Hoshizaki Modular Crescent Cuber Km 501Mwh Users Manual

KM-501MRH KM-501MRH_sm

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1

Hoshizaki

“A Superior Degree

of Reliability”

www.hoshizaki.com

Models

KM-501MAH

KM-501MWH

KM-501MRH

Modular Crescent Cuber

Hoshizaki America, Inc.

SERVICE MANUAL

™

Number: 73137

Issued: 10-16-2006

Revised: 3-27-2007

2

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: 1-800-233-1940 Technical Service

(770) 487-2331

Fax: 1-800-843-1056

(770) 487-3360

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

3

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. Icemaker ....................................................................................................................... 5

1. KM-501MAH (air-cooled) ......................................................................................... 5

2. KM-501MWH (water-cooled) ................................................................................... 6

3. KM-501MRH (remote air-cooled) ............................................................................ 7

B. Condensing Unit ............................................................................................................ 8

1. URC-6F ................................................................................................................... 8

II. General Information ......................................................................................................... 10

A. Construction ................................................................................................................ 10

1. KM-501MAH (air-cooled) ....................................................................................... 10

2. KM-501MWH (water-cooled) ................................................................................. 11

3. KM-501MRH (remote air-cooled) .......................................................................... 12

B. Sequence of Operation ............................................................................................... 13

1. One Minute Fill Cycle ............................................................................................ 13

2. Initial Harvest Cycle .............................................................................................. 13

3. Freeze Cycle ......................................................................................................... 13

4. Pump-Out Cycle ................................................................................................... 13

5. Normal Harvest Cycle .......................................................................................... 13

C. Control Board .............................................................................................................. 15

1. Control Board Layout ............................................................................................. 16

2. Features ................................................................................................................ 17

a) Maximum Water Supply Period – 6 minutes ....................................................... 17

b) Harvest Backup Timer and Freeze Timer ........................................................... 17

c) High Temperature Safety .................................................................................... 17

d) Low Water Safety ............................................................................................... 17

e) High Voltage and Low Voltage Cut-outs ............................................................. 17

f) LED Lights and Audible Alarm Safeties ............................................................... 18

3. Controls and Adjustments ..................................................................................... 19

a) Default Dip Switch Settings ................................................................................ 19

b) Harvest Control – Thermistor ............................................................................. 19

c) Harvest Timer (dip switch 1 & 2) ......................................................................... 20

d) Pump-Out Timer (dip switch 3 & 4)..................................................................... 20

e) Pump-Out Frequency Control (dip switch 5 & 6) ................................................ 21

f) Freeze Timer (dip switch 9 & 10) ......................................................................... 21

g) Bin Control .......................................................................................................... 21

4. Control Board Check Procedure ............................................................................ 22

5. Control Board Replacement .................................................................................. 22

4

III. Technical Information ...................................................................................................... 23

A. Water Circuit and Refrigeration Circuit ........................................................................ 23

1. KM-501MAH (air-cooled) ....................................................................................... 23

2. KM-501MWH (water-cooled) ................................................................................. 24

3. KM-501MRH (remote air-cooled) .......................................................................... 25

B. Wiring Diagrams .......................................................................................................... 26

1. KM-501MAH (air-cooled) and KM-501MWH (water-cooled) ................................. 26

2. KM-501MRH (remote air-cooled) .......................................................................... 27

C. Timing Chart ............................................................................................................... 28

D. Performance Data ....................................................................................................... 30

1. KM-501MAH (air-cooled) ....................................................................................... 30

2. KM-501MWH (water-cooled) ................................................................................. 31

3. KM-501MRH (remote air-cooled) .......................................................................... 32

IV. Service Diagnosis ........................................................................................................... 33

A. 10-Minute KM Diagnostic Procedure ......................................................................... 33

B. Diagnostic Charts ........................................................................................................ 34

1. No Ice Production .................................................................................................. 34

2. Evaporator is Frozen Up ........................................................................................ 38

3. Low Ice Production ................................................................................................ 39

4. Abnormal Ice ......................................................................................................... 39

5. Other ...................................................................................................................... 39

V. Removal and Replacement of Components .................................................................... 41

A. Service for Refrigerant Lines ...................................................................................... 41

1. Refrigerant Recovery ............................................................................................. 41

2. Evacuation and Recharge (R-404A) ...................................................................... 41

B. Brazing ........................................................................................................................ 42

C. Removal and Replacement of Compressor ................................................................ 42

D. Removal and Replacement of Drier ............................................................................ 43

E. Removal and Replacement of Expansion Valve .......................................................... 44

F. Removal and Replacement of Hot Gas Valve and Line Valve ..................................... 44

G. Removal and Replacement of Evaporator .................................................................. 45

H. Removal and Replacement of Water Regulating Valve - Water Cooled Model Only ... 46

I. Adjustment of Water Regulating Valve - Water-Cooled Model Only ............................. 46

J. Removal and Replacement of Headmaster (Condensing Pressure Regulator - C.P.R.)

- Remote Air-Cooled Model Only .............................................................................. 47

K. Removal and Replacement of Thermistor ................................................................... 48

L. Removal and Replacement of Fan Motor .................................................................... 49

M. Removal and Replacement of Inlet Water Valve ......................................................... 49

N. Removal and Replacement of Pump Motor ................................................................ 49

O. Removal and Replacement of Spray Tubes ................................................................ 50

VI. Cleaning and Maintenance Instructions ......................................................................... 51

A. Cleaning and Sanitizing Procedures ........................................................................... 51

1. Cleaning Procedure ............................................................................................... 52

2. Sanitizing Procedure - Following Cleaning Procedure .......................................... 53

B. Maintenance ................................................................................................................ 53

C. Preparing the Icemaker for Long Storage ................................................................... 54

5

AC SUPPLY VOLTAGE 115/60/1

AMPERAGE 13 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 *498 (226) 474 (215) 433 (197)

Reference without *marks 80 480 (218) 442 (201) 397 (180)

90 474 (215) *416 (189) 372 (169)

100 463 (210) 406 (184) 332 (150)

SHAPE OF ICE Crescent Cube

ICE PRODUCTION PER CYCLE 9.5 lbs. (4.3 kg) 480 pcs.

APPROXIMATE STORAGE CAPACITY N/A

ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F

ELECTRIC W (kWH/100 lbs.) 1210(7.0) 1140(5.5)

WATER gal./24HR (gal./100 lbs.) 89(21.3) 245(49.1)

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 151 lbs. (69 kg), Shipping 175 lbs. (80 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 AKA9455ZXA

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. 10 oz. (735g)

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

I. Specifications

A. Icemaker

1. KM-501MAH (air-cooled)

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

notice.

6

2. KM-501MWH (water-cooled)

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

notice.

AC SUPPLY VOLTAGE 115/60/1

AMPERAGE 10 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 *498 (226) 495 (224) 465 (211)

Reference without *marks 80 496 (225) 491 (223) 447 (203)

90 495 (224) *488 (221) 449 (204)

100 480 (218) 479 (217) 413 (187)

SHAPE OF ICE Crescent Cube

ICE PRODUCTION PER CYCLE 9.5 lbs. (4.3 kg) 480 pcs.

APPROXIMATE STORAGE CAPACITY N/A

ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F

ELECTRIC W (kWH/100 lbs.) 1080(5.3) 1070(5.2)

WATER gal./24HR (gal./100 lbs.) 101(20.8) 177(35.6)

WATER COOLED CONDENSER 670(137) 390(78)

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 151 lbs. (69 kg), Shipping 175 lbs. (80 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 AKA9455ZXA

CONDENSER Water-cooled, Tube in tube type

EVAPORATOR Vertical type, Stainless Steel and Copper

REFRIGERANT CONTROL Thermostatic Expansion Valve

REFRIGERANT CHARGE R-404A, 15 oz. (425g)

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

7

3. KM-501MRH (remote air-cooled)

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

notice.

AC SUPPLY VOLTAGE 115/60/1

AMPERAGE 15 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 *482 (219) 475 (215) 437 (198)

Reference without *marks 80 476 (216) 465 (211) 412 (187)

90 475 (215) *457 (207) 410 (186)

100 458 (208) 446 (202) 367 (166)

SHAPE OF ICE Crescent Cube

ICE PRODUCTION PER CYCLE 9.5 lbs. (4.3 kg ) 480 pcs.

APPROXIMATE STORAGE CAPACITY N/A

ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F

ELECTRIC W (kWH/100 lbs.) 1260(6.6) 1220(6.1)

WATER gal./24HR (gal./100 lbs.) 90(19.6) 182(37.8)

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 151 lbs. ( 69 kg ), Shipping 175 lbs. ( 80 kg )

CONNECTIONS - ELECTRIC Permanent - Connection

- WATER SUPPLY Inlet 1/2" FPT

- DRAIN Outlet 3/4" FPT

3/8" OD Pipe

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 AKA9455ZXA

CONDENSER Air-cooled Remote, Condenser Unit URC 6F

EVAPORATOR Vertical type, Stainless Steel and Copper

REFRIGERANT CONTROL Thermostatic Expansion Valve

Condensing Pressure Regulator on URC-6F

REFRIGERANT CHARGE R-404A, 4 lbs. 0 oz. ( 1800 g )

( Icemaker 2 lbs. 1.5 oz. Cond. Unit 1 lb. 14 oz. )

DESIGN PRESSURE High 467 PSIG, Low 230 PSIG

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, Remote Condenser Unit

OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V

AMBIENT TEMP. 45 -100° F

WATER SUPPLY TEMP. 45 - 90° F

WATER SUPPLY PRESSURE 10 - 113 PSIG

8

B. Condensing Unit

1. URC-6F

24"

(610 mm.)

