R-Pro › Field cases › Refrigeration systems
Liquid Refrigerant Hammering (Liquid Hammer)
Likely causes
Expansion valve over-opened or faulty, supplying excess refrigerant
Check: Check suction pipe for frost during operation (frost = liquid ingestion)
What to do: Check suction pipe for frost during operation (frost = liquid ingestion) → Check expansion valve superheat setting (target 5–8K) → Verify refrigerant charge; recover some if overcharged → Check crankcase heater operation if equipped → Stop operation immediately if hammering recurs
Refrigerant overcharge
Check: Check expansion valve superheat setting (target 5–8K)
What to do: Check expansion valve superheat setting (target 5–8K) → Verify refrigerant charge; recover some if overcharged → Check crankcase heater operation if equipped → Stop operation immediately if hammering recurs
Refrigerant migrating to compressor during off cycle (crankcase heater failure)
Check: Verify refrigerant charge; recover some if overcharged
What to do: Verify refrigerant charge; recover some if overcharged → Check crankcase heater operation if equipped → Stop operation immediately if hammering recurs
Banging is caused by liquid refrigerant entering the compressor. Identify and eliminate the cause immediately to prevent damage. Ignoring liquid hammer will cause severe internal damage including valve breakage and connecting rod bending.
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
- Aging Room Humidity Control Failure (Unable to Maintain 85~95%RH)
- Ethylene Buildup in Meal Kit/Produce Warehouse — Over-Ripening Due to Ventilation Failure
- End-Zone Temperature Rise (Uneven Cooling)
- Air Curtain Weakening
- Excessive Temperature Rise After Defrost
- Excessive Heat Load from Direct Sunlight or Lighting