Manitowoc Ice S1800 Harvest Sequence 5. Water Purge, Automatic SHUT-OFF 7. Automatic Shut-Off

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Section 3

Ice Machine Operation

 

 

HARVEST SEQUENCE 5. Water Purge

The harvest valve(s) opens at the beginning of the water purge to divert hot refrigerant gas into the evaporator.

The water pump continues to run, and the water dump valve energizes for 45 seconds to purge the water in the sump trough. The water fill valve energizes (turns on) and de-energizes (turns off) strictly by time. The water fill valve energizes for the last 15 seconds of the 45-second water purge.

After the 45 second water purge, the water fill valve, water pump and dump valve de-energize. (Refer to “Water Purge Adjustment” for details.)

6. Harvest

The harvest valve(s) remains open and the refrigerant gas warms the evaporator causing the cubes to slide, as a sheet, off the evaporator and into the storage bin. The sliding sheet of cubes swings the water curtain out, opening the bin switch.

The momentary opening and re-closing of the bin switch terminates the harvest sequence and returns the ice machine to the freeze sequence (Step 3 - 4.)

When Used - The air compressor energizes after 35 seconds and remains energized throughout the entire harvest cycle. The air compressor will automatically energize for 60 seconds when the harvest cycle time exceeded 75 seconds in the previous cycle.

AUTOMATIC SHUT-OFF 7. Automatic Shut-Off

When the storage bin is full at the end of a harvest sequence, the sheet of cubes fails to clear the water curtain and will hold it open. After the water curtain is held open for 30 seconds, the ice machine shuts off. The ice machine remains off for 3 minutes before it can automatically restart.

The ice machine remains off until enough ice has been removed from the storage bin to allow the ice to fall clear of the water curtain. As the water curtain swings back to the operating position, the bin switch re-closes and the ice machine restarts (steps 1 - 2), provided the 3 minute delay period is complete.

SAFETY TIMERS

The control board has the following non-adjustable safety timers:

•The ice machine is locked into the freeze cycle for 6 minutes before a harvest cycle can be initiated. Freeze lock is bypassed after moving the toggle switch from OFF to ICE position for the first cycle only.

•The maximum freeze time is 60 minutes at which time the control board automatically initiates a harvest sequence (steps 5 & 6).

•The maximum harvest time is 3.5 minutes at which time the control board automatically initiates a freeze sequence (steps 3 & 4).

WARM WATER RINSE CYCLE

Closing the back of the evaporator allows ice to build up on the rear of the evaporator and the plastic evaporator frame parts. After 200 freeze/harvest cycles have been complete the control board will initiate a warm water rinse.

After the 200th harvest cycle ends:

•The Clean and Harvest LED’s energize to indicate the ice machine is in a warm water rinse.

•The compressor and harvest valve remain energized.

•The water pump energizes.

•The water inlet valve energizes until water contacts the water level probe.

•The compressor and harvest valve warm the water for 5 minutes, then de-energize.

•The water pump remains energized for an additional 5 minutes (10 minute total on time) then de- energizes.

NOTE: The warm water rinse cycle can be terminated by moving the toggle switch to the OFF position, then back to ICE.

Part Number 80-1634-3

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Contents Service Manual Personal Injury Potential Read These Before ProceedingTable of Contents Table of Contents Section Ice Machine Operation Section MaintenanceSection Before Calling For Service 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 StepMaintenance Section Sanitizing ProcedureSolution Type Water Mixed With Sanitizer Solution Type Water Mixed With Removal of Parts for CLEANING/SANITIZINGWater Curtain Water Curtain Removal Ice Thickness ProbeIce Thickness Probe Removal Water Distribution Tube Water TroughWater Distribution Tube Removal Water Level Probe Water PumpWater Pump Removal Water Dump Valve Dump Valve DisassemblyDrain Line Check Valve Evaporator Tray RemovalWater Inlet Valve Maintenance Section Removal from Service/Winterization Pry Open the Water Regulating Valve AUCS→ AccessorySELF-CONTAINED WATER-COOLED ICE Machines Problem Possible Cause To Correct ChecklistSafety Limit Feature Before Calling For Service SectionEnergized Parts Charts Section Electrical SystemSELF-CONTAINED WATER-COOLED Models Initial Start-Up or Start-Up After Automatic Shut-Off SELF-CONTAINED ModelsWater Purge Self-Contained Water PurgeRefrigeration System Start Up 5 Seconds Toggle Switch Refrigeration System START-UPSelf-Contained Refrigeration System Start-Up Freeze Sequence Electrical System SectionPRE-CHILL Self-Contained Pre-Chill Self-Contained ModelsToggle Switch Bin Switch Control Board Relays FreezeSelf-Contained Freeze Self-Contained Models Harvest Sequence Harvest Automatic Shut-Off Automatic SHUT-OFFSelf-Contained Automatic 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 SeizedPtcr Diagnostics What is a PTCR?Compressor Start Sequence 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 CircuitryProblem Water Trough Overfilling During Freeze Cycle Diagnosing Water Level Control CircuitryWait until the freeze cycle starts 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 minutesINSTALLATION/VISUAL Inspection Checklist Water System ChecklistPossible Problem Corrective Action ICE Formation Pattern Extremely Thin at Evaporator OutletNormal Ice Formation No Ice Formation Extremely Thin at Evaporator InletSafety Limits Safety Limit IndicationAnalyzing Why Safety Limits May Stop the Ice Machine 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 ChecklistHarvest Valve Temperature Check General Harvest Valve AnalysisFindings Comments 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-DRIERSTotal System Refrigerant Charges Series Version Charge S1800M48 oz 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
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