% of the total oil volume needs to be drained for the air conditioner to function properly.

Another reliable sign of system integrity is oil clarity. The unclean compressor oil in the image to the right makes it possible that the air conditioning system has another defect that is impairing the operation of the original compressor.

Instructions for Oil Balancing

Always refer to the instructions that came with the compressor or your vehicle’s manual when performing a compressor oil balance to determine how much oil to add to the compressor before mounting it on the vehicle.

Add the appropriate amount of oil. The majority of the time, oil balancing entails measuring and draining the oil from the malfunctioning compressor before adding a predetermined amount of fresh oil to the replacement compressor. The compressor manufacturer specifies how much oil should be put to the compressor.

Take note of the viscosity of the oil. Oil viscosity should be considered in addition to applying the appropriate amount of oil to a replacement compressor. Use the oil viscosity that the compressor’s manufacturer recommends. When lighter weight PAG 46 is used instead of greater weight PAG 150 oils, the compressor may operate noisily and wear out sooner than it should.

The compressor clutch should be turned. A helpful maintenance advice is to crank the compressor clutch at least four turns after adding the oil to the compressor before installing the compressor. This does two things. Rotating the clutch minimizes initial torque when the clutch is first engaged and circulates oil throughout the compressor, lowering the risk of compressor failure from dry bearings.

Some compressors have a high initial torque by design. When the compressor is turned on, if the torque is strong, it may cause the compressor drive belt to break or the engine to stall. Typically, a spanner wrench or your hand are used to turn the compressor clutch. The compressor turning tool is another alternative to the spanner wrench.