Summary of Contents for Hoshizaki CUBELET ICEMAKER/DISPENSER DCM-750BAH
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Hoshizaki America, Inc. “A Superior Degree of Reliability” www.hoshizaki.com Cubelet Icemaker / Dispenser Models DCM-750BAH DCM-750BAH-OS DCM-750BWH DCM-750BWH-OS SERVICE MANUAL ® Number: 73166 Issued: 10-8-2008...
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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, write, or send an e-mail message to the Hoshizaki Technical Support Department for assistance. HOSHIZAKI AMERICA, INC.
This manual should be read carefully before the icemaker is serviced or maintenance operations are performed. Only qualified service technicians should install, service, and maintain the icemaker. Read the warnings contained in this booklet carefully as they give important information regarding safety.
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. DCM-750BAH(-OS) ... 34 . DCM-750BWH(-OS) ... 35 IV. Service Diagnosis ... 36 A. Diagnostic Procedure ... 36 B. Ice Production Check ... 37 C. Diagnostic Charts ... 38 . No Ice Production ... 38 . Low Ice Production ... 4 3.
I. Specifications A. Icemaker 1. DCM-750BAH AC SUPPLY VOLTAGE COMPRESSOR GEAR MOTOR FAN MOTOR AGITATING MOTOR DISPENSING MOTOR OTHER MAXIMUM FUSE SIZE MAX. HACR BREAKER (USA ONLY) MAX. CIRC. BREAKER (CANADA ONLY) MINIMUM CIRCUIT AMPACITY APPROXIMATE ICE PRODUCTION PER 24 HR. lbs./day ( kg/day ) Reference without *marks SHAPE OF ICE...
2. DCM-750BAH-OS AC SUPPLY VOLTAGE COMPRESSOR GEAR MOTOR FAN MOTOR AGITATING MOTOR DISPENSING MOTOR OTHER MAXIMUM FUSE SIZE MAX. HACR BREAKER (USA ONLY) MAX. CIRC. BREAKER (CANADA ONLY) MINIMUM CIRCUIT AMPACITY APPROXIMATE ICE PRODUCTION PER 24 HR. lbs./day ( kg/day ) Reference without *marks SHAPE OF ICE ICE QUALITY...
3. DCM-750BWH AC SUPPLY VOLTAGE COMPRESSOR GEAR MOTOR AGITATING MOTOR DISPENSING MOTOR OTHER MAXIMUM FUSE SIZE MAX. HACR BREAKER (USA ONLY) MAX. CIRC. BREAKER (CANADA ONLY) MINIMUM CIRCUIT AMPACITY APPROXIMATE ICE PRODUCTION PER 24 HR. lbs./day ( kg/day ) Reference without *marks SHAPE OF ICE ICE QUALITY APPROXIMATE STORAGE CAPACITY...
4. DCM-750BWH-OS AC SUPPLY VOLTAGE COMPRESSOR GEAR MOTOR AGITATING MOTOR DISPENSING MOTOR OTHER MAXIMUM FUSE SIZE MAX. HACR BREAKER (USA ONLY) MAX. CIRC. BREAKER (CANADA ONLY) MINIMUM CIRCUIT AMPACITY APPROXIMATE ICE PRODUCTION PER 24 HR. lbs./day ( kg/day ) Reference without *marks SHAPE OF ICE ICE QUALITY APPROXIMATE STORAGE CAPACITY...
II. General Information A. Construction 1. DCM-750BAH(-OS) Evaporator Assembly Inlet Water Valve Float Switch Reservoir Control Box Power Switch Gear Motor Door Switch Drain Water Valve Agitating Motor (L) Control Switch Dispense Mode Switch Air-Cooled Condenser Shutter Assembly Spout Cover Expansion Valve Spout A Spout B...
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2. DCM-750BWH(-OS) Inlet Water Valve Float Switch Reservoir Control Box Power Switch Door Switch Gear Motor Drain Water Valve Agitating Motor (L) Control Switch Dispense Mode Switch Shutter Assembly Water-Cooled Condenser Evaporator Assembly Expansion Valve Spout A Spout Cover Drier Spout B Storage Bin Bin Control Switch...