23-1/32"

(585 mm.)

19-11/16"

(500 mm.)

18-1/8"

(460 mm.)

20-15/32"

(520 mm.)

21-15/16"

(557 mm.)

7/8" DIA. HOLE

(23 mm. DIA.)

6-5/16"

(160 mm.)

2-15/16"

(75 mm.)

18-1/8"

(460 mm.)

6/16" x 3/4" (10 mm. x 20 mm.)

4 x 2 (SLOTTED HOLES)

17-1/8"

(435 mm.)

14-9/16"

(370 mm.)

14-1/8"

(358 mm.)

14-15/16"

(380 mm.)

15-11/16"

(398 mm.)

17-7/8"

(454 mm.)

2-1/2"

(63 mm.)

14-15/16"

(380 mm.)

9

SPECIFICATIONS

MODEL: URC-6F

Galvanized Steel

21-15/16" x 15-11/16" x 17-7/8"

(557 x 398 x 453.8 mm.)

R404A 1 lb. 2 oz. (505 g)

Net 61 lbs. (28 kg)

Shipping 68 lbs. (31 kg)

One Shot Couplings (Parker)

Permanent Connection

Air-cooled

Condensing Pressure Regulator

Min. -20°F - Max. +122°F

(-29°C to +50°C)

Outdoor use

EXTERIOR

DIMENSIONS (W x D x H)

REFRIGERANT CHARGE

WEIGHT

CONNECTIONS

REFRIGERANT

ELECTRICAL

CONDENSER

HEAD PRESSURE CONTROL

AMBIENT CONDITION

10

II. General Information

A. Construction

1. KM-501MAH (air-cooled)

Spray Tubes Water Supply Inlet

Control Switch

Condenser

Hot Gas Valve

Expansion Valve Fan Motor

Condenser

Compressor

Drier

Float Switch

Control Box

Water Pump

Bin Control Thermostat

11

2. KM-501MWH (water-cooled)

Spray Tubes Water Supply Inlet

Control Switch

Water Regulator

Expansion Valve Hot Gas Valve

Compressor

Float Switch Drier

Water Pump Control Box

Bin Control Thermostat

12

3. KM-501MRH (remote air-cooled)

Spray Tubes Water Supply Inlet

Control Switch

Junction Box

Expansion Valve Receiver Tank

Compressor

Float Switch Drier

Water Pump Hot Gas Valve

Line Valve

Control Box

Bin Control Thermostat

13

B. Sequence of Operation

The steps in the sequence are as outlined below. When power is supplied, a 5 second

delay occurs at startup. Note that the order of the LEDs from the outer edge of the board is

1, 4, 3, 2.

1. One Minute Fill Cycle

LED 4 is on. WV opens and the fill period begins. After 1 minute, the board checks for

a closed F/S. If F/S is closed, the harvest cycle begins. If not, WV will remain energized

through additional 1 minute cycles until water enters the sump and F/S closes. This serves

as a low water safety to protect the water pump.

2. Initial Harvest Cycle

LEDs 1, 4, and 2 are on. WV remains open, Comp and FMR energize, HGV opens,

and harvest begins. As the evaporator warms, the thermistor located on the suction line

checks for a 48°F (9°C) temperature. When 48°F (9°C) is reached, a 3.9 kΩ signal turns

the harvest over to the adjustable harvest timer which is factory set for normal conditions.

The timer has settings of 60, 90, 120, and 180 seconds (dip switch 1 & 2). The water valve

is open during harvest for a maximum of 6 minutes or the length of harvest, whichever is

shorter. When the harvest timer completes its count down, the harvest cycle is complete

and the freeze cycle starts. The minimum total time allowed by the board for a complete

harvest cycle is 2 minutes.

3. Freeze Cycle

LED 1 is on. Comp and FMR continue to run, PM and FMS energize, LLV opens, HGV

and WV close and the freeze cycle starts. For the first 5 minutes the control board will not

accept a signal from F/S. This 5 minute minimum freeze acts as a short cycle protection. At

the end of 5 minutes, F/S assumes control. As ice builds on the evaporator the water level

in the sump lowers. The freeze continues until F/S opens and terminates ice production.

4. Pump-Out Cycle

LEDs 1, 3, and 2 are on. Comp and FMR continue to run, HGV opens, LLV closes, and

FMS deenergizes. PM stops for 2 seconds and reverses, taking water from the bottom of

the sump and forcing pressure against the check valve seat allowing water to go through

the check valve and down the drain. At the same time water flows through the small tube

to power flush the F/S. When the pump-out timer stops counting, the pump out is complete.

Pump out always occurs on the 2nd harvest after startup. Then, depending on the control

board setting, pump out occurs every cycle, or every 2nd, 5th or 10th cycle (dip switch 5 &

6).

5. Normal Harvest Cycle

LEDs 1, 4, and 2 are on. Comp and FMR continue to run, HGV remains open and WV

opens. As the evaporator warms, the thermistor reaches 48°F (9°C). The control board

then receives the thermistor's 3.9 kΩ signal and starts the harvest timer. The water valve

is open during harvest for a maximum of 6 minutes or the length of harvest, whichever is

shorter. When the harvest timer completes its count down, the harvest cycle is complete

and the next freeze cycle starts. The unit continues to cycle through 3, 4 and 5 sequence

until the bin control senses ice and shuts the unit down.

Legend: Comp–compressor; FMR–remote fan motor; FMS–self-contained fan motor;

F/S–float switch; HGV–hot gas valve; LLV–Liquid Line Valve; PM–pump motor;

WV–inlet water valve

14

KM-501MAH, KM-501MWH, KM-501MRH Sequence Flow Chart and Component Operation

1. One Minute

Fill Cycle

2. Harvest Cycle 3. Freeze Cycle

4. Pump-Out

Cycle

Cycle Steps

WV Energized

F/S open

F/S closed

Comp energized

HGV energized

FMR energized

WV continues

Thermistor temp

reaches 48°F (9°C)

(3.9 kΩ or less)

Harvest timer starts

F/S open

Comp continues

FMR continues

HGV de-energized

WV de-energized

PM energized

FMS energized

F/S closed

Freeze cycle

operation turned

over to F/S

Pump motor stops

for 2 sec. and then

reverses for 10/20 sec.

each 1, 2, 5, or 10 cycles.

Comp continues

FMR continues

HGV energized

FMS de-energized

F/S Check

F/S Check

• Maximum inlet water valve time: 6 minutes

• Maximum harvest time: 20 minutes

Thermistor in

control

1 to 3 minute timer

in control

• Minimum freeze time: 5 minutes

• Maximum freeze time: freeze timer setting

5 minute timer

in control

F/S in

control

Initial startup always

begins here

"E" board will have

5 second delay

If F/S is open, compressor stops and cycle returns to 1 minute fill

Legend: Comp - compressor FMS - self-contained fan motor HGV - hot gas valve WV - inlet water valve

FMR - remote fan motor F/S - float switch PM - pump motor

15

C. Control Board

• A HOSHIZAKI exclusive solid-state control is employed in KM-501MAH, KM-501MWH

and KM-501MRH Modular Crescent Cubers.

• All models are pretested and factory-adjusted.

CAUTION

1. Fragile, handle very carefully.

2. A control 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 if it goes bad.

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

16

Control Board

Part Number 2A1410-01 (factory); 2A1410-02 (service)

Type HOS-001A (Control Products - 10 Pin)

Control Products "E" Control Board

1. Control Board Layout

Output Test Switch

(used to test relays on board)

Connector K3

Harvest Control

(thermistor)

Connector K4

Open

(not connected)

Microprocessor

(board revision level

indicated by last 2

digits on label)

Connector K5

Float Switch

Part Number

Connector K1

Pins #1 through #10

#1, 9 Magnetic Contactor

#2 Hot Gas Valve

#3 Line Valve

Self-Contained Fan Motor (FMS)

#4 Pump Motor (icemaking)

#5 Pump Motor (drain)

#6 Water Valve

#7, 10 Power (line, bin control)

#8 Open

Switch for "C" board

and "ALPINE" board

(service boards only)

Alarm Reset Switch

Backup Freeze

Timer LED

Dip Switch

Backup Harvest

Timer LED

Alarm Buzzer

Power LED

(lights when

power is supplied

to the board)

Relay LEDs (4)

(indicate which

relays are energized

as listed below)

LED 2

Hot Gas Valve (HGV)

Self-Contained Fan

Motor (FMS) (FMS

off when LED on)

LED 3

Pump Motor (PM)

(on at pump out only)

LED 4

Water Valve (WV)

LED 1

Compressor (Comp)

Remote Fan Motor

(FMR)

Transformer

Connector

17

2. Features

a) Maximum Water Supply Period – 6 minutes

Inlet water valve opening, in the harvest cycle, is limited by the harvest timer. The water

valve cannot remain open longer than the maximum period. The water valve can close in

less than six minutes if the harvest cycle is completed.

b) Harvest Backup Timer and Freeze Timer

The harvest backup timer shuts down the icemaker if, for two cycles in a row, the harvest

cycle takes more than 20 minutes to complete. The control board will signal this problem

using 2 beeps every 3 seconds.

The freeze timer shuts down the icemaker if, for two cycles in a row, the freeze cycle

takes longer than the time specified to complete. The control board will signal this

problem using 3 beeps every 3 seconds. The time is factory set using dip switches 9 &

10.

The reset button on the control board must be pressed with power on to reset either of

these safeties.

c) High Temperature Safety

The temperature of the suction line in the refrigeration circuit is limited by the high

temperature safety. This protects the unit from excessively high temperatures. If the

evaporator temperature rises above 127 ± 7°F (53 ± 4°C), the thermistor operates the

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

The control board will signal this problem using 1 beep every 3 seconds. The 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 control 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 harvest cycle.

