Hoshizaki DCM-750BAH-OS manual

 Hoshizaki “A Superior Degree of Reliability” www .hoshizaki.com Models DCM-750BAH DCM-750BAH-OS DCM-750BWH DCM-750BWH-OS Cubelet Icemaker / Dispenser Hoshizaki America, Inc. Number: 73166 Issued: 10-8-2008 S E RV I C E M A N U A L ®[...]

 IMPORTANT Only qualied service technicians should attempt to install, service, or maintain this icemaker. No service or maintenance should be undertaken until the technician has thoroughly read this Service Manual. Failure to service and maintain the equipment in accordance with this manual may adversely affect safety, performance, and warra[...]

3 IMPORTANT This manual should be read carefully before the icemaker is serviced or maintenance operations are performed. Only qualied service technicians should install, service, and maintain the icemaker. Read the warnings contained in this booklet carefully as they give important information regarding safety. Please retain this booklet for an[...]

4 E. Performance Data ....................................................................................................... 34 . DCM-750BAH(-OS) ............................................................................................... 34 . DCM-750BWH(-OS) ................................................................................[...]

5 I. Specications A. Icemaker 1. DCM-750BAH Note: We reserve the right to make changes in specications and design without prior notice. AC SUPPLY VOLTAGE 115/60/1 COMPRESSOR 120 V 13.2 RLA 60 LRA GEAR MOTOR 120 V 3 FLA 1/4 HP FAN MOTOR 120 V 0.85 FLA 1/15 HP AGITATING MOTOR 120 V 1.8 FLA (Total) 110 W DISPENSING MOTOR 120 V 0.9 FLA 55 W OTHER[...]

6 2. DCM-750BAH-OS Note: We reserve the right to make changes in specications and design without prior notice. AC SUPPLY VOLTAGE 115/60/1 COMPRESSOR 120 V 13.2 RLA 60 LRA GEAR MOTOR 120 V 3 FLA 1/4 HP FAN MOTOR 120 V 0.85 FLA 1/15 HP AGITATING MOTOR 120 V 1.8 FLA (Total) 110 W DISPENSING MOTOR 120 V 0.9 FLA 55 W OTHER 120 V 0.6 A MAXIMUM FUSE SI[...]

7 Note: We reserve the right to make changes in specications and design without prior notice. 3. DCM-750BWH AC SUPPLY VOLTAGE 115/60/1 COMPRESSOR 120 V 13.2 RLA 60 LRA GEAR MOTOR 120 V 3 FLA 1/4 HP AGITATING MOTOR 120 V 1.8 FLA (Total) 110 W DISPENSING MOTOR 120 V 0.9 FLA 55 W OTHER 120 V 0.6 A MAXIMUM FUSE SIZE 20 A MAX. HACR BREAKER (USA ONLY)[...]

8 4. DCM-750BWH-OS Note: We reserve the right to make changes in specications and design without prior notice. AC SUPPLY VOLTAGE 115/60/1 COMPRESSOR 120 V 10 RLA 60 LRA GEAR MOTOR 120 V 3 FLA 1/4 HP AGITATING MOTOR 120 V 1.8 FLA (Total) 110 W DISPENSING MOTOR 120 V 0.9 FLA 55 W OTHER 120 V 0.6 A MAXIMUM FUSE SIZE 20 A MAX. HACR BREAKER (USA ONLY[...]

9 II. General Information A. Construction 1. DCM-750BAH(-OS) Storage Bin Inlet Water Valve Reservoir Control Box Air-Cooled Condenser Spout Cover Evaporator Assembly Compressor Dispensing Motor Agitator (L) Dispensing Auger Dispensing Water Valve Spout B Float Switch Dispense Mode Switch Control Switch Shutter Assembly Power Switch Drier Spout A Dr[...]

0 2. DCM-750BWH(-OS) Storage Bin Inlet Water Valve Reservoir Control Box Water-Cooled Condenser Spout Cover Evaporator Assembly Compressor Dispensing Motor Agitator (L) Dispensing Auger Dispensing Water Valve Spout B Float Switch Dispense Mode Switch Control Switch Shutter Assembly Power Switch Drier Spout A Drain Water Valve Door Switch Expansi[...]

