Manitowoc

5. Install thermometer thermocouples on Suctionand Discharge line:• Digital thermometers with remotethermocouples must be used to obtaintemperatures• Suction and Discharge line thermocouplesmust be within 3" (76.2 mm) of the compressor• Thermocouples must be insulated• Doors and all panels must be in place• Initial freeze cycle is not used for diagnostics.Start monitoring temperatures 3 minutes intothe second freeze cycle.6. Compare Suction and Discharge temperatures to“QM45 Operating Temperatures” on page 207.The charts list Normal suction and dischargetemperatures.AnalysisDischargeLine TempSuctionLineTempIce FillPatternRefer toDiagnosticsfor:NormalNormalLess fill on theleft side of theevaporatorThis is normaloperationLow (20°F[-7°C] ormore)Low(20°F[-7°C] ormore)Less fill on theleft side of theevaporatorExpansionValveFloodingNormal orHighHigh(10°F[-12°C] ormore)Less fill on theleft side andtop 2 rows oftheevaporatorLow onRefrigerant/ExpansionValve StarvingNormalLow (5°F[-15°C] orless)Less fill on theleft side of theevaporatorRefrigerantOvercharge142 Part Number 80-01111-9 7/10