If the float switch is in the up position (electrical circuit closed), the control board changes

to the ice making cycle. If the float switch is in the down position (electrical circuit open),

the control board changes to additional one minute water fill cycles until water enters the

sump and the float switch closes. When the float switch closes, the control board changes

to the ice making cycle. The unit will not start without adequate water in the sump. This

serves as a low water safety to protect the pump motor 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 and Low Voltage Cut-outs

The maximum and minimum allowable supply voltages of this icemaker are limited by the

high voltage and low voltage cut-outs.

If miswiring (especially on single phase 3 wire models) causes excessive voltage (147Vac

±5% or more) on the control board, the high voltage cut-out shuts down the circuit

in 3 seconds and the icemaker automatically stops. The control board will signal this

problem using 7 beeps every 3 seconds.

The icemaker also automatically stops in cases of insufficient voltage (92Vac ±5% or

less). The control board will signal this problem using 6 beeps every 3 seconds.

When the proper supply voltage is resumed, the icemaker automatically starts running

again.

18

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 OFF.

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 board is 1, 4, 3,

2. For more information, see "II.B. Sequence of Operation."

Sequence Step LED Energized

Components

Time LEDs are On

Min. Max. Avg.

1 Minute Fill Cycle 4 WV 60 seconds

Harvest Cycle 1, 4, and 2 WV, HGV,

Comp, FMR

2 minutes 20 minutes 3 to 5 minutes

Freeze Cycle 1 Comp, PM,

FMR/FMS,

LLV

5 minutes freeze timer

setting

30 to 35 minutes

Reverse Pump Out 1, 3, and 2 Comp, HGV,

PM, FMR

10 seconds 20 seconds factory setting

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

No. of Beeps

(every 3 sec.) Type of Alarm Notes

1 High Evaporator Temp.

(temperature > 127°F)

(53°C)

Check for harvest problem (stuck HGV or

relay), hot water entering unit, stuck HM,

or shorted thermistor.

2 Harvest Backup Timer

(harvest > 20 min. for two

cycles in a row)

Orange LED marked H TIMER lights up.

Check for open thermistor, HGV not

opening, TXV leaking by, low charge, or

inefficient compressor.

3 Freeze Timer

(freeze > specified setting

for two cycles in a row)

Timer is factory set using

dip switches 9 & 10

Yellow LED marked F TIMER lights up.

Check for F/S stuck closed (up), WV

leaking by, HGV leaking by, TXV not

feeding properly, low charge, HM not

bypassing, or inefficient compressor.

To manually reset the above safeties, press the alarm reset button with the power

supply on.

6 Low Voltage

(92Vac ±5% or less)

Red LED will turn off if voltage protection

operates.

The control voltage safeties automatically

reset when voltage is corrected.

7 High Voltage

(147Vac ±5% or more)

Legend: Comp–compressor; FMR–remote fan motor; FMS–self-contained fan motor;

F/S–float switch; HGV–hot gas valve; HM–headmaster (C.P.R.); LLV–Liquid

Line Valve; PM–pump motor; TXV–thermostatic expansion valve; WV–inlet

water valve

19

3. Controls and Adjustments

a) Default Dip Switch Settings

The dip switch is factory-adjusted to the following positions:

Dip Switch No. 1 2 3 4 5 6 7 8 9 10

KM-501MAH OFF ON OFF OFF ON ON OFF OFF ON OFF

KM-501MWH OFF OFF OFF OFF ON ON OFF OFF OFF OFF

KM-501MRH OFF OFF OFF OFF ON ON OFF OFF OFF OFF

Freeze Timer (9 & 10)

Pump-Out Frequency Control (5 & 6)

Pump-Out Timer (3 & 4)

Harvest Timer (1 & 2)

Normally in the OFF position.

b) Harvest Control – Thermistor

A thermistor (semiconductor) is used for a harvest control sensor. The resistance varies

depending on the suction line temperatures. The thermistor detects the temperature of

the evaporator outlet to start the harvest timer. No adjustment is required. If necessary,

check for resistance between thermistor leads, and visually check the thermistor

mounting, located on the suction line next to the evaporator outlet.

Temperature (°F) Temperature (°C) Resistance (kΩ)

0 -18 14.401

10 -12 10.613

32 0 6.000

50 10 3.871

70 21 2.474

90 32 1.633

Check a thermistor for resistance by using the following procedure:

1) Disconnect the connector K3 on the board.

2) Remove the thermistor. See "V.K. Removal and Replacement of Thermistor."

3) Immerse the thermistor sensor portion in a glass containing ice and water for 2 or 3

minutes.

4) Check for a resistance between thermistor leads. Normal reading is within 3.5 to 7 kΩ.

Replace the thermistor if it exceeds the normal reading.

20

c) Harvest Timer (dip switch 1 & 2)

The harvest timer starts counting when the thermistor reads 48°F (9°C) at the

evaporator outlet.

No adjustment is required under normal use, as the harvest timer is adjusted to the

suitable position. However, a setting longer than the factory setting may be advised in

cases where the flush provided at harvest needs to be prolonged for extra cleaning.

Before changing this setting, call the HOSHIZAKI Technical Support Department at

1-800-233-1940 for recommendations. Keep in mind that setting the harvest timer to a

longer setting will decrease 24 hour production.

Dip Switch Setting Time

(seconds)

No. 1 No. 2

OFF OFF 60

ON OFF 90

OFF ON 120

ON ON 180

d) Pump-Out Timer (dip switch 3 & 4)

When a freeze cycle is completed, the pump motor stops, and the icemaker resumes

operation in 2 seconds. Then, during cycles when a pump out is called for, the pump

motor drains the water tank for the time determined by the pump-out timer. The pump-

out timer also acts in place of the harvest timer during cycles with a pump out.

The pump-out timer is factory-adjusted, and no adjustment is required.

Dip Switch Setting Time (seconds)

No. 3 No. 4 T1 T2

OFF OFF 10 150

ON OFF 10 180

OFF ON 10 120

ON ON 20 180

T1: Time to drain the water tank

T2: Harvest timer at pump out

Pump out always occurs on the 2nd harvest after startup. Then, depending on the pump-

out frequency control setting (dip switch 5 & 6), pump out occurs every cycle, or every

2nd, 5th or 10th cycle.

21

e) Pump-Out Frequency Control (dip switch 5 & 6)

The pump motor drains the water tank at the frequency set by the pump-out frequency

control.

The pump-out frequency control is factory-adjusted to drain the water tank every 10

cycles, and no adjustment is required. However, where water quality is bad and the

icemaker needs a pump drain more often, the pump-out frequency can be adjusted as

shown in the table below.

Dip Switch Setting Frequency

No. 5 No. 6

OFF OFF every cycle

ON OFF every 2 cycles

OFF ON every 5 cycles

ON ON every 10 cycles

f) Freeze Timer (dip switch 9 & 10)

CAUTION

Adjust to proper specification, or the unit may not operate correctly.

The freeze timer setting determines the maximum allowed freeze time to prevent

possible freeze-up issues. Upon termination of freeze timer, machine initiates the harvest

cycle. After 2 consecutive timer terminations, machine will shut down, possibly indicating

a problem.

The freeze timer is factory adjusted and no adjustment is required.

Dip Switch Setting Time

(minutes)

No. 9 No. 10

OFF OFF 60

OFF ON 50

ON OFF 70

ON ON 60

g) Bin Control

CAUTION

When the ambient temperature is below 45°F (7°C), the bin control thermostat

operates to stop the icemaker even if the ice storage bin is empty. When the

thermostat is set in the prohibited range, the icemaker operates continuously

even if the ice storage bin is filled with ice. Setting in the prohibited range might

cause severe damage to the icemaker resulting in failure.

No adjustment is required under normal use, as the bin control is factory-adjusted. Adjust

it, if necessary, so that the icemaker stops automatically within 10 seconds after ice

contacts the bin control thermostat bulb.

22

4. Control Board Check Procedure

Before replacing a control board that does not show a visible defect and that you suspect

is bad, always conduct the following check procedure. This procedure will help you verify

your diagnosis.

1) Check the dip switch settings to assure that #3, 4, 7, 8, 9, & 10 are in the factory default

position. On units with a slide-type output test switch, the output test switch (S3) should

be OFF. Switches 1, 2, 5, & 6 are cleaning adjustments and the settings are flexible.

2) Turn the control switch to ICE and check for proper control voltage. If the red LED is ON,

the control voltage is good. If the red LED is OFF, check the control transformer circuit.

3) Check the 115 volt input at the 10-pin connector. Check the brown wire at pin #10 to a

white neutral wire for 115 volts. (Always choose a white neutral wire to establish a good

neutral connection when checking voltages.) A jumper also feeds 115 volts into pin #7.

If no voltage is present, check the 115 volt supply circuit.

4) The output test switch provides a relay sequence test. On units with a slide-type output

test switch, move the control switch to the OFF position, move the output test switch to

the ON position, then move the control switch to the ICE position. On units with a push-

type output test switch, make sure the control switch is in the ICE position, then press

the output test switch. The correct lighting sequence should be none, 2, 3, 4, 1, and 4,

normal sequence every 5 seconds. Components (e.g., the compressor) will cycle during

the test. Note that the order of the relays from the outer edge of the board is 1, 4, 3, 2.

Note: If the LEDs light in a different sequence or the 5–second interval does not occur,

the control board is bad and should be replaced.

