Hoshizaki
“A Superior Degree
of Reliability”
www.hoshizaki.com
Models
KM-320MAH
KM-320MWH
Modular Crescent Cuber
Hoshizaki America, Inc.
Number: 73132
Issued: 1-24-2006
Revised: 11-30-2006
SERVICE MANUAL
IMPORTANT
Only qualified service technicians should attempt to service or maintain this
icemaker. No such service or maintenance should be undertaken until the
technician has thoroughly read this Service Manual.
HOSHIZAKI provides this manual primarily to assist qualified service technicians in the
service and maintenance of the icemaker.
Should the reader have any questions or concerns which have not been satisfactorily
addressed, please call or write to the HOSHIZAKI Technical Support Department for
assistance.
HOSHIZAKI AMERICA, INC.
618 Highway 74 South
Peachtree City, GA 30269
Attn: HOSHIZAKI Technical Support Department
Phone: 1-800-233-1940 Technical Service
(770) 487-2331
Fax: 1-800-843-1056
(770) 487-3360
Web Site: www.hoshizaki.com
NOTE: To expedite assistance, all correspondence/communication MUST include the
following information:
• Model Number
• Serial Number
• Complete and detailed explanation of the problem
2
Please review this manual. It should be read carefully before the icemaker is serviced or
maintenance operations are performed. Only qualified service technicians should service
and maintain the icemaker. This manual should be made available to the technician prior to
service or maintenance.
CONTENTS
I. Specifications ...................................................................................................................... 5
A. KM-320MAH (air-cooled) .............................................................................................. 5
B. KM-320MWH (water-cooled) ......................................................................................... 6
II. General Information ........................................................................................................... 7
A. Construction .................................................................................................................. 7
1. KM-320MAH (air-cooled) ......................................................................................... 7
2. KM-320MWH (water-cooled) ................................................................................... 8
B. Controller Board ............................................................................................................ 9
1. Solid-State Control .................................................................................................. 9
2. Controller Board ...................................................................................................... 9
3. Sequence .............................................................................................................. 13
4. Controls and Adjustments .................................................................................... 16
5. Checking the Controller Board .............................................................................. 19
III. Technical Information ...................................................................................................... 21
A. Water Circuit and Refrigerant Circuit ........................................................................... 21
1. KM-320MAH .......................................................................................................... 21
2. KM-320MWH ......................................................................................................... 22
B. Wiring Diagram ............................................................................................................ 23
1. KM-320MAH, KM-320MWH .................................................................................. 23
C. Timing Chart .............................................................................................................. 24
D. Performance Data ....................................................................................................... 26
1. KM-320MAH .......................................................................................................... 26
2. KM-320MWH ......................................................................................................... 27
IV. Service Diagnosis ........................................................................................................... 28
A. No Ice Production........................................................................................................ 28
B. Evaporator is Frozen Up.............................................................................................. 31
C. Low Ice Production ..................................................................................................... 33
D. Abnormal Ice ............................................................................................................... 33
E. Other ........................................................................................................................... 33
V. Removal and Replacement of Components .................................................................... 34
A. Service for Refrigerant Lines ...................................................................................... 34
1. Refrigerant Recovery ............................................................................................. 34
2. Evacuation and Recharge (R-404A) ...................................................................... 34
B. Brazing ........................................................................................................................ 35
C. Removal and Replacement of Compressor ................................................................ 36
D. Removal and Replacement of Drier ............................................................................ 37
E. Removal and Replacement of Expansion Valve .......................................................... 37
F. Removal and Replacement of Hot Gas Valve and Line Valve ...................................... 38
G. Removal and Replacement of Evaporator .................................................................. 39
H. Removal and Replacement of Thermistor ................................................................... 40
I. Removal and Replacement of Fan Motor ..................................................................... 41
J. Removal and Replacement of Water Valve .................................................................. 41
3
K. Removal and Replacement of Pump Motor ................................................................ 42
L. Removal and Replacement of Spray Tubes ................................................................. 42
M. Removal and Replacement of Water Regulating Valve – Water-Cooled Model Only .
N. Adjustment Of Water Regulating Valve – Water-Cooled Model Only .......................... 44
VI. Cleaning and Maintenance Instructions ......................................................................... 45
A. Preparing the Icemaker for Long Storage ................................................................... 45
B. Cleaning and Sanitizing Instructions ........................................................................... 47
1. Cleaning Procedure ............................................................................................... 48
2. Sanitizing Procedure - Following Cleaning Procedure ..........................................
C. Maintenance ............................................................................................................... 50
43
49
4
I. Specifications
SPECIFICATION NO. 05A013 ISSUED: 11/29/2005
ITEM: HOSHIZAKI MODULAR CRESCENT CUBER
MODEL: KM-320MAH
AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 9.7 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY 20 A
MAXIMUM FUSE SIZE 20 A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *325 (147) 311 (141) 287 (130)
Reference without *marks 80 315 (143) 293 (133) 265 (120)
90 311 (141) *278 (126) 251 (114)
100 304 (138) 272 (123) 226 (103)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 7.2 lbs. (3.3 kg) 360 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 800(6.9) 750(5.5)
WATER gal./24HR (gal./100 lbs.) 51(18.4) 117(35.9)
EXTERIOR DIMENSIONS (WxDxH) 22" x 27-3/8" x 30-5/16" (560 x 695 x 770 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 123 lbs. (56 kg), Shipping 153 lbs. (70 kg)
CONNECTIONS - ELECTRIC Permanent - Connection
- WATER SUPPLY Inlet 1/2" FPT
- DRAIN Outlet 3/4" FPT
3/8" OD Tube
CUBE CONTROL SYSTEM Float Switch
HARVESTING CONTROL SYSTEM Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL Timer Controlled. Overflow Pipe
COOLING WATER CONTROL N/A
BIN CONTROL SYSTEM Thermostat
COMPRESSOR Hermetic, Model ASE32C3E-CAA
CONDENSER Air-Cooled , Fin and tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
REFRIGERANT CHARGE R-404A, 1 lb. 4.3 oz. (575g)
DESIGN PRESSURE High 467PSIG, Low 210PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
REFRIGERANT CIRCUIT PROTECTION Auto-reset High Pressure Control Switch
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED N/A
-REQUIRED Ice Storage Bin
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V
AMBIENT TEMP. 45 -100° F
WATER SUPPLY TEMP. 45 - 90° F
WATER SUPPLY PRESSURE 10 - 113 PSIG
A. KM-320MAH (air-cooled)
Note: We reserve the right to make changes in specifications and design without prior
notice.
5
AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 8.2 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY 20 A
MAXIMUM FUSE SIZE 20 A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *352 (160) 348 (158) 324 (147)
Reference without *marks 80 349 (158) 342 (155) 309 (140)
90 348 (158) *337 (153) 308 (140)
100 337 (153) 330 (150) 281 (127)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 7.2 lbs. (3.3 kg) 360 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 730(5.2) 730(5.0)
WATER gal./24HR (gal./100 lbs.) 57(16.8) 103(29.4)
WATER COOLED CONDENSER 528(157) 327(93)
gal./24HR (gal./100 lbs.)
EXTERIOR DIMENSIONS (WxDxH) 22" x 27-3/8" x 30-5/16" (560 x 695 x 770 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 123 lbs. (56 kg), Shipping 153 lbs. (70 kg)
CONNECTIONS - ELECTRIC Permanent - Connection
- WATER SUPPLY Inlet 1/2" FPT
- DRAIN Outlet 3/4" FPT
3/8" OD Tube
CUBE CONTROL SYSTEM Float Switch
HARVESTING CONTROL SYSTEM Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL Timer Controlled. Overflow Pipe
COOLING WATER CONTROL Pressure Regulator
BIN CONTROL SYSTEM Thermostat
COMPRESSOR Hermetic, Model ASE32C3E-CAA
CONDENSER Water-cooled, Tube in tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
REFRIGERANT CHARGE R-404A, 1 lb. 0.8 oz. (486g)
DESIGN PRESSURE High 427PSIG, Low 210PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
REFRIGERANT CIRCUIT PROTECTION Auto-reset High Pressure Control Switch
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED N/A
-REQUIRED Ice Storage Bin
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V
AMBIENT TEMP. 45 -100° F
WATER SUPPLY TEMP. 45 - 90° F
WATER SUPPLY PRESSURE 10 - 113 PSIG
B. KM-320MWH (water-cooled)
Note: We reserve the right to make changes in specifications and design without prior
notice.
