Hoshizaki KM-151BAH User Manual

NO. M006-749

ISSUED: FEB. 18, 2008

REVISED: JUN. 12, 2008

HOSHIZAKI

SELF-CONTAINED

CRESCENT CUBER

MODEL

KM-61BAH

KM-101BAH
KM-151BAH

SERVICE MANUAL

IMPORTANT

Only qualified service technicians should attempt to install, service, or
maintain this product. 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 qualified service technicians in the
service and maintenance of the product.

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.

HOSHIZAKI AMERICA, INC.
618 Highway 74 South
Peachtree City, GA 30269

Attn: HOSHIZAKI Technical Support Department

Phone: [phone] Technical Service
[phone]
Fax: [phone]
[phone]
E-mail: [e-mail]

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 qualified 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. SPECIFICATIONS -------------------------------------------------------------------------------------1

1. SPECIFICATIONS ----------------------------------------------------------------------------------1
[a] KM-61BAH ---------------------------------------------------------------------------------------1
[b] KM-101BAH -------------------------------------------------------------------------------------2
[c] KM-151BAH -------------------------------------------------------------------------------------3

II. GENERAL INFORMATION -------------------------------------------------------------------------4

1. CONSTRUCTION ----------------------------------------------------------------------------------4
[a] KM-61BAH, KM-101BAH ---------------------------------------------------------------------4
[b] KM-151BAH -------------------------------------------------------------------------------------5
[c] ICEMAKING COMPARTMENT -------------------------------------------------------------6

2. SEQUENCE OF OPERATION ------------------------------------------------------------------7
[a] ONE MINUTE FILL CYCLE ------------------------------------------------------------------7
[b] INITIAL HARVEST CYCLE ------------------------------------------------------------------7
[c] FREEZE CYCLE -------------------------------------------------------------------------------7
[d] DRAIN CYCLE ---------------------------------------------------------------------------------- 8
[e] NORMAL HARVEST CYCLE --------------------------------------------------------------- 8

3. CONTROL BOARD ------------------------------------------------------------------------------ 10
[a] CONTROL BOARD LAYOUT ------------------------------------------------------------- 11
[b] FEATURES ------------------------------------------------------------------------------------ 12
[c] CONTROLS AND ADJUSTMENTS ------------------------------------------------------ 14
[d] CONTROL BOARD CHECK PROCEDURE------------------------------------------- 16
[e] CONTROL BOARD REPLACEMENT --------------------------------------------------- 17

4. HARVEST CONTROL - THERMISTOR ---------------------------------------------------- 17

5. BIN CONTROL ------------------------------------------------------------------------------------ 18
[a] EXPLANATION OF OPERATION -------------------------------------------------------- 18
[b] BIN CONTROL CHECK PROCEDURE ------------------------------------------------ 18

6. SWITCHES ---------------------------------------------------------------------------------------- 19

PAGE

III. TECHNICAL INFORMATION -------------------------------------------------------------------- 20

1. WATER CIRCUIT AND REFRIGERANT CIRCUIT --------------------------------------- 20
[a] KM-61BAH, KM-101BAH ------------------------------------------------------------------- 20
[b] KM-151BAH ----------------------------------------------------------------------------------- 21

2. WIRING DIAGRAM ------------------------------------------------------------------------------ 22
[a] KM-61BAH ------------------------------------------------------------------------------------- 22

i

[b] KM-101BAH ----------------------------------------------------------------------------------- 23
[c] KM-151BAH ----------------------------------------------------------------------------------- 24

3. TIMING CHART ----------------------------------------------------------------------------------- 25

4. PERFORMANCE DATA ------------------------------------------------------------------------- 26

[a] KM-61BAH ------------------------------------------------------------------------------------- 26
[b] KM-101BAH ----------------------------------------------------------------------------------- 27
[c] KM-151BAH ----------------------------------------------------------------------------------- 28