5) After checking the sequence, place the output test switch back in the OFF position

on units with a slide-type switch. The output test switch must remain in the OFF

position during normal operation. On units with a push-type output test switch, the unit

automatically resumes normal operation after the test. The unit begins normal operation

with the 1 minute fill cycle.

5. Control Board Replacement

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 to the factory default settings as outlined in this

manual. Dip switch #8 must remain in the OFF position.

23

III. Technical Information

A. Water Circuit and Refrigeration Circuit

1. KM-501MAH (air-cooled)

24

2. KM-501MWH (water-cooled)

25

3. KM-501MRH (remote air-cooled)

26

B. Wiring Diagrams

1. KM-501MAH (air-cooled) and KM-501MWH (water-cooled)

* Pressure Switch

Air-Cooled Model Water-Cooled Model

Cut-out 412±21 PSIG 384±21 PSIG

Cut-in 327±21 PSIG 284±21 PSIG

00

*

27

2. KM-501MRH (remote air-cooled)

*

* Pressure Switch

Cut-out 412±21 PSIG

Cut-in 327±21 PSIG

0

28

C. Timing Chart

*1 The icemaker does not complete a harvest cycle in the first 2 or 3 minutes. See "II.C.3.

Controls and Adjustments."

29

*1 The pump motor waits for 2 seconds before starting a pump-out drain cycle. See "II.C.3.

Controls and Adjustments."

*2 The icemaker does not complete a harvest cycle in the first 2 or 3 minutes. See "II.C.3.

Controls and Adjustments."

30

70/21 498 226 474 215 433 197

80/27 480 218 442 201 397 180

90/32 474 215 416 189 372 169

lbs./day kg./da

y

100/38 463 210 406 184 332 150

70/21

80/27

90/32

watts 100/38

70/21 245 0.93 199 0.75 177 0.67

80/27 210 0.79 139 0.53 139 0.53

90/32 199 0.75 89 0.34 79 0.30

gal./day m3/day 100/38 147 0.56 86 0.33 71 0.27

70/21

80/27

90/32

min. 100/38

70/21

80/27

90/32

min. 100/38

70/21 235 16.5 254 17.9 276 19.4

80/27 250 17.5 279 19.6 298 21.0

90/32 254 17.9 300 21.1 321 22.6

PSIG kg/cm2G100/38 257 18.1 305 21.4 340 23.9

70/21 45 3.2 47 3.3 49 3.5

80/27 47 3.3 50 3.5 52 3.6

90/32 47 3.3 53 3.7 55 3.8

PSIG kg/cm2G100/38 47 3.3 53 3.8 56 3.9

2.3

TOTAL HEAT OF REJECTION FROM CONDENSER 9,200 BTU/h [AT 90ºF (32ºC) / WT 70ºF (21ºC)]

SUCTION PRESSURE

HEAD PRESSURE

3.6

3.2

3.9 2.3

28

29

32

HARVEST CYCLE TIME

1225

1246

1280

33

31

34

36

39

90/32

1169

1161

1188

1210

1219

1140

1156

1161

1194

4.0

26

APPROXIMATE ICE

PRODUCTION PER 24 HR.

APPROXIMATE ELECTRIC

CONSUMPTION

APPROXIMATE WATER

CONSUMPTION PER 24 HR.

FREEZING CYCLE TIME

WATER TEMP. (ºF/ºC)

AMBIENT TEMP.

(ºF/ºC) 50/10 70/21

27

28

30

2.3

4.5

3.2

3.9

3.0

2.3

Note:

1. Pressure data is recorded at 5 minutes into freezing cycle. The data not in bold

should be used for reference only.

2. We reserve the right to make changes in specifications and design without prior

notice.

D. Performance Data

1. KM-501MAH (air-cooled)

31

2. KM-501MWH (water-cooled)

Note:

1. Pressure data is recorded at 5 minutes into freezing cycle. The data not in bold

should be used for reference only.

2. We reserve the right to make changes in specifications and design without prior

notice.

70/21 498 226 495 224 465 211

80/27 496 225 491 223 447 203

90/32 495 224 488 221 449 204

lbs./day kg./da

y

100/38 480 218 479 217 413 187

70/21

80/27

90/32

watts 100/38

70/21 567 2.15 627 2.37 863 3.27

80/27 613 2.32 706 2.67 1027 3.89

90/32 627 2.37 771 2.92 1061 4.02

gal./day m3/day 100/38 783 2.96 839 3.18 1328 5.03

70/21

80/27

90/32

min. 100/38

70/21

80/27

90/32

min. 100/38

70/21 275 19.3 275 19.3 289 20.3

80/27 275 19.3 275 19.3 296 20.8

90/32 275 19.3 275 19.3 293 20.6

PSIG kg/cm2G100/38 282 19.8 279 19.6 310 21.8

70/21 45 3.2 45 3.2 49 3.4

80/27 45 3.2 45 3.2 51 3.6

90/32 45 3.2 45 3.2 50 3.5

PSIG kg/cm2G100/38 47 3.3 46 3.2 55 3.9

TOTAL HEAT OF REJECTION FROM COMPRESSOR 1,400 BTU/h [AT 90ºF (32ºC) / WT 70ºF (21ºC)]

WATER FLOW FOR CONDENSER 52 gal./h [AT 100ºF (38ºC) / WT 90ºF (32ºC)]

PRESSURE DROP OF COOLING WATER LINE less than 10 PSIG

26

26

27

2.0

4.0

2.8

3.4

2.6

2.0

3.6

26

APPROXIMATE ICE

PRODUCTION PER 24 HR.

APPROXIMATE ELECTRIC

CONSUMPTION

APPROXIMATE WATER

CONSUMPTION PER 24 HR.

FREEZING CYCLE TIME

WATER TEMP. (ºF/ºC)

115-120/60/1 50/10 70/21 90/32

1080

1073

1077

1080

1085

1070

1072

1073

28

29

29

31

1089

1100

1101

1120

27

26

27

27

HARVEST CYCLE TIME

HEAD PRESSURE

3.2

2.8

3.4 2.0

2.0

TOTAL HEAT OF REJECTION FROM CONDENSER 6,800 BTU/h [AT 90ºF (32ºC) / WT 70ºF (21ºC)]

SUCTION PRESSURE

32

3. KM-501MRH (remote air-cooled)

Note:

1. Pressure data is recorded at 5 minutes into freezing cycle. The data not in bold

should be used for reference only.

2. We reserve the right to make changes in specifications and design without prior

notice.

70/21 482 219 475 215 437 198

80/27 476 216 465 211 412 187

90/32 475 215 457 207 410 186

lbs./day kg./day 100/38 458 208 446 202 367 166

70/21

80/27

90/32

watts 100/38

70/21 182 0.69 155 0.59 139 0.52

80/27 162 0.61 119 0.45 114 0.43

90/32 155 0.59 90 0.34 79 0.30

gal./day m

3

/day 100/38 123 0.47 87 0.33 70 0.26

70/21

80/27

90/32

min. 100/38

70/21

80/27

90/32

min. 100/38

70/21 220 15.5 235 16.5 259 18.2

80/27 231 16.3 254 17.9 280 19.7

90/32 235 16.5 270 19.0 296 20.8

PSIG kg/cm

2

G100/38 241 16.9 276 19.4 320 22.5

70/21 50 3.5 51 3.6 52 3.7

80/27 50 3.5 51 3.6 53 3.7

90/32 51 3.6 52 3.7 54 3.8

PSIG kg/cm2G100/38 51 3.6 52 3.7 55 3.9

2.1

2.0

3.9

3.0

2.3

26

27

27

29

30

32

WATER TEMP. (ºF/ºC)

AMBIENT TEMP.

(ºF/ºC) 50/10 70/21 90/32

1220

1229

1232

APPROXIMATE ICE

PRODUCTION PER 24 HR.

APPROXIMATE ELECTRIC

CONSUMPTION

APPROXIMATE WATER

CONSUMPTION PER 24 HR.

FREEZING CYCLE TIME

1235

1232

1247

1260

1264

1247

1262

1276

1290

SUCTION PRESSURE

TOTAL HEAT OF REJECTION FROM CONDENSER

31

27

28

30

HARVEST CYCLE TIME

HEAD PRESSURE

2.3

4.5

8000 BTU/h [AT 90ºF (32ºC) / WT 70ºF (21ºC)]

1500 BTU/h [AT 90ºF (32ºC) / WT 70ºF (21ºC)]

74.5 CU. IN (URC-6F)

33

36

4.0

3.9

3.0

3.5

3.0

TOTAL HEAT OF REJECTION FROM COMPRESSOR

CONDENSER VOLUME

33

IV. Service Diagnosis

A. 10-Minute KM Diagnostic Procedure

The 10 minute check out procedure is basically a sequence check which can be used

at unit start-up or for system diagnosis. Using this check out procedure will allow you

to diagnose electrical system and component failures in approximately 10 minutes

under normal operating conditions of 70°F or warmer air and 50°F or warmer water

temperatures. Before conducting a 10 minute checkout, check for correct installation,

proper voltage per unit nameplate and adequate water supply. As you go through the

procedure, check to assure the components energize and de-energize correctly. If not,

those components and controls are suspect. Check for voltage at the 10-pin connector.

1) Turn power OFF and access the control box.

2) Turn power ON and place the control switch in ICE position. A 5 second delay occurs.

3) One Minute Fill Cycle – The inlet water valve is energized. After 1 minute, the control

board checks the float switch. If the float switch is closed, the unit cycles to harvest. If

closed, continue to step 4. If the float switch is open, the unit repeats the 1 minute fill

cycle until water enters and the float switch closes (low water safety protection during

initial start up and at the end of each harvest). Diagnosis: If the water valve does not

open, check for no supply voltage at water valve terminals, bad coil, or plugged screen

or external filter (no water flow). If unit fails to start harvest, check for open float switch

or bad 1 minute timer in board.

