Loss of oil is a result of insufficient oil within the crankcase to properly lubricate all load bearing surfaces. When there is not enough refrigerant mass flow in the system to return oil to the compressor as fast as it is pumped out, there will be a uniform wearing and/or scoring on load bearing surfaces.

How to identify loss of oil.

• All rods and bearings worn or scored
• Crankshaft uniformly scored
• Rods broken from seizure
• Little or no oil in the crankcase

Primary causes of oil loss.

• Poor piping
• Improper traps
• Inadequate defrosts
• Loss of charge
• Short cycling
• Low loads
• Plugged oil filter

Ways to correct oil loss.

• Check oil failure control operation if applicable
• Check system refrigerant charge
• Correct abnormally low load conditions or short cycling
• Check for incorrect pipe sizes and/or oil traps
• Check for inadequate defrosts