Hoshizaki KML-351MAH User manual

Hoshizaki
“A Superior Degree
of Reliability”
www.hoshizaki.com
Models
KML-351MAH
KML-351MWH
Low-Profile Modular Crescent Cuber
Hoshizaki America, Inc.
SERVICE MANUAL
™
Number: 73149
Issued: 6-10-2008

2
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: [phone] Technical Service
[phone]
Fax: [phone]
[phone]
E-mail: [email protected]
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
CONTENTS
I. Specications...................................................................................................................... 6
A. Icemaker ....................................................................................................................... 6
1a. KML-351MAH (air-cooled) (auxiliary code: S-0) .................................................... 6
1b. KML-351MAH (air-cooled) (auxiliary codes: T-0 and later)..................................... 7
2. KML-351MWH (water-cooled).................................................................................. 8
II. General Information ........................................................................................................... 9
A. Construction.................................................................................................................. 9
1a. KML-351MAH (air-cooled) (auxiliary code: S-0) .................................................... 9
1b. KML-351MAH (air-cooled) (auxiliary codes: T-0 and later)................................... 10
2. KML-351MWH (water-cooled).................................................................................11
B. Sequence of Operation ............................................................................................... 12
1. One Minute Fill Cycle ............................................................................................. 12
2. Initial Harvest Cycle .............................................................................................. 12
3. Freeze Cycle ......................................................................................................... 12
4. Pump-Out Cycle ................................................................................................... 12
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 Timer (dip switch 1 & 2)...................................................................... 19
c) Pump-Out Timer (dip switch 3 & 4) .................................................................. 20
d) Pump-Out Frequency Control (dip switch 5 & 6).............................................. 20
e) Factory Use (dip switch 7 & 8) ......................................................................... 20
f) Freeze Timer (dip switch 9 & 10)....................................................................... 21
4. Control Board Check Procedure ............................................................................ 21
5. Control Board Replacement .................................................................................. 21
D. Harvest Control – Thermistor ...................................................................................... 22
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.

4
E. Bin Control .................................................................................................................. 22
F. Switches....................................................................................................................... 22
1. Control Switch ........................................................................................................ 22
2. Service Switch....................................................................................................... 22
a) DRAIN.............................................................................................................. 23
b) CIRCULATE..................................................................................................... 23
c) WASH............................................................................................................... 23
III. Technical Information ...................................................................................................... 24
A. Water Circuit and Refrigeration Circuit ........................................................................ 24
1. KML-351MAH (air-cooled)...................................................................................... 24
2. KML-351MWH (water-cooled)................................................................................ 25
B. Wiring Diagrams.......................................................................................................... 26
1a. KML-351MAH (air-cooled) (auxiliary code: S-0) and
KML-351MWH (water-cooled) (all auxiliary codes).............................................. 26
1b. KML-351MAH (air-cooled) (auxiliary codes: T-0 and later) .................................. 27
C. Performance Data ....................................................................................................... 28
1a. KML-351MAH (air-cooled) (auxiliary code: S-0) .................................................. 28
1b. KML-351MAH (air-cooled) (auxiliary codes: T-0 and later)................................... 29
2. KML-351MWH (water-cooled)................................................................................ 30
IV. Service Diagnosis ........................................................................................................... 31
A. 10-Minute Diagnostic Procedure ................................................................................ 31
B. Diagnostic Charts........................................................................................................ 33
1. No Ice Production................................................................................................... 33
2. Evaporator is Frozen Up ........................................................................................ 36
3. Low Ice Production ................................................................................................ 38
4. Abnormal Ice ......................................................................................................... 39
5. Other...................................................................................................................... 40
V. Removal and Replacement of Components .................................................................... 41
A. Service for Refrigerant Lines....................................................................................... 41
1. Refrigerant Recovery ............................................................................................. 41
2. Brazing .................................................................................................................. 41
3. Evacuation and Recharge (R-404A)...................................................................... 42
B. Removal and Replacement of Compressor................................................................. 43
C. Removal and Replacement of Expansion Valve.......................................................... 44
D. Removal and Replacement of Hot Gas Valve or Liquid Line Valve ............................ 45
E. Removal and Replacement of Evaporator................................................................... 46
F. Removal and Replacement of Self-Contained Air-Cooled Condenser ......................... 46
G. Removal and Replacement of Water-Cooled Condenser............................................ 47
H. Removal and Replacement of Water Regulating Valve - Water-Cooled Model Only ... 48
I. Adjustment of Water Regulating Valve - Water-Cooled Model Only .............................. 49
J. Removal and Replacement of Thermistor.................................................................... 50
K. Removal and Replacement of Fan Motor - Air-Cooled Models Only ........................... 50
L. Removal and Replacement of Water Valves ................................................................ 51
M. Removal and Replacement of Pump Motor ................................................................ 51

