Hoshizaki American, Inc. KM-600MAH Service Manual

Hoshizaki America, Inc.

Hoshizaki

Modular Crescent Cuber

Model KM-600MAH

“A Superior Degree

of Reliability”

www.hoshizaki.com

SERVICE MANUAL

™

Number: 73167 Issued: 8-12-2008 Revised: 8-25-2008

IMPORTANT

Only qualied service technicians should attempt to install, service, or maintain this icemaker. No service or maintenance should be undertaken until the technician has thoroughly read this Service Manual. Failure to service and maintain the equipment in accordance with this manual may adversely affect safety, performance, and warranty coverage.

Hoshizaki provides this manual primarily to assist qualied 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, write, or send an e-mail message 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 E-mail: techsupport@hoshizaki.com

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.

IMPORTANT

This manual should be read carefully before the icemaker is serviced or maintenance operations are performed. Only qualied service technicians should install, service, and maintain the icemaker. Read the warnings contained in this booklet carefully as they give important information regarding safety. Please retain this booklet for any further reference that may be necessary.

CONTENTS

I. Specications ..................................................................................................................... 5

II. General Information ........................................................................................................... 6

A. Construction .................................................................................................................. 6

B. Sequence of Operation ................................................................................................. 7

1. One Minute Fill Cycle .............................................................................................. 7

2. Initial Harvest Cycle ................................................................................................ 7

3. Freeze Cycle .......................................................................................................... 7

4. Pump-Out Cycle ..................................................................................................... 7

5. Normal Harvest Cycle ............................................................................................ 8

C. Control Board ............................................................................................................. 10

1. Control Board Layout ............................................................................................ 11

2. Features ................................................................................................................ 12

a) Maximum Water Supply Period – 6 minutes ...................................................... 12

b) Harvest Backup Timer and Freeze Timer .......................................................... 12

c) High Temperature Safety ................................................................................... 12

d) Low Water Safety ............................................................................................... 12

e) High Voltage and Low Voltage Cut-outs ............................................................ 12

f) LED Lights and Audible Alarm Safeties .............................................................. 13

3. Controls and Adjustments ..................................................................................... 14

a) Default S4 Dip Switch Settings ........................................................................... 14

b) Harvest Timer (S4 dip switch 1 & 2) ................................................................... 14

c) Pump-Out Timer (S4 dip switch 3 & 4) ............................................................... 15

d) Pump-Out Frequency Control (S4 dip switch 5 & 6) .......................................... 15

e) Factory Use (S4 dip switch 7 & 8) ...................................................................... 15

f) Freeze Timer (S4 dip switch 9 & 10) ................................................................... 16

4. Control Board Check Procedure ........................................................................... 16

5. Control Board Replacement .................................................................................. 17

D. Harvest Control – Thermistor...................................................................................... 17

1. Thermistor Check .................................................................................................. 17

E. Float Switch ................................................................................................................ 17

1. Float Switch Check ................................................................................................ 17

2. Float Switch Cleaning ............................................................................................ 18

F. Bin Control .................................................................................................................. 19

III. Technical Information ..................................................................................................... 20

A. Water Circuit and Refrigeration Circuit ....................................................................... 20

B. Wiring Diagram ........................................................................................................... 21

C. Performance Data ...................................................................................................... 22

IV. Service Diagnosis .......................................................................................................... 23

A. 10-Minute KM Diagnostic Procedure ......................................................................... 23

B. Diagnostic Charts ....................................................................................................... 25

1. No Ice Production .................................................................................................. 25

2. Evaporator is Frozen Up ....................................................................................... 28

3. Low Ice Production ................................................................................................ 29

4. Abnormal Ice ......................................................................................................... 30

5. Other ..................................................................................................................... 30

V. Removal and Replacement of Components ................................................................... 32

A. Service for Refrigerant Lines ...................................................................................... 32

1. Refrigerant Recovery ............................................................................................ 32

2. Brazing .................................................................................................................. 32

