Hoshizaki KM-320MAH, KM-320MWH User Manual

HoshizakiHoshizaki America, Inc.

Modular Crescent Cuber

Models

KM-320MAH

KM-320MWH

“A Superior Degree

of Reliability”

www.hoshizaki.com

SERVICE MANUAL

Number: 73132

Issued: 1-24-2006

Revised: 11-30-2006

IMPORTANT

Only qualified service technicians should attempt to service or maintain this icemaker. No such service or maintenance should be undertaken until the technician has thoroughly read this Service Manual.

HOSHIZAKI provides this manual primarily to assist qualified service technicians in the service and maintenance of the icemaker.

Should the reader have any questions or concerns which have not been satisfactorily addressed, please call or write to the HOSHIZAKI Technical Support Department for assistance.

HOSHIZAKI AMERICA, INC.

618 Highway 74 South

Peachtree City, GA 30269

Attn: HOSHIZAKI Technical Support Department

Phone: [phone] Technical Service

[phone]

Fax: [phone]

[phone]

Web Site: www.hoshizaki.com

NOTE: To expedite assistance, all correspondence/communication MUST include the following information:

•Model Number

•Serial Number

•Complete and detailed explanation of the problem

Please review this manual. It should be read carefully before the icemaker is serviced or maintenance operations are performed. Only qualified service technicians should service and maintain the icemaker. This manual should be made available to the technician prior to service or maintenance.

CONTENTS
I. Specifications......................................................................................................................	5
A. KM-320MAH (air-cooled)...............................................................................................	5
B. KM-320MWH (water-cooled).........................................................................................	6
II. General Information............................................................................................................	7
A. Construction..................................................................................................................	7
1. KM-320MAH (air-cooled).........................................................................................	7
2. KM-320MWH (water-cooled)....................................................................................	8
B. Controller Board.............................................................................................................	9
1. Solid-State Control...................................................................................................	9
2. Controller Board.......................................................................................................	9
3. Sequence...............................................................................................................	13
4. Controls and Adjustments .....................................................................................	16
5. Checking the Controller Board...............................................................................	19
III. Technical Information.......................................................................................................	21
A. Water Circuit and Refrigerant Circuit...........................................................................	21
1. KM-320MAH...........................................................................................................	21
2. KM-320MWH..........................................................................................................	22
B. Wiring Diagram............................................................................................................	23
1. KM-320MAH, KM-320MWH...................................................................................	23
C. Timing Chart ...............................................................................................................	24
D. Performance Data........................................................................................................	26
1. KM-320MAH...........................................................................................................	26
2. KM-320MWH..........................................................................................................	27
IV. Service Diagnosis............................................................................................................	28
A. No Ice Production........................................................................................................	28
B. Evaporator is Frozen Up..............................................................................................	31
C. Low Ice Production......................................................................................................	33
D. Abnormal Ice...............................................................................................................	33
E. Other............................................................................................................................	33
V. Removal and Replacement of Components.....................................................................	34
A. Service for Refrigerant Lines.......................................................................................	34
1. Refrigerant Recovery.............................................................................................	34
2. Evacuation and Recharge (R-404A)......................................................................	34
B. Brazing.........................................................................................................................	35
C. Removal and Replacement of Compressor.................................................................	36
D. Removal and Replacement of Drier.............................................................................	37
E. Removal and Replacement of Expansion Valve..........................................................	37
F. Removal and Replacement of Hot Gas Valve and Line Valve......................................	38
G. Removal and Replacement of Evaporator...................................................................	39
H. Removal and Replacement of Thermistor...................................................................	40
I. Removal and Replacement of Fan Motor......................................................................	41
J. Removal and Replacement of Water Valve..................................................................	41

K. Removal and Replacement of Pump Motor.................................................................	42
L. Removal and Replacement of Spray Tubes.................................................................	42
M. Removal and Replacement of Water Regulating Valve – Water Cooled Model Only.. 43
N. Adjustment Of Water Regulating Valve – Water-Cooled Model Only...........................	44
VI. Cleaning and Maintenance Instructions..........................................................................	45
A. Preparing the Icemaker for Long Storage....................................................................	45
B. Cleaning and Sanitizing Instructions............................................................................	47
1. Cleaning Procedure...............................................................................................	48
2. Sanitizing Procedure - Following Cleaning Procedure...........................................	49
C. Maintenance................................................................................................................	50