6
II. General Information
A. Construction
1. KM-320MAH (air-cooled)
Evaporator
Cleaning Valve
Bin Control
Thermostat
Spray Tubes
Expansion Valve
Control Switch
Water Supply Inlet
Hot Gas Valve
Condenser
Fan Motor
Float Switch
Water Pump
Drier
Compressor
Control Box
(shown transparent to allow view
of other components)
7
2. KM-320MWH (water-cooled)
Evaporator
Cleaning Valve
Bin Control
Thermostat
Spray Tubes
Expansion Valve
Control Switch
Water Supply Inlet
Hot Gas Valve
Water Regulator
Condenser
Float Switch
Water Pump
Drier
Compressor
Control Box
(shown transparent to allow view
of other components)
8
B. Controller Board
1. Solid-State Control
• A HOSHIZAKI exclusive solid-state control is employed in KM-320MAH and
KM-320MWH Modular Crescent Cubers.
• A printed circuit board (hereafter called "controller board") includes a stable and high
quality control system.
• All models are pretested and factory-adjusted.
2. Controller Board
CAUTION
1. Fragile, handle very carefully.
2. A controller board contains integrated circuits, which are susceptible to
failure due to static discharge. It is especially important to touch the metal
part of the unit when handling or replacing the board.
3. Do not touch the electronic devices on the board or the back of the board to
prevent damage to the board.
4. Do not change wiring and connections. Do not misconnect K3, K4 and K5,
because the same connector is used for the thermistor and float switch. K4 is
not connected.
5. Always replace the whole board assembly when it goes bad.
6. Do not short out power supply to test for voltage.
Controller Board
Part Number Type
2A1410-01
Features of Control Products "E" Controller Board
a) Maximum Water Supply Period - 6 minutes
Water solenoid valve opening, in the defrost (harvest) cycle, is limited by the defrost
timer. The water valve cannot remain open longer than the maximum period. The water
valve can close in less than six minutes if the defrost cycle is completed.
b) Defrost Timer
The defrost cycle starts when the float switch opens and completes the freeze cycle.
But the defrost timer does not start counting until the thermistor senses 48°F (9°C) at
the evaporator outlet. The period from the end of the freeze cycle up to the point of the
thermistor’s sensing varies depending on the ambient and water temperatures.
HOS-001A (Control Products - 10 Pin)
9
c) High Temperature Safety - 127 ± 7°F (53 ± 4°C)
The temperature of the suction line in the refrigerant circuit is limited by the high
temperature safety.
During the defrost cycle the evaporator temperature rises. The thermistor senses
48°F (9°C) and starts the defrost timer. After the defrost timer counts down to zero,
the normal freeze cycle begins. If the evaporator temperature continues to rise, the
thermistor will sense the rise in temperature and at 127 ± 7°F (53 ± 4°C) the thermistor
operates the high temperature safety.
This high temperature safety shuts down the circuit and the icemaker automatically
stops.
This high temperature safety protects the unit from excessive temperature. The control
board will beep every 3 seconds. The white reset button on the control board must be
pressed with power on to reset the safety.
d) Low Water Safety
If the pump motor is operated without water, the mechanical seal can fail. To prevent
this type of failure, the controller board checks the position of the float switch at the end
of the initial one minute water fill cycle and at the end of each defrost cycle.
If the float switch is in the up position (electrical circuit closed), the controller board
changes to the ice making cycle. If the float switch is in the down position (electrical
circuit open), the controller board changes to a one minute water fill cycle before
starting the ice making cycle. This method allows for a low water safety shut down to
protect the water pump from mechanical seal failure.
For water-cooled model, if the water is shut off, the unit is protected by the high
pressure switch.
e) High Voltage Cut-out
The maximum allowable supply voltage of this icemaker is limited by the high voltage
cut-out.
If miswiring (especially on single phase 3 wire models) causes excessive voltage on
the controller board, the high voltage cut-out shuts down the circuit in 3 seconds and
the icemaker automatically stops. When the proper supply voltage is resumed, the
icemaker automatically starts running again. The control board will signal this problem
using 7 beeps every 3 seconds.
f) LED Lights and Audible Alarm Safeties
The red LED indicates proper control voltage and will remain on unless a control
voltage problem occurs. At startup a 5 second delay occurs while the board conducts
an internal timer check. A short beep occurs when the power switch is turned ON or
OFF.
10
The green LEDs 1-4 represent the corresponding relays and energize and sequence
5 seconds from initial startup as follows:
Sequence Step LED
Min. Max. Avg.
1 Minute Fill Cycle 4 60 seconds
Harvest Cycle 1, 4, and 2 2 minutes 20 minutes 3 to 5 minutes
Freeze Cycle 1 5 minutes 60 minutes 30 to 35 minutes
Reverse Pump Out 1, 3, and 2 10 seconds 20 seconds factory setting
{LED 1 – Comp; LED 2 - HGV/CFM; LED 3 – PM; LED 4 - WV}
The built in safeties shut down the unit and have alarms as follows:
No. of Beeps
(every 3 sec.)
1 High Evaporator Temp.
2 Defrost Backup Timer
Type of Alarm Notes
Check for defrost problem (stuck HGV
(temperature > 127°F)
(53°C)
(defrost > 20 min.)
or relay), hot water entering unit, stuck
headmaster, or shorted thermistor.
Orange LED marked H TIMER lights up.
Check for open thermistor, HGV not
opening, TXV leaking by, low charge, or
inefficient compressor.
Time LEDs are Lit
3 Freeze Backup Timer
(freeze > 60 min.)
To manually reset the above safeties, press the white alarm reset button with the
power supply on.
6 Low Voltage
(92Vac or less)
7 High Voltage
(control voltage
> 147Vac ±5%)
The output test switch "S3" provides a relay sequence test. With power OFF, place S3
ON and switch power to ICE. The correct lighting sequence should be none, 2, 3, 4, 1, &
4, normal sequence every 5 seconds. S3 should remain in the "OFF" position for normal
operation.
Yellow LED marked F TIMER lights up.
Check for F/S stuck closed (up), WV
leaking by, HGV leaking by, TXV not
feeding properly, low charge, or inefficient
compressor.
Red LED will turn off if voltage protection
operates.
The voltage safety automatically resets
when voltage is corrected.
11
The application switch located between relay X3 & X4 must be set to match the original
board application. Place this switch in the ALP position if there is no white wire supplied to
the K1 connector. If there is a white wire, place the switch in the C position. If this switch is
placed in the wrong position either the compressor contactor will remain energized with the
control switch OFF or the unit will not start.
The dip switches should be adjusted per the adjustment chart published in the Tech Specs
book. 7 & 8 must remain in the OFF position.
(Control Products HOS-001A Board)
12
3. Sequence
1st Cycle
1. Unit energized and control switch to "ICE"
position. Water supply cycle starts.
2. After 1 minute, defrost
cycle starts.
Water Valve
3. Thermistor reads 48°F (9°C).
Defrost timer starts counting.
Water Valve
Hot Gas Valve
Defrost
Cycle
Freeze
Cycle
Pump, Fan &
Line Valve
5. After the first 5 minutes in freeze cycle.
Ready to complete freeze cycle when float
switch circuit opens.
IMPORTANT
Board never accepts freeze completion signal
within the first 5 minutes in freeze cycle.