3. Evacuation and Recharge (R-404A) ..................................................................... 33

B. Removal and Replacement of Compressor ................................................................ 34

C. Removal and Replacement of Expansion Valve......................................................... 35

D. Removal and Replacement of Hot Gas Valve ........................................................... 36

E. Removal and Replacement of Evaporator .................................................................. 37

F. Removal and Replacement of Thermistor................................................................... 38

G. Removal and Replacement of Fan Motor ................................................................... 39

H. Removal and Replacement of Inlet Water Valve ........................................................ 39

I. Removal and Replacement of Pump Motor ................................................................. 40

VI. Cleaning and Maintenance ........................................................................................... 41

A. Cleaning and Sanitizing Instructions ........................................................................... 41

1. Cleaning Procedure ............................................................................................... 42

2. Sanitizing Procedure - Following Cleaning Procedure .......................................... 43

B. Maintenance ............................................................................................................... 44

C. Preparing the Icemaker for Long Storage .................................................................. 44

I. Specications

AC SUPPLY VOLTAGE 115-120/60/1 AMPERAGE 12.0 A ( 5 Min. Freeze AT 104°F / WT 80°F) MINIMUM CIRCUIT AMPACITY 15 A MAXIMUM FUSE SIZE 15 A APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F) PER 24 HR. Temp.(°F) 50 70 90 lbs./day ( kg/day ) 70 *592 (269) 566 (257) 516 (234) Reference without *marks 80 572 (260) 532 (241) 474 (215)

90 566 (257) *503 (228) 447 (203)

100 551 (250) 490 (222) 396 (180) SHAPE OF ICE Crescent Cube ICE PRODUCTION PER CYCLE 14.3 lbs. (6.5 kg) 720 pcs. APPROXIMATE STORAGE CAPACITY N/A ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F ELECTRIC W (kWH/100 lbs.) 1190(5.7) 1040(4.2) WATER gal./24HR (gal./100 lbs.) 99(19.7) 259(43.7) CEC/CEE TIER LEVEL 2 ENERGY STAR YES EXTERIOR DIMENSIONS (WxDxH) 22" x 27-3/8" x 37-7/16" (560 x 695 x 950 mm) EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear) WEIGHT Net 169 lbs. (77 kg), Shipping 200 lbs. (91 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 RST55C1E-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. 11 oz. (765g) DESIGN PRESSURE High 467PSIG, Low 230PSIG 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

A. Icemaker

KM-600MAH (air-cooled)

Note: We reserve the right to make changes in specications and design without prior

notice.

II. General Information

A. Construction

1. KM-600MAH (air-cooled)

Bin Control Thermostat

Control Switch

Expansion Valve

Spray Tubes

Water Supply Pipe

Condenser

Control Box

Fan Motor

Float Switch

Hot Gas Valve

Drier

Compressor

Water Pump

B. Sequence of Operation

The steps in the sequence are as outlined below. When power is supplied, the red "POWER OK" LED on the control board comes on. 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 ll 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 PM.

2. Initial Harvest Cycle

LEDs 1, 4, and 2 are on. WV remains open, Comp and HGV energize. The control board monitors the warming of the evaporator via the thermistor located on the suction line. When the thermistor reaches 48°F (9°C), the control board reads a 3.9 kΩ signal from the thermistor and turns harvest termination over to the adjustable harvest timer (S4 dip switch 1 & 2) which is factory set for normal conditions. The harvest timer has settings of 60, 90, 120, and 180 seconds. For details, see "II.C.3.b) Harvest Timer (S4 dip switch 1 & 2)." When the harvest timer completes its countdown, the harvest cycle is complete and the freeze cycle starts. The minimum total time allowed by the control board for a complete harvest cycle is 2 minutes. WV is energized during harvest for a maximum of 6 minutes or the length of harvest, whichever is shorter. At the end of harvest, the control board checks the position of F/S and proceeds to the freeze cycle if it is closed or calls for a 1-minute ll if it is open.

3. Freeze Cycle

LED 1 is on. Comp continues to run, PM and FMS energize, HGV and WV close, and the freeze cycle starts. For the rst 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 continues to run, HGV opens, and FMS de-energizes. 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 ows through the small tube to power ush the F/S. When the pump-out timer (S4 dip switch 3 & 4) stops counting, the pump out is complete. The 1st pump out occurs after the 1st freeze cycle. The pump-out frequency control (S4 dip switch 5 & 6) is factory-adjusted to drain the water tank every 10th cycle thereafter, and no adjustment is required. However, where water quality is bad and the icemaker needs a pump out more often, the pump-out frequency control (S4 dip switch 5 & 6) can be set to have a pump out occur every cycle, or every 2, 5, or 10 cycles. For details, see "II.C.3.d) Pump-Out Frequency Control (S4 dip switch 5 & 6)."