I. Specifications

A. KM-320MAH (air-cooled)

AC SUPPLY VOLTAGE	115/60/1
AMPERAGE	9.7 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY	20 A
MAXIMUM FUSE SIZE	20 A
APPROXIMATE ICE PRODUCTION	Ambient	WATER TEMP. (°F)
PER 24 HR.	Temp.(°F)	50		70		90
lbs./day ( kg/day )	70	*325 (147)		311 (141)		287 (130)
Reference without *marks	80	315 (143)		293 (133)		265 (120)
	90	311 (141)		*278 (126)		251 (114)
SHAPE OF ICE	100	304 (138)		272 (123)		226 (103)
	Crescent Cube
ICE PRODUCTION PER CYCLE	7.2 lbs. (3.3 kg) 360 pcs.
APPROXIMATE STORAGE CAPACITY	N/A
ELECTRIC & WATER CONSUMPTION	90/70°F			70/50°F
ELECTRIC W (kWH/100 lbs.)	800(6.9)			750(5.5)
WATER gal./24HR (gal./100 lbs.)	51(18.4)			117(35.9)
EXTERIOR DIMENSIONS (WxDxH)	22" x 27-3/8" x 30-5/16" (560 x 695 x 770 mm)
EXTERIOR FINISH	Stainless Steel, Galvanized Steel (Rear)
WEIGHT	Net 123 lbs. (56 kg), Shipping			153 lbs. (70 kg)
CONNECTIONS - ELECTRIC	Permanent - Connection
- WATER SUPPLY	Inlet	1/2" FPT
- DRAIN	Outlet	3/4" FPT
		3/8" OD Tube
CUBE CONTROL SYSTEM	Float Switch
HARVESTING CONTROL SYSTEM	Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL	Timer Controlled. Overflow Pipe
COOLING WATER CONTROL	N/A
BIN CONTROL SYSTEM	Thermostat
COMPRESSOR	Hermetic, Model ASE32C3E-CAA
CONDENSER	Air-Cooled , Fin and tube type
EVAPORATOR	Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL	Thermostatic Expansion Valve
REFRIGERANT CHARGE	R-404A, 1 lb. 4.3 oz. (575g)
DESIGN PRESSURE	High 467PSIG, Low 210PSIG
P.C. BOARD CIRCUIT PROTECTION	High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION	Auto-reset Overload Protector ( Internal )
REFRIGERANT CIRCUIT PROTECTION	Auto-reset High Pressure Control Switch
LOW WATER PROTECTION	Float Switch
ACCESSORIES -SUPPLIED	N/A
-REQUIRED	Ice Storage Bin
OPERATING CONDITIONS	VOLTAGE RANGE					104 - 127 V
	AMBIENT TEMP.					45 -100° F
	WATER SUPPLY TEMP.					45 - 90° F
	WATER SUPPLY PRESSURE					10 - 113 PSIG

Note: We reserve the right to make changes in specifications and design without prior notice.

B. KM-320MWH (water-cooled)

AC SUPPLY VOLTAGE	115/60/1
AMPERAGE	8.2 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY	20 A
MAXIMUM FUSE SIZE	20 A
APPROXIMATE ICE PRODUCTION	Ambient	WATER TEMP. (°F)
PER 24 HR.	Temp.(°F)	50		70		90
lbs./day ( kg/day )	70	*352 (160)		348 (158)		324 (147)
Reference without *marks	80	349 (158)		342 (155)		309 (140)
	90	348 (158)		*337 (153)		308 (140)
SHAPE OF ICE	100	337 (153)		330 (150)		281 (127)
	Crescent Cube
ICE PRODUCTION PER CYCLE	7.2 lbs. (3.3 kg) 360 pcs.
APPROXIMATE STORAGE CAPACITY	N/A
ELECTRIC & WATER CONSUMPTION	90/70°F			70/50°F
ELECTRIC W (kWH/100 lbs.)	730(5.2)			730(5.0)
WATER gal./24HR (gal./100 lbs.)	57(16.8)			103(29.4)
WATER COOLED CONDENSER	528(157)			327(93)
gal./24HR (gal./100 lbs.)
EXTERIOR DIMENSIONS (WxDxH)	22" x 27-3/8" x 30-5/16" (560 x 695 x 770 mm)
EXTERIOR FINISH	Stainless Steel, Galvanized Steel (Rear)
WEIGHT	Net 123 lbs. (56 kg), Shipping			153 lbs. (70 kg)
CONNECTIONS - ELECTRIC	Permanent - Connection
- WATER SUPPLY	Inlet	1/2" FPT
- DRAIN	Outlet	3/4" FPT
		3/8" OD Tube
CUBE CONTROL SYSTEM	Float Switch
HARVESTING CONTROL SYSTEM	Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL	Timer Controlled. Overflow Pipe
COOLING WATER CONTROL	Pressure Regulator
BIN CONTROL SYSTEM	Thermostat
COMPRESSOR	Hermetic, Model ASE32C3E-CAA
CONDENSER	Water-cooled, Tube in tube type
EVAPORATOR	Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL	Thermostatic Expansion Valve
REFRIGERANT CHARGE	R-404A, 1 lb. 0.8 oz. (486g)
DESIGN PRESSURE	High 427PSIG, Low 210PSIG
P.C. BOARD CIRCUIT PROTECTION	High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION	Auto-reset Overload Protector ( Internal )
REFRIGERANT CIRCUIT PROTECTION	Auto-reset High Pressure Control Switch
LOW WATER PROTECTION	Float Switch
ACCESSORIES -SUPPLIED	N/A
-REQUIRED	Ice Storage Bin
OPERATING CONDITIONS	VOLTAGE RANGE					104 - 127 V
	AMBIENT TEMP.					45 -100° F
	WATER SUPPLY TEMP.					45 - 90° F
	WATER SUPPLY PRESSURE					10 - 113 PSIG

