Hoshizaki KM-901MWH, KM-901MAH, KM-901MRH/3 LED Lights and Audible Alarm Safeties, Sequence Step

Page 30

f) LED Lights and Audible Alarm Safeties

(1) "E" Control Board: Auxiliary Code T-0, U-0

At startup, a 5-second delay occurs while the control board conducts an internal timer check. A beep occurs when power is turned off. The red LED indicates proper control voltage and remains on unless a control voltage problem occurs. The green LEDs

1 through 4 energize and sequence from initial startup as listed in the table below. Note that the order of the LEDs from the outer edge of the control board is 1, 4, 3, 2.

For details, see "II.B. Sequence of Operation."

	Sequence Step	LED	Energized		Time LEDs are On
	Sequence Step	LED	Components	Min.	Max.	Avg.
			Components	Min.	Max.	Avg.
	1-Minute Fill Cycle	4	WV			1 minute
	Harvest Cycle	1, 4, 2	Comp, FMR, WV,	2 minutes	20 minutes	3 to 5 minutes
			HGV
	Freeze Cycle	1	Comp, FM/FMR, PM,	5 minutes	freeze timer 30 to 35 minutes
			LLV		setting
	Pump-Out Cycle	1, 4*, 3, 2	Comp, FMR, WV*,	10 seconds	20 seconds	*pump-out timer setting
			PM, HGV

The built-in safeties shut down the unit and have alarms as listed below.

	No. of Beeps	Type of Alarm	Notes
	(every 3 sec.)	Type of Alarm	Notes
	(every 3 sec.)
	1	High Evaporator Temp.	Check for harvest problem (stuck HGV or relay), hot
		(temperature > 127°F)	water entering unit, stuck HM, or shorted thermistor.
		(53°C)
	2	Harvest Backup Timer	Orange "H TIMER" LED on.
		(harvest > 20 min. for two cycles	Check for open thermistor, HGV not opening, TXV or
		in a row)	LLV leaking by, low charge, inefficient Comp, or WRV
			leaking by.
	3	Freeze Timer	Yellow "F TIMER" LED on.
		(freeze > freeze timer setting for	Check for F/S stuck closed (up), WV leaking by, HGV
		two cycles in a row)	leaking by, PM not pumping, TXV not feeding properly,
			LLV not opening, low charge, HM not bypassing, or
			inefficient Comp.
	To reset the above safeties, press the "ALARM RESET" button with the power supply on.
	6	Low Voltage	Red LED turns off if voltage protection operates.
		(92Vac±5% or less)	The control voltage safeties automatically reset when
	7	High Voltage	voltage is corrected.
		(147Vac±5% or more)

Legend: Comp–compressor; FM–fan motor; FMR–fan motor-remote;

F/S–float switch; HGV–hot gas valve; HM–headmaster (C.P.R.); LLV–liquid line valve; PM–pump motor; TXV–thermostatic expansion valve; WRV–water regulating valve; WV–inlet water valve

30

Image 30

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