Proper oil levels in automotive air conditioning systems are vital to system performance. If the level is too low the compressor will starve for lubrication and fail. If the level is too high heat exchange is affected resulting in poor A/C performance. If a component has been replaced, or if a seal or leak left the system low on oil it must be replaced.
Refrigeration oil is distributed throughout the system in the refrigerant. If a leak is present on a hose or at a connection an oil spot will appear. This wet spot is likely collecting dirt and can be helpful in diagnosing the cause of a low refrigerant condition. Some oils contain dye that can be seen with a black light and special yellow tinted glasses. This dye can also be injected into a system with hard to find leaks to aid in visual diagnosis.
Always use manufacturers specifications and recommendations for adding oil to a system. Today's R134a systems use PAG (polyalkylene glycol) oil of different viscosities. PAG has replaced the mineral oil used in older R12 systems. This oil is highly hygroscopic meaning that it absorbs humidity from the air. Keep the lid on the container when your done and always add only the recommended amount for reasons mentioned earlier.
If the recovery machine is incapable of injecting oil into R134a A/C system after evacuation, use a manual refrigerant forced oil infector in the yellow line between the refrigerant container and the manifold gauge set.
No comments:
Post a Comment