Standard Procedure - Refrigerant Oil Level: Notes
When an A/C system is assembled at the factory, all components except the A/C compressor are refrigerant oil free. After the refrigerant system has been charged and operated, the refrigerant oil in the A/C compressor is dispersed throughout the refrigerant system. The A/C receiver/drier, A/C evaporator, A/C condenser and the A/C compressor will each retain a significant amount of the needed refrigerant oil.
It is important to have the correct amount of refrigerant oil in the A/C system. This ensures proper lubrication of the A/C compressor. Too little oil will result in damage to the A/C compressor, while too much oil will reduce the cooling capacity of the A/C system and consequently result in higher discharge air temperatures.
Be certain to adjust the refrigerant system oil level when replacing an A/C compressor. Drain the refrigerant oil from the A/C compressor using the procedures described below. Failure to properly drain the refrigerant oil from the A/C compressor can prevent the A/C system from operating as designed and cause serious compressor damage.
ND-8 PAG refrigerant oil is used in the A/C system. Only refrigerant oil of the same type should be used to service this R-134a A/C system. Do not use any other refrigerant oil. The refrigerant oil container should be kept tightly capped until it is ready for use and then tightly capped after use to prevent contamination from moisture and dirt. Refrigerant oil will quickly absorb any moisture it comes in contact with, therefore, special effort must be used to keep all R-134a system components moisture-free. Moisture in the refrigerant oil is very difficult to remove and will cause a reliability problem with the A/C compressor.
Most reclaim/recycling equipment will measure the amount of refrigerant oil being removed during the recovery process. This amount of refrigerant oil should always be added back into the refrigerant system. Refer to the reclaim/recycling equipment manufacturers instructions.
It will not be necessary to check the oil level within the A/C refrigerant system or to add oil, unless there has been an oil loss. A refrigerant oil loss may occur due to component replacement or a rupture or leak from a refrigerant line, connector fitting, component or component seal. If a leak does occurs, add 30 milliliters (1 fluid ounce) of the recommended refrigerant oil to the refrigerant system after the repair has been made. Refrigerant oil loss will be evident at the leak point by the presence of a wet, shiny surface around the leak.
Refrigerant oil must be added when an A/C receiver/drier, A/C evaporator or A/C condenser is replaced. Refer to the Refrigerant Oil Capacities charts.
The refrigerant oil level in a new A/C compressor must first be adjusted prior to compressor installation. Refer to the following COMPRESSOR OIL DRAIN PROCEDURE.
| Component | ml. | oz. |
|---|---|---|
| Total System Fill | 100 | 3.4 |
| A/C Receiver/drier | 30 | 1.0 |
| A/C Condenser | 10 | 0.3 |
| A/C Evaporator | 10 | 0.3 |
| A/C Compressor - Variable displacement | 50 | 1.7 |
| (Refer to COMPRESSOR OIL DRAIN PROCEDURE - VARIABLE DISPLACEMENT) | ||
| A/C Compressor - Fixed displacement | Drain and measure the oil from the old compressor. | |
| (Refer to COMPRESSOR OIL DRAIN PROCEDURE - FIXED DISPLACEMENT). | ||