Defrost Timer
IMPORTANT
Water valve opening is
limited to 6 minutes.
4. Defrost timer stops counting.
Defrost cycle is completed and
freeze cycle starts.
IMPORTANT
1. Board never accepts defrost completion signal
within the first 2 minutes in defrost cycle.
2. Defrost cycle time is limited to 20 minutes even
if defrost timer does not stop counting.
13
2nd Cycle and after with pump drain
IMPORTANT
Freeze cycle time is limited by the freeze timer
factory setting even if the float switch does not
open.
1. Float switch opens and signals to complete
freeze cycle. Drain timer starts counting.
Drain Pump
Hot Gas Valve
2. Drain timer stops counting.
Pump drain is completed.
Defrost
Cycle
Water Valve
3. Thermistor reads 48°F (9°C).
Defrost timer starts counting.
Freeze
Cycle
Pump, Fan &
Line Valve
5. After the first 5 minutes in freeze cycle.
Ready to complete freeze cycle when float
switch circuit opens.
IMPORTANT
Board never accepts freeze completion signal
within the first 5 minutes in freeze cycle.
IMPORTANT
Water valve opening is
Defrost Timer
limited to 6 minutes.
4. Defrost timer stops counting.
Defrost cycle is completed and
freeze cycle starts.
IMPORTANT
1. Board never accepts defrost completion signal
within the first 2 minutes in defrost cycle.
2. Defrost cycle time is limited to 20 minutes even
if defrost timer does not stop counting.
14
2nd Cycle and after with no pump drain
IMPORTANT
Freeze cycle time is limited by the freeze timer
factory setting even if the float switch does not
open.
1. Float switch opens and signals to complete
freeze cycle.
Water Valve
Hot Gas Valve
Defrost
Cycle
Freeze
Cycle
2. Thermistor reads 48°F (9°C).
Defrost timer starts counting.
Defrost Timer
Pump, Fan &
Line Valve
4. After the first 5 minutes in freeze cycle.
Ready to complete freeze cycle when float
switch circuit opens.
IMPORTANT
Board never accepts freeze completion signal
within the first 5 minutes in freeze cycle.
IMPORTANT
Water valve opening is
limited to 6 minutes.
3. Defrost timer stops counting.
Defrost cycle is completed and
freeze cycle starts.
IMPORTANT
1. Board never accepts defrost completion signal
within the first 2 minutes in defrost cycle.
2. Defrost cycle time is limited to 20 minutes even
if defrost timer does not stop counting.
15
4. Controls and Adjustments
The dip switch is factory-adjusted to the following positions:
Dip Switch No. 1 2 3 4 5 6 7 8 9 10
KM-320MAH
KM-320MWH
OFF OFF OFF ON ON ON OFF OFF OFF OFF
OFF OFF OFF ON ON ON OFF OFF OFF OFF
Switch Nos. 1 and 2:
Used for adjustment of the defrost timer.
The defrost timer starts counting when the thermistor reads a certain temperature at
the evaporator outlet.
Switch Nos. 3 and 4:
Used for adjustment of the drain timer.
When a freeze cycle is completed, the pump motor stops, and the icemaker resumes
operation in 2 seconds. Then the pump motor drains the water tank for the time
determined by the drain timer. The drain timer also determines the time to restrain
completion of a defrost cycle, i.e. the minimum defrost time.
Switch Nos. 5 and 6:
Used for adjustment of the drain counter.
The pump motor drains the water tank at the frequency determined by the drain
counter.
Switch Nos. 7 and 8:
Used only for checking the controller board. Usually set in OFF position.
Switch Nos. 9 and 10:
Used for adjustment of freeze timer.
The freeze timer determines maximum
freeze cycle time. Upon termination of
freeze timer, machine initiates the
harvest cycle. After 2 consecutive timer
terminations, machine will shut down,
possibly indicating a problem.
16
a) Defrost Control
A thermistor (semiconductor) is used for a defrost control sensor. The resistance varies
depending on the suction line temperatures. The thermistor detects the temperature of
the evaporator outlet to start the defrost timer. No adjustment is required. If necessary,
check for resistance between thermistor leads, and visually check the thermistor
mounting, located on the suction line next to the evaporator outlet.
Temperature (°F) Temperature (°C)
0 -18 14.401
10 -12 10.613
32
50 10 3.871
70 21 2.474
90 32 1.633
Check a thermistor for resistance by using the following procedure:
1) Disconnect the connector K3 on the board.
2) Remove the thermistor. See "V.H. Removal and Replacement of Thermistor."
3) Immerse the thermistor sensor portion in a glass containing ice and water for 2 or 3
minutes.
4) Check for a resistance between thermistor leads. Normal reading is within 3.5 to 7 k
Replace the thermistor if it exceeds the normal reading.
b) Defrost Timer
No adjustment is required under normal use, as the defrost timer is adjusted to the
suitable position. However, if necessary when all the ice formed on the evaporator does
not fall into the bin in the harvest cycle, adjust the defrost timer to longer setting by
adjusting the dip switch (No. 1 & 2) on the controller board.
0 6.000
Resistance (kΩ)
Ω.
Dip Switch Setting Time
No. 1 No. 2
OFF OFF 60
ON OFF 90
OFF ON 120
ON ON 180
17
(seconds)
c) Drain Timer
The drain timer is factory-adjusted, and no adjustment is required.
Dip Switch Setting
No. 3 No. 4
OFF OFF 10 150
ON OFF 10 180
OFF ON 10 120
ON ON 20 180
T1: Time to drain the water tank
T2: Time to restrain defrost completion
d) Drain Counter
The drain counter is factory-adjusted to drain the water tank every 10 cycles, and no
adjustment is required. However, where water quality is bad and the icemaker needs a
pump drain more often, the drain counter 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
Time (seconds)
T1
Frequency
T2
OFF ON every 5 cycles
ON ON every 10 cycles
18
e) Freeze Timer
CAUTION
Adjust to proper specification, or the unit may not operate correctly.
The freeze timer is factory adjusted and no adjustment is required. The setting
determines the maximum allowed freeze time to prevent possible freeze-up issues.
Dip Switch Setting Time
No. 9 No. 10
OFF OFF 60
OFF ON 50
ON OFF 70
ON ON 60
.
f) Bin Control
(minutes)
CAUTION
When the ambient temperature is below 45°F (7°C), the bin control thermostat
operates to stop the icemaker even if the ice storage bin is empty. When the
thermostat is set in the prohibited range, the icemaker operates continuously
even if the ice storage bin is filled with ice. Setting in the prohibited range might
cause severe damage to the icemaker resulting in failure.
No adjustment is required under normal use, as the bin control is factory-adjusted.
Adjust it, if necessary, so that the icemaker stops automatically within 10 seconds after
ice contacts the bin control thermostat bulb.
5. Checking the Controller Board
a) Visually check the sequence with the icemaker operating.
b) Visually check the controller board by using the following procedure:
1) Adjust the defrost timer to minimum position.
Disconnect the thermistor from the controller board.
Connect a 1.5 to 3.5 kΩ resistor to connector K3 (pins #1 and #2), and energize the
unit.
After the 1 minute ± 5 second water supply cycle and the 2 minute ± 10 second defrost
cycle, the unit should start the freeze cycle.
2) After the above step 1), disconnect the float switch leads from the controller board
within the first 5 minutes of the freeze cycle. The unit should go into the defrost cycle
after the first 5 minutes ± 20 seconds of the freeze cycle.
19
3) Reconnect the float switch connector to the controller board. After the first 5 minutes
of the freeze cycle, disconnect the float switch leads from the controller board. At this
point, the unit should start the defrost cycle.
4) After step 3), de-energize the unit and confirm that the defrost timer is in the minimum
position. Disconnect the resistor from the controller board and energize the unit. After
the 1 minute water supply cycle, the defrost cycle starts. Re-connect a 1.5 to 3.5 kΩ
resistor to connector K3 (pins #1 and #2) after the first 2 minutes of the defrost cycle.