5
VI. Cleaning and Maintenance Instructions ......................................................................... 52
A. Cleaning and Sanitizing Procedures ........................................................................... 52
1. Cleaning Procedure................................................................................................ 52
2. Sanitizing Procedure – Following Cleaning Procedure .......................................... 53
B. Maintenance................................................................................................................ 54
C. Preparing the Icemaker for Long Storage ................................................................... 54

6
I. Specications
A. Icemaker
1a. KML-351MAH (air-cooled) (auxiliary code: S-0)
Note: We reserve the right to make changes in specications and design without prior
notice.
AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 8.8 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 *334 (152) 312 (142) 291 (132)
Reference without *marks 80 317 (144) 284 (129) 268 (121)
90 312 (142) *260 (118) 241 (109)
100 311 (141) 256 (116) 224 (102)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 6.8 lbs. (3.1 kg) 360 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 820(7.6) 770(5.5)
WATER gal./24HR (gal./100 lbs.) 62(24.0) 113(33.7)
EXTERIOR DIMENSIONS (WxDxH) 30" x 27 3/8" x 22" (762 x 695 x 559 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 154 lbs. (70 kg), Shipping 185 lbs. (84 kg)
CONNECTIONS - ELECTRIC Permanent - 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 Thermostat
COMPRESSOR Hermetic, Model ASE32C3E-CAA-254
CONDENSER Air-Cooled, Fin and tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
REFRIGERANT CHARGE R404A, 1 lb. 5 oz. (596g)
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

7
1b. KML-351MAH (air-cooled) (auxiliary codes: T-0 and later)
Note: We reserve the right to make changes in specications and design without prior
notice.
AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 13.2 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY 20 A
MAXIMUM FUSE SIZE 20 A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *350 (159) 342 (155) 309 (140)
Reference without *marks 80 344 (156) 331 (150) 287 (130)
90 342 (155) *322 (146) 282 (128)
100 328 (149) 313 (142) 245 (111)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 7.3 lbs. (3.3 kg) 360 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 993 (7.4) 802 (5.5)
WATER gal./24HR (gal./100 lbs.) 79 (24.6) 170 (48.5)
EXTERIOR DIMENSIONS (WxDxH) 30" x 27-3/8" x 22" (762 x 695 x 559 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 154 lbs. ( 70 kg ), Shipping 185 lbs. (84 kg)
CONNECTIONS - ELECTRIC Permanent - 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 Thermostat
COMPRESSOR Hermetic, Model RS43C2E-CAA-219
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. 2 oz. ( 505 g )
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
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
2. KML-351MWH (water-cooled)
Note: We reserve the right to make changes in specications and design without prior
notice.
AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 7.5 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 *345 (156) 340 (154) 318 (144)
Reference without *marks 80 341 (155) 333 (151) 303 (137)
90 340 (154) *327 (148) 300 (136)
100 330 (150) 321 (145) 275 (125)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 7.1 lbs. (3.2 kg) 360 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 720(5.3) 710(4.9)
WATER gal./24HR (gal./100 lbs.) 67(20.4) 124(35.9)
WATER COOLED CONDENSER 428(131) 273(79)
gal./24HR (gal./100 lbs.)
EXTERIOR DIMENSIONS (WxDxH) 30" x 27 3/8" x 22" (762 x 695 x 559 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 154 lbs. (70 kg), Shipping 185 lbs. (84 kg)
CONNECTIONS - ELECTRIC Permanent - Connection
- WATER SUPPLY Inlet 1/2" FPT Condenser Inlet 1/2" FPT
- DRAIN Outlet 3/4" FPT Condenser Outlet 3/8" 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 Water Regulator
BIN CONTROL SYSTEM Thermostat
COMPRESSOR Hermetic, Model ASE32C3E-CAA-254
CONDENSER Water-cooled, Tube in tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
REFRIGERANT CHARGE R-404A, 1 lb. 1.6 oz. (500g)
DESIGN PRESSURE High 427PSIG, 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

