Manitowoc Ice S1800 service manual General

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Refrigeration System	Section 7

Operational Analysis (Diagnostics)

GENERAL

When analyzing the refrigeration system, it is important to understand that different refrigeration component malfunctions may cause very similar symptoms.

Also, many external factors can make good refrigeration components appear bad. These factors can include improper installation, or water system malfunctions such as hot incoming water supply or water loss.

The following two examples illustrate how similar symptoms can result in a misdiagnosis.

1.An expansion valve bulb that is not securely fastened to the suction line and/or not insulated will cause a good expansion valve to flood. If a service technician fails to check for proper expansion valve bulb mounting, he may replace the expansion valve in error.

The ice machine now functions normally. The technician erroneously thinks that the problem was properly diagnosed and corrected by replacing the expansion valve. Actually, the problem (loose bulb) was corrected when the technician properly mounted the bulb of the replacement expansion valve.

The service technician’s failure to check the expansion valve bulb for proper mounting (an external check) resulted in a misdiagnosis and the needless replacement of a good expansion valve.

2.An ice machine that is low on charge may cause a good expansion valve to starve. If a service technician fails to verify the system charge, he may replace the expansion valve in error.

During the replacement procedure, recovery, evacuation and recharging are performed correctly. The ice machine now functions normally. The technician erroneously thinks that the problem was properly diagnosed and corrected by replacing the expansion valve.

The service technician’s failure to check the ice machine for a low charge condition resulted in a misdiagnosis and the needless replacement of a good expansion valve.

When analyzing the refrigeration system, use the Refrigeration System Operational Analysis Table. This table, along with detailed checklists and references, will help prevent replacing good refrigeration components due to external problems.