The unit should start the freeze cycle after 1 minute ± 5 seconds from the resistor
connection.
c) Check the controller board using the controller board’s test program.
The output test switch "S3" provides a relay sequence test. With power OFF,
place S3 ON and switch power to ICE. The correct lighting sequence should be
none, 2, 3, 4, 1, and 4, normal sequence every 5 seconds. S3 should remain in the
OFF position for normal operation.
20
III. Technical Information
A. Water Circuit and Refrigerant Circuit
1. KM-320MAH
21
2. KM-320MWH
22
B. Wiring Diagram
1. KM-320MAH, KM-320MWH
Note: Pressure Switch KM-320MAH
Cut-out 412 PSIG
+21
0
Cut-in 327 ± 21 PSIG
23
Note: Pressure Switch KM-320MWH
Cut-out 384 PSIG
+21
0
Cut-in 284 ± 21 PSIG
C. Timing Chart
*1 The icemaker does not complete a defrost cycle in the first 2 or 3 minutes. See "II.B.4.
Controls and Adjustments."
24
*1 The pump motor waits for 2 seconds before starting a drain cycle. See "II.B.4. Controls
and Adjustments."
*2 The icemaker does not complete a defrost cycle in the first 2 or 3 minutes. See "II.B.4.
Controls and Adjustments."
25
D. Performance Data
PERFORMANCE DATA NO. 05A013 ISSUED: 11/29/05
ITEM: HOSHIZAKI MODULAR CRESCENT CUBER
MODEL: KM-320MAH
70/21 325 147 311 141 287 130
80/27 315 143 293 133 265 120
90/32 311 141 278 126 251 114
lbs./day kg./da
y
100/38 304 138 272 123 226 103
70/21
80/27
90/32
watts 100/38
70/21 117 0.44
97 0.37 86 0.33
80/27 102 0.39 72 0.27 69 0.26
90/32 97 0.37 51 0.19 44 0.17
gal./day m3/day
100/38 75 0.28 50 0.19 38 0.14
70/21
80/27
90/32
min. 100/38
70/21
80/27
90/32
min. 100/38
70/21 216 15.2
235 16.5 255 17.9
80/27 230 16.2 259 18.2 277 19.5
90/32 235 16.5 280 19.7 299 21.0
PSIG kg/cm2G
100/38 237 16.7 285 20.0 317 22.3
70/21 52 3.7 53 3.7 54 3.8
80/27 53 3.7 54 3.8 54 3.8
90/32 53 3.7 55 3.9 56 3.9
PSIG kg/cm2G
100/38 53 3.7 55 3.9 56 3.9
2.1
TOTAL HEAT OF REJECTION FROM CONDENSER 7,400 BTU/h [AT 90ºF (32ºC) / WT 70ºF (21ºC)]
SUCTION PRESSURE
HARVEST CYCLE TIME
HEAD PRESSURE
4.2
3.4
4.6 2.3
38
31
32
37
777
792
810
820
35
38
41
45
765
765
784
800
802
750
761
765
29
APPROXIMATE ICE
PRODUCTION PER 24 HR.
APPROXIMATE ELECTRIC
CONSUMPTION
APPROXIMATE WATER
CONSUMPTION PER 24 HR.
FREEZING CYCLE TIME
WATER TEMP. (ºF/ºC)
AMBIENT TEMP.
(ºF/ºC)
50/10 70/21 90/32
31
31
34
2.5
5.5
3.6
4.6
3.5
2.5
4.8
1. KM-320MAH
Note: Pressure data is recorded at 5 minutes into freeze cycle. The data not in bold
should be used for reference only.
We reserve the right to make changes in specifications and design without prior notice.
26
2. KM-320MWH
PERFORMANCE DATA NO. 05A014 ISSUED: 11/29/05
ITEM: HOSHIZAKI MODULAR CRESCENT CUBER
MODEL: KM-320MWH
70/21 352 160 348 158 324 147
80/27 349 158 342 155 309 140
90/32 348 158 337 153 308 140
lbs./day kg./da
y
100/38 337 153 330 150 281 127
70/21
80/27
90/32
watts 100/38
70/21 430 1.63
476 1.80 682 2.58
80/27 465 1.76 535 2.03 822 3.11
90/32 476 1.80 585 2.21 842 3.19
gal./day m3/day
100/38 605 2.29 645 2.44 1078 4.08
70/21
80/27
90/32
min. 100/38
70/21
80/27
90/32
min. 100/38
70/21 263 18.5 263 18.5 265 18.6
80/27 263 18.5 263 18.5 265 18.7
90/32 263 18.5 263 18.5 265 18.6
PSIG kg/cm2G
100/38 264 18.6 263 18.5 267 18.8
70/21 53 3.7 54 3.8 55 3.9
80/27 54 3.8 56 3.9 56 3.9
90/32 54 3.8 57 4.0 58 4.0
PSIG kg/cm2G
100/38 54 3.8 57 4.0 58 4.1
TOTAL HEAT OF REJECTION FROM COMPRESSOR 1,000 BTU/h [AT 90ºF (32ºC) / WT 70ºF (21ºC)]
WATER FLOW FOR CONDENSER 45 gal./h [AT 100ºF (38ºC) / WT 90ºF (32ºC)]
PRESSURE DROP OF COOLING WATER LINE less than 10 PSIG
28
28
30
2.8
5.0
3.6
4.4
3.5
2.8
4.5
27
APPROXIMATE ICE
PRODUCTION PER 24 HR.
APPROXIMATE ELECTRIC
CONSUMPTION
APPROXIMATE WATER
CONSUMPTION PER 24 HR.
FREEZING CYCLE TIME
WATER TEMP. (ºF/ºC)
115-120/60/1
50/10 70/21 90/32
726
727
723
720
719
730
728
727
30
32
33
35
722
718
715
710
31
28
29
31
HARVEST CYCLE TIME
HEAD PRESSURE
4.0
3.4
4.4 2.6
2.4
TOTAL HEAT OF REJECTION FROM CONDENSER 5,700 BTU/h [AT 90ºF (32ºC) / WT 70ºF (21ºC)]
SUCTION PRESSURE
Note: Pressure data is recorded at 5 minutes into freeze cycle. The data not in bold
We reserve the right to make changes in specifications and design without prior notice.
should be used for reference only.
27
IV. Service Diagnosis
[1]
The icemaker will not
start.
a)
Power Supply
1.
OFF position.
1.
Move to ON position.
2.
Tighten.
3.
Bad contacts.
3.
Check for continuity and
replace.
4.
Voltage too high.
4.
Check and get
recommended voltage.
b)
Fuse (Inside fused
disconnect, if any)
1.
Blown.
1.
Check for short circuit and
replace.
c)
Control Switch
1.
OFF position.
1.
Move to ICE position.
2.
Bad contacts.
2.
Check for continuity and
replace.
d)
Bin Control Thermostat
1.
Tripped with bin filled
with ice.
1.
Remove ice.
2.
Ambient temperature
too cool.
2.
Increase ambient
temperature.
3.
Set too warm.
3.
See "II.B.4. Controls
and Adjustments, f) Bin
Control."
4.
Bulb out of position.
4.
Place in position.
5.
Bad contacts or leaks
in bulb.
5.
Check for continuity and
replace.
e)
High Pressure Control
1.
Bad contacts.
1.
Check for continuity and
replace.
f)
Transformer
1.
Thermal fuse blown or
coil winding opened.
1.
Replace.
g)
Wiring to Controller
Board
1.
Loose connections or
open.
1.
Check for continuity and
replace.
h)
Thermistor
1.
Leads short-circuit
or open and high
temperature safety
operates.
1.
See "II.B.4. Controls and
Adjustments, a) Defrost
Control."
i)
Hot Gas Solenoid Valve
1.
Continues to open in
freeze cycle and high
temperature safety
operates.
1.
Check for power off in
freeze cycle and replace.