4) Initial Harvest Cycle – Inlet water valve remains energized, contactor coil energizes to

start the compressor (and fan motor on a remote condenser unit), and the hot gas valve

energizes. The evaporator warms and the thermistor senses 48°F (9°C). The control

board then receives the thermistor's 3.9 kΩ signal and turns operation of harvest over

to the harvest timer. The timer completes counting (1 to 3 minutes). The unit then cycles

to freeze. Diagnosis: Check if compressor is running, hot gas valve is open, water

valve still open. Average harvest cycle at factory setting is 2 to 3 minutes. How long

does initial harvest last? 1.5 minutes after initial harvest begins, touch the compressor

discharge line. Is it hot? If not check refrigerant pressures and compressor operation.

If it is hot, touch the inlet line to the evaporator. Is it hot? If it is hot and the freeze cycle

is not starting, check the harvest timer adjustment, the thermistor for open circuit, the

discharge line temperature, compressor efficiency, and if the hot gas valve is fully open.

5) Freeze Cycle – compressor remains energized, pump motor, (line valve on remote

condenser unit), and fan motor energize. The inlet water valve and hot gas valve

de-energize. The unit is held in freeze by a 5 minute short cycle protection timer.

After 5 minutes, the freeze cycle operation is transferred to the float switch for

freeze termination. During the first 5 minutes of freeze, confirm that the evaporator

temperature drops. After 7 minutes in freeze, remove the black float switch lead

from the K5 connector. The unit should immediately switch to the pump-out cycle.

Diagnosis: If the evaporator is not cold, check to see if the hot gas valve is still open

or if the expansion valve is not opening properly, if the water valve is continuing to fill

the reservoir, if there are improper unit pressures, an inoperative compressor, or an

inoperative headmaster (C.P.R.) (remote condenser unit only). If the unit remains in

34

freeze with the float switch removed, replace the board.

Note: Normal freeze cycle will last 20 to 40 minutes depending on model and

conditions. Cycle times and pressures should follow performance data provided

in this manual.

6) Pump-Out Cycle (10/20 second pump out) – the compressor remains energized,

the hot gas valve energizes, the fan motor de-energizes, the pump motor stops for

2 seconds and starts in reverse rotation for 10/20 seconds. (This removes contaminants

from the water reservoir through the check valve (drain valve) and down the drain and

allows for a power flush of the float switch.) Check for clear tubing at the check valve

housing and check the unit drain for water flow. Diagnosis: If the pump motor does not

reverse, check the circuit and capacitor. If water does not pump out, remove the check

valve (drain valve) housing and check/clean the valve assembly.

7) Normal Harvest Cycle – same as the initial harvest cycle – Return to step 4.

Note: Unit continues to cycle until bin control is satisfied or power is switched OFF. (The

pump out cycle can be adjusted to occur every cycle, or every 2, 5, or 10 cycles.

The factory default is every 10 cycles.) The unit always restarts at the 1 minute fill

cycle.

B. Diagnostic Charts

1. No Ice Production

Problem Possible Cause Remedy

[1] The icemaker will not

start.

a)Power Supply 1. OFF position. 1. Move to ON position.

2. Loose connection. 2. Tighten.

3. Bad contacts. 3. Check for continuity and

replace.

4. Voltage too high or too

low.

4. Check and get

recommended voltage.

b)Fuse (Inside fused

disconnect, if any)

1. Blown. 1. Check for short circuit and

replace.

c) Control Switch 1. OFF position. 1. Move to ICE position.

2. Bad contacts. 2. Check for continuity and

replace.

d)Bin Control Thermostat 1. Tripped with bin filled

with ice.

1. Remove ice.

2. Ambient temperature

too cool.

2. Increase ambient

temperature.

3. Set too warm. 3. See "II.C.3. Controls

and Adjustments, g) Bin

Control."

4. Bulb out of position. 4. Place in position.

5. Bad contacts. 5. Check for continuity and

replace.

e)High Pressure Control 1. Bad contacts. 1. Check for continuity and

replace.

2. Dirty air filter or

condenser.

2. Clean.

35

Problem Possible Cause Remedy

3. Ambient or condenser

water temperature too

warm.

3. Reduce temperature.

4. Refrigerant

overcharged.

4. Recharge.

5. Fan not operating.

(except water-cooled

model)

5. See chart 1.[6]

6. Refrigerant line or

components plugged.

6. Clean and replace drier.

7. Condenser water

pressure too low or off.

(water-cooled model

only)

7. Check and get

recommended pressure.

f) Transformer 1. Coil winding opened

or shorted.

1. Replace.

g)Wiring to Control Board 1. Loose connections or

open.

1. Check for continuity and

replace.

h)Thermistor 1. Leads shorted or

opened and high

temperature or harvest

backup timer safety

operates. (1 beep or 2

beep alarm)

1. See "II.C.3. Controls and

Adjustments, b) Harvest

Control."

i) Hot Gas Valve 1. Continues to open

in freeze cycle and

freeze timer safety

operates. (3 beep

alarm)

1. Check for hot gas valve

stuck open and replace.

j) Water Supply Line 1. Water supply off and

water supply cycle

does not finish.

1. Check and get

recommended pressure.

2. Condenser water

pressure too low

or off and pressure

control opens and

closes frequently to

finally operate high

temperature safety.

(1 beep alarm)

2. Check and get

recommended pressure.

k) Inlet Water Valve 1. Mesh filter or orifice

gets clogged and

water supply cycle

does not finish.

1. Clean.

2. Coil winding opened. 2. Replace.

3. Wiring to water valve. 3. Check for loose

connection or open, and

replace.

l) Control Board 1. Defective or in alarm. 1. See "II.C.4. Control Board

Check Procedure."

36

Problem Possible Cause Remedy

m)Interlock Switch Open

(Cleaning Valve)

1. Misaligned. 1. Realign.

2. Bad contacts. 2. Check for continuity and

replace.

n)Wash Switch 1. WASH position. 1. Move to ICE position.

2. Bad contacts. 2. Check and replace.

[2] Water continues to

be supplied, and the

icemaker will not

start.

a)Float Switch 1. Connector

disconnected.

1. Place in position.

2. Leads opened or

defective switch.

2. Check and replace.

3. Float does not move

freely.

3. Clean or replace.

b)Control Board 1. Defective. 1. Replace.

[3] Compressor will

not start or stops

operating.

a)Magnetic Contactor 1. Bad contacts. 1. Check for continuity and

replace.

2. Coil winding opened. 2. Replace.

b)Start Capacitor or Run

Capacitor

1. Defective. 1. Replace.

c) Internal Overload

Protector Open (check

1 through 3 to the right

and d through f below)

1. Loose terminal. 1. Tighten or replace.

2. Voltage. 2. Check and correct.

3. Dirty condenser. 3. Clean.

d)Starter 1. Bad contacts. 1. Check and replace.

2. Coil winding opened. 2. Replace.

e)Compressor 1. Wiring to compressor. 1. Check for loose

connection or open, and

replace.

2. Defective. 2. Replace.

3. Protector tripped. 3. Reduce temperature.

f) Control Board 1. No power to contactor. 1. See "II.C.4. Control Board

Check Procedure."

[4] Water continues to

be supplied in freeze

cycle.

a)Inlet Water Valve 1. Diaphragm does not

close.

1. Check for water leaks with

icemaker off.

b)Control Board 1. Defective. 1. See "II.C.4. Control Board

Check Procedure."

[5] No water comes from

spray tubes. Water

pump will not start, or

freeze cycle time is

too short.

a)Water Supply Line 1. Water pressure too

low and water level in

water tank too low.

1. Check and get

recommended pressure.

b)Inlet Water Valve 1. Dirty mesh filter or

orifice and water level

in water tank too low.

1. Clean.

c) Water System 1. Water leaks. 1. Check connections for

water leaks, and replace.

37

Problem Possible Cause Remedy

2. Clogged. 2. Clean.

3. Pump out check valve

leaking by.

3. Check assembly and

clean.

d)Pump Motor 1. Motor winding opened. 1. Replace.

2. Bearing worn out. 2. Replace.

3. Wiring to pump motor. 3. Check for loose

connection or open, and

replace.

4. Defective capacitor. 4. Replace.

5. Defective or bound

impeller.

5. Replace and clean.

6. Mechanical seal worn

out.

6. Check and replace.

e)Control Board 1. Defective. 1. See "II.C.4. Control Board

Check Procedure."

[6] Fan motor will

not start, or is not

operating.

a)Fan Motor 1. Motor winding opened. 1. Replace.

2. Bearing worn out. 2. Replace.

3. Wiring to fan motor. 3. Check for loose

connection or open, and

replace.

4. Defective capacitor. 4. Replace.

5. Fan blade bound. 5. Check and replace.

b)Control Board 1. Defective. 1. See "II.C.4. Control Board

Check Procedure."

[7] All components

run, but no ice is

produced.

a)Refrigerant 1. Undercharged. 1. Check for leaks and

recharge.

2. Air or moisture

trapped.

2. Replace drier and

recharge.

b)Compressor 1. Defective valve. 1. Replace.

c) Hot Gas Valve 1. Continues to open in

freeze cycle.

1. Check and replace.

d)Line Valve 1. Continues to close in

freeze cycle.

1. Check and replace.

e)Inlet Water Valve 1. Water valve is wide

open during freeze.

1. Check for water leaks with

icemaker off.

f) Headmaster (C.P.R.)