B. Ice Making Unit 1. DCM-750BAH(-OS) Extruding Head and Upper Bearing Allen Head Cap Screw Washer Auger Cylinder Evaporator Insulation Mechanical Seal Capacitor O-Ring Gear Motor Cubelet Cutter Housing and Lower Bearing Extruding Head Heater Allen Head Cap Screw with Washer Hex Head Bolt with Washer...
C. Sequence of Operation The steps in the sequence are as outlined below. When power is supplied, the power switch is in the "ON" position, the door switch is engaged, and the control switch is in the "ICE" position, the "POWER" LED on the control board comes on. 1.
D. Control Board • A Hoshizaki exclusive solid-state control board is employed in DCM-750BAH, DCM-750BAH-OS, DCM-750BWH, and DCM-750BWH-OS Cubelet Icemaker / Dispensers. • All models are pretested and factory-adjusted. . Fragile, handle very carefully. . The control board contains integrated circuits, which are susceptible to failure due to static discharge.
1. Control Board Layout a) DCM-750BAH, DCM-750BWH Flush Switch Must be left in the "P" position, otherwise the internal drain timer will not operate. Counter Reset Button (not used in this application) Portion Control Timer "FLUSH" LED (X5 Relay) Drain Valve 4V Supply Out Drain Valve 4V In...
b) DCM-750BAH-OS, DCM-750BWH-OS Flush Switch Must be left in the "P" position, otherwise the internal drain timer will not operate. Counter Reset Button (not used in this application) Portion Control Timer "WTR" LED (X5 Relay) Dispensing Water Valve "FLUSH" LED (X6 Relay) Drain Valve 4V Supply Out...
2. Features The control board provides the following safeguards: • Provides component protection during low water supply. • Purges remaining ice in the evaporator at startup and shutdown. • Provides short cycle protection for the compressor. a) LED Lights The "POWER" LED indicates control voltage and will remain on unless a control voltage problem occurs.
3. Controls and Adjustments a) Portion Control When the dispense mode switch is placed in the "PORTION" position, a variable resistor (located on the control board) controls the ice dispense time. The figures on the label indicate dispensing time (sec.). When shipped, the portion control is set at the minimum dispensing time (0.6 sec.).
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3. 60 seconds after the "GM" LED comes on, the "COMP" LED comes on, and the compressor and fan motor start. If the "COMP" LED does not come on 60 seconds after the gear motor starts, check that the gear motor protect relay contacts (connector K terminals and ) have closed.
E. Float Switch Depending on local water conditions, scale may build up on the float switch. Scale on the switch can cause the floats to stick. In this case, the float switch should be cleaned and checked. First, remove the switch from the water tank. Soak the switch assembly in ice machine cleaner.
III. Technical Information A. Water Circuit and Refrigeration Circuit 1. DCM-750BAH(-OS) Spout Inlet Water Valve Water Supply Float Switch Water Level Reservoir Evaporator Overflow Drier Expansion Valve To Drain Drain Valve Gear Motor Dispensing Water Valve High Pressure Switch Air-Cooled Condenser Access Valve Access Valve Compressor...
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2. DCM-750BWH(-OS) Inlet Water Valve Water Supply Reservoir Overflow Water Supply In Water Supply Out Water Regulating Valve Float Switch Water Level Evaporator Gear Motor Water-Cooled Condenser Access Valve Refrigeration Circuit Water Circuit Spout Drier Expansion Valve To Drain Drain Valve Dispensing Water Valve High Pressure Switch Access Valve...
B. Wiring Diagrams 1. DCM-750BAH, DCM-750BWH WIRE COLOR CODE BLACK BROWN BLUE DARK BLUE GRAY LIGHT BLUE ORANGE PINK VIOLET WHITE YELLOW W/BK WHITE/BLACK W/BR WHITE/BROWN W/BU WHITE/BLUE WHITE/ORANGE WHITE/RED * High Pressure Switch Air-Cooled Model Cut-out 412± PSIG Cut-in 327±21 PSIG Water-Cooled Model 384±...
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2. DCM-750BAH-OS, DCM-750BWH-OS WIRE COLOR CODE BLACK BROWN BLUE DARK BLUE GRAY LIGHT BLUE ORANGE PINK VIOLET WHITE YELLOW W/BK WHITE/BLACK W/BR WHITE/BROWN W/BU WHITE/BLUE WHITE/ORANGE WHITE/RED * High Pressure Switch Air-Cooled Model Cut-out 412± PSIG Cut-in 327±21 PSIG Water-Cooled Model 384±...