5. Normal Harvest Cycle

LEDs 1, 4, and 2 are on. Comp and HGV remain energized. PM stops and WV energizes. The control board monitors the warming of the evaporator via the thermistor located on the suction line. When the thermistor reaches 48°F (9°C), the control board reads a 3.9 kΩ signal from the thermistor and turns harvest termination over to the adjustable harvest timer (S4 dip switch 1 & 2) which is factory set for normal conditions. The harvest timer has settings of 60, 90, 120, and 180 seconds. For details, see "II. C.3.b) Harvest Timer (S4 Dip Switch 1 & 2)." When the harvest timer completes its countdown, the harvest cycle is complete and the freeze cycle starts. The minimum total time allowed by the control board for a complete harvest cycle is 2 minutes. WV is energized during harvest for a maximum of 6 minutes or the length of harvest, whichever is shorter. At the end of harvest, the control board checks the position of F/S and proceeds to the freeze cycle if it is closed or calls for a 1-minute ll if it is open.

Legend: Comp–compressor; FMS–self-contained fan motor; F/S–ﬂoat switch;

HGV–hot gas valve; PM–pump motor; WV–inlet water valve

Cycle

Pump motor stops

for 2 sec. and then

reverses for 10/20 sec.

each 1, 2, 5, or 10 cycles.

Comp continues

HGV energized

4. Pump-Out

F/S in

control

Freeze cycle

operation turned

over to F/S

5 minute timer

in control

F/S closed

Comp continues

HGV de-energized

WV de-energized

• Minimum freeze time: 5 minutes

• Maximum freeze time: freeze timer setting

F/S Check

PM energized

FMS de-energized

FMS energized

F/S open

1 to 3 minute timer

in control

2. Harvest Cycle 3. Freeze Cycle

Thermistor in

• Maximum inlet water valve time: 6 minutes

control

• Maximum harvest time: 20 minutes

Thermistor temp

reaches 48°F (9°C)

F/S closed

Comp energized

HGV energized

(3.9 kΩ or less)

Harvest timer starts

WV continues

Components Energized when the Control Switch is in the "WASH" Position

The "WASH" position on the control switch is used when cleaning and sanitizing the unit. When in the

"WASH" position, power is supplied to the pump motor. With the cleaning valve closed, the cleaner and

sanitizer ow over the outside of the evaporator plate assembly. With the cleaning valve open, the cleaner

and sanitizer ow over both the outside and the inside of the evaporator plate assembly.

Note: Close the cleaning valve after cleaning and sanitizing are complete, otherwise the unit will not re-start

when the control switch is placed in the "ICE" position.

KM-600MAH Sequence Flow Chart and Component Operation

F/S open

Fill Cycle

1. One Minute

Cycle Steps

F/S Check

WV Energized

"E" board will have

Initial startup always

5 second delay

begins here

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

Legend:

Comp-compressor

FMS-self-contained fan motor

F/S-oat switch

HGV-hot gas valve

PM-pump motor

WV-inlet water valve

C. Control Board

• A Hoshizaki exclusive solid-state control is employed in the KM-600MAH Modular Crescent Cuber.

• All models are pretested and factory-adjusted.

CAUTION

1. Fragile, handle very carefully.

2. The 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 before 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 oat 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.

1. Control Board Layout

Control Products "E" Control Board

"ALARM RESET" Switch

Backup Freeze Timer LED

Backup Harvest Timer LED

Alarm Buzzer

S4 Dip Switch

"OUTPUT TEST" Switch (used to test relays on board)

Connector K3 Harvest Control (thermistor)

Connector K4 Open (not connected)

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 Inlet Water Valve (WV)

LED 1 Compressor (Comp)

Transformer Connector

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 Self-Contained Fan Motor (FMS) #4 Pump Motor (icemaking) #5 Pump Motor (pump out) #6 Inlet Water Valve #7, 10 Power Supply #8 Open

Switch for "C" board and "ALPINE" board (service boards only)

Control Board

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

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

2. Features

a) Maximum Water Supply Period – 6 minutes

The inlet water valve will be open during harvest for 6 minutes or the length of harvest whichever is shorter.