 B. Ice Making Unit 1. DCM-750BAH(-OS) Cubelet Cutter Allen Head Cap Screw Gear Motor O-Ring Mechanical Seal Extruding Head and Upper Bearing Hex Head Bolt with Washer Auger Evaporator Housing and Lower Bearing Cylinder Insulation Allen Head Cap Screw with Washer Washer Extruding Head Heater Capacitor[...]

 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. Fill Cycle WV opens and the reservoir lls w[...]

3 Legend: BC - bin control Comp - compressor DC - drain cycle DT - drain timer DV - drain valve FMS - self-contained fan motor FT - ll timer (low water safety) GM - gear motor GMPR - gear motor protect relay HCR - heater control relay HTR - extruding head heater LF/S - lower oat switch UF/S - upper oat switch WCR - water control relay W[...]

4 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. CAUTION . Fragile, handle very carefully. . The control board contains integrated circuits, which are susceptible to[...]

5 Microprocessor (board revision level indicated by last  digits on label) "POWER" LED (lights when power is supplied to the board) "FLUSH" LED (X5 Relay) Drain Valve "COMP" LED (X Relay) Compressor, Fan Motor 0.5V Transformer "GM" LED (X Relay) Gear Motor "DM" LED (X4 Relay) Shutter [...]

6 Dispensing Components See "III.B. Wiring Diagrams" for details. Bin Control, Control Switch, Low Water Safety Microprocessor (board revision level indicated by last  digits on label) "POWER" LED (lights when power is supplied to the board) "FLUSH" LED (X6 Relay) Drain Valve "COMP" LED (X Relay) Com[...]

7 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 con[...]

8 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 gures on the label indicate dispensing time (sec.). When shipped, the portion control is set at the minimum dispensing time (0.6 se[...]

9 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. If the "COMP" LED is [...]

0 E. Float Switch Depending on local water conditions, scale may build up on the oat switch. Scale on the switch can cause the oats to stick. In this case, the oat switch should be cleaned and checked. First, remove the switch from the water tank. Soak the switch assembly in ice machine cleaner. While not necessary, the oats can be r[...]

 III. Technical Information A. Water Circuit and Refrigeration Circuit 1. DCM-750BAH(-OS) Inlet Water Valve Dispensing Water Valve Drain Valve Float Switch Water Level To Drain Evaporator Spout Expansion Valve Gear Motor Overow Reservoir Water Supply Drier Air-Cooled Condenser Fan High Pressure Switch Access Valve Access Valve Compressor R[...]

 2. DCM-750BWH(-OS) Inlet Water Valve Dispensing Water Valve Drain Valve Float Switch Water Level To Drain Evaporator Spout Expansion Valve Gear Motor Overow Reservoir Water Supply Drier Water-Cooled Condenser High Pressure Switch Access Valve Access Valve Compressor Water Supply In Water Supply Out Refrigeration Circuit Water Circuit Wate[...]

3 BK BLACK BR BROWN BU BLUE DBU DARK BLUE GY GRAY LBU LIGHT BLUE O ORANGE P PINK R RED V VIOLET W WHITE Y YELLOW W/BK WHITE/BLACK W/BR WHITE/BROWN W/BU WHITE/BLUE W/O WHITE/ORANGE W/R WHITE/RED WIRE COLOR CODE * B. Wiring Diagrams 1. DCM-750BAH, DCM-750BWH * High Pressure Switch Air-Cooled Model W ater-Cooled Model Cut-out 412± 21 PSIG 384± 21[...]

4 2. DCM-750BAH-OS, DCM-750BWH-OS BK BLACK BR BROWN BU BLUE DBU DARK BLUE GY GRAY LBU LIGHT BLUE O ORANGE P PINK R RED V VIOLET W WHITE Y YELLOW W/BK WHITE/BLACK W/BR WHITE/BROWN W/BU WHITE/BLUE W/O WHITE/ORANGE W/R WHITE/RED WIRE COLOR CODE * * High Pressure Switch Air-Cooled Model W ater-Cooled Model Cut-out 412± 21 PSIG 384± 21 PSIG Cut-in [...]

5 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 lls with water until the upper oat switch closes. DCM-750BAH-OS, DCM-750BWH-OS DCM-750BAH, DCM-750BWH BK BLACK O ORAN[...]

