Hoshizaki KM-901MAH, KM-901MWH, KM-901MRH/3 service manual Problem Possible Cause Remedy

Page 61

Problem

Possible Cause

 

Remedy

 

 

 

 

[1] The icemaker will not

h) Transformer

1. Coil winding open or

1. Replace.

start. (continued)

 

 

shorted.

 

 

i)

Wiring to Control Board

1. Loose connections or

1. Check for continuity and

 

 

 

open.

replace.

 

 

 

 

 

 

j)

Interlock Switch

1. Open position.

1. Move to closed position.

 

 

(Cleaning Valve)

 

 

 

 

2. Bad contacts.

2. Check for continuity and

 

 

 

 

 

 

 

replace.

 

 

 

 

 

k) Mechanical Bin Control

1. Movement restricted.

1. Check and free.

 

 

 

2. Defective

2. See "IV.C.2. Mechanical

 

 

 

 

Bin Control Check and

 

 

 

 

Cleaning."

 

l)

Thermistor

1. Leads shorted or open

1. See "IV.E. Thermistor

 

 

 

and high temperature

Check."

 

 

 

or harvest backup

 

 

 

 

timer safety operates

 

 

 

 

(1 beep or 2 beep

 

 

 

 

alarm).

 

 

 

 

 

 

m)Hot Gas Valve

1. Continues to open

1. Check for hot gas valve

 

 

 

in freeze cycle and

stuck open and replace.

 

 

 

freeze timer safety

 

 

 

 

operates (3 beep

 

 

 

 

alarm).

 

 

 

 

 

 

n) Inlet Water Valve

1. Mesh filter or orifice

1. Clean.

 

 

 

gets clogged and

 

 

 

 

water supply cycle

 

 

 

 

does not finish.

 

 

 

 

 

 

 

 

 

2. Coil winding open.

2. Replace.

 

 

 

3. Wiring to inlet water

3. Check for loose connection

 

 

 

valve.

or open, and replace.

 

 

 

 

 

o) Float Switch

1. Bad contacts.

1. Check for continuity and

 

 

 

 

replace.

 

 

 

 

 

 

 

 

2. Defective switch.

2. Clean or replace. See "IV.

 

 

 

 

D. Float Switch Check and

 

 

 

 

Cleaning."

 

 

 

 

 

p) Control Board

1. Defective or in alarm.

1. See "IV.B. Control Board

 

 

 

 

Check."

[2] Fill cycle will not

a) Water Supply

1. Water supply off or

1. Check and get

terminate.

 

 

pressure too low.

recommended pressure.

 

 

 

 

 

b) Float Switch

1. Connector

1. Reconnect.

 

 

 

disconnected.

 

 

 

 

 

 

 

 

 

2. Float does not move

2. Clean or replace. See "IV.

 

 

 

freely or switch

D. Float Switch Check and

 

 

 

defective switch.

Cleaning."

 

 

 

 

 

c) Control Board

1. Defective.

1. See "IV.B. Control Board

 

 

 

 

Check."

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Image 61
Contents KM-901MAH KM-901MWH Hoshizaki AMERICA, INC Contents Page Page Serious injury Important Safety InformationIndicates important information about the use and care Unit1a. KM-901MAH air-cooled Auxiliary Code T-0, U-0 Specifications Icemaker1b. KM-901MAH air-cooled Auxiliary Code U-1 and Later Water Cooled Condenser 2a. KM-901MWH water-cooled Auxiliary Code T-0, U-02b. KM-901MWH water-cooled Auxiliary Code U-1 and Later 3a. KM-901MRH remote air-cooled Auxiliary Code T-0, U-0 3b. KM-901MRH remote air-cooled Auxiliary Code U-1 and Later 4a. KM-901MRH3 remote air-cooled Auxiliary Code T-0, U-0 4b. KM-901MRH remote air-cooled Auxiliary Code U-1 and Later Condenser Unit Model URC-9F SpecificationsKM-901MAH air-cooled II. General Information ConstructionKM-901MWH water-cooled KM-901MRH/3 remote air-cooled Sequence Cycles and Shutdown Sequence of OperationControl Board Auxiliary Code T-0, U-0 Control Board Auxiliary Code U-1 and Later ShutdownOFF Cycle at Shutdown Mechanical Bin Control Activation Sequence Flow Chart Control Board Sequence Flow ChartCycle Bin FullLater Control Board Auxiliary Code U-1Minute Harvest Cycle Freeze Cycle Pump-Out Cycle Fill CycleControl Board Control Board Control Board LayoutPart Number 2A3792-01 High Temperature Safety Harvest Backup Timer and Freeze TimerLow Water Safety Maximum Water Supply Period 6 minutesNo. of Beeps Type of Alarm Every 3 sec LED Lights and Audible Alarm SafetiesSequence Step Energized Time LEDs are On Components Min Max AvgControl Board Auxiliary Code U-1 and Later Default Dip Switch Settings Controls and AdjustmentsHarvest Timer S4 dip switch 1 S4 Dip Switch S4 Dip Switch NoPump-Out Frequency Control S4 dip switch 5 Pump-Out Timer S4 dip switch 3S4 Dip Switch Setting Time seconds Inlet Factory Use S4 dip switch Bin Control Selector/Harvest Pump Timer S4 dip switchControl Board S4 Dip Switch Setting Bin Control Control Board S4 Dip Switch Setting Pump Motor Time secondsFloat Switch Control S5 dip switch 1 G Control Board Freeze Timer S4 dip switch 9Refill Counter S5 dip switch 2 through 5 G Control Board S4 Dip Switch Setting Time MinutesControl Switch Float SwitchBin Control ThermistorWater Pump Switch Discharge Line ModelCooled-AirWater-Cooled Model PressureHigh* Switch Wiring DiagramsKM-901MAH air-cooled and KM-901MWH water-cooled KM-901MRH remote air-cooled PressureSwitchHigh KM-901MRH3 remote air-cooled Cooled-AirModel High* Pressure Switch Cooled-WaterModelHigh Pressure Switch SwitchPressure Performance Data 835 9121480 1570KM-901MRH remote air-cooled KM-901MRH3 remote air-cooled Diagnostic Procedure IV. Service DiagnosisPage OFF Shutdown Thermostatic Bin Control Auxiliary Code T-0, U-0 Control Board CheckControl Correct LED Board Lighting Sequence Bin Control CheckMechanical Bin Control Check Mechanical Bin Control Cleaning Float Switch Check Float Switch Check and CleaningFloat Switch Cleaning Thermistor Check Problem Possible Cause Remedy Diagnostic ChartsNo Ice Production Problem Possible Cause Remedy Problem Possible Cause Remedy Evaporator is Frozen Up Problem Possible Cause Remedy Low Ice Production Abnormal Ice Other Service for Refrigerant Lines Removal and Replacement of ComponentsRefrigerant Recovery Evacuation and Recharge R-404A BrazingRemoval and Replacement of Compressor Removal and Replacement of Expansion Valve Page Removal and Replacement of Evaporator Removal and Replacement of Air-Cooled Condenser Removal and Replacement of Water-Cooled Condenser Removal and Replacement of Remote Air-Cooled Condenser Page Adjustment of Water Regulating Valve water-cooled model Removal and Replacement of Thermistor Removal and Replacement of Inlet Water Valve Removal and Replacement of Pump Motor Removal and Replacement of Control Board Cleaning and Sanitizing Instructions VI. Cleaning and MaintenanceCleaning Procedure Sanitizing Procedure Following Cleaning Procedure Preparing the Icemaker for Long Storage MaintenanceDrain the water tank