IV. SERVICE DIAGNOSIS ---------------------------------------------------------------------------- 29

1. 10-MINUTE DIAGNOSTIC PROCEDURE ------------------------------------------------- 29

2. NO ICE PRODUCTION ------------------------------------------------------------------------- 31

3. EVAPORATOR IS FROZEN UP -------------------------------------------------------------- 34

4. LOW ICE PRODUCTION ----------------------------------------------------------------------- 35

5. ABNORMAL ICE ---------------------------------------------------------------------------------- 35

6. OTHER ---------------------------------------------------------------------------------------------- 36

V. REMOVAL AND REPLACEMENT -------------------------------------------------------------- 37

1. SERVICE FOR REFRIGERANT LINES ---------------------------------------------------- 37

[a] SERVICE INFORMATION ----------------------------------------------------------------- 37
[b] REFRIGERANT RECOVERY ------------------------------------------------------------- 38
[c] EVACUATION AND RECHARGE -------------------------------------------------------- 38

2. BRAZING ------------------------------------------------------------------------------------------- 39

3. COMPRESSOR ----------------------------------------------------------------------------------- 40

4. DRIER ----------------------------------------------------------------------------------------------- 41

5. HOT GAS VALVE --------------------------------------------------------------------------------- 42

6. EXPANSION VALVE - KM-151BAH ONLY ------------------------------------------------- 44

7. FAN MOTOR --------------------------------------------------------------------------------------- 46

8. PUMP MOTOR ------------------------------------------------------------------------------------ 47

9. WATER VALVE ------------------------------------------------------------------------------------ 48

10. CLEANING VALVE ------------------------------------------------------------------------------- 49

11. DRAIN VALVE ------------------------------------------------------------------------------------- 50

12. FLOAT SWITCH ---------------------------------------------------------------------------------- 51
[a] KM-61BAH, KM-101BAH ------------------------------------------------------------------- 51
[b] KM-151BAH ----------------------------------------------------------------------------------- 52

13. BIN CONTROL SWITCH ----------------------------------------------------------------------- 53

14. THERMISTOR ------------------------------------------------------------------------------------ 56

15. CONTROL BOX ---------------------------------------------------------------------------------- 57
[a] POWER SWITCH ---------------------------------------------------------------------------- 58
[b] FUSE -------------------------------------------------------------------------------------------- 58
[c] FUSE HOLDER ------------------------------------------------------------------------------- 58
[d] CONTROLLER BOARD -------------------------------------------------------------------- 58
[e] POWER RELAY ------------------------------------------------------------------------------ 58
[f] COMPRESSOR CAPACITOR - KM-101BAH, KM-151BAH ONLY -------------- 59
[g] CONTROLLER BOARD TRANSFORMER -------------------------------------------- 59

16. WATER TANK ------------------------------------------------------------------------------------- 59

17. CUBE GUIDE ------------------------------------------------------------------------------------- 61

18. SEPARATOR -------------------------------------------------------------------------------------- 62

ii

19. SPRAY TUBE, WATER SUPPLY PIPE, SPRAY GUIDE ------------------------------- 62

20. DOOR ----------------------------------------------------------------------------------------------- 63

VI. CLEANING AND MAINTENANCE INSTRUCTIONS -------------------------------------- 64

1. CLEANING ----------------------------------------------------------------------------------------- 64
[a] CLEANING PROCEDURE ----------------------------------------------------------------- 64
[b] SANITIZING PROCEDURE --------------------------------------------------------------- 66

2. MAINTENANCE ---------------------------------------------------------------------------------- 67
[a] EXTERIOR PANELS ------------------------------------------------------------------------ 67
[b] STORAGE BIN AND SCOOP ------------------------------------------------------------- 67
[c] AIR FILTER ------------------------------------------------------------------------------------ 67
[d] CONDENSER --------------------------------------------------------------------------------- 67

3. PREPARING THE ICEMAKER FOR LONG STORAGE -------------------------------- 67

iii

I. SPECIFICATIONS

1. SPECIFICATIONS

[a] KM-61BAH

AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 3.4A ( 5 Min. Freeze AT 104°F / WT 80°F )
MINIMUM CIRCUIT AMPASITY 15A
MAXIMUM FUSE SIZE 15A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *71 (32) 65 (29) 58 (26)
Reference without *marks 80 66 (30) 56 (25) 51 (23)