A. No Ice Production
Problem Possible Cause Remedy
2. Loose connection.
28
Problem Possible Cause Remedy
j)
Water Supply Line
1.
Water supply off and
water supply cycle
does not finish.
1.
Check and get
recommended pressure.
Water continues to
[2]
be supplied, and the
icemaker will not
start.
[3] Compressor will
not start or stops
operating.
2. Condenser water
pressure too low
or off and pressure
control opens and
closes frequently to
finally operate high
temperature safety.
k) Water Solenoid 1. Mesh filter or orifice
gets clogged and
water supply cycle
does not finish.
Coil winding opened. 2. Replace.
2.
3. Wiring to water valve. 3. Check for loose
l) Controller Board 1. Defective. 1. See "II.B.5. Checking the
m)Interlock Switch
(Cleaning Valve)
a)Float Switch 1. Connector
b)Controller Board 1. Defective. 1. Replace.
c) Contactor 1. Open coil or contacts
a)Wash Switch 1. WASH position. 1. Move to ICE position.
b)High Pressure
Controller
1. OFF Position 1. Move to ON position.
2. Bad contacts. 2. Check for continuity and
disconnected.
Leads opened or
2.
defective switch.
3. Float does not move
freely.
worn.
Bad contacts. 2. Check and replace.
2.
1. Dirty air filter or
condenser.
Ambient or condenser
2.
water temperature too
warm.
3. Refrigerant
overcharged.
4. Condenser water
pressure too low or off.
(water-cooled model)
5. Fan not operating.
(except water-cooled
model)
6. Refrigerant line or
components plugged.
2. Check and get
recommended pressure.
1. Clean.
connection or open, and
replace.
Controller Board."
replace.
1. Place in position.
2. Check and replace.
3. Clean or replace.
1. Replace.
1. Clean.
2. Reduce temperature.
3. Recharge.
4. Check and get
recommended pressure.
5. See chart A.[6]
6. Clean and replace drier.
29
Problem Possible Cause Remedy
c) Overload Protector 1. Bad contacts. 1. Check for continuity and
replace.
2. Voltage too low. 2. Increase voltage.
3. Refrigerant
overcharged or
undercharged.
4. Line valve continues
to close in freeze cycle
and overload protector
operates.
d)Starter 1. Bad contacts. 1. Check and replace.
Coil winding opened. 2. Replace.
2.
e)Start Capacitor or Run
Capacitor
f) Magnetic Contactor 1. Bad contacts. 1. Check for continuity and
g)Compressor 1. Wiring to compressor. 1. Check for loose
h)Controller Board 1. Defective. 1. See "II.B.5. Checking the
i) Water Regulator 1. Set too high. 1. Adjust lower.
1. Defective. 1. Replace.
Coil winding opened. 2. Replace.
2.
Defective. 2. Replace.
2.
3. Protector tripped. 3. Reduce temperature.
3. Recharge.
4. Check line valve’s
operation in freeze cycle
and replace.
replace.
connection or open, and
replace.
Controller Board."
[4] Water continues to
be supplied in freeze
cycle.
[5] No water comes from
spray tubes. Water
pump will not start, or
freeze cycle time is
too short.
a)Water Solenoid Valve 1. Diaphragm does not
close.
b)Controller Board 1. Defective. 1. See "II.B.5. Checking the
a)Water Supply Line 1. Water pressure too
low and water level in
water tank too low.
b)Water Solenoid Valve 1. Dirty mesh filter or
orifice and water level
in water tank too low.
c) Water System 1. Water leaks. 1. Check connections for
Clogged. 2. Clean.
2.
3. Pump out check valve
leaking by.
1. Check for water leaks with
icemaker off.
Controller Board."
1. Check and get
recommended pressure.
1. Clean.
water leaks, and replace.
3. Check assembly and
clean.
30
Problem Possible Cause Remedy
d)Pump Motor 1. Motor winding opened. 1. Replace.
Bearing worn out. 2. Replace.
2.
3. Wiring to pump motor. 3. Check for loose
connection or open, and
replace.
4. Defective capacitor. 4. Replace.
[6] Fan motor will
not start, or is not
operating.
[7] All components
run, but no ice is
produced.
5. Defective or bound
impeller.
6. Mechanical seal worn
out.
e)Controller Board 1. Defective. 1. See "II.B.5. Checking the
a)Fan Motor 1. Motor winding opened. 1. Replace.
Bearing worn out. 2. Replace.
2.
3. Wiring to fan motor. 3. Check for loose
4. Defective capacitor. 4. Replace.
5. Fan blade bound. 5. Check and replace.
b)Controller Board 1. Defective. 1. See "II.B.5. Checking the
a)Refrigerant 1. Undercharged. 1. Check for leaks and
Air or moisture
2.
trapped.
b)Compressor 1. Defective valve. 1. Replace.
c) Hot Gas Solenoid Valve 1. Continues to open in
freeze cycle.
d)Line Valve 1. Continues to close in
freeze cycle.
e)Water Supply Line
(water-cooled model)
f) Water Solenoid Valve 1. Water solenoid valve
1. Condenser water
pressure too low or off
and pressure control
opens and closes
frequently.
is wide open during
freeze.
5. Replace and clean.
6. Check and replace.
Controller Board."
connection or open, and
replace.
Controller Board."
recharge.
2. Replace drier and
recharge.
1. Check and replace.
1. Check and replace.
1. Check and get
recommended pressure.
1. Check for water leaks with
icemaker off.
B. Evaporator is Frozen Up
Problem Possible Cause Remedy
[1]Freeze cycle time is
too long.
a)Float Switch 1. Leads short-circuit or
defective switch.
2. Float does not move
freely.
b)Water Solenoid Valve 1. Diaphragm does not
close.
31
1. Check and replace.
2. Clean or replace.
1. Check for water leaks with
icemaker off.
Problem Possible Cause Remedy
c) Controller Board 1. Defective. 1. See "II.B.5. Checking the
Controller Board."
[2]All ice formed on
evaporator does not
fall into bin in harvest
cycle.
a)Evaporator 1. Scaled up. 1. Clean.
b)Water Supply Line 1. Water pressure too
low.
c) Water Filter System 1. Dirty/Restricted 1. Replace filter.
d)Water Solenoid Valve 1. Dirty mesh filter or
orifice.
2. Diaphragm does not
close.
e) Ambient and/or water
temperature.
f) Line Valve 1. Continues to open in
1. Too cool. 1. Increase temperature.
harvest cycle.
1. Check and get
recommended pressure.
1. Clean.
2. Check for water leaks with
icemaker off.
1. Check operation in harvest
cycle and replace.
g)Thermistor 1. Out of position or
loose attachment.
h)Controller Board 1. Defrost timer is set
too short.
Defective. 2. See "II.B.5. Checking the
2.
[3]Other a)Spray Tubes 1. Clogged. 1. Clean
Out of position. 2. Place in position.
2.
b)Water System 1. Dirty. 1. Clean.
c) Refrigerant 1. Undercharged. 1. Check for leaks and
d)Expansion Valve 1. Bulb out of position or
loose attachment.
2. Defective. 2. Replace.
e)Hot Gas Solenoid Valve 1. Coil winding opened. 1. Replace.
Plunger does not
2.
move.
3. Wiring to hot gas
valve.
f) Water Supply Line 1. Too small; requires
3/8" OD line dedicated
per machine.
1. See "V.H. Removal
and Replacement of
Thermistor."
1. Adjust longer, referring
to "II.B.4. Controls and
Adjustments, b) Defrost
Timer.
Controller Board."
recharge.
1. Place in position.
2. Replace.
3. Check for loose
connection or open, and
replace.
1. Increase water line size.
g)Water Filter (if installed) 1. Flow rate too small. 1. Replace with filter that has
larger flow rate.
32
C. Low Ice Production
Problem Possible Cause Remedy
[1] Freeze cycle time is
long.