9
II. General Information
A. Construction
1a. KML-351MAH (air-cooled) (auxiliary code: S-0)
Spray Tubes
Water Supply
Inlet
Junction Box
Condenser
Condenser
Fan Motor
Control Box
Drier
Hot Gas Valve
Compressor
Float Switch
Water Pump
Bin Control
Thermostat
Control
Switches
Expansion
Valve
Inlet Water
Valve
Drain Valve
Wash Valve
Liquid Line
Valve

10
1b. KML-351MAH (air-cooled) (auxiliary codes: T-0 and later)
Spray Tubes
Water Supply
Inlet
Junction Box
Condenser
Condenser
Fan Motor
Control Box
Drier
Hot Gas Valve
Compressor
Float Switch
Water Pump
Bin Control
Thermostat
Control
Switches
Expansion
Valve
Inlet Water
Valve
Drain Valve
Wash Valve

11
2. KML-351MWH (water-cooled)
Water
Regulator
Water Supply
Inlet
Junction Box
Condenser
Control Box
Drier
Hot Gas
Valve
Compressor
Float Switch
Water Pump
Control
Switches
Expansion
Valve
Spray Tubes
Drain Valve
Wash Valve
Inlet Water
Valve
Liquid Line
Valve
Bin Control
Thermostat
Auxiliary Code S-0
Auxiliary Codes
T-0 and later

12
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 control 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 control 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, FMR, 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 (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
(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 and FMR continue to run, PM and FMS energize, LLV opens, 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 and FMR continue to run, HGV opens, LLV closes, and
FMS de-energizes. PM stops for 2 seconds. SR energizes, restarting PM and taking
water from the sump and forcing it to go through DV and down the drain. When the
pump-out timer (dip switch 3 & 4) stops counting, the pump out is complete.
The 1st pump out occurs after the 1st freeze cycle and every 10th cycle thereafter. The
pump-out frequency control (dip switch 5 & 6) 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 out more often, the pump-out frequency can be adjusted.
The pump-out frequency control (dip switch 5 & 6) can be set to have a pump out occur
every cycle, or every 2, 5, or 10 cycles. See "II.C.3.d) Pump-Out Frequency Control (dip
switch 5 & 6)."

13
5. Normal Harvest Cycle
LEDs 1, 4, and 2 are on. Comp and FMR remain energized, FMS de-energizes and
HGV and WV 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 (dip switch 1 & 2) which is factory set for normal
conditions. The harvest timer has settings of 60, 90, 120, and 180 seconds. For
further details, see "II.C.3.b) Harvest Timer (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; DV–drain valve; FMR–remote fan motor;
FMS–self-contained fan motor; F/S–oat switch; HGV–hot gas valve;
LLV –liquid line valve; PM–pump motor; SR–service relay; WV–inlet water valve

14
KML-351MAH and KML-351MWH 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 LLV de-energized
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 LLV energized
F/S closed
Freeze cycle operation turned over to F/S
PM stops for 2 sec., SR energizes, starting PM & DV for 10/20 sec. each 1, 2, 5, or 10 cycles. Comp continues FMR continues HGV energized FMS de-energized LLV 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" control board will have 5 second delay
If F/S is open, compressor stops and cycle returns to 1 minute ll
Legend: Comp–compressor DV–drain valve FMR–remote fan motor FMS–self-contained fan motor F/S–oat switch HGV–hot gas valve LLV –liquid line valve PM–pump motor SR–service relay WV–inlet water valve
Components Energized when the Control Switch is in the "SERVICE" Position When in the "SERVICE" position, the control switch supplies power to the service switch and the unit is in service mode. The service switch has three positions: "DRAIN," "CIRCULATE," and "WASH." See the information below for details of each function.
DRAIN Power is supplied to the pump and drain valve. This drains the water tank. CIRCULATE Power is supplied to the pump only. This operation can be used to circulate cleaner for
extended periods of time over the outside surface of the evaporator.
WASH Power is supplied to the pump and wash valve. This operation is used to circulate cleaner
and sanitizer over both the inside and outside surfaces of the evaporator.

