Hoshizaki KM-1301SWH-E, KM-1301SRH-E, KM-1301SAH-E IV. Service Diagnosis, Diagnostic Procedure

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IV. Service Diagnosis

WARNING

1.This unit should be diagnosed and repaired only by qualified service personnel to reduce the risk of death, electric shock, serious injury, or fire.

2.Risk of electric shock. Use extreme caution and exercise safe electrical practices.

3.Moving parts (e.g., fan blade) can crush and cut. Keep hands clear.

4.CHOKING HAZARD: Ensure all components, fasteners, and thumbscrews are securely in place after the unit is serviced. Make sure that none have fallen into the storage bin.

5.Make sure all food zones in the icemaker and storage bin are clean after the unit is serviced. For cleaning procedures, see "VI. Cleaning and Maintenance."

A. Diagnostic Procedure

The diagnostic procedure is basically a sequence check which can be used at unit startup or for system diagnosis. This procedure allows you to diagnose electrical system and component failures in normal operating conditions of 70°F (21°C) or warmer air and 50°F (10°C) or warmer water temperatures. Before conducting the diagnostic procedure, check for correct installation, proper voltage per unit nameplate, and adequate water supply. Check CB using the steps in "IV.B. Control Board Check." Check the dip switch settings to assure that S4 dip switch 3, 4, 7, 8, 9, & 10 and S5 dip switch 1 through 5 are in the factory default position. S4 dip switch 1, 2, 5, & 6 are cleaning adjustments and the settings are flexible. For factory default settings, see "II.C.2.a) Default Dip Switch Settings." As you go through the procedure, check to assure the components energize and de-energize correctly. If not, those components and controls are suspect.

1)Turn off the power supply, then access the control box. Clear any ice from BC.

2)Turn on the power supply, then move the control switch to the "ICE" position. A 5second delay occurs. CB red "POWER OK" LED and green "BC CLOSED" LED come on.

If red "POWER OK" LED is off on thermostatic BC unit (KM-1301SAH-E), clear ice away from the thermostatic bin control bulb in the storage bin area. If no ice is near the thermostatic bin control bulb or the LED does not come on even after clearing away ice, check thermostatic BC. See "IV.C.1. Thermostatic Bin Control Check." If yellow "BC OPEN" LED is on (indicating a full bin), confirm that CB K4 jumper is in place on thermostatic BC unit (KM1301SAH-E) or check BC on mechanical BC unit

(KM1301SWH-E, KM-1301SRH-E). See "IV.C.2.a) Mechanical Bin Control Check."

3)1-Minute Fill Cycle – LED 4 is on. WV and X2 relay (auxiliary code T-0, U0), X11 relay

(auxiliary code U-1 and later) energize and the 1-minute fill cycle begins. After 1 minute,

CB checks for a closed F/S. If F/S is closed, the harvest cycle begins. If closed, continue to step 4. If open, WV remains energized through additional 1minute fill cycles until water fills the tank and closes F/S (low water safety). Diagnosis: If WV does not open, check the supply voltage at WV terminals, check continuity on the coil, confirm the screen or external filter isn't plugged (no water flow). If unit fails to start harvest, check for open F/S or bad 1-minute timer in CB. See "IV.D. Float Switch Check and Cleaning" and "IV.B. Control Board Check."

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Contents Superior Degree Reliability Hoshizaki AMERICA, INC Contents Page Unit Important Safety InformationSerious injury Indicates important information about the use and careKM-1301SAH-E air-cooled Specifications IcemakerKM-1301SWH-E water-cooled KM-1301SRH-E remote air-cooled URC-14FE Condenser UnitSpecifications II. General Information Construction KM-1301SWH-E water-cooled Separators Initial Harvest Cycle Sequence of OperationSequence Cycles and Shutdown Minute Fill CycleHarvest Cycle S4 Dip Switch Setting Pump-Out 1st Pump-Out FrequencyFreeze Cycle Pump-Out CycleCycle at Shutdown Mechanical Bin Control Activation Mechanical Bin Control KM-1301SWH-E, KM-1301SRH-EMechanical BC Bin Full Shutdown and Restart Sequence Flow ChartCycle Steps Minute Fill Harvest Cycle Pump-Out CycleControl Board Control Board Control Board LayoutTime LEDs are On LED Lights and Audible Alarm SafetiesNo. of Beeps Type of Alarm Every 3 sec Sequence StepHarvest Timer S4 dip switch 1 Controls and AdjustmentsDefault Dip Switch Settings Time seconds Inlet Pump-Out Timer S4 dip switch 3Pump-Out Frequency Control S4 dip switch 5 S4 Dip Switch Setting Pump Motor Time seconds Harvest Pump Timer S4 dip switchFactory Use S4 dip switch Freeze Timer S4 dip switch 9Refill Counter S5 dip switch 2 through Control SwitchFloat Switch Control S5 dip switch Tank Water Tank Headmaster Service Drier Valve Thermistor U-0 Auxiliary Code Wiring DiagramsAuxiliary Code T-0, U-0 KM-1301SAH-E air-cooledAuxiliary Code U-1 and Later PressureSwitch KM-1301SRH-E remote air-cooled Performance Data 1335 13301240 17802070 12701142 1950Diagnostic Procedure IV. Service DiagnosisPage S4 Dip Switch Setting Pump-Out 1st Pump-Out Frequency Mechanical Bin Control KM-1301SWH-E, KM-1301SRH-E Shutdown Thermostatic Bin Control KM-1301SAH-EControl Board Check Mechanical Bin Control Check Bin Control CheckThermostatic Bin Control Check KM-1301SAH-E Stacked Unit Connection Detail Single Unit Connection DetailMechanical Bin Control Cleaning Float Switch Check Float Switch Check and CleaningFloat Switch Cleaning Thermistor Check Adjustment of Water Regulating Valve water-cooled modelNo Ice Production Possible Cause Diagnostic ChartsNo Ice Production No Ice Production Possible Cause Freeze Up Possible Cause Harvest Cycle Freeze UpFreeze Up Possible Cause Freeze Cycle Long Freeze Cycle Low Ice ProductionLow Ice Production Possible Cause Long Harvest Cycle Refrigerant Recovery Replacement of ComponentsService for Refrigerant Lines Evacuation and Recharge R-404A BrazingPage Component Important Notes for Component ReplacementCleaning Procedure VI. Cleaning and MaintenanceIce Chute Float Switch Assembly Drain Plug Sanitizing Procedure Following Cleaning Procedure Remove the water from the icemaker water supply line MaintenanceDrain the water tank