Hoshizaki dcm-75ibah service manual Important Notes for Component Replacement

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5)Disconnect the gauge manifold hose from the vacuum pump and attach it to a refrigerant service cylinder. Remember to loosen the connection and purge the air from the hose. See the nameplate inside the appliance for the required refrigerant charge. Hoshizaki recommends only virgin refrigerant or reclaimed refrigerant which meets ARI Standard 700 (latest edition) be used.

6)A liquid charge is required for charging an R-404A system (to prevent fractionation). Place the service cylinder on the scales: if the service cylinder is not equipped with a dip tube, invert the service cylinder, then place it on the scales. Open the high-side valve on the gauge manifold.

7)Allow the system to charge with liquid until the proper charge weight is met.

8)If necessary, add any remaining charge to the system through the low-side.

NOTICE! To prevent compressor damage, use a throttling valve or liquid dispensing device to add the remaining liquid charge through the low-side service valve with the appliance running.

9)Close the high and low-side gauge manifold valves, then disconnect the gauge manifold hoses.

10)Cap the access valves to prevent a possible leak.

B.Important Notes for Component Replacement

NOTICE

When replacing a component listed below, see the notes to help ensure proper operation. See Fig. 14.

Component

Notes

 

 

Compressor

• Install a new drier, start capacitor, run capacitor, and start relay.

 

 

Thermostatic

• Install a new drier.

Expansion Valve

• Attach the thermostatic expansion valve bulb to the suction line in the same location as

 

the previous bulb.

 

• The bulb should be between the 10 and 2 o'clock positions on the tube.

 

• Secure the bulb with the clamp and holder, then insulate it.

 

 

Fan Motor

• Install a new fan motor capacitor.

 

 

 

Evaporator Assembly Components. See Fig. 14.

 

 

Upper and

• Inspect the upper bearing for wear. See "IV.C.1. Upper Bearing Wear Check." Replace if

Lower Bearings

necessary.

 

• When replacing the upper bearing it is advised to also change the lower bearing at the

 

same time.

Evaporator

• Install a new drier.

 

• Inspect the mechanical seal and O-ring prior to installing the new evaporator. If worn,

 

cracked, or scratched, the mechanical seal should also be replaced.

Gear Motor

• Install a new gear motor capacitor.

 

 

Extruding Head

• Extruding head allen head cap screws (with seals) are not reusable. New allen head cap

Bolts

screws (with seals) must be used.

 

 

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Contents DCM-751BAH-OS DCM-751BWH-OS Hoshizaki AMERICA, INC Contents Page Important Safety Information Page Construction and Water/Refrigeration Circuit Diagrams DCM-751BAH-OSDCM-751BWH-OS Ice Making Unit Water/Refrigeration Circuit Diagrams Spout Inlet Water Valve Water Supply Float Operation Control Board Sequence Flow Chart DCM-751BH-OSChart DiagnosisService Diagnosis Diagnostic ProcedureIce Production Check Page Page Page Page Control Board Check 5VDC CB K9 Connector See Fig High-Pressure Switch HPS5VDC CB K9 Connector Component Pin # Wire Color Gear Motor Protect Relay Gmpr 5VDC CB K8 Connector See Fig5VDC CB K8 Connector Component Pin # Wire Color Bin Control BC5VDC 0VDC Portion Signal #5 R Red K4 pin closest 5VDC Power Supply #3 W/BK 24VAC CB K2 Connector Connector Pin # Wire Color Neutral LBU Open ClosedBin Control Check Float Switch Check and Cleaning Float Switch CheckFloat Switch Cleaning Page Diagnostic Tables No Ice ProductionNo Ice Production Possible Cause Startup No Ice Production Possible Cause ShutdownIce Dispense-Opti-Serve Ice/Water DispensingIce Dispense-Push Button Water Dispense-Push ButtonIII. Controls and Adjustments Control Board Layout DCM-751BHK2 Connector Drain Valve #10 W/BU DCM-751BH-OSIcemaking Sequence Sequence Step LED Lights and Audible Alarm SafetiesNo. of Beeps Type of Alarm Reset Options Every 5 sec Energized Components Min MaxInfrared Sensor Shutdown Delay S1 dip switch 1, 2 Settings and AdjustmentsDefault Dip Switch Settings Drain Frequency Control S1 dip switchBin Control Shutdown Delay S1 dip switch Continuous Dispensing Timer S1 dip switch 5Bin Control Selector S1 dip switch Factory Use S1 Dip Switch 9OFF Power Switch, Control Switch, and Dispense Mode SwitchICE DrainDispense Mode Switch ContinuousPortion IV. Removal and Replacement of Components Service for Refrigerant LinesRefrigerant Recovery BrazingEvacuation and Recharge R-404A Important Notes for Component Replacement Evaporator Assembly Components. See FigEvaporator Assembly Icemaking Unit Upper Bearing Wear CheckRemoval and Replacement of Extruding Head Removal and Replacement of AugerRemoval and Replacement of Evaporator 5b. Lower Housing Removal and Replacement of Gear Motor Dispense Components Dispense Auger and AgitatorDispense and Agitating Motors Maintenance Maintenance ScheduleFrequency Area Task VI. Preparing the Appliance for Periods of Non-Use Page VII. Disposal VIII. Technical Information Specification Sheets DCM-751BAHDesign without prior DCM-751BWH Potable Water WATER-COOLED Condenser779 758 Reference without *marks 738 719 Performance Data ICE Production800 363 Wiring Diagrams DCM-751BH-OS