[2] Harvest cycle time is
long.
a) See chart A.[3] and check dirty air filter or condenser, ambient or water
temperature, water pressure, water regulator, and refrigerant charge.
b) See chart B.[1] and check float switch, water solenoid valve and controller
board.
a) See chart B.[2] and check controller board, thermistor, evaporator, ambient
and/or water temperature, water supply line, water solenoid valve, line valve,
and gas valve.
D. Abnormal Ice
Problem Possible Cause Remedy
[1] Small cubes. a) Ice Cube Guide 1. Out of position.
Circulated water falls
into bin.
b) See chart A.[5] and check water supply line, water solenoid valve, water
system, pump motor, and controller board.
c) Drain Valve 1. Dirty. 1. Clean.
1. Place in position.
Cloudy or irregular
[2]
cubes.
a) See chart B.[1] and B.[3], and check float switch, water solenoid valve,
controller board, spray tubes, water system, refrigerant charge, and expansion
valve.
b) Spray Guide 1. Dirty. 1. Clean.
c) Water Quality 1. High hardness or
contains impurities.
1. Install a water softener or
filter.
E. Other
Problem Possible Cause Remedy
[1] Icemaker will not stop
when bin is filled with
ice.
[2] Abnormal noise. a) Pump Motor 1. Bearings worn out. 1. Replace
[3] Ice in storage bin
often melts.
a) Bin Control Thermostat 1. Set too cold. 1. Adjust warmer.
2. Defective. 2. Replace
b) Fan Motor 1. Bearings worn out. 1. Replace
2. Fan blade deformed. 2. Replace fan blade.
3. Fan blade does not
move freely.
c) Compressor 1. Bearings worn out or
cylinder valve broken.
2. Mounting pad out of
position.
d) Refrigerant Lines 1. Rub or touch other
lines or surfaces.
a) Bin Drain 1. Plugged. 1. Clean.
b) Icemaker and Bin 1. Drains not run
separately.
3. Replace.
1. Replace.
2. Reinstall.
1. Replace.
1. Separate the drain lines.
33
V. Removal and Replacement of Components
IMPORTANT
Ensure all components, fasteners and thumbscrews are securely in place after
the equipment is serviced.
IMPORTANT
1. The Polyol Ester (POE) oils used in R-404A units can absorb moisture
quickly. Therefore it is important to prevent moisture from entering the system
when replacing or servicing parts.
2. Always install a new drier every time the sealed refrigeration system is
opened.
3. Do not leave the system open for longer than 5 minutes when replacing or
servicing parts.
A. Service for Refrigerant Lines
1. Refrigerant Recovery
The icemaker unit is provided with two refrigerant access valves–one on the low-side
and one on the high-side line. Using proper refrigerant practices recover the refrigerant
from the access valves and store it in an approved container. Do not discharge the
refrigerant into the atmosphere.
2. Evacuation and Recharge (R-404A)
1) Attach charging hoses, a service manifold and a vacuum pump to the system. Be sure
to connect charging hoses to both high and low-side access valves.
IMPORTANT
The vacuum level and vacuum pump may be the same as those for current
refrigerants. However, the rubber hose and gauge manifold to be used for
evacuation and refrigerant charge should be exclusively for POE oils.
2) Turn on the vacuum pump. Never allow the oil in the vacuum pump to flow backward.
3) Allow the vacuum pump to pull down to a 29.9" Hg vacuum. Evacuating period depends
on pump capacity.
4) Close the low-side valve and high-side valve on the service manifold.
5) Disconnect the vacuum pump and attach a refrigerant service cylinder to the highside line. Remember to loosen the connection and purge the air from the hose. See
the nameplate for the required refrigerant charge. Hoshizaki recommends only virgin
refrigerant or reclaimed refrigerant which meets ARI Standard No. 700-88 be used.
6) A liquid charge is recommended for charging an R-404A system. Invert the service
cylinder. Open the high-side, service manifold valve.
7) Allow the system to charge with liquid until the pressures balance.
34
8) If necessary, add any remaining charge to the system through the low-side. Use a
throttling valve or liquid dispensing device to add the remaining liquid charge through
the low-side access port with the unit running.
9) Close the two refrigerant access valves and disconnect the hoses and service manifold.
10) Cap the access valves to prevent a possible leak.
B. Brazing
DANGER
1. Refrigerant R-404A itself is not flammable at atmospheric pressure and
temperatures up to 176° F.
2. Refrigerant R-404A itself is not explosive or poisonous. However, when
exposed to high temperatures (open flames) R-404A can be decomposed to
form hydrofluoric acid and carbonyl fluoride both of which are hazardous.
3. Always recover the refrigerant and store it in an approved container. Do not
discharge the refrigerant into the atmosphere.
4. Do not use silver alloy or copper alloy containing arsenic.
5. Do not use R-404A as a mixture with pressurized air for leak testing.
Refrigerant leaks can be detected by charging the unit with a little refrigerant,
raising the pressure with nitrogen and using an electronic leak detector.
Note: All brazing-connections inside the evaporator case are clear-paint coated.
Sandpaper the brazing connections before unbrazing the components. Use a
good abrasive cloth to remove coating.
35
C. Removal and Replacement of Compressor
IMPORTANT
Always install a new drier every time the sealed refrigeration system is opened.
Do not replace the drier until after all other repair or replacement has been
made.
Note: When replacing a compressor with a defective winding, be sure to install the
new start capacitor and start relay supplied with the replacement compressor.
Due to the ability of the POE oil in the compressor to absorb moisture quickly,
the compressor must not be opened more than 15 minutes for replacement or
service. Do not mix lubricants of different compressors even if both are charged
with R-404A, except when they use the same lubricant.
1) Turn off the power supply.
2) Remove the panels.
3) Recover the refrigerant and store it in an approved container.
4) Remove the terminal cover on the compressor and disconnect the compressor wiring.
5) Remove the discharge and suction pipes using brazing equipment.
6) Remove the hold-down bolts, washers and rubber grommets.
7) Slide and remove the compressor. Unpack the new compressor package. Install the
new compressor.
8) Attach the rubber grommets of the prior compressor.
9) Sandpaper the suction, discharge and process pipes.
10) Place the compressor in position and secure it using the bolts and washers.
11) Remove plugs from the suction, discharge and process pipes.
12) Braze the process, suction and discharge lines (do not change this order), while
purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG.
13) Install a new drier.
14) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.
15) Evacuate the system and charge it with refrigerant. See the nameplate for the required
refrigerant charge.
16) Connect the terminals and replace the terminal cover in its correct position.
17) Replace the panels in their correct positions.
18) Turn on the power supply.
36
D. Removal and Replacement of Drier
IMPORTANT
Always install a new drier every time the sealed refrigeration system is opened.
Do not replace the drier until after all other repair or replacement has been
made.
1) Turn off the power supply.
2) Remove the panels.
3) Recover the refrigerant and store it in an approved container.
4) Remove the drier.
5) Install the new drier with the arrow on the drier in the direction of the refrigerant flow.
Use nitrogen gas at a pressure of 3 to 4 PSIG when brazing the tubings.
6) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.
7) Evacuate the system, and charge it with refrigerant. See the nameplate for the required
refrigerant charge.
8) Replace the panels in their correct positions.
9) Turn on the power supply.
E. Removal and Replacement of Expansion Valve
IMPORTANT
Sometimes moisture in the refrigerant circuit exceeds the drier capacity and
freezes up at the expansion valve. Always install a new drier every time the
sealed refrigeration system is opened. Do not replace the drier until after all
other repair or replacement has been made.
1) Turn off the power supply.
2) Remove the panels.
3) Recover the refrigerant and store it in an approved container.
4) Remove the insulation and the expansion valve bulb on the suction line.
5) Remove the expansion valve cover and disconnect the expansion valve using brazing
equipment.
37
6) Braze the new expansion valve, with nitrogen gas flowing at a pressure of 3 to 4 PSIG.