90 65 (29) *49 (22) 43 (20)

100 64 (29) 48 (22) *38 (17)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 1.7 lbs. (0.75 kg) , 80 pcs.
APPROXIMATE STORAGE CAPACITY 38 lbs. (17 kg)
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 210(10.5) 220(7.4)
WATER gal./24HR (gal./100 lbs.) 10(20.3) 23(32.0)
EXTERIOR DIMENSIONS (WxDxH) 17.75" x 24" x 39" (450 x 610 x 990 mm)

Including 6" legs
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 92 lbs. (42 kg), Shipping 117 lbs. (53 kg)
CONNECTIONS - ELECTRIC Cord Connection

- WATER SUPPLY Inlet 1/2" FPT

- DRAIN Outlet 3/4" FPT
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 Mechanical Level Switch with Delay
COMPRESSOR Hermetic, Model QA51K13GAU6-E0GS
CONDENSER Air-Cooled, Fin and tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Capillary Tube
REFRIGERANT CHARGE R134a, 6.4 oz. (180g)
DESIGN PRESSURE High 250PSIG, Low 150PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED Ice Scoop, 6" leg 4 pcs
ACCESSORIES -REQUIRED N/A
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V

AMBIENT TEMP. 45-100

WATER SUPPLY TEMP. 45- 90

WATER SUPPLY PRESSURE 10-113 PSIG

㐈
㐈

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

1

[b] KM-101BAH

AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 5.2A ( 5 Min. Freeze AT 104㐈 / WT 80㐈 )
MINIMUM CIRCUIT AMPASITY 15A
MAXIMUM FUSE SIZE 15A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *115 (52) 107 (49) 97 (44)
Reference without *marks 80 109 (50) 97 (44) 87 (40)

90 107 (49) *88 (40) 78 (35)

100 106 (48) 86 (39) *69 (31)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 2.31 lbs. (1.05 kg) , 110 pcs.
APPROXIMATE STORAGE CAPACITY 53 lbs. (24 kg)
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 340(9.4) 330(6.8)
WATER gal./24HR (gal./100 lbs.) 20(23.0) 47(40.9)
EXTERIOR DIMENSIONS (WxDxH) 23.75" x 24" x 39" (603 x 610 x 990 mm)

Including 6" legs
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 106 lbs. (48 kg), Shipping 136 lbs. (62 kg)
CONNECTIONS - ELECTRIC Cord Connection

- WATER SUPPLY Inlet 1/2" FPT

- DRAIN Outlet 3/4" FPT
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 Mechanical Level Switch with Delay
COMPRESSOR Hermetic, Model QA91K22CAU6-E0GS
CONDENSER Air-Cooled, Fin and tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Capillary Tube
REFRIGERANT CHARGE R134a, 7.8 oz. (220g)
DESIGN PRESSURE High 250PSIG, Low 150PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED Ice Scoop, 6" leg 4 pcs
ACCESSORIES -REQUIRED N/A
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V

AMBIENT TEMP. 45-100

WATER SUPPLY TEMP. 45- 90

WATER SUPPLY PRESSURE 10-113 PSIG

㐈
㐈

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

2

[c] KM-151BAH

AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 7.0A ( 5 Min. Freeze AT 104㐈 / WT 80㐈 )
MINIMUM CIRCUIT AMPASITY 15A
MAXIMUM FUSE SIZE 15A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *146 (66) 139 (63) 129 (58)
Reference without *marks 80 140 (64) 129 (59) 119 (54)

90 139 (63) *121 (55) 111 (50)

100 137 (62) 119 (54) *101 (46)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 2.75 lbs. (1.25 kg) , 130 pcs.
APPROXIMATE STORAGE CAPACITY 78 lbs. (36 kg)
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 420(8.4) 390(6.4)
WATER gal./24HR (gal./100 lbs.) 22(17.8) 50(34.5)
EXTERIOR DIMENSIONS (WxDxH) 23.75" x 28" x 39" (603 x 712 x 990 mm)