Note: We reserve the right to make changes in specifications and design without prior notice.

II. General Information

A.Construction

1.KM-320MAH (air-cooled)

Evaporator

Cleaning Valve

Bin Control

Thermostat

Float Switch

Water Pump

Compressor

Spray Tubes	Expansion Valve
	Control Switch

Water Supply Inlet

Hot Gas Valve

Condenser

Fan Motor

Drier

Control Box

(shown transparent to allow view of other components)

2. KM-320MWH (water-cooled)

Spray Tubes	Expansion Valve
	Control Switch
	Water Supply Inlet
	Hot Gas Valve

Evaporator

Water Regulator

Cleaning Valve

Condenser

Bin Control

Thermostat

Float Switch

Water Pump

Drier Compressor

Control Box

(shown transparent to allow view of other components)

B. Controller Board

1.Solid-State Control

•A HOSHIZAKI exclusive solid-state control is employed in KM-320MAH and

KM 320MWH Modular Crescent Cubers.

•A printed circuit board (hereafter called "controller board") includes a stable and high quality control system.

•All models are pretested and factory-adjusted.

2.Controller Board

CAUTION

1.Fragile, handle very carefully.

2.A controller board contains integrated circuits, which are susceptible to failure due to static discharge. It is especially important to touch the metal part of the unit when handling or replacing the board.

3.Do not touch the electronic devices on the board or the back of the board to prevent damage to the board.

4.Do not change wiring and connections. Do not misconnect K3, K4 and K5, because the same connector is used for the thermistor and float switch. K4 is not connected.

5.Always replace the whole board assembly when it goes bad.

6.Do not short out power supply to test for voltage.

	Controller Board
Part Number	Type
2A1410-01	HOS-001A (Control Products - 10 Pin)

Features of Control Products "E" Controller Board

a) Maximum Water Supply Period - 6 minutes

Water solenoid valve opening, in the defrost (harvest) cycle, is limited by the defrost timer. The water valve cannot remain open longer than the maximum period. The water valve can close in less than six minutes if the defrost cycle is completed.

b) 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 (9°C) 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.

c) High Temperature Safety - 127 ± 7°F (53 ± 4°C)

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 (9°C) 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 (53 ± 4°C) the thermistor operates the high temperature safety.

This high temperature safety shuts down the circuit and the icemaker automatically stops.

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.

d) 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.

For water-cooled model, if the water is shut off, the unit is protected by the high pressure switch.

e) 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.

f) 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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The green LEDs 1-4 represent the corresponding relays and energize and sequence 5 seconds from initial startup as follows:

Sequence Step	LED			Time LEDs are Lit
		Min.		Max.	Avg.
1 Minute Fill Cycle	4				60 seconds
Harvest Cycle	1, 4, and 2	2 minutes		20 minutes	3 to 5 minutes
Freeze Cycle	1	5 minutes		60 minutes	30 to 35 minutes
Reverse Pump Out	1, 3, and 2	10 seconds		20 seconds	factory setting
{Led 1 – Comp; Led 2 - HGV/CFM;			Led 3 – PM;		Led 4 - WV}

The built in safeties shut down the unit and have alarms as follows:

	No. of Beeps	Type of Alarm	Notes
	(every 3 sec.)
	1	High Evaporator Temp.	Check for defrost problem (stuck HGV
		(temperature > 127°F)	or relay), hot water entering unit, stuck
		(53°C)	headmaster, or shorted thermistor.
	2	Defrost Backup Timer	Orange LED marked H TIMER lights up.
		(defrost > 20 min.)	Check for open thermistor, HGV not
			opening, TXV leaking by, low charge, or
			inefficient compressor.
	3	Freeze Backup Timer	Yellow LED marked F TIMER lights up.
		(freeze > 60 min.)	Check for F/S stuck closed (up), WV
			leaking by, HGV leaking by, TXV not
			feeding properly, low charge, or inefficient
			compressor.