C. Sequence of Electrical Circuit – Ice Making 1. Fill Cycle With the power switch in the "ON" position and the control switch in the "ICE" position, the inlet water valve energizes and the reservoir fills with water until the upper float switch closes.
2. Ice Purge Cycle Upper float switch closes, water control relay energizes, inlet water valve closes, gear motor starts, gear motor protect relay energizes. DCM-750BAH, DCM-750BWH WIRE COLOR CODE BLACK ORANGE W/BK WHITE/BLACK BROWN PINK W/BR WHITE/BROWN BLUE W/BU WHITE/BLUE DARK BLUE VIOLET WHITE/ORANGE...
3. Freeze Cycle Compressor and fan motor start 60 seconds after gear motor starts. DCM-750BAH, DCM-750BWH WIRE COLOR CODE BLACK ORANGE W/BK WHITE/BLACK BROWN PINK W/BR WHITE/BROWN BLUE W/BU WHITE/BLUE DARK BLUE VIOLET WHITE/ORANGE GRAY WHITE WHITE/RED LIGHT BLUE YELLOW DCM-750BAH-OS, DCM-750BWH-OS...
4. 12 Hour Drain Cycle / Drain Switch hour timer initiates cycle or the control switch is moved to the "DRAIN" position. 90 seconds after initiation, the compressor and condenser fan motor stop, 60 seconds later the gear motor stops. Once the gear motor protect relay de-energizes, the drain water valve opens.
5. Shutdown The bin control switch is activated and a 50 second shutdown sequence begins. After the bin control has been open for 90 seconds, the compressor and fan motor stop, the agitating motor operates for 0.6 seconds, and 60 seconds later the gear motor stops. DCM-750BAH, DCM-750BWH WIRE COLOR CODE...
6. Low Water Safety Upper float switch fails to close within 90 seconds after the lower float switch opens, the 50 second shutdown sequence begins. The inlet water valve remains open until the upper float switch closes. DCM-750BAH, DCM-750BWH WIRE COLOR CODE BLACK ORANGE W/BK WHITE/BLACK...
7. High Pressure Switch When the high pressure switch opens, the compressor stops immediately, 60 seconds later the gear motor stops. To restart, allow time for the high pressure switch to close, then move the power switch to the "OFF" position and then back to the "ON" position. DCM-750BAH, DCM-750BWH WIRE COLOR CODE...
D. Sequence of Electrical Circuit – Dispensing 1. Continuous Dispense Agitating motor energizes for .6 seconds for every seconds of accumulative dispense time. Maximum dispense time per dispense switch activation is 60 seconds. After 60 seconds, the dispense switch must be disengaged and engaged again. DCM-750BAH, DCM-750BWH WIRE COLOR CODE...
2. Portion Dispense Agitating motor energizes for .6 seconds for every seconds of accumulative dispense time. A variable resistor which controls the amount of ice dispensed is located on the control board. The figures on the label indicate dispensing time (sec.). See "II. D.3.a) Portion Control."...
E. Performance Data 1. DCM-750BAH(-OS) APPROXIMATE ICE PRODUCTION PER 24 HR. lbs./day (kg/day) APPROXIMATE ELECTRIC CONSUMPTION watts APPROXIMATE WATER CONSUMPTION PER 24 HR. gal./day (l/day) EVAPORATOR OUTLET TEMP. °F (°C) HEAD PRESSURE PSIG (kg/cm²G) SUCTION PRESSURE PSIG ( kg/cm²G ) TOTAL HEAT OF REJECTION Note: .
2. DCM-750BWH(-OS) APPROXIMATE ICE PRODUCTION PER 24 HR. lbs./day ( l/day) APPROXIMATE ELECTRIC CONSUMPTION watts APPROXIMATE WATER CONSUMPTION PER 24 HR. (TOTAL) gal. / day (kl/day) EVAPORATOR OUTLET TEMP. °F (°C) HEAD PRESSURE PSIG (kg/cm SUCTION PRESSURE PSIG (kg/cm WATER FLOW FOR CONDENSER PRESSURE DROP OF COOLING WATER LINE HEAT OF REJECTION FROM CONDENSER HEAT OF REJECTION FROM COMPRESSOR...