15
C. Control Board
•A Hoshizaki exclusive solid-state control is employed in KML-351MAH and
KML-351MWH Modular Crescent Cubers.
•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 control board.
3. Do not touch the electronic devices on the control board or the back of the
control board to prevent damage.
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 control board assembly if it goes bad.
6. Do not short out power supply to test for voltage.

16
"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 Liquid Line Valve
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)
"ALARM RESET" Switch
Freeze Timer LED
Dip Switch
Harvest Backup
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
Inlet Water Valve (WV)
LED 1
Compressor (Comp)
Remote Fan Motor
(FMR)
Transformer
Connector
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

17
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 dip switches 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 one
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 next cycle. If the oat switch is in the down position (electrical circuit open),
the control board changes to additional one 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 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 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 control 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 control 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 Comp, FMR,
WV, HGV
2 minutes 20 minutes 3 to 5 minutes
Freeze Cycle 1 Comp, FMR/
FMS, PM,
LLV
5 minutes freeze timer
setting
30 to 35 minutes
Pump Out Cycle 1, 4*, 3, and
2
Comp, FMR,
WV*, PM,
HGV, SR,
DV
10 seconds 20 seconds *pump-out timer
setting
The built in safeties shut down the unit and have alarms as listed below.
No. of Beeps
(every 3 sec.) Type of Alarm Notes
1High Evaporator Temp.
(temperature > 127°F)
(53°C)
Check for harvest problem (stuck HGV or
relay), hot water entering unit, stuck HM, or
shorted thermistor.
2Harvest 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
Comp.
3Freeze Timer
(freeze > specied setting
for two cycles in a row)
Timer is factory set using
dip switch 9 & 10
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, HM not
bypassing, or inefficient Comp.
To reset the above safeties, press the "ALARM RESET" button with the power supply on.
6Low Voltage
(92Vac ±5% or less)
Red LED will turn off if voltage protection
operates.
The control voltage safeties automatically
reset when voltage is corrected.
7High Voltage
(147Vac ±5% or more)
Legend: Comp–compressor; DV–drain valve; FMR–remote fan motor; FMS–self-
contained fan motor; F/S–oat switch; HGV–hot gas valve; HM–headmaster
(C.P.R.); LLV –liquid line valve; PM–pump motor; SR–service relay;
TXV–thermostatic expansion valve; WV–inlet water valve

19
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 Dip Switch Settings
The dip switches are factory-adjusted to the following positions:
Model
Auxiliary
Code
Dip Switch No.
12345678910
KML-351MAH S-0 ON OFF ON ON OFF OFF OFF OFF OFF ON
T-0 and later OFF OFF OFF ON ON ON OFF OFF OFF ON
KML-351MWH All ON OFF ON ON OFF OFF OFF OFF OFF ON
Freeze Timer (9 & 10)
Pump-Out Frequency Control (5 & 6)
Pump-Out Timer (3 & 4)
Harvest Timer (1 & 2)
Normally off (7 & 8)
b) 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 setting. 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.
Dip Switch Setting Time
(seconds)
No. 1 No. 2
OFF OFF 60
ON OFF 90
OFF ON 120
ON ON 180

20
c) 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) Inlet
Water
ValveNo. 3 No. 4 T1 T2
OFF OFF 10 150 closed
ON OFF 10 180 closed
OFF ON 10 120 open
ON ON 20 180 closed
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.
d) 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 generally required. However, where water quality is
bad and the icemaker needs a pump out 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
e) Factory Use (dip switch 7 & 8)
Factory set for optimum performance. Do not adjust.