WARNING
1. Do not heat the wall. Place a steel barrier for protection.
2. Always protect the valve body by using a damp cloth to prevent the valve
from overheating. Do not braze with the valve body exceeding 250°F
(121°C).
7) Install a new drier.
8) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.
9) Evacuate the system and charge it with refrigerant. See the nameplate for the required
refrigerant charge.
10) Attach the bulb to the suction line in position. Be sure to secure it with clamps and to
insulate it.
11) Place the new set of expansion valve covers in position.
12) Replace the panels in their correct positions.
13) Turn on the power supply.
F. Removal and Replacement of Hot Gas Valve and Line Valve
CAUTION
Always use a copper tube of the same diameter and length when replacing the
hot gas lines; otherwise the performance may be reduced.
IMPORTANT
Always install a new drier every time the sealed refrigeration system is opened.
Do not replace the drier until after all other repair or replacement has been
made.
1) Turn off the power supply.
2) Remove the panels.
3) Recover the refrigerant and store it in an approved container.
4) Remove the screw and the solenoid.
5) Disconnect the hot gas valve or line valve using brazing equipment.
6) Install the new valve.
WARNING
Always protect the valve body by using a damp cloth to prevent the valve from
overheating. Do not braze with the valve body exceeding 250°F (121°C).
38
7) Install a new drier.
8) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.
9) Evacuate the system and charge it with refrigerant. See the nameplate for the required
refrigerant charge.
10) Cut the leads of the solenoid allowing enough lead length to reconnect using closed
end connectors.
11) Connect the new solenoid leads.
12) Attach the solenoid to the valve body and secure it with a screw.
13) Replace the panels in their correct positions.
14) Turn on the power supply.
G. Removal and Replacement of Evaporator
IMPORTANT
Always install a new drier every time the sealed refrigeration system is opened.
Do not replace the drier until after all other repairs or replacement have been
made.
1) Turn off the power supply.
2) Remove the panels and the top insulation over the evaporator.
3) Recover the refrigerant and store it in an approved container.
4) Remove the spray tubes and the insulations at the "U" shaped notch where the
refrigeration tubings pass through the molded chassis.
5) Remove the insulation tube and disconnect the evaporator inlet tubing at the tee next to
the expansion valve.
6) Lift up the evaporator and disconnect the evaporator outlet tubing.
7) Install the new evaporator.
8) Install the new drier.
9) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.
10) Evacuate the system and charge it with refrigerant. See the nameplate for the required
refrigerant charge.
11) Replace the removed parts in the reverse order of which they were removed.
12) Replace the top insulation and the panels in their correct positions.
13) Turn on the power supply.
39
H. Removal and Replacement of Thermistor
CAUTION
1. Fragile, handle very carefully.
2. Always use a recommended sealant (High Thermal Conductive Type), Model
KE4560RTV manufactured by SHINETSU SILICONE, Part Code 60Y000-11,
or Part Code 4A0683-01 equivalent.
3. Always use a recommended foam insulation (Non-absorbent Type) or
equivalent.
4. Do not shorten or cut the thermistor leads when installing it.
1) Turn off the power supply.
2) Remove the panels.
3) Remove the control box cover.
4) Disconnect the thermistor leads from the
K3 connector on the controller board.
5) Remove the plastic cable ties, foam
insulation, thermistor holder and thermistor.
See Fig. 1.
6) Scrape away the old sealant on the
thermistor holder and the suction pipe.
Thermistor Lead Cable Tie
Foam Insulation Thermistor Holder
Fig. 1
7) Wipe off moisture or condensation on the
suction pipe.
8) Smoothly apply recommended sealant (KE4560RTV, Part Code 60Y000-11 or
4A0683-01) to the thermistor holder concave.
9) Attach the new thermistor to the suction pipe very carefully to prevent damage to the
leads. And secure it using the thermistor holder and recommended foam insulation.
10) Secure the insulation using the plastic cable ties.
11) Connect the thermistor leads through the bushing of the control box to the K3 connector
on the controller board.
Note: Do not cut the leads of the thermistor while installing it.
12) Replace the control box cover and the panels in their correct positions.
13) Turn on the power supply.
40
I. Removal and Replacement of Fan Motor
Note: When replacing a fan motor with defective winding, it is recommended that a new
capacitor be installed.
1) Turn off the power supply.
2) Remove the panels.
3) Remove the closed end connectors from the fan motor leads.
4) Remove the fan motor bracket and fan motor.
5) Install the new fan motor and replace the removed parts in the reverse order of which
they were removed.
6) Replace the panels in their correct positions.
7) Turn on the power supply.
J. Removal and Replacement of Water Valve
1) Turn off the power supply.
2) Close the water supply line shut-off valve.
3) Remove the front panel.
4) Remove the valve outlet tubing by releasing the clamp.
5) Remove the bracket from the unit.
6) Remove the fitting nut and water valve.
7) Disconnect the terminals from the water valve.
8) Install the new water valve and replace the removed parts in the reverse order of which
they were removed.
9) Open the water supply line shut-off valve.
10) Turn on the power supply.
11) Check for leaks.
12) Replace the front panel in its correct position.
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K. Removal and Replacement of Pump Motor
1) Turn off the power supply.
2) Remove the front panel.
3) Remove the base cover.
4) Drain the water tank by removing one end of the pump tubing.
5) Replace the removed parts in their correct positions.
6) Disconnect the pump suction and discharge hoses.
7) Remove the closed end connectors from the pump motor leads.
8) Remove the screw attaching the pump motor assembly to the base, then remove the
pump motor assembly.
9) Remove the screw attaching the pump motor to the pump motor bracket.
10) Remove the screws attaching the pump housing to the pump motor. Remove the
housing and check the impeller.
11) If the impeller is defective, install a new impeller.
12) Install the new motor or new parts, and replace the removed parts in the reverse order
of which they were removed.
13) Turn on the power supply and check for leaks.
14) Replace the base cover in its correct position.
15) Replace the front panel in its correct position.
L. Removal and Replacement of Spray Tubes
1) Turn off the power supply.
2) Remove the front panel and the insulation panel.
3) Remove the rubber hoses from the spray tubes (water supply pipe).
4) Release the clamps and disconnect the rubber hoses.
5) Remove the spray tubes by squeezing the side tabs.
6) Install the new spray tubes, and replace the removed parts in the reverse order of
which they were removed.
7) Replace the panels in their correct positions.
8) Turn on the power supply.
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M. Removal and Replacement of Water Regulating Valve –
Water-Cooled Model Only
IMPORTANT
Always install a new drier every time the sealed refrigeration system is opened.
Do not replace the drier until after all other repair or replacement has been
made.
1) Turn off the power supply.
2) Close the water supply line shut-off valve.
3) Remove the panels.
4) Recover the refrigerant and store it in an approved container.
5) Disconnect the capillary tube at the condenser outlet using brazing equipment.
6) Disconnect the flare-connections of the valve.
7) Remove the screws and the valve from the bracket.
8) Install the new valve, and braze the capillary tube.
9) Install a new drier.
10) Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.
11) Evacuate the system, and charge it with refrigerant. See the nameplate for the required
refrigerant charge.
12) Connect the flare-connections.
13) Open the water supply line shut-off valve.
14) Check for water leaks.
15) Replace the panels in their correct positions.
16) Turn on the power supply.
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N. Adjustment Of Water Regulating Valve – Water-Cooled Model Only
The water regulating valve (also called "water regulator") is factory-adjusted. No
adjustment is required under normal use. Adjust the water regulator, if necessary, using
the following procedure.
1) Attach a pressure gauge to the high-side line of the system. Or prepare a thermometer
to check for the condenser drain temperature.
2) Rotate the adjustment screw by using a flat blade screwdriver, so that the pressure
gauge shows 270 PSIG or the thermometer reads 104 to 115°F, 5 minutes after a
freeze cycle or icemaking process starts. When the pressure exceeds 270 PSIG,
or the condenser drain temperature exceeds 115°F, rotate the adjustment screw
counterclockwise. See Fig. 2.
