Manitowoc Ice S1800 service manual Section Refrigeration System

Page 77

Section 7	Refrigeration System

Safety Limit #2

Refer to page 7-11 for safety limit operation.

Harvest time exceeds 3.5 minutes for 500 consecutive harvest cycles.

Possible Cause	Check/Correct
Improper installation	See “Installation/Visual Inspection Checklist”
Water system	Water area (evaporator) dirty
	Dirty/defective water dump valve
	Vent tube not installed on water outlet drain
	Water freezing behind evaporator
	Plastic extrusions and gaskets not securely mounted to the
	evaporator
	Low water pressure [20 psi (138 kPa) min.]
	Loss of water from sump area
	Clogged water distribution tube
	Dirty/defective water fill valve
	Defective water pump
Electrical system	Ice thickness probe out of adjustment
	Ice thickness probe dirty
	Bin switch defective
	Premature harvest
Refrigeration system	Non-Manitowoc components
	Water regulating valve dirty/defective
	Improper refrigerant charge
	Defective harvest valve
	TXV flooding (check bulb mounting)

SAFETY LIMIT NOTES

•Because there are many possible external problems, do not limit your diagnosis to only the items listed in this chart.

•A continuous run of 100 harvests automatically erases the safety limit code.

•The control board will store and indicate only one safety limit – the last one exceeded.

•If the toggle switch is moved to the OFF position and then back to the ICE position prior to reaching the 100-harvest point, the last safety limit exceeded will be indicated.

•If a Safety Limit light did not flash prior to the ice machine restarting, then the ice machine did not stop because it exceeded a safety limit.