IV. Service Diagnosis A. Diagnostic Procedure This diagnostic procedure is a sequence check that allows you to diagnose the electrical system and components. Before proceeding, check for correct installation, adequate water supply (minimum of 0 PSIG, maximum of 3 PSIG) and proper voltage per unit nameplate.
6) Refill /Low Water Safety – As ice is produced, the water level in the reservoir drops. As the water level drops, the upper and lower float switches open. First, the upper float switch opens. Nothing occurs at this time. When the lower float switch opens, refill begins.
C. Diagnostic Charts 1. No Ice Production Problem Possible Cause [] The icemaker will not a) Power Supply start. (Fill Cycle) b) Water Supply c) Power Switch (Control Box) d) Door Switch e) Power Protect Relay f) Transformer g) Fuses () h) Control Switch i) Water Control Relay j) Inlet Water Valve...
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Problem Possible Cause [] The icemaker will m) High Pressure Switch not start. (Fill Cycle) (continued) n) Plug and Receptacle (Control Box) o) Control Board [] Fill cycle will not a) Water Supply terminate. b) Float Switch c) Water Control Relay d) Drain Valve e) Hoses f) Control Board...
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Problem Possible Cause [3] Ice purge cycle will a) Water Control Relay not start. b) Control Switch c) Bin Control d) Control Board e) Gear Motor Fuse f) Gear Motor Thermal Protector g) Gear Motor [4] Freeze cycle will not a) Gear Motor Protect start (compressor).
Problem Possible Cause [5] All components d) Evaporator run, but no ice is e) Water Supply Line produced. (continued) (water-cooled model only) f) Water Regulating Valve (water-cooled model only) 2. Low Ice Production Problem Possible Cause [] Low ice production. a)Evaporator b)Bin Control c) Drain Valve...
3. Other Problem Possible Cause [] Icemaker will not stop a)Bin Control when bin is filled with ice. [] Abnormal noise. a)Fan Motor (except water-cooled model) b)Compressor c) Refrigerant Lines d)Auger e)Gear Motor f) Evaporator g)Extruding Head Heater . Heater Control Relay [3] Overflow from a)Water Supply reservoir (water does...
Problem Possible Cause [4] Gear motor overload a)Power Supply protector operates frequently or fuse b)Evaporator Assembly blows frequently. c) Bin Control d)Safety Switch and Relay e)Control Board 4. Dispensing Problem Possible Cause [] No ice dispensed. a) Power Supply b) Ice Storage c) Ice Dispense Switch d) Shutter Assembly e) Dispense Gear Motor...
Problem Possible Cause [] Abnormal noise. a) Gear Motor or Gear Head b) Auger Mechanism c) Dispense Water Solenoid [3] No water dispensed. a) Power Supply b) Water Supply c) Dispensing Water Valve d) Control Board e) Water Dispense Switch . Opti Serve sensor 5.
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Problem Possible Cause [] No water dispensed. a) OS Sensor b) Dispense Mode Switch . Wrong setting. c) Control Board 5a. Ice Dispensing "Continuous" Mode Component Control Board Solenoid K Pin 6 LBU Sensor K5 Pin 4 W/0 5b. Ice Dispensing "Portion" Mode Component Control Board Solenoid...
V. Removal and Replacement of Components . Ensure all components, fasteners, and thumbscrews are securely in place after the equipment is serviced. . 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 refrigerant or reclaimed refrigerant which meets ARI Standard No. 700-88 be used.
B. Removal and Replacement of Compressor 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.
C. Removal and Replacement of Expansion Valve Sometimes moisture in the refrigeration 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.
D. Removal and Replacement of Evaporator Assembly Components Make sure the extruding head heater is installed and connected after service. Evaporator Assembly Power Switch Control Switch Dispense Mode Switch Fig. 1 CAUTION Spout A Spout B Allen Head Cap Screw Washer Evaporator Strap Allen Head Cap Screw...
1. Upper Bearing Wear Check To ensure that the bearing inside the extruding head does not exceed the wear tolerance of .0", follow the instructions below. See Fig. . ) Move the control switch to the "OFF" position, then turn off the power supply. Remove the front and top panels, then move the power switch to the "OFF"...
8) Replace spout A, spout B, and the front cover of the storage bin in their correct positions. 9) Move the power switch to the "ON" position, then replace the panels in their correct positions. 0) Turn on the power supply, then move the control switch to the "ICE" position to start the automatic icemaking process.