Including 6" legs
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 117 lbs. (53 kg), Shipping 150 lbs. (68 kg)
CONNECTIONS - ELECTRIC Cord Connection

- WATER SUPPLY Inlet 1/2" FPT

- DRAIN Outlet 3/4" FPT
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 Mechanical Level Switch with Delay
COMPRESSOR Hermetic, Model QA125K29CAU6-E0GS
CONDENSER Air-Cooled, Fin and tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
REFRIGERANT CHARGE R134a, 8.5 oz. (240g)
DESIGN PRESSURE High 250PSIG, Low 150PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED Ice Scoop, 6" leg 4 pcs
ACCESSORIES -REQUIRED N/A
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V

AMBIENT TEMP. 45-100

WATER SUPPLY TEMP. 45- 90

WATER SUPPLY PRESSURE 10-113 PSIG

㐈
㐈

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

3

II. GENERAL INFORMATION

1. CONSTRUCTION

[a] KM-61BAH, KM-101BAH

Top Panel Separator Spray Tube

Evaporator

Door Water Supply
Tube
Front Panel
Tank
Louver

Control Box

Control Switch

Condenser
Fan Motor
Hot Gas Valve Air Filter

Front View

Thermistor

Cleaning
Valve

Water
Valve

Rear Panel Pump
Motor

Power
Supply
Pipe Cover Cord

Drain Valve

Drier Compressor

Rear Cover

Float Switch

Rear View

With Tank Removed

Bin Control Switch

4

[b] KM-151BAH

Top Panel Separator Spray Tube

Evaporator

Door Water Supply
Tube
Front Panel
Tank
Louver

Control Box

Control
Switch

Condenser
Compressor
Hot Gas Valve Air Filter

Front View

Fan Motor

Thermistor

Cleaning
Valve

Water
Valve

Rear Panel Pump Expansion Valve
Motor

Power
Supply
Pipe Cover Cord Drier

Drain Valve

Rear Cover

Float Switch

Rear View

Bin Control Switch

With Tank Removed

5

[c] ICEMAKING COMPARTMENT

Water Valve

Cleaning Valve

Spray Tube Water Supply Pipe Evaporator

Pump Motor

Separator

Cube Guide

Float Switch

Water Tank

6

2. 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 5, 6, 8, 4, 7.

[a] ONE MINUTE FILL CYCLE

LED 8 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.

[b] INITIAL HARVEST CYCLE

LEDs 5, 6, and 8 are on. WV remains open, Comp energizes, 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 (S1 dip switch 1 & 2). 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. WV is open during harvest for a maximum of 6 minutes or the length of
harvest minus 0, 10, 30, or 50 seconds (adjustable by S1 dip switch 7 & 8), whichever is
shorter. LED 8 goes off when WV closes. PM energizes and runs for the last 0, 10, 30,
or 50 seconds of harvest depending on S1 dip switch 7 & 8 setting. LED 7 comes on
when PM energizes. 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 fill if it is open.

[c] FREEZE CYCLE

LEDs 5 & 7 are on. Comp continues to run, PM and FMS energize, HGV closes and
the freeze cycle starts. For the first 5 minutes after the thermistor temperature reaches
36°F (2°C), the control board will not accept a signal from F/S. This minimum freeze
period acts as a short cycle protection. At the end of this period, F/S assumes control.
As the evaporator cools, the thermistor located on the suction line checks for a 34°F (1°C)
temperature. When 34°F (1°C) is reached, a 5.8 kΩ signal causes the control board to
de-energize the pump motor for 10 seconds. This is to prevent slushing. As ice builds
on the evaporator the water level in the sump lowers. The freeze continues until F/S
opens and terminates ice production.

