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Reliability is a beautiful thing MODULAR CRESCENT CUBER KM-500MAH KM-500MWH KM-500MRH SERVICE MANUAL NUMBER: 73104 ISSUED: NOV. 7, 2002 ™ REVISED: DEC. 16, 2003...
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No 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.
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IV. SERVICE DIAGNOSIS................... 41 1. NO ICE PRODUCTION ..................41 2. EVAPORATOR IS FROZEN UP ................42 3. LOW ICE PRODUCTION ..................42 4. ABNORMAL ICE ....................45 5. OTHERS ......................45 V. REMOVAL AND REPLACEMENT OF COMPONENTS ..........46 1.
SPECIFICATIONS KM-500MAH AC SUPPLY VOLTAGE 115/60/1 AMPERAGE 13 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) lbs./day ( kg/day )
KM-500MWH Serial #L00001D - M20960C AC SUPPLY VOLTAGE 115/60/1 AMPERAGE 10 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) lbs./day ( kg/day ) *463 (210)
KM-500MWH Serial #M30961D - AC SUPPLY VOLTAGE 115/60/1 AMPERAGE 10 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) lbs./day ( kg/day ) *480 (218)
KM-500MRH AC SUPPLY VOLTAGE 115/60/1 AMPERAGE 15 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) lbs./day ( kg/day ) *517 235) 493 (224) 449 (204)
4. CONDENSER UNIT URC-6F 24" (610 mm.) 23-1/32" (585 mm.) 19-11/16" 6/16" x 3/4" (10 mm. x 20 mm.) (500 mm.) 4 x 2 (SLOTTED HOLES) 18-1/8" (460 mm.) 20-15/32" (520 mm.) 21-15/16" (557 mm.) 7/8" DIA. HOLE (23 mm. DIA.) 6-5/16"...
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SPECIFICATIONS MODEL: URC-6F EXTERIOR Galvanized Steel DIMENSIONS (W x D x H) 21-15/16" x 15-11/16" x 17-7/8" (557 x 398 x 453.8 mm.) REFRIGERANT CHARGE R404A 1 lb. 2 oz. (505 g) WEIGHT Net 61 lbs. (28 kg) Shipping 68 lbs. (31 kg) CONNECTIONS REFRIGERANT One Shot Couplings (Aeroquip)
GENERAL INFORMATION 1. CONSTRUCTION [a] KM-500MAH Spray Tubes Water Supply Inlet Control Switch Bin Control Thermostat Condenser (except models with Mechanical Bin Control) Hot Gas Valve Expansion Valve Fan Motor Condenser Compressor Drier Float Switch Control Box Water Pump Mechanical...
[b] KM-500MWH Spray Tubes Water Supply Inlet Control Switch Water Regulator Bin Control Thermostat (except models with Mechanical Bin Control) Expansion Valve Hot Gas Valve Compressor Float Switch Drier Water Pump Control Box Mechanical Bin Control (except models with Thermostat)
[c] KM-500MRH Spray Tubes Water Supply Inlet Control Switch Junction Box Bin Control Thermostat (except models with Mechanical Bin Control) Expansion Valve Receiver Tank Compressor Float Switch Drier Water Pump Hot Gas Valve Line Valve Control Box Mechanical Bin Control (except models with Thermostat)
2. CONTROLLER BOARD [a] SOLID-STATE CONTROL 1) A HOSHIZAKI exclusive solid-state control is employed in Modular Crescent Cubers. 2) A Printed Circuit Board (hereafter called “Controller Board”) includes a stable and high quality control system. 3) All models are pretested and factory-adjusted.
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2) 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 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.
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The green LED’s 1-4 represent the corresponding relays and energize and sequence 5 seconds from initial start-up as follows: Sequence Step LED’s on Length: Min. Max. Avg. 1 Minute Fill Cycle LED4 60 sec. Harvest Cycle LED1, 4, & 2 2 min.
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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 ener- gized with the control switch OFF, or the unit will not start.
[c] SEQUENCE 1st Cycle 1. Unit energized and Control Switch to “ICE” 3. Thermistor reads 48° F. position. Water supply cycle starts. Defrost Timer starts counting. 2. After 1 minute, Defrost cycle starts. IMPORTANT Water Valve opening is limited to 6 minutes. &...
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2nd Cycle and after with pump drain IMPORTANT Freeze cycle time is limited to 60 minutes even if Float Switch does not open. 2. Drain timer stops counting. 1. Float Switch opens and signals to complete Pump drain is completed freeze cycle.
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2nd Cycle and after with no pump drain IMPORTANT Freeze cycle time is limited to 60 minutes even if Float Switch does not open. 2. Thermistor reads 48° F. 1. Float Switch opens and signals to complete Defrost Timer starts counting. freeze cycle.
[d] CONTROLS AND ADJUSTMENTS The Dip Switch is factory-adjusted to the following positions: FOR MODELS WITH MECHANICAL BIN CONTROL: DIP SWITCH NO. OFF OFF OFF KML-500MAH OFF OFF OFF KML-500MWH OFF OFF OFF KML-500MRH FOR MODELS WITH THERMOSTAT : DIP SWITCH NO. OFF OFF OFF KML-500MAH OFF OFF OFF...
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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. 1) Defrost Control A thermistor (Semiconductor) is used for a defrost control sensor.
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2) 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.
