Hoshizaki KM-2400SRF3, KM-2400SRH3 service manual

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2)Defrost Timer

The defrost cycle starts when the Float Switch opens and completes the freeze cycle. But the Defrost Timer does not start counting until the Thermistor senses 48°F at the Evaporator outlet. The period from the end of the freeze cycle up to the point of the Thermistor's sensing varies depending on the ambient and water temperatures.

3)High Temperature Safety - 127 ± 7°F

The temperature of the suction line in the refrigerant circuit is limited by the High Temperature Safety.

During the defrost cycle the Evaporator temperature rises. The Thermistor senses 48°F and starts the Defrost Timer. After the Defrost Timer counts down to zero, the normal freeze cycle begins. If the Evaporator temperature continues to rise, the Thermistor will sense the rise in temperature and at 127 ± 7°F the Thermistor operates the High Temperature Safety.

This High Temperature Safety shuts down the circuit and the icemaker automatically stops. To reset the safety, turn the power off and back on again.

This High Temperature Safety protects the unit from excessive temperature. The Control Board will Beep every 3 seconds. The white Reset Button on the Control Board must be pressed with power on to reset the Safety.

4)Low Water Safety

If the Pump Motor is operated without water, the mechanical seal can fail. To prevent this type of failure, the Controller Board checks the position of the Float Switch at the end of the initial one minute water fill cycle and at the end of each defrost cycle.

If the Float Switch is in the up position (electrical circuit closed), the Controller Board changes to the ice making cycle. If the Float Switch is in the down position (electrical circuit open), the Controller Board changes to a one minute water fill cycle before starting the ice making cycle. This method allows for a Low Water Safety shut down to protect the Water Pump from mechanical seal failure.

5)High Voltage Cut-out

The maximum allowable supply voltage of this icemaker is limited by the High Voltage Cut-out.

If miswiring (especially on single phase 3 wire models) causes excessive voltage on the Controller Board, the High Voltage Cut-out shuts down the circuit in 3 seconds and the icemaker automatically stops. When the proper supply voltage is resumed, the icemaker automatically starts running again. The Control Board will signal this problem using 7 Beeps every 3 seconds.

6)LED Lights and Audible Alarm Safeties

The red LED indicates proper control voltage and will remain on unless a control voltage problem occurs. At startup, a 5 second delay occurs while the board conducts an internal timer check. A short beep occurs when the power switch is turned ON or OFF.

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Contents Stackable Crescent Cuber Hoshizaki AMERICA, INC Contents Maintenance Specifications Condensing UNIT, URC-24F Specifications Model URC-24F II. General Information Construction SOLID-STATE Control Features of Control Products E Controller BoardController Board Controller BoardPage Harvest Cycle Beep every 3 sec. = High Evaporator Temperature 127 FMinute Fill Cycle Freeze CycleControl Products HOSHIZAKI001 Board Control Products HOS-001A Board Sequence 1st Cycle 2nd Cycle and after with pump drain Important Water Valve opening is limited to 6 minutes2nd Cycle and after with no pump drain Controls and Adjustments OFFSetting Time Setting Frequency Checking the Controller Board Page III. Technical Information Wiring Diagram Timing Chart Page Performance Data IV. Service Diagnosis No ICE Production Problem Possible Cause RemedyController Board Problem Possible Cause Remedy Evaporator is Frozen UP ThermistorAbnormal ICE LOW ICE ProductionOthers Refrigerant Recovery Removal and Replacement of ComponentsService for Refrigerant Lines Evacuation and Recharge R-404ABrazing Removal and Replacement of Compressor Important Removal and Replacement of Drier Removal and Replacement of Expansion Valve Removal and Replacement of HOT GAS Valve and Line Valve Removal and Replacement of Evaporator Important Page Removal and Replacement of Thermistor Caution Removal and Replacement of FAN Motor Removal and Replacement of Water Valve Removal and Replacement of Pump MotorRemoval and Replacement of Spray Tubes VI. Cleaning and Maintenance Instructions Important Preparing the Icemaker for Long StoragePage Cleaning Procedure Cleaning Procedure Page Sanitizing Procedure Following Cleaning Procedure Maintenance