7

[d] DRAIN CYCLE

LEDs 4, 5, and 6 are on. Comp continues to run, HGV opens, and FMS de-energizes.
PM stops. DV opens for 20 seconds to drain out the water tank. Drain cycle always
occurs on the 2nd harvest after startup. Then, depending on the control board setting,
drain cycle occurs every cycle, or every 2nd, 5th, or 10th cycle (S1 dip switch 5 & 6).

[e] NORMAL HARVEST CYCLE

LEDs 5, 6, and 8 are on. Comp continues 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. WV is open during
harvest for a maximum of 6 minutes or the length of harvest minus 0, 10, 30, or 50
seconds (adjustable by S1 dip switch 7 & 8), whichever is shorter. LED 8 goes off when
WV closes. PM energizes and runs for the last 0, 10, 30, or 50 seconds of harvest
depending on S1 dip switch 7 & 8 setting. LED 7 comes on when PM energizes. 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 fill if it is open.
The unit continues to cycle through [c], [d], and [e] sequence until the bin control is
activated and shuts the unit down. When the bin control is activated, the "POWER OK"
LED flashes.

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

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

8

9

3. CONTROL BOARD

* A HOSHIZAKI exclusive solid-state control is employed in KM-61BAH, KM-101BAH

and KM-151BAH 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 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.

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

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

10

[a] CONTROL BOARD LAYOUT

Connector K7
Transformer

"H" Control Board

Relay LEDs (6)
(indicate which relays
are energized as
listed below)

LED 5 (X1 Relay)
Compressor (Comp)
Remote Fan Motor
(FMR)

Connector K3
Magnetic Contactor

Connector K4
Open

POWER OK LED
(Lights when power is
supplied to the board.
Flashes when bin control
is activated.)

Connector K5
Pins
#1 Fan Motor
#2 Hot Gas Valve
#3 Pump Motor
#4 Water Valve
#5 Open
#6 Drain Valve

Connector K6
Open

Connector K1
Pins
#1, 3 Float Switch
#2 Open
#4, 5 Bin Control
#6, 7 Thermistor
#8, 9 Open

LED 6 (X2 Relay)
Hot Gas Valve (HGV)
Self-Contained Fan
Motor (FMS) (FMS off
when LED on)

LED 8 (X4 Relay)
Inlet Water Valve (WV)
(Harvest Water Valve
(HWV) on units with
two inlet water valves)

LED 9 (X5 Relay)
Freeze Water Valve
(FWV) on units with
two inlet water valves
(service board only)

LED 4 (X6 Relay)
Drain Valve (DV)

LED 7 (X3 Relay)
Pump Motor (PM)

Connector K8
Open

Output Test Button
(used to test relays on
board)

Connector K2
Open

Alarm Buzzer S1 Dip Switch S2 Dip Switch Alarm Reset Button
(service board only)

Control Board

Part Number

Type HKM2006V003

P00013-03 (factory)

P00013-02 (service)

11

[b] 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
minus 0, 10, 30, or 50 seconds (adjustable by S1 dip switch 7 & 8), 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 specified to complete. The control board will signal this
problem using 3 beeps every 3 seconds. The time is factory set using S1 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°F ± 7°F (53°C ± 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 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 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 next 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 next cycle. The unit will not start without adequate water in the
sump. This serves as a low water safety to protect the water pump.
For water-cooled model, if the condenser water supply 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

12

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.

f) LED Lights and Audible Alarm Safeties

The control board includes LED indicator lights, audible alarm safeties, and an output
test feature. The "POWER OK" LED indicates control voltage and will remain on unless
a control voltage problem occurs. The “POWER OK” LED flashes continuously when
the bin is full and DV energizes for a maximum of 5 minutes to drain the water tank.
At startup, a 5 second delay occurs to stabilize the circuit. LEDs 4 through 8 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 5, 6, 8, 4, 7. For more information, see "2.
SEQUENCE OF OPERATION".

