Hoshizaki KM-901MWH, KM-901MAH, KM-901MRH/3 service manual Abnormal Ice

Page 66

Problem	Possible Cause		Remedy

[1] Freeze cycle time is	n) Control Board	1. Float switch	1. Check and reconnect.
long. (continued)		connection loose (K5).

		2. Defective.	2. See "IV.B. Control Board
			Check."
[2] Harvest cycle time is	a) Water Supply	1. Water temperature too	1. Increase temperature.
long.		cold.
	b) Thermistor	1. Disconnected, loose,	1. Connect, secure, check.
		or defective.	See "V.L. Removal
			and Replacement of
			Thermistor" and "IV.E.
			Thermistor Check."

	c) Control Board	1. Not reading	1. Check and replace. See
		thermistor.	"IV.E. Thermistor Check."

		2. Sending voltage to	2. Check and replace. See
		liquid line valve (if	"IV.B. Control Board
		applicable) in harvest.	Check."

	d) Inlet Water Valve	1. Clogged.	1. Clean or replace.
	e) Evaporator	1. Scaled up.	1. Clean.

		2. Damaged.	2. Replace.

	f) Hot Gas Valve	1. Does not open, or	1. Check and replace.
		opens partially.

	g) Expansion Valve	1. Wide open in harvest.	1. Check and replace.

		2. Bulb loose.	2. Secure bulb.

	h) Water Regulating Valve	1. Open during harvest.	1. Adjust or replace. See
	(water-cooled model)		"V.J. Adjustment of Water
			Regulating Valve."

	i) Liquid Line Valve (if	1. Open during harvest	1. Check and replace.
	applicable)	cycle.

4. Abnormal Ice

Problem	Possible Cause		Remedy

[1] Small cubes.	a) Pump-Out Check Valve	1. Dirty or worn and	1. Clean or replace.
		leaking by.

	b) Ice Cube Guide	1. Out of position.	1. Place in position.
		Circulated water falls
		into bin.

	c) Water System	1. Water supply line too	1. Increase water line size.
		small; requires 3/8"
		OD line dedicated per
		machine.
		2. Water filter clogged or	2. Replace filter or install a
		flow rate too small.	higher flow rate filter.

	d) Inlet Water Valve	1. Dirty mesh filter or	1. Clean.
		orifice.

	e) Pump Motor	1. RPM too slow.	1. See chart 1.[5].

	f) Control Board	1. Defective.	1. See "IV.B. Control Board
			Check."

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Contents KM-901MAH KM-901MWH Hoshizaki AMERICA, INC Contents Page Page Indicates important information about the use and care Important Safety InformationSerious injury UnitSpecifications Icemaker 1a. KM-901MAH air-cooled Auxiliary Code T-0, U-01b. KM-901MAH air-cooled Auxiliary Code U-1 and Later 2a. KM-901MWH water-cooled Auxiliary Code T-0, U-0 Water Cooled Condenser2b. 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 Specifications Model URC-9FII. General Information Construction KM-901MAH air-cooledKM-901MWH water-cooled KM-901MRH/3 remote air-cooled Sequence of Operation Sequence Cycles and ShutdownControl Board Auxiliary Code T-0, U-0 Shutdown Control Board Auxiliary Code U-1 and LaterOFF Cycle at Shutdown Mechanical Bin Control Activation Cycle Control Board Sequence Flow ChartSequence Flow Chart Bin FullMinute Harvest Cycle Freeze Cycle Pump-Out Cycle Control Board Auxiliary Code U-1Later Fill CycleControl Board Control Board Layout Control BoardPart Number 2A3792-01 Low Water Safety Harvest Backup Timer and Freeze TimerHigh Temperature Safety Maximum Water Supply Period 6 minutesSequence Step LED Lights and Audible Alarm SafetiesNo. of Beeps Type of Alarm Every 3 sec Energized Time LEDs are On Components Min Max AvgControl Board Auxiliary Code U-1 and Later Harvest Timer S4 dip switch 1 Controls and AdjustmentsDefault Dip Switch Settings S4 Dip Switch S4 Dip Switch NoPump-Out Timer S4 dip switch 3 Pump-Out Frequency Control S4 dip switch 5S4 Dip Switch Setting Time seconds Inlet Control Board S4 Dip Switch Setting Bin Control Bin Control Selector/Harvest Pump Timer S4 dip switchFactory Use S4 dip switch Control Board S4 Dip Switch Setting Pump Motor Time secondsRefill Counter S5 dip switch 2 through 5 G Control Board Freeze Timer S4 dip switch 9Float Switch Control S5 dip switch 1 G Control Board S4 Dip Switch Setting Time MinutesBin Control Float SwitchControl Switch ThermistorWater Pump Switch Discharge Line Wiring Diagrams ModelCooled-AirWater-Cooled Model PressureHigh* SwitchKM-901MAH air-cooled and KM-901MWH water-cooled PressureSwitch KM-901MRH remote air-cooledHigh KM-901MRH3 remote air-cooled Switch Cooled-WaterModel Cooled-AirModel High* PressureHigh Pressure Switch SwitchPressure Performance Data 1480 912835 1570KM-901MRH remote air-cooled KM-901MRH3 remote air-cooled IV. Service Diagnosis Diagnostic ProcedurePage OFF Control Board Check Shutdown Thermostatic Bin Control Auxiliary Code T-0, U-0Bin Control Check Control Correct LED Board Lighting SequenceMechanical Bin Control Check Mechanical Bin Control Cleaning Float Switch Check and Cleaning Float Switch CheckFloat Switch Cleaning Thermistor Check Diagnostic Charts Problem Possible Cause RemedyNo Ice Production Problem Possible Cause Remedy Problem Possible Cause Remedy Evaporator is Frozen Up Problem Possible Cause Remedy Low Ice Production Abnormal Ice Other Removal and Replacement of Components Service for Refrigerant LinesRefrigerant Recovery Brazing Evacuation and Recharge R-404ARemoval 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 VI. Cleaning and Maintenance Cleaning and Sanitizing InstructionsCleaning Procedure Sanitizing Procedure Following Cleaning Procedure Maintenance Preparing the Icemaker for Long StorageDrain the water tank