R-ProField casesRefrigeration systems

Debris Blockage (Sludge or Welding Residue)

Likely causes

Flux or oxide residue from pipe brazing

Check: Remove and clean TXV inlet screen

What to do: Remove and clean TXV inlet screen → For capillary: replace drier and backflush with nitrogen → Recover all refrigerant and replace filter drier → Nitrogen flush the circuit → Evacuate, recharge, and confirm pressures and superheat are normal

Sludge from oil degradation

Check: For capillary: replace drier and backflush with nitrogen

What to do: For capillary: replace drier and backflush with nitrogen → Recover all refrigerant and replace filter drier → Nitrogen flush the circuit → Evacuate, recharge, and confirm pressures and superheat are normal

Copper or iron particles in circuit

Check: Recover all refrigerant and replace filter drier

What to do: Recover all refrigerant and replace filter drier → Nitrogen flush the circuit → Evacuate, recharge, and confirm pressures and superheat are normal

Field tip

Debris is blocking the expansion valve or capillary tube. Clean the screen and replace the filter drier. Recurrence is likely if the source of debris (poor brazing, oil degradation) is not addressed.

All 565 cases work offline in R-Pro, with error codes for 62 brands and P-T data for 108 refrigerants.

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