(Remote Unit)

1. Not operating properly

and liquid line

temperature too warm.

1. Replace headmaster.

g)Water Supply Line

(water-cooled model

only)

1. Condenser water

pressure too low or off

and pressure control

opens and closes

frequently.

1. Check and get

recommended pressure.

h)Water Regulator

(water-cooled model

only)

1. Set too high. 1. Adjust or replace. See

"V.I. Adjustment of Water

Regulating Valve."

38

2. Evaporator is Frozen Up

Problem Possible Cause Remedy

[1]Freeze cycle time is

too long.

a)Float Switch 1. Leads short-circuit or

defective switch.

1. Check and replace.

2. Float does not move

freely.

2. Clean or replace.

b)Inlet Water Valve 1. Diaphragm does not

close.

1. Check for water leaks with

icemaker off.

c) Control Board 1. Defective. 1. See "II.C.4. Control Board

Check Procedure."

[2]All ice formed on

evaporator does not

fall into bin in harvest

cycle.

a)Evaporator 1. Scaled up. 1. Clean.

b)Water Supply Line 1. Water pressure too

low.

1. Check and get

recommended pressure.

c) Water Filter System 1. Dirty/Restricted 1. Replace filter.

d)Inlet Water Valve 1. Dirty mesh filter or

orifice.

1. Clean.

2. Diaphragm does not

close.

2. Check for water leaks with

icemaker off.

e) Ambient and/or water

temperature.

1. Too cool. 1. Increase temperature.

f) Line Valve 1. Continues to open in

harvest cycle.

1. Check operation in harvest

cycle and replace.

g)Thermistor 1. Out of position or

loose attachment.

1. See "V.I. Removal

and Replacement of

Thermistor."

h)Control Board 1. Harvest timer is set

too short.

1. Adjust longer, referring

to "II.C.3. Controls and

Adjustments, c) Harvest

Timer.

2. Defective. 2. See "II.C.4. Control Board

Check Procedure."

[3]Other a)Spray Tubes 1. Clogged. 1. Clean

2. Out of position. 2. Place in position.

b)Water System 1. Dirty. 1. Clean.

c) Refrigerant 1. Undercharged. 1. Check for leaks and

recharge.

d)Expansion Valve 1. Bulb out of position or

loose attachment.

1. Place in position.

2. Defective. 2. Replace.

e)Hot Gas Valve 1. Coil winding opened. 1. Replace.

2. Plunger does not

move.

2. Replace.

3. Wiring to hot gas

valve.

3. Check for loose

connection or open, and

replace.

f) Ice Cube Guide 1. Out of position and ice

trapped.

1. Place in position.

39

Problem Possible Cause Remedy

g)Water Supply Line 1. Too small; requires

3/8" OD line dedicated

per machine.

1. Increase water line size.

h)Water Filter 1. Flow rate too small. 1. Replace with filter that has

larger flow rate.

3. Low Ice Production

Problem Possible Cause Remedy

[1] Freeze cycle time is

long.

a) See chart 1.[3] and check dirty air filter or condenser, ambient or water

temperature, water pressure, condenser water regulating valve (water-cooled

model), and refrigerant charge.

b) See chart 2.[1] and check float switch, inlet water valve and control board.

c) Check pump, hot gas valve, headmaster (C.P.R.) (remote air-cooled model),

expansion valve, refrigeration check valve, and compressor.

[2] Harvest cycle time is

long.

a) See chart 2.[2] and check control board, thermistor, evaporator, ambient and/or

water temperature, water supply line, inlet water valve, line valve, and gas valve.

4. Abnormal Ice

Problem Possible Cause Remedy

[1] Small cubes. a) Ice Cube Guide 1. Out of position.

Circulated water falls

into bin.

1. Place in position.

b) See chart 1.[5] and check water supply line, inlet water valve, water system,

pump motor, and control board.

c) Pump Out Check Valve 1. Dirty. 1. Clean.

[2] Cloudy or irregular

cubes.

a) See chart 2.[1] and 2.[3], and check float switch, inlet water valve, control

board, spray tubes, water system, refrigerant charge, and expansion valve.

b) Spray Guide 1. Dirty. 1. Clean.

c) Water Quality 1. High hardness or

contains impurities.

1. Install a water softener or

filter.

5. Other

Problem Possible Cause Remedy

[1] Icemaker will not stop

when bin is filled with

ice.

a) Bin Control Thermostat 1. Set too cold. 1. Adjust warmer.

2. Defective. 2. Replace

[2] Abnormal noise. a) Pump Motor 1. Bearings worn out. 1. Replace

b) Fan Motor 1. Bearings worn out. 1. Replace

2. Fan blade deformed. 2. Replace fan blade.

3. Fan blade does not

move freely.

3. Replace.

c) Compressor 1. Bearings worn out or

cylinder valve broken.

1. Replace.

40

Problem Possible Cause Remedy

2. Mounting pad out of

position.

2. Reinstall.

d) Refrigerant Lines 1. Rub or touch other

lines or surfaces.

1. Replace.

[3] Ice in storage bin

often melts.

a) Drain Line(s) 1. Plugged. 1. Clean.

b) Icemaker and Bin 1. Drains not run

separately.

1. Separate the drain lines.

c) Ice Cube Guide 1. Out of position.

Circulated water falls

into bin.

1. Place in position.

41

V. Removal and Replacement of Components

IMPORTANT

Ensure all components, fasteners and thumbscrews are securely in place after

the equipment is serviced.

IMPORTANT

1. The Polyol Ester (POE) oils used in R-404A units can absorb moisture

quickly. Therefore it is important to prevent moisture from entering the system

when replacing or servicing parts.

2. Always install a new filter drier every time the sealed refrigeration system is

opened.

3. Do not leave the system open for longer than 15 minutes when replacing or

servicing parts.

A. Service for Refrigerant Lines

1. Refrigerant Recovery

The icemaker unit is provided with two refrigerant access valves–one on the low-side and

one on the high-side line. Using proper refrigerant practices recover the refrigerant from the

access valves and store it in an approved container. Do not discharge the refrigerant into

the atmosphere.

2. Evacuation and Recharge (R-404A)

1) Attach charging hoses, a service manifold and a vacuum pump to the system. Be sure

to connect charging hoses to both high and low-side access valves.

IMPORTANT

The vacuum level and vacuum pump may be the same as those for current

refrigerants. However, the rubber hose and gauge manifold to be used for

evacuation and refrigerant charge should be exclusively for POE oils.

2) Turn on the vacuum pump. Never allow the oil in the vacuum pump to flow backward.

3) Allow the vacuum pump to pull down to a 29.9" Hg vacuum. Evacuating period depends

on pump capacity.

4) Close the low-side valve and high-side valve on the service manifold.

5) Disconnect the vacuum pump, and attach a refrigerant service cylinder to the high-

side line. Remember to loosen the connection, and purge the air from the hose. See

the nameplate for the required refrigerant charge. Hoshizaki recommends only virgin

refrigerant or reclaimed refrigerant which meets ARI Standard No. 700-88 be used.

6) A liquid charge is recommended for charging an R-404A system. Invert the service

cylinder. Open the high-side, service manifold valve.

7) Allow the system to charge with liquid until the pressures balance.

42

8) If necessary, add any remaining charge to the system through the low-side. Use a

throttling valve or liquid dispensing device to add the remaining liquid charge through

the low-side access port with the unit running.

9) Close the two refrigerant access valves, and disconnect the hoses and service

manifold.

10) Cap the access valves to prevent a possible leak.

B. Brazing

DANGER

1. Refrigerant R-404A itself is not flammable at atmospheric pressure and

temperatures up to 176°F (80°C).

2. Refrigerant R-404A itself is not, explosive or poisonous. However, when

exposed to high temperatures (open flames), R-404A can be decomposed to

form hydrofluoric acid and carbonyl fluoride both of which are hazardous.

3. Always recover the refrigerant and store it in an approved container. Do not

discharge the refrigerant into the atmosphere.

4. Do not use silver alloy or copper alloy containing arsenic.

5. Do not use R-404A as a mixture with pressurized air for leak testing.

Refrigerant leaks can be detected by charging the unit with a little refrigerant,

raising the pressure with nitrogen and using an electronic leak detector.

Note: All brazing-connections inside the evaporator case are clear-paint coated.

Sandpaper the brazing connections before unbrazing the components. Use a

good abrasive cloth to remove the coating.

C. Removal and Replacement of Compressor

IMPORTANT

Always install a new drier every time the sealed refrigeration system is opened.

Do not replace the drier until after all other repair or replacement has been

made.

Note: When replacing a compressor with a defective winding, be sure to install the

new start capacitor and start relay supplied with the replacement compressor.

Due to the ability of the POE oil in the compressor to absorb moisture quickly,

the compressor must not be opened more than 15 minutes for replacement or

service. Do not mix lubricants of different compressors even if both are charged

with R-404A, except when they use the same lubricant.

1) Turn off the power supply.

2) Remove the panels.

3) Recover the refrigerant and store it in an approved container.

43

4) Remove the terminal cover on the compressor, and disconnect the compressor wiring.

5) Remove the discharge and suction pipes using brazing equipment.

6) Remove the hold-down bolts, washers and rubber grommets.

7) Slide and remove the compressor. Unpack the new compressor package. Install the

new compressor.

8) Attach the rubber grommets of the prior compressor.

9) Sandpaper the suction, discharge and process pipes.

10) Place the compressor in position, and secure it using the bolts and washers.

11) Remove plugs from the suction, discharge and process pipes.

12) Braze the process, suction and discharge lines (do not change this order), while purging

with nitrogen gas flowing at a pressure of 3 to 4 PSIG.