6 2. Ice Purge Cycle Upper oat switch closes, water control relay energizes, inlet water valve closes, gear motor starts, gear motor protect relay energizes. BK BLACK O ORANGE W/BK WHITE/BLACK BR BROWN P PINK W/BR WHITE/BROWN BU BLUE R RED W/BU WHITE/BLUE DBU DARK BLUE V VIOLET W/O WHITE/ORANGE GY GRAY W WHITE W/R WHITE/RED LBU LIGHT BLUE Y Y[...]

7 3. Freeze Cycle Compressor and fan motor start 60 seconds after gear motor starts. BK BLACK O ORANGE W/BK WHITE/BLACK BR BROWN P PINK W/BR WHITE/BROWN BU BLUE R RED W/BU WHITE/BLUE DBU DARK BLUE V VIOLET W/O WHITE/ORANGE GY GRAY W WHITE W/R WHITE/RED LBU LIGHT BLUE Y YELLOW WIRE COLOR CODE DCM-750BAH-OS, DCM-750BWH-OS DCM-750BAH, DCM-750BWH[...]

8 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. In the  hou[...]

9 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. BK BLACK O ORANGE W/BK WHITE/BLACK BR BROWN P PINK W/BR WHITE/BROWN BU BLUE [...]

30 6. Low Water Safety Upper oat switch fails to close within 90 seconds after the lower oat switch opens, the 50 second shutdown sequence begins. The inlet water valve remains open until the upper oat switch closes. BK BLACK O ORANGE W/BK WHITE/BLACK BR BROWN P PINK W/BR WHITE/BROWN BU BLUE R RED W/BU WHITE/BLUE DBU DARK BLUE V VIOLET [...]

3 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. BK BLACK O ORANGE W/BK WHITE/BLACK BR BROWN [...]

3 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. BK BLACK O ORANGE W/BK WHITE/BLA[...]

33 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 gures on the label indicate dispensing time (sec.). See "II. D.3.a) Portion Control." When shipped, the portion contr[...]

34 E. Performance Data 1. DCM-750BAH(-OS) Note: . The data without *marks should be used for reference only. . We reserve the right to make changes in specications and design without prior notice. APPROXIMATE Ambient Water Temp. (°F) ICE PRODUCTION Temp. (°F ) PER 24 HR. 70 *803 *(364) 770 (349) 726 (329) 80 684 (310) 645 (293) 608 (276)[...]

35 2. DCM-750BWH(-OS) Note: . The data without *marks should be used for reference only. . We reserve the right to make changes in specications and design without prior notice. APPROXIMATE Ambient Water Temp. (F) ICE PRODUCTION Temp. (F) PER 24 HR. 70 * 744 337 719 326 708 321 80 696 316 684 310 673 305 90 662 300 * 654 297 640 291 lbs./da[...]

36 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. Always choose a white neutral[...]

37 6) Rell /Low Water Safety – As ice is produced, the water level in the reservoir drops. As the water level drops, the upper and lower oat switches open. First, the upper oat switch opens. Nothing occurs at this time. When the lower oat switch opens, rell begins. The water control relay de-energizes, the 90 second low water safet[...]

38 C. Diagnostic Charts 1. No Ice Production Problem Possible Cause Remedy [] The icemaker will not start. (Fill Cycle) a) Power Supply . Off, blown fuse, or tripped breaker. . Turn on, replace, or reset. . Loose connection. . Tighten. 3. Bad contacts. 3. Check for continuity and replace. 4. Not within specications. 4. Refer to na[...]

39 Problem Possible Cause Remedy [] The icemaker will not start. (Fill Cycle) (continued) m) High Pressure Switch . Bad contacts. . Check for continuity and replace. . Dirty air lter or condenser. . Clean. 3. Ambient or condenser water temperature too warm. 3. Reduce temperature. 4. Refrigerant overcharged. 4. Recover, evacuate, a[...]

40 Problem Possible Cause Remedy [3] Ice purge cycle will not start. a) Water Control Relay . Low water safety circuit open (bad contacts ). . Replace. b) Control Switch . Bad contacts. . Check for continuity and replace. c) Bin Control . Open. . Bin full, check for continuity on proximity switch. d) Control Board . Fails to op[...]

4 Problem Possible Cause Remedy [5] All components run, but no ice is produced. (continued) d) Evaporator . Defective. . Replace. e) Water Supply Line (water-cooled model only) . Condenser water pressure too low or off and high pressure control opens and closes frequently. . Check and get recommended pressure. f) Water Regulating Val[...]

