Hoshizaki dcm-75ibah service manual

Page 14

7)Startup–"POWER OK" LED is on: Move the power switch to the "ON" position, then move the control switch to the "ICE" position. CB "POWER OK" LED is on. "POWER OK" LED Diagnosis: Check that CB "POWER" LED is on. If not, check for proper power supply voltage (115VAC) input to CT. If 115VAC is not present, check the breaker, power switch, and safety switch. Next, check that the power protect relay is deenergized and contacts between terminals #6 (BR) and #2 (BK) are closed. Check for proper control voltage (24VAC) output from CT. Next, check the 24VAC 1A fuse. If open, replace. Check for 24VAC at CB K8 connector pin #1 (W/R) to CB K8 connector pin #2 (LBU). If 24VAC is not present at CB K8 connector pin #1 (W/R) but is present at 1A fuse (W/R), check continuity of control switch. If open, replace. If 24VAC is present between CB K8 connector pin #1 (W/R) and pin #2 (LBU), and "POWER OK" LED is off, replace CB.

BC Diagnosis: Check that the actuator paddle is properly positioned. Check for continuity across BC proximity switch. When BC proximity switch is closed 0VDC is read across CB K8 connector pin #3 (GY) and #4 (GY). 5VDC is present between CB K8 connector pin #3 (GY) or #4 (GY) to CB red K4 connector pin closest to CB black K3 black connector (5VDC GND). If 5VDC is not present, replace CB.

HPS Diagnosis: HPS automatically resets when refrigeration circuit high-side pressure is within an acceptable range. 5VDC is supplied from CB K9 connector pin #3 (Y) and back onto CB K9 connector pin #4 (Y). If 5VDC is not present at CB K9 connector pin #3 (Y) to CB red K4 connector pin closest to CB black K3 connector (5VDC GND) and CB "POWER OK" LED is on, replace CB. If refrigerant pressures have returned to an acceptable range and HPS does not close, replace HPS. If pressures have not equalized, and refrigeration circuit high-side pressure does not drop, recover, evacuate, and recharge if necessary. On air-cooled model, check that the condenser is not dirty or clogged, check for proper FM operation and fan blade for binding. On water-cooled model, check WRV and water flow in and out of condenser. Check for refrigeration circuit refrigerant restriction (TXV and drier).

8)Fill Cycle"WTRIN" LED is on: WV energizes. 90-sec. FT starts. LFS closes. Nothing happens at this time. Reservoir continues to fill. UFS closes, WV deenergizes, 90sec. FT terminates. Diagnosis: If the reservoir is empty, LFS open, "WTRIN" LED on, and WV off, check for 24VAC at CB K2 connector pin #8 (W/BR) to a neutral (LBU).

If 24VAC is not present, confirm 24VAC power supply at CB K2 connector pin #7 (W/R) to a neutral (LBU). If 24VAC is not present on CB K2 connector pin #7 (W/R), check wiring connections from CT. If 24VAC is present on CB K2 connector pin #7 (W/R) and not on CB K2 connector pin #8 (W/BR), replace CB. If 24VAC is present on CB K2 connector pin #8 (W/BR), check for 24VAC at WV solenoid. If 24VAC is present, replace WV. If WV is energized and fill/refill exceeds 90sec. FT with no water in the reservoir, check for clogged WV screen or DV leaking. Note: If UFS remains open

90 seconds after LFS opens (WV energized), a 1beep alarm sounds (90 sec. FT). This alarm resets automatically once UFS closes. If reservoir is full and overflowing, check for open UFS. See "II.E. Float Switch Check and Cleaning." If WV deenergizes and water continues to fill the reservoir, replace WV.

14

Image 14
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 DiagnosisIce Production Check Service DiagnosisDiagnostic Procedure Page Page Page Page Control Board Check 5VDC CB K9 Connector Component Pin # Wire Color 5VDC CB K9 Connector See FigHigh-Pressure Switch HPS 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 Cleaning Float Switch Check and CleaningFloat Switch Check Page No Ice Production Possible Cause Startup Diagnostic TablesNo Ice Production 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 DrainPortion Dispense Mode SwitchContinuous IV. Removal and Replacement of Components Service for Refrigerant LinesEvacuation and Recharge R-404A Refrigerant RecoveryBrazing 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 and Agitating Motors Dispense ComponentsDispense Auger and Agitator Frequency Area Task MaintenanceMaintenance Schedule 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