Sequence Step LED

1 Minute Fill Cycle

Harvest Cycle 5, 6, 8

Last 0, 10, 30, or 50 seconds (adjustable by dip switch) of harvest, WV de-energizes
and PM energizes (LEDs 5, 6, and 7 are on)

Freeze Cycle 5, 7

Drain 5, 6, 4

8 WV 60 seconds

Energized

Components

WV, HGV,
Comp

Comp, PM,
FMS
Comp, HGV,
DV

Min. Max. Avg.

2 minutes 20 minutes 3 to 5 minutes

5 minutes

10 seconds 20 seconds

Time LEDs are On

freeze timer
setting

30 to 35 minutes

factory default
setting

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

No. of Beeps

(every 3 sec.)

High Evaporator Temp.

1

2

3

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

(temperature > 127
(53
Harvest Backup Timer
(harvest > 20 min. for two
cycles in a row)
Freeze Timer
(freeze > specified setting
for two cycles in a row)
Timer is factory set using
S1 dip switch 9 & 10

Type of Alarm Notes

Check for harvest problem (stuck HGV or

°F)

°C)

relay), hot water entering unit, stuck HM, or
shorted thermistor.
Check for open thermistor, HGV not
opening, TXV leaking by, low charge,
inefficient Comp, or WRV leaking by.
Check for a float switch stuck closed (up),
WV leaking by, HGV leaking by, PM not
pumping, TXV not feeding properly, low
charge, or inefficient Comp.

13

6

7

Legend:

Low Voltage
(92Vac

± 5% or less)

High Voltage
(147Vac

± 5% or more)

Comp–compressor; DV–drain valve; FMS–self-contained fan motor; HGV–hot

"POWER OK" LED will turn off if voltage
protection operates.
The control voltage safeties automaticlly
reset when voltage is corrected.

gas valve; PM–pump motor; TXV–thermostatic expansion valve; WRV–water
regulating valve; WV–inlet water valve

[c] CONTROLS AND ADJUSTMENTS

a) Default Dip Switch Settings

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

S1 Dip Switch No. 1 2 3 4 5 6 7 8 9 10

KM-61BAH
KM-151BAH

KM-101BAH

OFF OFF ON ON ON ON OFF ON OFF ON

ON OFF ON ON ON ON OFF ON OFF ON

If the S2 dip switch is mounted on the control board, all should be left in the “OFF”
position.

S1 Dip Switch

Freeze Timer (9 & 10)

Water Saver Timer (7 & 8)

Drain Frequency Control (5 & 6)

Drain Timer (3 & 4)

Harvest Timer (1 & 2)

Fig. 1

b) Harvest Timer (S1 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

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longer setting will decrease 24 hour production.

Dip Switch Setting
No. 1 No. 2

OFF OFF 60

ON OFF 90

OFF ON 120

ON ON 180

c) Drain Timer (S1 dip switch 3 & 4)

Once every ten freeze cycles, the drain valve opens to drain the water tank for the
time determined by the drain timer. These switches also determine the time to delay
completion of a defrost cycle, i.e. the minimum defrost time.
Do not change this setting, or the unit will not operate properly or produce high quality
ice.

Dip Switch Setting Time (seconds)
No. 3 No. 4 T1 T2

OFF OFF 10 120

ON OFF 10 180

OFF ON 20 120

ON ON 20 180

Time

(seconds)

T1: Time to drain the water tank
T2: Harvest timer at drain

Drain cycle always occurs on the 2nd harvest after startup. Then, depending on the
drain frequency control setting (dip switch 5 & 6), drain cycle occurs every cycle, or
every 2nd, 5th, or 10th cycle.

d) Drain Frequency Control (S1 dip switch 5 & 6)

The water tank drains at the frequency set by the drain frequency control.
The drain 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 drain more often, the drain frequency can be adjusted as shown in the table
below.

Dip Switch Setting
No. 5 No. 6

OFF OFF every cycle

ON OFF every 2 cycles

OFF ON every 5 cycles

ON ON every 10 cycles

Frequency

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e) Water Saver Timer (S1 dip switch 7 & 8)

The water saver timer allows the water valve to close and the pump motor to circulate
water in the tank during the final part of harvest. The water valve is open during harvest
for a maximum of 6 minutes or the length of harvest minus 0, 10, 30, or 50 seconds
(determined by the water saver timer setting), whichever is shorter. When the water
valve closes, the pump motor energizes and runs for the time determined by the water
saver timer setting.
The water saver timer is factory-adjusted, and no adjustment is required.