3) Check that the pressure or the condenser drain temperature holds a stable setting.
Adjustment Screw
CW – Higher
CCW – Lower
Top View
Adjustment Screw
Fig. 2
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VI. Cleaning and Maintenance Instructions
IMPORTANT
Ensure all components, fasteners and thumbscrews are securely in place after
any maintenance or cleaning is done to the equipment.
A. Preparing the Icemaker for Long Storage
WARNING
When shutting off the icemaker for an extended time, drain out all water from
the water tank and remove the ice from the storage bin. The storage bin should
be cleaned and dried. Drain the icemaker to prevent damage to the water
supply line at sub-freezing temperatures, using air or carbon dioxide. Shut off
the icemaker until the proper ambient temperature is resumed.
When the icemaker is not used for two or three days, it is sufficient to only move the control
switch to the "OFF" position, unless the icemaker will be at sub-freezing temperatures.
1. On water-cooled model only, first remove the water from the water-cooled condenser:
1) Remove the front panel.
2) Move the control switch on the control box to the "OFF" position.
3) Wait 3 minutes.
4) Move the control switch to the "ICE" position.
5) Allow 5 minutes for the icemaker to fill with water and the water pump to start operating.
6) Close the water-cooled condenser water supply line shut-off valve.
7) Open the drain valve for the water-cooled condenser water supply line.
8) Allow the line to drain by gravity.
9) Attach compressed air or carbon dioxide supply to the condenser water line drain valve.
10) Quickly blow the water-cooled condenser out, using compressed air or carbon dioxide
until water stops coming out.
2. Remove the water from the potable water supply line:
1) Remove the front panel (except water-cooled model).
2) Move the control switch on the control box to the "OFF" position.
3) Wait 3 minutes.
4) Close the potable water supply line shut-off valve and open the potable water supply
line drain valve.
5) Allow the line to drain by gravity.
6) Attach compressed air or carbon dioxide supply to the potable water line drain valve.
7) Move the control switch to the "ICE" position.
8) Blow the potable water line out using compressed air or carbon dioxide.
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3. Drain the potable water tank:
1) Turn off the power supply.
2) Move the control switch to the "OFF" position.
3) Drain the water tank by removing the base
cover and one end of the pump tubing. See
Fig. 4.
4) Replace the removed parts in their correct positions.
5) Remove all ice from the storage bin, and
clean the storage bin.
6) Replace the front panel in its correct position.
7) Close the drain valve.
Fig. 4
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B. Cleaning and Sanitizing Instructions
IMPORTANT
Ensure all components, fasteners and thumbscrews are securely in place after
any maintenance or cleaning is done to the equipment.
WARNING
1. HOSHIZAKI recommends cleaning this unit at least once a year. More
frequent cleaning, however, may be required in some existing water
conditions.
2. To prevent injury to individuals and damage to the icemaker, do not use
ammonia type cleaners.
3. Always wear liquid-proof gloves to prevent the cleaning and sanitizing
solutions from coming into contact with skin.
IMPORTANT
1. The cleaning valve is used to allow solution flow to the inside of the
evaporator during the cleaning and sanitizing operation. It should be closed
for all icemaking operation. The compressor will not operate unless this valve
is completely closed.
2. To open the cleaning valve, the valve handle should be parallel to the valve
body. To close the valve, the valve handle should be at a right angle to the
valve body.
Closed Position
Open Position
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1. Cleaning Procedure
1) Dilute approximately 16 fl. oz. of the recommended cleaner Hoshizaki "Scale Away" or
"LIME-A-WAY" (Economics Laboratory, Inc.) with 3 gal. of water.
2) Remove all ice from the evaporator and the storage bin.
Note: To remove cubes on the evaporator, turn off the power supply and turn it on
after 3 minutes. The defrost cycle starts and the cubes will be removed from the
evaporator.
3) Turn off the power supply.
4) Remove the front panel and the base cover, and then remove the insulation panel by
lifting up the panel slightly and pulling it towards you.
5) Remove one end of the pump tubing (see Fig. 4). Drain the water tank. Replace the
pump tubing in its correct position.
6) In bad or severe water conditions, clean the float switch assembly as described below.
Otherwise, continue to step 7.
a. Remove the float switch assembly from the mounting bracket and remove the rubber
boot from the bottom of the assembly.
b. Remove the retainer rod from the bottom of the float switch assembly, then remove
the float. Be careful not to bend the retainer rod excessively when removing it.
c. Wipe down the float switch assembly's housing, shaft, float, and retainer rod with
cleaning solution. Wipe the inside of the rubber boot with cleaning solution.
d. Reassemble the float switch assembly and replace it and the rubber boot in their
correct positions.
7) Pour the cleaning solution into the water tank.
8) Fully open the cleaning valve on the left side wall of the machine compartment.
9) Move the control switch on the control box to the "WASH" position.
10) Replace the insulation panel and the front panel in their correct positions.
11) Turn on the power supply, and start the washing process.
12) Turn off the power supply after 30 minutes.
13) Remove the front panel.
14) Remove one end of the pump tubing. Drain the water tank. Replace the pump tubing in
its correct position.
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15) Move the control switch to the "ICE" position.
16) Close the cleaning valve.
Note: The icemaker will not operate unless the cleaning valve is completely closed.
17) Replace the front panel in its correct position.
18) Turn on the power supply to fill the water tank with water.
19) Turn off the power supply after 3 minutes.
20) Remove the front panel, and fully open the cleaning valve.
21) Move the control switch to the "WASH" position.
22) Replace the front panel in its correct position.
23) Turn on the power supply to rinse off the cleaning solution.
24) Turn off the power supply after 5 minutes.
25) Remove the front panel.
26) Remove one end of the pump tubing. Drain the water tank. Replace the pump tubing in
its correct position.
27) Repeat steps 15 through 26 three more times to rinse thoroughly.
Note: If you do not sanitize the icemaker, go to step 10 in "2. Sanitizing Procedure."
2. Sanitizing Procedure - Following Cleaning Procedure
1) Dilute a 5.25 % sodium hypochlorite solution (chlorine bleach) with water (add 1.5 fl. oz.
of sanitizer to 3 gal. of water).
2) Remove the insulation panel.
3) Pour the sanitizing solution into the water tank.
4) Replace the insulation panel and the front panel in their correct positions.
Note: Make sure that the control switch is in the "WASH" position and the cleaning
valve is open.
5) Turn on the power supply, and start the sanitizing process.
6) Turn off the power supply after 15 minutes.
7) Remove the front panel.
8) Remove one end of the pump tubing. Drain the water tank. Replace the pump tubing in
its correct position.
9) Repeat steps 15 through 26 in "1. Cleaning Procedure" two times to rinse thoroughly.
10) Close the cleaning valve.
11) Move the control switch to the "ICE" position.
12) Replace the front panel and the base cover in their correct positions.
13) Clean the storage bin with water.
14) Turn on the power supply, and start the automatic icemaking process.
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C. Maintenance
IMPORTANT
This icemaker must be maintained individually, referring to the instruction
manual and labels provided with the icemaker.
1) Stainless Steel Exterior
To prevent corrosion, wipe the exterior occasionally with a clean and soft cloth. Use a
damp cloth containing a neutral cleaner to wipe off oil or dirt build up.
2) Storage Bin and Scoop
• Wash your hands before removing ice. Use the plastic scoop provided.
• The storage bin is for ice use only. Do not store anything else in the bin.
• Keep the scoop clean. Clean it by using a neutral cleaner and rinse thoroughly.
• Clean the bin liner by using a neutral cleaner. Rinse thoroughly after cleaning.
3) Condenser (except water-cooled model)
Check the condenser once a year, and clean the coil if required by using a brush or
vacuum cleaner. More frequent cleaning may be required depending on the location of
the icemaker.
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