Manitowoc Ice STH003 manual HOT GAS Valve Analysis

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HOT GAS VALVE ANALYSIS

The valve can fail in two positions:

Valve will not open in the harvest cycle.

Valve remains open during the freeze cycle.

Valve will not open in the harvest cycle Although the circuit board has initiated a harvest cycle, the evaporator temperature remains unchanged from the freeze cycle.

Valve remains open in the freeze cycle: Symptoms are dependent on the amount of leakage in the freeze cycle. A small amount of leakage will cause increased freeze cycle times. A large amount of leakage will result in no ice produced.

Use the following procedure and table to help determine if a hot gas valve is remaining partially open during the freeze cycle.

1.Wait five minutes into the freeze cycle.

1.Feel the inlet of the hot gas valve(s).

IMPORTANT

Feeling the hot gas valve outlet or across the hot gas valve itself will not work for this comparison. The hot gas valve outlet is on the suction side (cool refrigerant). It may be cool enough to touch even if the valve is leaking.

WARNING

The inlet of the hot gas valve and the compressor discharge line could be hot enough to burn your hand. Just touch them momentarily

2.Feel the compressor discharge line.

3.Compare the temperature of the inlet of the hot gas valves to the temperature of the compressor discharge line.

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Contents CM050 CM Model Ice Machines Safety Notices Procedural Notices Potential Personal Injury Situation Read These Before ProceedingPersonal Injury Potential Table of Contents Liquid Line Thermistor Model Numbers CMS050A004Drain Pump Accessories LegsManitowoc ICE Machine Cleaner and Sanitizer MODEL/SERIAL Number Location General Owner Warranty Registration CardPage Manitowoc ICE, INC Location of ICE Machine InstallationHeat of Rejection Air Conditioning** Peak ICE Machine Heat of RejectionLevelers Legs Leveling the ICE MachineDrain Connections Water SERVICE/DRAINS Water SupplyWater Inlet Lines Water Supply and Drain Line SIZING/CONNECTIONS Drain PumpElectrical Requirements Voltage Electrical SpecificationsMinimum Circuit Ampacity Gfci RequirementsComponent Identification Water Pump Evaporator Shutter Assembly Power Button Green BIN Thermostat AdjustmentClean Green Operational ChecksSafety Timers ICE Machine Inspection Cleaning the CondenserAIR-COOLED Condenser Interior Cleaning and Sanitizing Place CLEANING/SANITIZING Procedure Interior Cleaning and Sanitizing GeneralPage Cleaning Procedure Page Page Removal of Parts for Cleaning and Sanitizing TOP Cover Water Shutters ICE Chute Sump Drain Overflow Tube Water Trough Spray BAR, Water Pump and Hose Spray BAR Disassembly SELF-CONTAINED AIR-COOLED ICE Machines Removal from SERVICE/LONG Term STORAGE/WINTERIZATION GeneralFreeze Refrigeration System Start-UpHarvest Automatic Shut-OffSequence Energized Parts Chart SELF-CONTAINED ICE MachinesDiagnosing AN ICE Machine That will not RUN TroubleshootingPage ICE Machine will not Harvest ICE Quality is Poor Cubes are SHALLOW, Incomplete or White Freeze Cycle is LONG, LOW ICE Production ICE Machine Runs & no ICE is Produced Freeze Harvest Cycle Psig Beginning Freeze Cycle Discharge Pressure LOW Checklist Analyzing Suction Pressure Step ProcedureDischarge Pressure Suction Pressure High Checklist ProblemSuction Pressure LOW Checklist Problem Normal Operation HOT GAS ValveGeneral HOT GAS Valve Analysis Freeze cycle. If Function SpecificationsNo Ice on Ice on Bulb Result Check ProcedureFreeze Time Harvest Time Total Cycle Time Additional finishing time check Adjusting Finishing TimeLiquid Line Thermistor SM50 Resistance Chart TEMPERATURE/RESISTANCE ChartTotal System Refrigeration Charge Component Specifications Check Procedures Single Phase Compressors Compressor Electrical DiagnosticsCheck Resistance OHM Values Check Motor Windings to GroundCompressor Drawing High Amps Compressor Drawing Locked RotorRelay CapacitorPage Cycle Times Freeze Time + Harvest Time = Cycle Time New Product Specifications RecoverRecycle ReclaimRefrigerant RE-USE Policy Page Connections Refrigerant Recovery/Evacuation/ChargingRecovery/Evacuation Charging Procedures Page System Contamination Cleanup General No symptoms or suspicion Normal Mild System Contamination Cleanup Procedure Change the vacuum pump oil Severe System Contamination Cleanup ProcedureFollow normal evacuation procedures Page FIG. a Pinching OFF Tubing Using Pinch Off ToolDo not disassemble valve Brazing Procedures for Danfoss Solenoid ValvesMAX F 700C Liquid Line Filter Drier Control Board Wiring Diagrams Tubing Schematic Manitowoc Ice, Inc