4 3. Other Problem Possible Cause Remedy [] Icemaker will not stop when bin is lled with ice. a) Bin Control . Actuator sticking. . Adjust or replace. . Proximity switch closed. . Replace. [] Abnormal noise. a) Fan Motor (except water-cooled model) . Bearing worn out. . Replace. . Fan blade deformed. . Replace fa[...]

43 Problem Possible Cause Remedy [4] Gear motor overload protector operates frequently or fuse blows frequently. a) Power Supply . Not within specications. . Refer to nameplate and correct. b) Evaporator Assembly . Bearings or auger worn out. . Replace bearings or auger. See "V.F.. Upper Bearing Wear Check." c) Bin Contr[...]

44 Problem Possible Cause Remedy [] Abnormal noise. a) Gear Motor or Gear Head . Bearing worn out. . Replace. b) Auger Mechanism . Bad alignment of auger. . Realign. . Foreign matter interrupting agitator. . Remove foreign matter. c) Dispense Water Solenoid . Vibration due to loosening screws. . Apply thread sealant to th[...]

45 Problem Possible Cause Remedy [] No water dispensed. a) OS Sensor . Dirty sensor. . Clean. . Defective. . See chart 5c below. b) Dispense Mode Switch . Wrong setting. . Move to desired setting. . Bad contacts. . Check for continuity and replace. 3. Loose connection. 3. Tighten. c) Control Board . Loose connection. ?[...]

46 V. Removal and Replacement of Components IMPORTANT . 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 part[...]

47 ) 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. Install the new drier with the arrow on the drier in the direction of the refrigerant ow. ) Braze all ttings while purging with nitrogen gas owing at a pressure of 3[...]

48 B. 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 wit[...]

49 C. Removal and Replacement of Expansion Valve IMPORTANT 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. ) Move th[...]

50 Fig. 1 Extruding Head and Upper Bearing Evaporator Allen Head Cap Screw with Washer Allen Head Cap Screw Housing and Lower Bearing Gear Motor Barrier/Capacitor O-Ring Mechanical Seal Auger Cutter Hex Head Bolt with Washer D. Removal and Replacement of Evaporator Assembly Components CAUTION Make sure the extruding head heater is installed and con[...]

5 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 "O[...]

5 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. 3. Re[...]

53 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. Remove spout B, then remove spout A. See Fig.[...]

54 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. Remove the front and[...]

55 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" posit[...]

56 E. Removal and Replacement of Self-Contained Air-Cooled Condenser 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. ) Move the control switch to the "OFF" position, then turn off the power supply. Remove the[...]

57 F. Removal and Replacement of Water-Cooled Condenser 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. ) Move the control switch to the "OFF" position, then turn off the power supply. Remove the front and top [...]

58 G. 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. ) Move the control switch to the "OFF" position, then turn off the power supply.[...]

59 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[...]

60 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" position. 4) Rem[...]

6 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" position. ) Allow the icemaker to ll for two minutes. 3) Move the con[...]

6 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.[...]

63 VI. Cleaning and Maintenance IMPORTANT Ensure all components, fasteners, and thumbscrews are securely in place after any cleaning or maintenance is done to the equipment. 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 c[...]

64 1. Water System a) Cleaning Solution Dilute 9.6 . 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. ) Move the dispense mode switch to the "CONTINU[...]

65 3) Move the control switch to the "OFF" position, then turn off the power supply. 4) Close the water supply line shut-off valve. c) Sanitizing Solution Dilute 0.8 . oz. (5 ml) of a 5.5% sodium hypochlorite solution (chlorine bleach) with .6 gal. (6.0 l) of warm water. d) Sanitizing Procedure - Following Cleaning Pr[...]

66 3) Remove the front cover of the storage bin. 4) Remove the motor bracket thumbscrews, rst 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. See Fi[...]

67 B. Maintenance This icemaker must be maintained individually, referring to the instruction manual and labels provided with the icemaker. The schedule below is a guideline. More frequent maintenance, however, may be required depending on water quality, the icemaker's environment, and local sanitation regulations. Consult with your local dist[...]

68 C. Preparing the Icemaker for Long Storage CAUTION When the icemaker is not used for two or three days under normal conditions, it is sufcient 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 l[...]

69 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 li[...]