RWB II ROTARY SCREW COMPRESSOR UNITS
MAINTENANCE
S70-200 IOM
Page 35
TROUBLESHOOTING THE RWB II COMPRESSOR
SYMPTOM
PROBABLE CAUSES and CORRECTIONS
EXCESSIVE NOISE and VIBRATION
Main oil injection valve may be closed. Open valve.
Bearing damage or excessive wear. CONTACT Frick Factor or Frick.
Coupling loose on shaft. Tighten coupling. Replace if damaged.
Misalignment between motor and compressor. Realign motor and compressor.
Refrigerant flood back. Correct system problem.
SLIDE VALVE and/or SLIDE STOP
4-way hydraulic control valve failed - repair or replace.
WILL NOT MOVE
Slide stop indicator rod stuck. Contact Frick Factor or Frick for assistance.
Check both S.V. and S.S. potentiometer for wiring and resistance.
Compressor must be running with sufficient oil pressure.
Unloader piston stuck. Contact Frick Factor or Frick for assistance.
Slipper seals worn out or damaged. Contact Frick Factor or Frick for assistance.
NOTE: Troubleshooting the compressor is limited to identifying the probable cause. If a mechanical problem is suspected, contact the
Frick Service Department. DO NOT ATTEMPT TO DISASSEMBLE COMPRESSOR.
TROUBLESHOOTING THE OIL SEPARATION SYSTEM
SYMPTOM
PROBABLE CAUSES and CORRECTIONS
GRADUAL OIL LOSS WITH AN OIL
Maintaining too high an oil level, lower level.
LEVEL IN THE COALESCER
SECTION SIGHT GLASS
Refrigerant carryover or liquid injection overfeeding, correct operation.
Loss of suction superheat. Adjust evaporator feeds.
Contaminated oil, damaged or not seated coalescer filter elements. Replace
oil charge and coalescers.
Oil float return valve closed, open return valve.
Float equalizing valve closed, open valve.
Coalescing oil return line strainer blocked, clean
Clean and check needle valve.
RAPID LOSS WITH NO OIL LEVEL
On shutdown, compressor unit suction check valve did not close, repair valve.
IN THE COALESCER SECTION
SIGHT GLASS
Suction check valve bypass valve open, close valve.
Coalescers loose or not seated properly, correct or replace.
