Sometimes a relatively small system issue can create expensive compressor damage. Liquid washout is one example. It occurs when refrigerant washes oil from internal surfaces and leaves critical components without the lubrication they need.
What Liquid Washout Looks Like
- Worn pistons and/or rings
- Worn cylinders
- Scored pins
- Scored and/or broken rods
- Worn bearings
- Scored crankshaft
What Is Happening Inside the Compressor?
During the off-cycle, saturated refrigerant can migrate into the crankcase. When the compressor starts, the refrigerant and oil form a foam that is pumped through the system, stripping bearing surfaces of the oil film necessary for proper lubrication. Washout is a milder form of slugging.
What to Check
- Check TXV bulb placement and superheat settings
- Verify the crankcase heater is functioning and remains on during the off-cycle
- Confirm the TXV is not oversized for the application
Washout can begin with refrigerant management and end with damaged internal components. Correcting the conditions that allow refrigerant to migrate into the crankcase helps protect lubrication and the compressor that goes back into service.
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