7-4	Part Number 80-1634-3

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Contents Service Manual Read These Before Proceeding Personal Injury PotentialTable of Contents Section Maintenance Table of Contents Section Ice Machine OperationSection Before Calling For Service Table of Contents Section Electrical System Section Refrigeration SystemTable of Contents Ice Cube Sizes How to Read a Model NumberModel Numbers Self-Contained Water-CooledGeneral Information Section Accessories Section General Information Model/Serial Number Location Model/Serial Number LocationWarranty Coverage Electrical and AuCS Dimensions Ice Machine DimensionsWidth, Depth, and Height Dimensions GeneralS1800M Water-Cooled Installation Instructions Section Location of Ice MachineIce Machine Heat of Rejection Series Heat of Rejection Ice Machine Air ConditioningMinimum Circuit Ampacity Section Installation Instructions Electrical ServiceVoltage Electrical RequirementsSelf Contained ICE Machine 208-230/3/60 For United Kingdom OnlySelf Contained ICE Machine 115/1/60 or 208-230/1/60 Self Contained ICE Machine 230/1/50Water Inlet Lines Cooling Tower ApplicationsWater Supply Drain ConnectionsWater Supply and Drain Line SIZING/CONNECTIONS Installation Instructions SectionTypical Water Supply Drain Installation CondenserSection Installation Instructions Installation Check List AuCS Automatic Cleaning System Potential Personal Injury SituationSection Ice Machine Operation Component IdentificationIce Machine Operation Section Sequence Of Operation Initial START-UP or START-UP After Automatic SHUT-OFFHarvest Safety TimersHarvest Sequence 5. Water Purge Automatic SHUT-OFF 7. Automatic Shut-OffICE Thickness Check Ice Machine Operation Section Operational ChecksWater Level Ice Thickness CheckWater Purge Adjustment Harvest Sequence Water PurgeIce Machine Operation Section This page Intentionally Left BlankWater-Cooled Condenser Water Regulating Valve Exterior CleaningIce Machine Inspection AlphaSan→Sachet Replacement Frequency Maintenance Section GuardianInstallation Sachet Replacement ProcedureModel Amount of Cleaner Section Maintenance Interior Cleaning and SanitizingCleaning Procedure StepSanitizing Procedure Maintenance SectionSolution Type Water Mixed With Sanitizer Removal of Parts for CLEANING/SANITIZING Solution Type Water Mixed WithWater Curtain Removal Ice Thickness Probe Water CurtainIce Thickness Probe Removal Water Trough Water Distribution TubeWater Distribution Tube Removal Water Pump Water Level ProbeWater Pump Removal Dump Valve Disassembly Water Dump ValveEvaporator Tray Removal Drain Line Check ValveWater Inlet Valve Pry Open the Water Regulating Valve AUCS→ Accessory Maintenance Section Removal from Service/WinterizationSELF-CONTAINED WATER-COOLED ICE Machines Checklist Problem Possible Cause To CorrectBefore Calling For Service Section Safety Limit FeatureSection Electrical System Energized Parts ChartsSELF-CONTAINED WATER-COOLED Models Water Purge SELF-CONTAINED ModelsInitial Start-Up or Start-Up After Automatic Shut-Off Self-Contained Water PurgeRefrigeration System START-UP Refrigeration System Start Up 5 Seconds Toggle SwitchSelf-Contained Refrigeration System Start-Up PRE-CHILL Electrical System SectionFreeze Sequence Self-Contained Pre-Chill Self-Contained ModelsFreeze Toggle Switch Bin Switch Control Board RelaysSelf-Contained Freeze Self-Contained Models Harvest Sequence Harvest Automatic SHUT-OFF Automatic Shut-OffSelf-Contained Automatic Shut-Off Section Electrical System Wiring Diagrams Wiring Diagram LegendS1800 SELF-CONTAINED 1 Phase Control BoardS1800 SELF-CONTAINED 3 Phase BIN Switch SpecificationsCheck Procedure Main FuseContinuity Test SymptomsDiagnostic Aids Water Curtain Removal NotesCheck Motor Windings to Ground Compressor Electrical DiagnosticsCheck Resistance Ohm Values Determine if the Compressor is SeizedWhat is a PTCR? Ptcr DiagnosticsCompressor Start Sequence Model Automatic Shut-Off and Restart Troubleshooting PTCR’sWHY a Good Ptcr MAY Fail To Start the Compressor During Start-Up First .25 1.0 SecondsModel Manitowoc Cera-Mite Room Checking the PtcrManitowoc Ptcr Part NumberRelay Diagnosing Start ComponentsCapacitor Relay Operation CheckICE/OFF/CLEAN Toggle Switch Switch Setting Terminals Ohm ReadingElectronic Control Board Control BoardSafety Limits InputsHOW the Probe Works Freeze Time LOCK-IN FeatureIce Thickness Probe Cleaning Harvest LightDiagnosing ICE Thickness Control Circuitry Monitoring of Harvest Light CorrectionWater Level Probe Light Water Inlet Valve Safety SHUT-OFFElectrical System Section Water Level Control Circuitry Freeze Cycle CircuitryDiagnosing Water Level Control Circuitry Problem Water Trough Overfilling During Freeze CycleWait until the freeze cycle starts On or OFF Step Check Self Contained 1 Phase with Terminal Board SELF-CONTAINED Water -COOLED Models Freeze Cycle Refrigeration SequenceRefrigeration System Section S1800 SELF-CONTAINED Tubing Schematic General ICE Production Check Before Beginning ServiceWeights are in pounds Times are in minutesWater System Checklist INSTALLATION/VISUAL Inspection ChecklistPossible Problem Corrective Action Extremely Thin at Evaporator Outlet ICE Formation PatternNormal Ice Formation Extremely Thin at Evaporator Inlet No Ice FormationSafety Limit Indication Safety LimitsAnalyzing Why Safety Limits May Stop the Ice Machine Safety Limit Notes Possible Cause Check/CorrectSection Refrigeration System Freeze Cycle Discharge Pressure Low Checklist ProcedureFreeze Cycle Discharge Pressure High Checklist Analyzing Discharge Pressure During Freeze or Harvest CycleStep Example Using SY1004A Model Ice Machine Analyzing Suction Pressure During Freeze CycleFreeze Cycle Suction Pressure High Checklist Freeze Cycle Suction Pressure Low ChecklistHarvest Valve Analysis Harvest Valve Temperature Check GeneralFindings Comments Discharge Line Temperature Analysis General Column 2 LOW CHARGE/TXV Starving Final AnalysisColumn 1 Harvest Valve Leaking Column 3 TXV FloodingRefrigeration System Operational Analysis Tables Models Dual Expansion Valve Ice Machine Model NumberHigh Pressure CUT-OUT Hpco Control Hour Ice Production S1800 SeriesSelf-Contained Water-Cooled Cycle Times Operating PressuresSELF-CONTAINED RECOVERY/EVACUATION ConnectionsSelf-Contained Charging Procedures Charging ConnectionsSystem Contamination CLEAN-UP Determining Severity Of ContaminationMild System Contamination Cleanup Procedure Severe System Contamination Cleanup ProcedureSection Refrigeration System 10. Using Pinch-Off Tool FILTER-DRIERS Drier End Part Model Connection Size NumberSeries Version Charge S1800M Total System Refrigerant Charges48 oz Refrigerant Definitions RecoverNew Product Specifications RecycleNew Refrigerant Recovered or Recycled RefrigerantRefrigerant RE-USE Policy Reclaimed RefrigerantHFC Refrigerant Questions and Answers This page Intentionally Left Blank Page Attend a Manitowoc Factory Service School