13) Install the new drier.

14) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.

15) Evacuate the system, and charge it with refrigerant. For air-cooled and water-cooled

models, see the nameplate for the required refrigerant charge. For remote air-cooled

models, see the charge label in the machine compartment.

16) Connect the terminals, and replace the terminal cover in its correct position.

17) Replace the panels in their correct positions.

18) Turn on the power supply.

D. Removal and Replacement of Drier

IMPORTANT

Always install a new drier every time the sealed refrigeration system is opened.

Do not replace the drier until after all other repair or replacement has been

made.

1) Turn off the power supply.

2) Remove the panels.

3) Recover the refrigerant and store it in an approved container.

4) Remove the drier.

5) Install the new drier with the arrow on the drier in the direction of the refrigerant flow.

Use nitrogen gas at a pressure of 3 to 4 PSIG when brazing the tubings.

6) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.

7) Evacuate the system, and charge it with refrigerant. For air-cooled and water-cooled

models, see the nameplate for the required refrigerant charge. For remote air-cooled

models, see the charge label in the machine compartment.

8) Replace the panels in their correct positions.

9) Turn on the power supply.

44

E. Removal and Replacement of Expansion Valve

IMPORTANT

Sometimes moisture in the refrigeration circuit exceeds the drier capacity and

freezes up at the expansion valve. Always install a new drier every time the

sealed refrigeration system is opened. Do not replace the drier until after all

other repair or replacement has been made.

1) Turn off the power.

2) Remove the panels.

3) Recover the refrigerant and store it in an approved container.

4) Remove the insulation and the expansion valve bulb on the suction line.

5) Remove the expansion valve cover, and disconnect the expansion valve using brazing

equipment.

6) Braze the new expansion valve with nitrogen gas flowing at the pressure of 3 to 4 PSIG.

WARNING

Always protect the valve body by using a damp cloth to prevent the valve from

overheating. Do not braze with the valve body exceeding 250°F (121°C).

7) Install the new drier.

8) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.

9) Evacuate the system, and charge it with refrigerant. For air-cooled and water-cooled

models, see the nameplate for the required refrigerant charge. For remote air-cooled

models, see the charge label in the machine compartment.

10) Attach the expansion valve bulb to the suction line in the same location as the previous

bulb. The bulb should be at the 12 o'clock position on the tube. Be sure to secure the

bulb with the clamp and holder and to insulate it.

11) Place the expansion valve cover in position.

12) Replace the panels in their correct positions.

13) Turn on the power supply.

F. Removal and Replacement of Hot Gas Valve and Line Valve

IMPORTANT

1. Always use a copper tube of the same diameter and length when replacing

the hot gas lines; otherwise the performance may be reduced.

2. Always install a new drier every time the sealed refrigeration system is

opened. Do not replace the drier until after all other repair or replacement

has been made.

3. Always replace the strainer when replacing the hot gas valve.

45

1) Turn off the power supply.

2) Remove the panels.

3) Recover the refrigerant and store it in an approved container.

4) Remove the screw and the solenoid.

5) Disconnect the hot gas valve or line valve using brazing equipment.

6) Install the new valve.

CAUTION

Always protect the valve body by using a damp cloth to prevent the valve from

overheating. Do not braze with the valve body exceeding 250°F (121°C).

7) Install the new drier.

8) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.

9) Evacuate the system, and charge it with refrigerant. For air-cooled and water-cooled

models, see the nameplate for the required refrigerant charge. For remote air-cooled

models, see the charge label in the machine compartment.

10) Cut the leads of the solenoid allowing enough lead length to reconnect using closed

end connectors.

11) Connect the new solenoid leads.

12) Attach the solenoid to the valve body, and secure it with a screw.

13) Replace the panels in their correct positions.

14) Turn on the power supply.

G. Removal and Replacement of Evaporator

IMPORTANT

Always install a new drier every time the sealed refrigeration system is opened.

Do not replace the drier until after all other repairs or replacement have been

made.

1) Turn off the power supply.

2) Remove the panels and the top insulation over the evaporator.

3) Recover the refrigerant and store it in an approved container.

4) Remove the spray tubes and the insulations at the "U" shaped notch where the

refrigeration tubings go through the molded chassis.

5) Remove the insulation tube, and disconnect the evaporator inlet tubing at the tee next

to the expansion valve.

6) Lift up the evaporator, and disconnect the evaporator outlet tubing.

7) Install the new evaporator.

8) Install the new drier.

9) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.

46

10) Evacuate the system, and charge it with refrigerant. For air-cooled and water-cooled

models, see the nameplate for the required refrigerant charge. For remote air-cooled

models, see the charge label in the machine compartment.

11) Replace the removed parts in the reverse order of which they were removed.

12) Replace the top insulation and the panels in their correct positions.

13) Turn on the power supply.

H. Removal and Replacement of Water Regulating Valve -

Water Cooled Model Only

IMPORTANT

Always install a new drier every time the sealed refrigeration system is opened.

Do not replace the drier until after all other repair or replacement has been

made.

1) Turn off the power supply.

2) Close the water supply line shut-off valve.

3) Remove the panels.

4) Recover the refrigerant and store it in an approved container.

5) Disconnect the capillary tube at the condenser outlet using brazing equipment.

6) Disconnect the flare-connections of the valve.

7) Remove the screws and the valve from the bracket.

8) Install the new valve, and braze the capillary tube.

9) Install the new drier.

10) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.

11) Evacuate the system, and charge it with refrigerant. See the nameplate for the required

refrigerant charge.

12) Connect the flare-connections.

13) Open the water supply line shut-off valve.

14) Check for water leaks.

15) Replace the panels in their correct positions.

16) Turn on the power supply.

I. Adjustment of Water Regulating Valve - Water-Cooled Model Only

The water regulating valve (also called "water regulator") is factory-adjusted. No adjustment

is required under normal use. Adjust the water regulator, if necessary, using the following

procedures.

1) Prepare a thermometer to check the condenser drain temperature. Attach a pressure

gauge to the high-side line of the system.

47

2) Five minutes after a freeze cycle starts, confirm that the thermometer reads 104°F to

115°F (40°C to 46°C). If it does not, rotate the adjustment screw by using a flat blade

screwdriver until the temperature is in the proper range. See Fig. 1. Next, check that

the reference pressure is in the range indicated in the Head Pressure table in the

Performance Data section. If it is not in the proper range, verify the refrigerant charge.

3) Check that the condenser drain temperature is stable.

J. Removal and Replacement of Headmaster (Condensing Pressure

Regulator - C.P.R.) - Remote Air-Cooled Model Only

IMPORTANT

Always install a new drier every time the sealed refrigeration system is opened.

Do not replace the drier until after all other repair or replacement has been

made.

1) Turn off the power supply.

2) Remove the panels from the remote condenser unit.

3) Recover the refrigerant and store it in an approved container.

4) Before heating, break off the stub on the dome to release the dome charge.

5) Disconnect the headmaster using brazing equipment.

6) Install the new headmaster. Use nitrogen gas at a pressure of 3 to 4 PSIG when brazing

the headmaster.

CAUTION

Always protect the headmaster body by using a damp cloth to prevent it from

overheating. Do not braze with the headmaster body exceeding 250°F (121°C).

7) Install the new drier in the icemaker.

8) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.

9) Evacuate the system and charge it with refrigerant. See the charge label in the machine

compartment in the icemaker.

Fig. 1

Adjustment

Screw

CW – Higher

CCW – Lower

Top View

48

10) Replace the panels in their correct positions.

11) Turn on the power supply.

K. Removal and Replacement of Thermistor

IMPORTANT

1. Fragile, handle very carefully.

2. Always use a recommended sealant (High Thermal Conductive Type), Model

KE4560RTV manufactured by SHINETSU SILICONE, Part Code 60Y000-11,

or Part Code 4A0683-01 equivalent.

3. Always use a recommended foam insulation (non-absorbent type) or

equivalent.

4. Do not shorten or cut the thermistor leads when installing it.

1) Turn off the power supply.

2) Remove the panels.

3) Remove the control box cover.

4) Disconnect the thermistor leads from the

K3 connector on the control board.

5) Remove the plastic cable ties, foam

insulation, thermistor holder and thermistor.

See Fig. 2.

6) Scrape away the old sealant on the

thermistor holder and the suction pipe.

7) Wipe off moisture or condensation on the

suction pipe.

8) Smoothly apply recommended sealant (KE4560RTV, Part Code 60Y000-11 or

4A0683-01) to the thermistor holder concave.

9) Attach the new thermistor to the suction pipe very carefully to prevent damage to the

leads. Secure it using the thermistor holder and recommended foam insulation.

10) Secure the insulation using the plastic cable ties.

11) Connect the thermistor leads through the bushing of the control box to the K3 connector

on the control board.

Note: Do not cut the leads of the thermistor while installing it.

12) Replace the control box cover and the panels in their correct positions.

13) Turn on the power supply.

Foam Insulation Thermistor Holder

Thermistor Lead Cable Tie

Fig. 2

49

L. Removal and Replacement of Fan Motor

Note: When replacing a fan motor with defective winding, it is recommended that a new

capacitor be installed.

1) Turn off the power supply.

2) Remove the panels.

3) Remove the junction box cover from the remote condenser unit (remote air-cooled

model).

4) Remove the closed end connectors from the fan motor leads.

5) Remove the fan motor bracket and fan motor.

6) Install the new fan motor, and replace the removed parts in the reverse order of which

they were removed.

7) Replace the panels in their correct positions.

8) Replace the junction box cover in its correct position (remote air-cooled model).

9) Turn on the power supply.

M. Removal and Replacement of Inlet Water Valve

1) Turn off the power supply.

