OIL-A/C REFRIGERANT
DESCRIPTION
The refrigerant oil used in R-134a refrigerant systems is a synthetic-based, polyalkylene glycol (PAG), wax-free
lubricant. Mineral-based R-12 refrigerant oils are not compatible with PAG oils, and should never be introduced to
an R-134a refrigerant system.
There are different PAG oils available, and each contains a different additive package. The Denso 10S17 A/C com-
pressor used in this vehicle is designed to use ND-8 PAG refrigerant oil. Use only this type of refrigerant oil in the
refrigerant system.
OPERATION
After performing any refrigerant recovery or recycling operation, always replenish the refrigerant system with the
same amount of the recommended refrigerant oil as was removed. Too little refrigerant oil can cause A/C compres-
sor damage, and too much can reduce A/C system performance.
PAG refrigerant oil is more hygroscopic than mineral oil, and will absorb any moisture it comes into contact with,
even moisture in the air. The PAG oil container should always be kept tightly capped until it is ready to be used.
After use, recap the oil container immediately to prevent moisture contamination.
STANDARD PROCEDURE
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 accumulator, A/C condenser, A/C evaporator 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: The oil used in the Denso 10S17 A/C compressor is ND-8 PAG R-134a refrigerant oil. Only refrig-
erant oil of the same type should be used to service the A/C system. Do not use any other refrigerant oil.
The oil container should be kept tightly capped until it is ready for use and then tightly capped after use to
prevent contamination from dirt and moisture. 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 lubricant being removed during recovery. This
amount of lubricant should be added back into the system. Refer to the reclaim/recycling equipment man-
ufacturers instructions.
It will not be necessary to check the oil level in the A/C compressor or to add oil, unless there has been an oil loss.
An oil loss may occur due to a rupture or leak from a refrigerant line, a connector fitting, a component, or a com-
ponent seal. If a leak occurs, add 30 milliliters (1 fluid ounce) of 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 accumulator, A/C condenser or an A/C evaporator is replaced. See the
Refrigerant Oil Capacities chart. When an A/C compressor is replaced, the refrigerant oil must be drained from the
old compressor and measured. Drain all of the refrigerant oil from the new A/C compressor, then fill the new com-
pressor with the same amount of refrigerant oil that was drained out of the old compressor.
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PLUMBING
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