Part Number 80-1634-3

7-11

Image 77

Contents Service Manual Personal Injury Potential Read These Before ProceedingTable of Contents Section Before Calling For Service Table of Contents Section Ice Machine OperationSection Maintenance Section Refrigeration System Table of Contents Section Electrical SystemTable of Contents Model Numbers How to Read a Model NumberIce Cube Sizes Self-Contained Water-CooledGeneral Information Section Accessories Model/Serial Number Location Section General Information Model/Serial Number LocationWarranty Coverage Width, Depth, and Height Dimensions Ice Machine DimensionsElectrical and AuCS Dimensions GeneralIce Machine Heat of Rejection Installation Instructions Section Location of Ice MachineS1800M Water-Cooled Series Heat of Rejection Ice Machine Air ConditioningVoltage Section Installation Instructions Electrical ServiceMinimum Circuit Ampacity Electrical RequirementsSelf Contained ICE Machine 115/1/60 or 208-230/1/60 For United Kingdom OnlySelf Contained ICE Machine 208-230/3/60 Self Contained ICE Machine 230/1/50Water Supply Cooling Tower ApplicationsWater Inlet Lines Drain ConnectionsTypical Water Supply Drain Installation Installation Instructions SectionWater Supply and Drain Line SIZING/CONNECTIONS CondenserSection Installation Instructions Installation Check List Potential Personal Injury Situation AuCS Automatic Cleaning SystemComponent Identification Section Ice Machine OperationInitial START-UP or START-UP After Automatic SHUT-OFF Ice Machine Operation Section Sequence Of OperationHarvest Sequence 5. Water Purge Safety TimersHarvest Automatic SHUT-OFF 7. Automatic Shut-OffWater Level Ice Machine Operation Section Operational ChecksICE Thickness Check Ice Thickness CheckHarvest Sequence Water Purge Water Purge AdjustmentThis page Intentionally Left Blank Ice Machine Operation SectionIce Machine Inspection Exterior CleaningWater-Cooled Condenser Water Regulating Valve AlphaSan→Installation Maintenance Section GuardianSachet Replacement Frequency Sachet Replacement ProcedureCleaning Procedure Section Maintenance Interior Cleaning and SanitizingModel Amount of Cleaner StepSolution Type Water Mixed With Sanitizer Maintenance SectionSanitizing Procedure Solution Type Water Mixed With Removal of Parts for CLEANING/SANITIZINGIce Thickness Probe Removal Water CurtainWater Curtain Removal Ice Thickness Probe Water Distribution Tube Removal Water Distribution TubeWater Trough Water Pump Removal Water Level ProbeWater Pump Water Dump Valve Dump Valve DisassemblyDrain Line Check Valve Evaporator Tray RemovalWater Inlet Valve SELF-CONTAINED WATER-COOLED ICE Machines Maintenance Section Removal from Service/WinterizationPry Open the Water Regulating Valve AUCS→ Accessory Problem Possible Cause To Correct ChecklistSafety Limit Feature Before Calling For Service SectionSELF-CONTAINED WATER-COOLED Models Energized Parts ChartsSection Electrical System Initial Start-Up or Start-Up After Automatic Shut-Off SELF-CONTAINED ModelsWater Purge Self-Contained Water PurgeSelf-Contained Refrigeration System Start-Up Refrigeration System Start Up 5 Seconds Toggle SwitchRefrigeration System START-UP Freeze Sequence Electrical System SectionPRE-CHILL Self-Contained Pre-Chill Self-Contained ModelsSelf-Contained Freeze Self-Contained Models Toggle Switch Bin Switch Control Board RelaysFreeze Harvest Sequence Harvest Self-Contained Automatic Shut-Off Automatic Shut-OffAutomatic SHUT-OFF Wiring Diagram Legend Section Electrical System Wiring DiagramsControl Board S1800 SELF-CONTAINED 1 PhaseS1800 SELF-CONTAINED 3 Phase Check Procedure SpecificationsBIN Switch Main FuseDiagnostic Aids SymptomsContinuity Test Water Curtain Removal NotesCheck Resistance Ohm Values Compressor Electrical DiagnosticsCheck Motor Windings to Ground Determine if the Compressor is SeizedCompressor Start Sequence Ptcr DiagnosticsWhat is a PTCR? WHY a Good Ptcr MAY Fail To Start the Compressor Troubleshooting PTCR’sModel Automatic Shut-Off and Restart During Start-Up First .25 1.0 SecondsManitowoc Ptcr Checking the PtcrModel Manitowoc Cera-Mite Room Part NumberCapacitor Diagnosing Start ComponentsRelay Relay Operation CheckSwitch Setting Terminals Ohm Reading ICE/OFF/CLEAN Toggle SwitchControl Board Electronic Control BoardInputs Safety LimitsIce Thickness Probe Cleaning Freeze Time LOCK-IN FeatureHOW the Probe Works Harvest LightMonitoring of Harvest Light Correction Diagnosing ICE Thickness Control CircuitryElectrical System Section Water Level Control Circuitry Water Inlet Valve Safety SHUT-OFFWater Level Probe Light Freeze Cycle CircuitryWait until the freeze cycle starts Problem Water Trough Overfilling During Freeze CycleDiagnosing Water Level Control Circuitry On or OFF Step Check Self Contained 1 Phase with Terminal Board Freeze Cycle Refrigeration Sequence SELF-CONTAINED Water -COOLED ModelsRefrigeration System Section S1800 SELF-CONTAINED Tubing Schematic General Weights are in pounds Before Beginning ServiceICE Production Check Times are in minutesPossible Problem Corrective Action INSTALLATION/VISUAL Inspection ChecklistWater System Checklist Normal Ice Formation ICE Formation PatternExtremely Thin at Evaporator Outlet No Ice Formation Extremely Thin at Evaporator InletAnalyzing Why Safety Limits May Stop the Ice Machine Safety LimitsSafety Limit Indication Possible Cause Check/Correct Safety Limit NotesSection Refrigeration System Freeze Cycle Discharge Pressure High Checklist ProcedureFreeze Cycle Discharge Pressure Low Checklist Analyzing Discharge Pressure During Freeze or Harvest CycleAnalyzing Suction Pressure During Freeze Cycle Step Example Using SY1004A Model Ice MachineFreeze Cycle Suction Pressure Low Checklist Freeze Cycle Suction Pressure High ChecklistFindings Comments Harvest Valve Temperature Check GeneralHarvest Valve Analysis Discharge Line Temperature Analysis General Column 1 Harvest Valve Leaking Final AnalysisColumn 2 LOW CHARGE/TXV Starving Column 3 TXV FloodingModels Dual Expansion Valve Ice Machine Model Number Refrigeration System Operational Analysis TablesHigh Pressure CUT-OUT Hpco Control Self-Contained Water-Cooled Cycle Times S1800 SeriesHour Ice Production Operating PressuresConnections SELF-CONTAINED RECOVERY/EVACUATIONCharging Connections Self-Contained Charging ProceduresDetermining Severity Of Contamination System Contamination CLEAN-UPSevere System Contamination Cleanup Procedure Mild System Contamination Cleanup ProcedureSection Refrigeration System 10. Using Pinch-Off Tool Drier End Part Model Connection Size Number FILTER-DRIERS48 oz Total System Refrigerant ChargesSeries Version Charge S1800M New Product Specifications RecoverRefrigerant Definitions RecycleRefrigerant RE-USE Policy Recovered or Recycled RefrigerantNew Refrigerant Reclaimed RefrigerantHFC Refrigerant Questions and Answers This page Intentionally Left Blank Page Attend a Manitowoc Factory Service School