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 specied to complete. The control board will signal this problem using 3 beeps every 3 seconds. The time is factory set using S4 dip switch 9 & 10. The "ALARM 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 control board reads a .804 kΩ signal from the thermistor and 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 "ALARM RESET" button on the control board must be pressed with power on to reset the safety.

d) Low Water Safety

The control board checks the position of the oat switch at the end of the initial 1 minute water ll cycle and at the end of each harvest cycle. If the oat switch is in the up position (electrical circuit closed), the control board changes to the ice making cycle. If the oat switch is in the down position (electrical circuit open), the control board changes to additional 1 minute water ll cycles until water enters the sump and the oat switch closes. When the oat 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.

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 insufcient 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.

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 beep occurs when the power 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

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

Freeze Cycle 1 Comp, PM,

Pump-Out Cycle 1, 4*, 3, and 2Comp, HGV,

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

No. of Beeps

(every 3 sec.)

1 High Evaporator Temp.

2 Harvest Backup Timer

4 WV 60 seconds

Type of Alarm Notes

(temperature > 127°F) (53°C)

(harvest > 20 min. for two cycles in a row)

Energized

Components

Comp

FMS

PM, WV*

Check for harvest problem (stuck HGV or relay), hot water entering unit, or shorted thermistor.

Orange LED marked H TIMER lights up. Check for open thermistor, HGV not opening, TXV leaking by, low charge, or inefﬁcient Comp.

Min. Max. Avg.

2 minutes 20 minutes 3 to 5 minutes

5 minutes freeze timer

10 seconds 20 seconds *pump-out timer

Time LEDs are On

setting

30 to 35 minutes

setting

3 Freeze Timer

(freeze > speciﬁed setting for two cycles in a row) Timer is factory set using S4 dip switch 9 & 10

To reset the above safeties, press the "ALARM RESET" button with the power supply on.

6 Low Voltage

(92Vac ±5% or less)

7 High Voltage

(147Vac ±5% or more)

Legend: Comp–compressor; FMS–self-contained fan motor; F/S–ﬂoat switch;

HGV

–hot gas valve; PM–pump motor; TXV–thermostatic expansion valve;

WV–inlet water valve

Yellow LED marked F TIMER lights up. Check for F/S stuck closed (up), WV leaking by, HGV leaking by, PM not pumping, TXV not feeding properly, low charge, or inefﬁcient Comp.

Red LED will turn off if voltage protection operates. The control voltage safeties automatically reset when voltage is corrected.

3. Controls and Adjustments

CAUTION

Dip switches are factory set. Failure to maintain factory settings may adversely affect performance and warranty coverage. For more information, contact Hoshizaki Technical Support at 1-800-233-1940.

a) Default S4 Dip Switch Settings

The dip switches are factory-adjusted to the following positions:

S4 Dip Switch No. 1 2 3 4 5 6 7 8 9 10

KM-600MAH

OFF OFF OFF OFF ON ON OFF OFF OFF OFF

Freeze Timer (9 & 10)

Normally off (7 & 8)

Pump-Out Frequency Control (5 & 6) Do Not Adjust

Pump-Out Timer (3 & 4)

Harvest Timer (1 & 2)

b) Harvest Timer (S4 dip switch 1 & 2)

The harvest timer starts counting when the thermistor reaches 48°F (9°C) at the evaporator outlet and the control board reads the thermistor's 3.9 kΩ signal. The harvest timer is factory-adjusted, and no adjustment is required. However, a setting longer than the factory setting may be advised in cases where the ush provided at harvest needs to be prolonged for extra cleaning. Before changing this setting, contact Hoshizaki Technical Support at 1-800-233-1940 for recommendations. Keep in mind that setting the harvest timer to a longer setting will decrease 24 hour production. Note that the pump-out timer (S4 dip switch 3 & 4) acts in place of the harvest timer during cycles with a pump out

S4 Dip Switch Setting Time

No. 1 No. 2

OFF OFF 60

ON OFF 90

OFF ON 120

ON ON 180

(seconds)

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