R-Pro › Field cases › Refrigeration systems
Oil Contamination (Carbonization or Metal Particles)
Likely causes
Metal particles from internal bearing/piston wear
Check: Take oil sample and check color/viscosity (normal: clear amber)
What to do: Take oil sample and check color/viscosity (normal: clear amber) → Recover all refrigerant and replace compressor → Simultaneously replace filter drier and suction strainer → Flush the circuit (nitrogen flush or flushing refrigerant) → Eliminate root cause (overheating/liquid slugging) before recharging
Oil carbonization from overheating (black discoloration)
Check: Recover all refrigerant and replace compressor
What to do: Recover all refrigerant and replace compressor → Simultaneously replace filter drier and suction strainer → Flush the circuit (nitrogen flush or flushing refrigerant) → Eliminate root cause (overheating/liquid slugging) before recharging
Refrigerant dilution of oil causing lubrication failure
Check: Simultaneously replace filter drier and suction strainer
What to do: Simultaneously replace filter drier and suction strainer → Flush the circuit (nitrogen flush or flushing refrigerant) → Eliminate root cause (overheating/liquid slugging) before recharging
Black oil or metal particles indicate internal wear or burnout. Compressor replacement and circuit flushing required. Replacing only the compressor without flushing the circuit will destroy the new compressor quickly. Always flush.
All 565 cases work offline in R-Pro, with error codes for 62 brands and P-T data for 108 refrigerants.
Open R-Pro →Related cases
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