R-12 Systems

ADDING REFRIGERANT OIL
The compressor uses a special refrigerant oil. It is important that only the specified type and quantity of refrigerant oil be used in the compressor. If there is surplus oil in the system, too much oil will circulate with the refrigerant, reducing the cooling capacity of the system. Too little oil will result in poor lubrication of the compressor.

When it is necessary to replace a component of the refrigeration system, the correct procedures must be followed to ensure the total oil charge on the system is correct after the new component is installed. During normal A/C operation, some refrigerant oil is circulated through the system with the refrigerant and some is retained in the compressor. If certain components of the system are removed for replacement, some of the refrigerant oil will go with the component. To maintain the original total oil charge, it is necessary to compensate for the oil lost by adding oil to the system with the replacement part.

R-12 REFRIGERANT OIL
R-12 system vehicles require the use of a 500 viscosity mineral based refrigerant oil known as YN-9. This type of refrigerant oil was made specifically for R-12 systems and is not suitable for use in R-134a systems. Never use R-12 refrigerant oil YN-9 in R-134a systems.

CAUTION: Do not add R-134a refrigerant oil to an R-12 system. Also do not add R-12 refrigerant oil YN-9 to an R-134a system. Mixing these two types of refrigerant oils may cause poor lubricant circulation resulting in component failure and damage to the A/C systems.