Contents: Technical characteristics of oils ⇓ Handling oil ⇓ Checking the oil level in the…⇓ Filling the compressor with oil ⇓ Replacement of parts ⇓
Technical characteristics of oils
1. The HFC-134a system uses synthetic (PAG) compressor oil, while the R-12 system uses mineral oil. These two types of oil cannot be mixed.
2. Compressor oil grade (PAG) varies depending on the compressor model. Use only the grade specified for the compressor model.
Handling oil
1. Do not allow moisture, dust, metal particles, etc. to enter the oil.
2. Do not mix oils of different brands.
3. When oil is exposed to air for a long time, its moisture content increases. After filling and topping up the oil, immediately close the container tightly (compressor oil of the HFC-134a system absorbs moisture very quickly).
4. Compressor oils must be stored only in metal containers. Storing oils in plastic containers is prohibited.
Checking the oil level in the compressor
The compressor lubricating oil circulates in the system during operation. In all cases where system parts are replaced or a large amount of refrigerant leaks, add oil to restore its original amount. Total oil volume in the system: 120±10cm³.
Filling the compressor with oil
Oil and refrigerant have similar properties. During normal operation, some of the oil circulates in the system together with the refrigerant. Before checking the oil level in the system or replacing any system components, it is necessary to turn on the compressor for a while to ensure that the oil is filled. This procedure is performed in the following order:
1. Open all doors and the engine hood.
2. Start the engine; turn the air conditioner switch to the ON position and set the fan motor control knob to the position corresponding to the maximum rotation speed.
3. Leave the compressor running for 20 minutes at a speed of 800...1,000 rpm to activate the system.
4. Stop the engine.
Replacement of parts
When replacing system elements, it is necessary to fill the installed elements with the following volumes of oil.
When replacing a compressor, subtract the volume of refrigerant drained from the removed compressor from the specified volume and drain the resulting volume from the new compressor:
Specified oil volume in the compressor - Oil volume in the compressor being replaced = Volume of oil to be drained from the new compressor.
Note: Even if the compressor being replaced was oil-free, do not drain more than 50 cm³ of oil from the new compressor.