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3) Remove the apron panel, then remove the left side panel. 4) Recover the refrigerant and store it in an approved container. 5) Disconnect the drip tray hose from the tee. Remove the four screws securing the drip tray, then remove the drip tray and hose. 6) Remove the front cover of the storage bin.
5. Removal and Replacement of Mechanical Seal and Lower Housing 5a. Mechanical Seal ) Move the control switch to the "DRAIN" position and drain all of the water from the evaporator. ) After the water has stopped draining, move the control switch to the "OFF" position, then turn off the power supply.
8) Move the power switch to the "ON" position, then replace the panels in their correct positions. 9) Turn on the power supply, then move the control switch to the "ICE" position to start the automatic icemaking process. 6. Removal and Replacement of Gear Motor ) Move the control switch to the "DRAIN"...
E. Removal and Replacement of Self-Contained Air-Cooled Condenser 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. ) Move the control switch to the "OFF" position, then turn off the power supply. Remove the front and top panels, then move the power switch to the "OFF"...
F. Removal and Replacement of Water-Cooled Condenser 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. ) Move the control switch to the "OFF" position, then turn off the power supply. Remove the front and top panels, then move the power switch to the "OFF"...
G. Removal and Replacement of Water Regulating Valve - Water-Cooled Model Only 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. ) Move the control switch to the "OFF"...
0) Move the power switch to the "ON" position, then replace the panels in their correct positions. ) Turn on the power supply, then move the control switch to the "ICE" position to start the automatic icemaking process. H. Adjustment of Water Regulating Valve - Water-Cooled Model Only The water regulating valve (also called "water regulator") is factory-adjusted.
J. Removal and Replacement of Inlet or Dispensing Water Valve ) Close the water supply line shut-off valve. ) Open the water supply line drain valve. 3) Move the control switch to the "OFF" position, then turn off the power supply. Remove the front and top panels, then move the power switch to the "OFF"...
0) Open the water supply line shut-off valve. ) Turn on the power supply, move the power switch to the "ON" position, then replace the front panel in its correct position to engage the door switch. Move the control switch to the "ICE"...
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6) Install the new motor. 7) Assemble the removed parts in the reverse order of which they were removed. 8) Move the power switch to the "ON" position, then replace the panels in their correct positions. 9) Turn on the power supply, then move the control switch to the "ICE" position to start the automatic icemaking process.
A. Cleaning and Sanitizing Instructions HOSHIZAKI recommends cleaning this unit at least twice a year. More frequent cleaning, however, may be required in some existing water conditions. . To prevent injury to individuals, do not use any ammonia type cleaners.
1. Water System a) Cleaning Solution Dilute 9.6 fl. oz. (0.9 l) of recommended cleaner, Hoshizaki "Scale Away" or "LIME-A- WAY" (Economics Laboratory, Inc.), with .6 gal. (6.0 l) of warm water. b) Cleaning Procedure ) Close the water supply line shut-off valve.
Perform after cleaning and sanitizing the water system as outlined above. a) Cleaning Solution Dilute 9.6 fl. oz. (0.9 l) of recommended cleaner, Hoshizaki "Scale Away" or "LIME-A- WAY" (Economics Laboratory, Inc.), with .6 gal. (6.0 l) of warm water.
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3) Remove the front cover of the storage bin. 4) Remove the motor bracket thumbscrews, first from the vertical plane and then from the horizontal plane. While holding on to the corresponding agitator or auger, move the agitating motor or the dispensing motor towards you. Remove the agitators and the dispensing auger from the storage bin.
Consult with your local distributor about inspection and maintenance service. To obtain the name and phone number of your local distributor, visit www.hoshizaki.com or call Hoshizaki Technical Support at -800-33-940 in the USA. . Only qualified service technicians should attempt to service or maintain this icemaker.
C. Preparing the Icemaker for Long Storage When the icemaker is not used for two or three days under normal conditions, it is sufficient to only move the control switch to the "OFF" position. When storing the icemaker for extended time or in sub-freezing temperatures, turn the water off and drain out all water from the water lines and remove the ice from the storage bin.
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2. On water-cooled model only, remove the water from the water-cooled condenser: ) Make sure the control switch and the power switch are in the "OFF" position and that the power supply is off. Remove the top, apron, and left side panels. ) Close the condenser water supply line shut-off valve and open the condenser water supply line drain valve.
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