Refrigerant Oil: Service and Repair
REFRIGERANT OIL LEVEL
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.
CAUTION: 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.
CAUTION: 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.
NOTE: 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 condenser, A/C receiver/drier or A/C evaporator is replaced. See the Refrigerant Oil Capacities chart.
The refrigerant oil level in a new A/C compressor must first be adjusted to the proper amount prior to compressor installation. See the COMPRESSOR OIL DRAIN PROCEDURES.
REFRIGERANT OIL CAPACITIES
COMPRESSOR OIL DRAIN PROCEDURE - VARIABLE DISPLACEMENT
CAUTION: Be certain to adjust the refrigerant system oil level when replacing an A/C compressor. The refrigerant oil in the Denso 6SEU16 A/C compressor can only be drained using the procedure 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.
If the Denso 6SEU16 A/C compressor is being replaced, some refrigerant oil must first be drained from the replacement A/C compressor. The 6SEU16 A/C compressor is filled with 100 milliliters (3.4 oz.) from the factory. Drain 50 milliliters (1.7 oz.) of refrigerant oil from the replacement 6SEU16 compressor. Use the following procedure to drain and measure refrigerant oil from the 6SEU16 A/C compressor.
1. Place the replacement A/C compressor (2) on a workbench and remove the drain plug (1).
CAUTION: The 6SEU16 A/C compressor is filled with 100 milliliters (3.4 oz.) from the factory. Drain 50 milliliters (1.7 oz.) of refrigerant oil from the new 6SEU16 compressor when replacing only the compressor.
NOTE: When replacing multiple A/C system components, see the Refrigerant Oil Capacities chart to determine how much oil should be removed from the replacement A/C compressor (example: new 6SEU16 compressor and receiver/drier requires 80 ml. (2.7 oz.) of oil to be added to the system. 100 ml. (3.4 oz.) of oil is in replacement compressor. 100 ml. (3.4 oz.) minus 80 ml. (2.7 oz.) equals 20 ml. (0.7 oz.) of oil to be drained from replacement compressor).
2. Position the replacement A/C compressor so that the refrigerant oil can drain out of the drain port into a suitable clean measured container. Hold the replacement A/C compressor in this position until the required amount of refrigerant oil is drained from the compressor.
CAUTION: Failure to properly adjust the refrigerant oil level prior to installation of a replacement compressor can prevent the A/C system from operating as designed and cause serious compressor damage.
3. Reinstall the drain plug. Tighten the drain plug securely.
4. Install the replacement A/C compressor onto the engine A/C Compressor - Installation.
COMPRESSOR OIL DRAIN PROCEDURE - FIXED DISPLACEMENT
CAUTION: Be certain to adjust the refrigerant system oil level when replacing an A/C compressor. Failure to properly drain and measure the refrigerant oil from the A/C compressor can prevent the A/C system from operating as designed and cause serious compressor damage.
The Denso 10SRE18 A/C compressor is filled with refrigerant oil from the factory. Use the following procedure to drain and measure refrigerant oil from the 10SRE18 A/C compressor.
1. Position the original A/C compressor so that the refrigerant oil can drain out of the suction and discharge ports into a suitable clean measured container. Hold the original A/C compressor in this position until all of the refrigerant oil is drained from the compressor.
2. Drain all of the refrigerant oil from the replacement A/C compressor into a clean measured container.
3. Refill the replacement A/C compressor with the same amount of refrigerant oil that was drained out of the original compressor. Use only clean refrigerant oil of the type recommended for the A/C compressor in the vehicle.
CAUTION: Failure to properly adjust the refrigerant oil level prior to installation of a replacement compressor can prevent the A/C system from operating as designed and cause serious compressor damage.
4. Install the replacement A/C compressor onto the engine A/C Compressor - Installation.