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Hoshizaki America, Inc.
Hoshizaki
Modular Crescent Cuber
Models
KM-320MAH
KM-320MWH
SERVICE MANUAL
“A Superior Degree
of Reliability”
www.hoshizaki.com
Number: 73132
Issued: 1-24-2006
Revised: 11-30-2006
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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 D
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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-30MAH (air-cooled) ..............................
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K. Removal and Replacement of Pump Motor ................................................................ 4 L. Removal and Replacement of Spray Tubes ................................................................. 4 M. Removal and Replacement of Water Regulating Valve – Water-Cooled Model Only . 43 N. Adjustment Of Water Regulating Valve – Water-Cooled Model Only .......................... 44 VI. Cleaning and Maintenance Instructions ..........................................................
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I. Specifications SPECIFICATION NO. 05A013 ISSUED: 11/29/2005 ITEM: HOSHIZAKI MODULAR CRESCENT CUBER A. KM-320MAH (air-cooled) 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) *2
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B. KM-320MWH (water-cooled) 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)
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II. General Information A. Construction 1. KM-320MAH (air-cooled) Spray Tubes Expansion Valve Control Switch Water Supply Inlet Evaporator Hot Gas Valve Cleaning Valve Condenser Bin Control Thermostat Fan Motor Float Switch Water Pump Drier Compressor Control Box (shown transparent to allow view of other components) 7
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2. KM-320MWH (water-cooled) Spray Tubes Expansion Valve Control Switch Water Supply Inlet Hot Gas Valve Evaporator Water Regulator Cleaning Valve Condenser Bin Control Thermostat Float Switch Water Pump Drier Compressor Control Box (shown transparent to allow view of other components) 8
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B. Controller Board 1. Solid-State Control • A HOSHIZAKI exclusive solid-state control is employed in KM-30MAH and KM-30MWH 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. . A controller board contains integrated circuits, which are susceptible to failure due to static discharge. It is esp
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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 17 ± 7°F (53 ± 4°C) the thermistor
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The green LEDs 1-4 represent the corresponding relays and energize and sequence 5 seconds from initial startup as follows: Time LEDs are Lit Sequence Step LED Min. Max. Avg. 1 Minute Fill Cycle 4 60 seconds Harvest Cycle 1, 4, and minutes 0 minutes 3 to 5 minutes Freeze Cycle 1 5 minutes 60 minutes 30 to 35 minutes Reverse Pump Out 1, 3, and 10 seconds 0 seconds factory setting {LED 1 – Comp; LED - HGV/CFM; L ED 3 – PM; LED 4 - WV} The built in safeties shut down the unit and
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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
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3. Sequence 1st Cycle 1. Unit energized and control switch to "ICE" 3. Thermistor reads 48°F (9°C). position. Water supply cycle starts. Defrost timer starts counting. . After 1 minute, defrost cycle starts. Water Valve Water Valve Hot Gas Valve Defrost Cycle Freeze Cycle Pump, Fan & Line Valve IMPORTANT Water valve opening is limited to 6 minutes. 5. After the first 5 minutes in freeze cycle. 4. Defrost timer stops counting. Ready to complete freeze cycle when float Defrost cycle is
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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. . Drain timer stops counting. Pump drain is completed. 1. Float switch opens and signals to complete freeze cycle. Drain timer starts counting. Drain Pump Hot Gas Valve Defrost Cycle 3. Thermistor reads 48°F (9°C). Defrost timer starts counting. Freeze Cycle IMPORTANT Pump, Fan & Water valve opening is limited to 6 minutes. Line Valve 5
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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 . Thermistor reads 48°F (9°C). freeze cycle. Defrost timer starts counting. Water Valve Hot Gas Valve Defrost Cycle Freeze Cycle Pump, Fan & IMPORTANT Water valve opening is Line Valve limited to 6 minutes. 4. After the first 5 minutes in freeze cycle. 3. Defrost timer stops counting. Rea
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4. Controls and Adjustments The dip switch is factory-adjusted to the following positions: Dip Switch No. 1 3 4 5 6 7 8 9 10 KM-30MAH OFF OFF OFF ON ON ON OFF OFF OFF OFF KM-30MWH OFF OFF OFF ON ON ON OFF OFF OFF OFF Switch Nos. 1 and : 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 m
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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) Resistance (k Ω) 0 -18 14.4
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c) Drain Timer The drain timer is factory-adjusted, and no adjustment is required. Time (seconds) Dip Switch Setting T1 No. 3 No. 4 T OFF OFF 10 150 ON OFF 10 180 OFF ON 10 10 ON ON 0 180 T1: Time to drain the water tank T: 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 count
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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 (minutes) No. 9 No. 10 OFF OFF 60 OFF ON 50 ON OFF 70 ON ON 60 . f) Bin Control CAUTION When the ambient temperature is below 45°F (7°C), the bin control thermostat operates to stop the icemaker even if the ice storag
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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 k