To manually reset the above safeties, press the white alarm reset button with the power supply on.

6	Low Voltage
	(92Vac or less)
7	High Voltage	Red LED will turn off if voltage protection
	(control voltage	operates.
	> 147Vac ±5%)	The voltage safety automatically resets
		when voltage is corrected.

The output test switch "S3" provides a relay sequence test. With power OFF, place S3

ON and switch power to ICE. The correct lighting sequence should be none, 2, 3, 4, 1, & 4, normal sequence every 5 seconds. S3 should remain in the "OFF" position for normal operation.

11

The application switch located between relay X3 & X4 must be set to match the original board application. Place this switch in the ALP position if there is no white wire supplied to the K1 connector. If there is a white wire, place the switch in the C position. If this switch is placed in the wrong position either the compressor contactor will remain energized with the control switch OFF or the unit will not start.

The dip switches should be adjusted per the adjustment chart published in the Tech Specs book. 7 & 8 must remain in the OFF position.

(Control Products HOS-001A Board)

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3. Sequence

1st Cycle

1.Unit energized and control switch to "ICE" position. Water supply cycle starts.

2.After 1 minute, defrost cycle starts.

3.Thermistor reads 48°F (9°C). Defrost timer starts counting.

Water Valve	Water Valve
	Hot Gas Valve

Defrost

Cycle

Freeze

Cycle

Pump, Fan &

Line Valve

Timer

Defrost

IMPORTANT

Water valve opening is limited to 6 minutes.

5.After the first 5 minutes in freeze cycle. Ready to complete freeze cycle when float switch circuit opens.

IMPORTANT

Board never accepts freeze completion signal within the first 5 minutes in freeze cycle.

4.Defrost timer stops counting. Defrost cycle is completed and freeze cycle starts.

IMPORTANT

1.Board never accepts defrost completion signal within the first 2 minutes in defrost cycle.

2.Defrost cycle time is limited to 20 minutes even if defrost timer does not stop counting.

13

2nd Cycle and after with pump drain

IMPORTANT

Freeze cycle time is limited by the freeze timer factory setting even if the float switch does not open.

1.Float switch opens and signals to complete freeze cycle. Drain timer starts counting.

2.Drain timer stops counting. Pump drain is completed.

Drain Pump

Hot Gas Valve

Defrost

Cycle

Freeze

Cycle

Pump, Fan &

Line Valve

Valve

Water

3.Thermistor reads 48°F (9°C). Defrost timer starts counting.

Defrost	Timer
			IMPORTANT
		Water valve opening is
		limited to 6 minutes.

5.After the first 5 minutes in freeze cycle. Ready to complete freeze cycle when float switch circuit opens.

4.Defrost timer stops counting. Defrost cycle is completed and freeze cycle starts.

IMPORTANT

Board never accepts freeze completion signal within the first 5 minutes in freeze cycle.

IMPORTANT

1.Board never accepts defrost completion signal within the first 2 minutes in defrost cycle.

2.Defrost cycle time is limited to 20 minutes even if defrost timer does not stop counting.

14

2nd Cycle and after with no pump drain

IMPORTANT

Freeze cycle time is limited by the freeze timer factory setting even if the float switch does not open.

1.Float switch opens and signals to complete freeze cycle.

2.Thermistor reads 48°F (9°C). Defrost timer starts counting.

Water Valve

Hot Gas Valve

Defrost

Cycle

Freeze

Cycle

Pump, Fan &

Line Valve

Timer

Defrost

IMPORTANT

Water valve opening is limited to 6 minutes.

4.After the first 5 minutes in freeze cycle. Ready to complete freeze cycle when float switch circuit opens.

IMPORTANT

Board never accepts freeze completion signal within the first 5 minutes in freeze cycle.

3.Defrost timer stops counting. Defrost cycle is completed and freeze cycle starts.

IMPORTANT

1.Board never accepts defrost completion signal within the first 2 minutes in defrost cycle.

2.Defrost cycle time is limited to 20 minutes even if defrost timer does not stop counting.

15