Manitowoc
Manitowoc Manitowoc
Hot Gas Valve AnalysisThe 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 CYCLEAlthough the circuit board has initiated a harvest cycle,the evaporator temperature remains unchanged fromthe freeze cycle.! CautionCoil must be seated 100% on solenoid to functioncorrectly. Inst all coil with a twisting motion toproperly seat.VALVE REMAINS OPEN IN THE FREEZE CYCLE:Symptoms of a hot gas valve remaining partially openduring the freeze cycle can be similar to symptoms ofan expansion valve, float valve or compressorproblem. Symptoms are dependent on the amount ofleakage in the freeze cycle.A small amount of leakage will cause increased freezetimes and an ice fill pattern that is “Thin at the Outlet”,but fills in at the end of the cycle.As the amount of leakage increases the length of thefreeze cycle increases and the amount of ice at theoutlet of the evaporator decreases.Refer to the Parts Manual for proper valve application.If replacement is necessary, use only “original”Manitowoc replacement parts.122 Part Number 80-01111-9 7/10
Use the following procedure and table to helpdetermine if a hot gas valve is remaining partially openduring the freeze cycle.1. Wait five minutes into the freeze cycle.2. Feel the inlet of the hot gas valve(s).ImportantFeeling the hot gas valve outlet or across the hotgas valve itself will not work for this comparison.The h ot g as val ve o utlet i s on the suction sid e(cool refrigerant). It may be cool enough to toucheven if the valve is leaking.3. Feel the compressor discharge line.! WarningThe inlet of the hot gas valve and the compressordischarge line could be hot enough to burn yourhand. Just touch them momentarily.4. Compare the temperature of the inlet of the hotgas valves to the temperature of the compressordischarge line.Part Number 80-01111-9 7/10 123
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Hot Gas Valve AnalysisThe 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 CYCLEAlthough the circuit board has initiated a harvest cycle,the evaporator temperature remains unchanged fromthe freeze cycle.! CautionCoil must be seated 100% on solenoid to functioncorrectly. Inst all coil with a twisting motion toproperly seat.VALVE REMAINS OPEN IN THE FREEZE CYCLE:Symptoms of a hot gas valve remaining partially openduring the freeze cycle can be similar to symptoms ofan expansion valve, float valve or compressorproblem. Symptoms are dependent on the amount ofleakage in the freeze cycle.A small amount of leakage will cause increased freezetimes and an ice fill pattern that is “Thin at the Outlet”,but fills in at the end of the cycle.As the amount of leakage increases the length of thefreeze cycle increases and the amount of ice at theoutlet of the evaporator decreases.Refer to the Parts Manual for proper valve application.If replacement is necessary, use only “original”<strong>Manitowoc</strong> replacement parts.122 Part Number 80-01111-9 7/10