2) Close the water supply line shut-off valve.

3) Remove the front panel.

4) Remove the valve outlet tubing by releasing the clamp.

5) Remove the bracket from the unit.

6) Remove the fitting nut and water valve.

7) Disconnect the terminals from the water valve.

8) Install the new water valve, and replace the removed parts in the reverse order of which

they were removed.

9) Open the water supply line shut-off valve.

10) Turn on the power supply.

11) Check for leaks.

12) Replace the front panel in its correct position.

N. Removal and Replacement of Pump Motor

1) Turn off the power supply.

2) Remove the front panel.

3) Remove the base cover.

4) Drain the water tank by removing one end of the pump tubing.

5) Replace the removed parts in their correct positions.

6) Disconnect the pump suction and discharge hoses. Fig. 3

50

7) Remove the closed end connectors from the pump motor leads.

8) Remove the screw attaching the pump motor assembly to the base, then remove the

pump motor assembly.

9) Remove the screw attaching the pump motor to the pump motor bracket.

10) Remove the screws attaching the pump housing to the pump motor. Remove the

housing and check the impeller.

11) If the impeller is defective, install a new impeller.

12) Install the new motor or new parts, and replace the removed parts in the reverse order

of which they were removed.

13) Turn on the power supply and check for leaks.

14) Replace the base cover in its correct position.

15) Replace the front panel in its correct position.

O. Removal and Replacement of Spray Tubes

1) Turn off the power supply.

2) Remove the front panel and the insulation panel.

3) Remove the rubber hoses from the spray tubes (water supply pipe).

4) Release the clamps, and disconnect the rubber hoses.

5) Remove the spray tubes by squeezing the side tabs.

6) Install the new spray tubes, and replace the removed parts in the reverse order of which

they were removed.

7) Replace the panels in their correct positions.

8) Turn on the power supply.

51

VI. Cleaning and Maintenance Instructions

IMPORTANT

Ensure all components, fasteners and thumbscrews are securely in place after

any maintenance or cleaning is done to the equipment.

A. Cleaning and Sanitizing Procedures

WARNING

1. HOSHIZAKI recommends cleaning this unit at least once a year. More

frequent cleaning, however, may be required in some existing water

conditions.

2. To prevent injury to individuals and damage to the icemaker, do not use

ammonia type cleaners.

3. Always wear liquid-proof gloves to prevent the cleaning and sanitizing

solutions from coming into contact with skin.

IMPORTANT

1. The cleaning valve is used to allow solution flow to the inside of the

evaporator during the cleaning and sanitizing operations. It should be closed

for all icemaking operation. The compressor will not operate unless this valve

is completely closed.

2. To open the cleaning valve, the valve handle should be parallel to the valve

body. To close the valve, the valve handle should be at a right angle to the

valve body.

52

1. Cleaning Procedure

1) Dilute approximately 16 fl. oz. of the recommended cleaner Hoshizaki "Scale Away" or

"LIME-A-WAY" (Economics Laboratory, Inc.) with 3 gal. of water.

2) Remove all ice from the evaporator and the storage bin.

Note: To remove cubes on the evaporator, turn off the power supply and turn it on

after 3 minutes. The defrost cycle starts and the cubes will be removed from the

evaporator.

3) Turn off the power supply.

4) Remove the front panel and the base

cover, and then remove the insulation

panel by lifting up the panel slightly and

pulling it towards you.

5) Remove one end of the pump tubing (see

Fig. 4). Drain the water tank. Replace the

pump tubing in its correct position.

6) In bad or severe water conditions, clean the float switch assembly as described below.

Otherwise, continue to step 7.

a. Remove the float switch assembly from the mounting bracket and remove the

rubber boot from the bottom of the assembly.

b. Remove the retainer rod from the bottom of the float switch assembly, then remove

the float. Be careful not to bend the retainer rod excessively when removing it.

c. Wipe down the float switch assembly's housing, shaft, float, and retainer rod with

cleaning solution. Wipe the inside of the rubber boot with cleaning solution.

d. Reassemble the float switch assembly and replace it and the rubber boot in their

correct positions.

7) Pour the cleaning solution into the water tank.

8) Fully open the cleaning valve on the left side wall of the machine compartment.

9) Move the control switch on the control box to the "WASH" position.

10) Replace the insulation panel and the front panel in their correct positions.

11) Turn on the power supply, and start the washing process.

12) Turn off the power supply after 30 minutes.

13) Remove the front panel.

14) Remove one end of the pump tubing. Drain the water tank. Replace the pump tubing in

its correct position.

15) Move the control switch to the "ICE" position.

16) Close the cleaning valve.

Note: The icemaker will not operate unless the cleaning valve is completely closed.

17) Replace the front panel in its correct position.

18) Turn on the power supply to fill the water tank with water.

19) Turn off the power supply after 3 minutes.

Fig. 4

53

20) Remove the front panel, and fully open the cleaning valve.

21) Move the control switch to the "WASH" position.

22) Replace the front panel in its correct position.

23) Turn on the power supply to rinse off the cleaning solution.

24) Turn off the power supply after 5 minutes.

25) Remove the front panel.

26) Remove one end of the pump tubing. Drain the water tank. Replace the pump tubing in

its correct position.

27) Repeat steps 15 through 26 three more times to rinse thoroughly.

Note: If you do not sanitize the icemaker, go to step 10 in "2. Sanitizing Procedure."

2. Sanitizing Procedure - Following Cleaning Procedure

1) Dilute a 5.25% sodium hypochlorite solution (chlorine bleach) with water (add 1.5 fl. oz.

of sanitizer to 3 gal. of water).

2) Remove the insulation panel.

3) Pour the sanitizing solution into the water tank.

4) Replace the insulation panel and the front panel in their correct positions.

Note: Make sure that the control switch is in the "WASH" position and the cleaning

valve is open.

5) Turn on the power supply, and start the sanitizing process.

6) Turn off the power supply after 15 minutes.

7) Remove the front panel.

8) Remove one end of the pump tubing. Drain the water tank. Replace the pump tubing in

its correct position.

9) Repeat steps 15 through 26 in "1. Cleaning Procedure" two times to rinse thoroughly.

10) Close the cleaning valve.

11) Move the control switch to the "ICE" position.

12) Replace the front panel and the base cover in their correct positions.

13) Clean the storage bin with water.

14) Turn on the power supply, and start the automatic icemaking process.

B. Maintenance

IMPORTANT

This icemaker must be maintained individually, referring to the instruction

manual and labels provided with the icemaker.

1. Stainless Steel Exterior

To prevent corrosion, wipe the exterior occasionally with a clean and soft cloth. Use a

damp cloth containing a neutral cleaner to wipe off oil or dirt build up.

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2. Storage Bin and Scoop

• Wash your hands before removing ice. Use the plastic scoop provided (Accessory).

• The storage bin is for ice use only. Do not store anything else in the bin.

• Keep the scoop clean. Clean it by using a neutral cleaner and rinse thoroughly.

• Clean the bin liner by using a neutral cleaner. Rinse thoroughly after cleaning.

3. Air Filters (air-cooled models only)

The plastic mesh air filters located behind the louvers remove dirt or dust from the air,

and keep the condenser from getting clogged. As the filters get clogged, the icemaker’s

performance will be reduced. Check the filters at least twice a month. When they are

clogged, use warm water and a neutral cleaner to wash the filters.

4. Condenser (air-cooled and remote air-cooled models only)

Check the condenser once a year, and clean if required by using a brush or vacuum

cleaner. More frequent cleaning may be required depending on the location of the

icemaker or condenser unit.

C. Preparing the Icemaker for Long Storage

WARNING

When shutting off the icemaker for an extended time, drain out all water from

the water tank and remove the ice from the storage bin. The storage bin should

be cleaned and dried. Drain the icemaker to prevent damage to the water

supply line at sub-freezing temperatures, using air or carbon dioxide. Shut off

the icemaker until the proper ambient temperature is resumed.

When the icemaker is not used for two or three days, it is sufficient to only move the control

switch to the "OFF" position, unless the icemaker will be at sub-freezing temperatures.

1. On water-cooled model only, first remove the water from the water-cooled condenser:

1) Remove the front panel.

2) Move the control switch on the control box to the "OFF" position.

3) Wait 3 minutes.

4) Move the control switch to the "ICE" position.

5) Allow 5 minutes for the icemaker to fill with water and the water pump to start operating.

6) Close the water-cooled condenser water supply line shut-off valve.

7) Open the drain valve for the water-cooled condenser water supply line.

8) Allow the line to drain by gravity.

9) Attach compressed air or carbon dioxide supply to the condenser water line drain valve.

10) Quickly blow the water-cooled condenser out, using compressed air or carbon dioxide

until water stops coming out.

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2. Remove the water from the potable water supply line:

1) Remove the front panel (except water-cooled model).

2) Move the control switch on the control box to the "OFF" position.

3) Wait 3 minutes.

4) Close the potable water supply line shut-off valve and open the potable water supply

line drain valve.

5) Allow the line to drain by gravity.

6) Attach compressed air or carbon dioxide supply to the potable water line drain valve.

7) Move the control switch to the "ICE" position.

8) Blow the potable water line out using compressed air or carbon dioxide.

3. Drain the potable water tank:

1) Turn off the power supply.

2) Move the control switch to the "OFF" position.

3) Drain the water tank by removing the base

cover and one end of the pump tubing. See

Fig. 5.

4) Replace the pump tubing and the base

cover in their correct positions.

5) Remove all ice from the storage bin, and

clean the storage bin.

6) Replace the front panel in its correct position.

7) Close the drain valve.

Fig. 5