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SETTING FREQUENCY Dip Switch Dip Switch No. 5 No. 6 every cycle every 2 cycles every 5 cycles every 10 cycles 5) Freeze Timer CAUTION Adjust to proper specification, or the unit may not operate correctly. Two new dip switches numbered 9 and 10 have been added to the improved “E” board to better prevent possible freeze ups.
MODELS WITH MECHANICAL BIN CONTROL CAUTION Dip Switch No. 7 must be set to the ON position. If No. 7 is set to the OFF position, the machine will run continuously, causing a freeze-up condition. No adjustment is required. The Bin Control is factory-adjusted. [e] CHECKING THE CONTROLLER BOARD 1) Visually check the sequence with the icemaker operating.
3) Check the Controller Board by using test program of the Controller Board. 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.
[c] TROUBLESHOOTING (MECHANICAL BIN CONTROL ONLY) 1) Machine will not start (i) Move dip switch No. 7 to the “OFF” position. If the machine starts up within a few seconds, the bin control is the likely problem. If the machine does not start up, refer to Section “IV.
IV. SERVICE DIAGNOSIS 1. NO ICE PRODUCTION PROBLEM POSSIBLE CAUSE REMEDY [1] The icemaker a) Power Supply 1. “OFF” position. 1. Move to “ON” position will not start 2. Loose connections. 2. Tighten 3. Bad contacts. 3. Check for continuity and replace.
PROBLEM POSSIBLE CAUSE REMEDY l) Controller Board 1. Defective 1. See “II.2[e] CHECKING CONTROLLER BOARD.” m) Interlock Switch 1. “OFF” position. 1. Move to “ON” position. (Cleaning Valve) 2. Bad contacts. 2. Check for continuity and replace. [2] Water a) Float switch 1.
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PROBLEM POSSIBLE CAUSE REMEDY [5] No water a) Water Supply Line 1. Water pressure too low and 1. Check and get comes from water level in Water Tank recommended pressure. Spray Tubes. too low. Water Pump b) Water Solenoid 1. Dirty mesh filter or orifice 1.
2. EVAPORATOR IS FROZEN UP PROBLEM POSSIBLE CAUSE REMEDY [1] Freeze cycle a) Float Switch 1. Leads short-circuit or 1. Check and replace. time is too defective switch. long. 2. Float does not move freely. 2. Clean or replace. b) Water Solenoid 1.
3. LOW ICE PRODUCTION PROBLEM POSSIBLE CAUSE REMEDY [1] Freeze cycle a) See chart 1 - [3], and check dirty Air Filter or Condenser, ambient or water time is long. temperature, water pressure, Water Regulator or refrigerant charge. b) See chart 2 - [1], and check Float Switch, Water Solenoid Valve or Controller Board.
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.
5) Disconnect the Vacuum Pump, and attach a Refrigerant Service Cylinder to the High-side 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 refriger- ant or reclaimed refrigerant which meets ARI Standard No. 700-88 be used.
3. 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.
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15) Evacuate the system, and charge it with refrigerant. For air-cooled and water-cooled models, see the Nameplate for the required refrigerant charge. For remote air-cooled models, see the Charge Label in the machine compartment. 16) Connect the Terminals, and replace the Terminal Cover in its correct position. 17) Replace the panels in their correct positions.
4. 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 insulation and the Expansion Valve Bulb on the suction line. 5) Remove the Expansion Valve Cover, and disconnect the Expansion Valve using brazing equipment. 6) Braze the new Expansion Valve, with nitrogen gas flowing at the pressure of 3 - 4 PSIG.
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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.
7. 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.
8. 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.
9. 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 procedures. 1) Attach a pressure gauge to the high-side line of the system. Or prepare a thermometer to check for the condenser drain temperature.
10. REMOVAL AND REPLACEMENT OF CONDENSING PRESSURE REGULATOR (C.P.R.) - REMOTE AIR-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.
11. 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 or equivalent. 3. Always use a recommended foam insulation (Non-absorbent Type) or equivalent.
Note: For models with the Liquid Bypass, the Thermistor should be located upstream from the Liquid Bypass outlet, and its end should be 4-3/4" or more away from the outlet. See Fig. 3. Min. 4-3/4" Liquid Bypass Flow Fig. 3 10) Secure the insulation using the Plastic Cable Ties.
6) Install the new Fan Motor, and replace the removed parts in the reverse order of which they were removed. 7) Replace the panels in their correct positions. 8) Replace the Junction Box Cover in its correct position (Remote Air-cooled model). 9) Turn on the power supply.
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 screws and the Pump Motor Bracket. 8) Remove the closed end connectors from the Pump Motor leads.
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. 1. 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.
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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 [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”...
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 condi- tions.
[a] CLEANING PROCEDURE 1) Dilute 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.
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19) Replace the Front Panel in its correct position. 20) Turn on the power supply to fill the Water Tank with water. 21) Turn off the power supply after 3 minutes. 22) Remove the Front Panel, and fully open the Cleaning Valve. 23) Move the Control Switch to the “Wash”...
[b] SANITIZING PROCEDURE - Following Cleaning Procedure 1) Dilute a 5.25 % Sodium Hypochlorite solution with water (Add 1.5 fl. oz. of sanitizer to 3 gal. of water). 2) Remove the Insulation Panel, if it is in its usual position. 3) Pour the sanitizing solution into the Water Tank.
3. 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 •...