Dip Switch Setting
No. 7 No. 8

OFF OFF 0

ON OFF 10

OFF ON 30

ON ON 50

f) Freeze Timer (S1 dip switch 9 & 10)

Time

(seconds)

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
No. 9 No. 10

OFF OFF 60

ON OFF 50

OFF ON 70

ON ON 60

Time

(minutes)

[d] 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 S1 dip switch 3, 4, 7, 8, 9, & 10 are in the
factory default position. S1 dip switch 1, 2, 5, & 6 are cleaning adjustments and the
settings are flexible.

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2) Move the control switch to the “ICE” position and check for proper control voltage. If

the “POWER OK” LED is on, the control voltage is good. If the “POWER OK” LED
is off, check the control transformer circuit. If no voltage is present, check the power
supply circuit.

3) To perform a relay sequence test, turn on the power switch while pressing the

"OUTPUT TEST" button. The correct lighting sequence should be 5, 6, 7, 8, 4.
Some components (e.g., the compressor) will cycle during test. Each LED comes on
for 5 seconds. LED 5 is on while LED 6 is on. Following the output test sequence,
the icemaker will resume normal operation beginning with the 1 minute fill cycle.

[e] CONTROL BOARD REPLACEMENT

The dip switches should be adjusted to the factory default settings as outlined in this
manual. S2 dip switch 5 must remain off.

4. HARVEST CONTROL - THERMISTOR

A thermistor (semiconductor) is used as a harvest control sensor and anti-slush sensor.
The resistance varies depending on the suction line temperatures. The thermistor
detects the temperature of the evaporator outlet to start the harvest timer or momentarily
stop the pump motor during the freeze cycle. 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
90 32 1.633

Check a thermistor for resistance by using the following procedure:

1) Disconnect the connector K1 on the board.

2) Remove the thermistor. See “V. 14. THERMISTOR”.

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

4) Check for resistance between the thermistor leads. Normal reading is within 3.5 to 7
kΩ. Replace the thermistor if it exceeds the normal reading.

21 2.474

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5. BIN CONTROL

This machine uses a lever-actuated proximity switch (mechanical bin control) to control
the ice level in the storage bin. No adjustment is required.

[a] EXPLANATION OF OPERATION

The bin control is connected to the K1 connector (pins 4 & 5) on the control board.
When the bin control is calling for ice (proximity switch closed; "POWER OK" LED on),
the control board continues icemaking operations. When the bin control is activated
in the bin full position (proximity switch open; "POWER OK" LED flashing), the control
board drains and shuts down the unit. However, to prevent incomplete batches of
ice from forming on the evaporator, the control board will only shut down the machine
during the freeze cycle before the five minute timer expires. The five minute timer starts
counting down when the thermistor temperature reaches 36°F (2°C). If, during the
freeze cycle, ice pushes in the lever after the five minute timer expires, the control board
will allow the machine to complete the freeze cycle and the following harvest cycle
before shutting down the machine.

[b] BIN CONTROL CHECK PROCEDURE

1) Clear any ice away from the bin control.

2) Make sure the control switch is in the "ICE" position.

3) Check that the "POWER OK" LED on the control
board is on.

4) Activate the bin control actuator (press the actuator
in). Check that the "POWER OK" LED flashes.

5) Disconnect the bin control at the 2-pin connector
attached to the black wires (located in the circle in
Fig. 2) coming from the K1 connector (pins 4 & 5) on
the control board.

6) Check for continuity across the bin control leads.
When calling for ice, the bin control proximity switch
should be closed. If open, replace the bin control.
Activate the bin control actuator (press the actuator
in), check for continuity across the bin control leads.
The bin control proximity switch should be open. If
closed, replace the bin control.

Fig. 2

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