Hoshizaki dcm-75ibah service manual

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9)Ice Purge Cycle"GM" LED is on. UFS closes (WV de-energizes) and "WTRIN" LED turns off. 5sec. GM delay timer and 30-min. FZT start. 5-sec. GM delay timer terminates. GM and GMPR energize. 5min. IPT starts. GM runs for 5 min. to clear any ice from the evaporator. Diagnosis: If "GM" LED is off, check that UFS closed.

If UFS is closed and "GM" LED does not turn on, replace CB. If "GM" LED is on and GM is off, confirm 115VAC at CB K1 connector pin #2 (BR) to neutral (W). Check for 115VAC at CB K1 connector pin #3 (DBU) to a neutral (W). If no voltage is present at CB K1 connector pin #2 (BR), check wiring connections. If no voltage is present at CB K1 connector pin #3 (DBU), replace CB. If 115VAC is present, check 115VAC 3A GM fuse, GM internal protector, GM windings, capacitor, and GM coupling between auger and GM. If GM internal protector is open, allow to cool and reset. If reset does not occur, replace GM. If Comp energizes at the same time GM energizes, check CB. See "II.C. Control Board Check."

10)Freeze Cycle"COMP" and "GM" LEDs are on. 5 min. IPT terminates. GM continues. CB confirms GM operation through GMPR terminal #3 (W/O) and terminal #5 (W/O). Comp and FM energize. Ice production begins 4 to 6 min. after Comp and FM energize depending on ambient and water temperature conditions. Diagnosis: 5 min. after GM energizes, confirm Comp LED turns on and Comp and FM energize. If not, check that GMPR is energized (115VAC). Next, check continuity between GMPR terminal #3 (W/O) and terminal #5 (W/O). If open, GMPR is deenergized or defective. If closed, and "COMP" LED is not on, replace CB. If "COMP" LED turns on and Comp and FM do not energize, confirm 115VAC at CB Comp X1 relay (BR) to a neutral (W). If 115VAC is not present, check connections. If 115VAC is present, confirm 115VAC at CB Comp X1 relay (R) to a neutral (W). If 115VAC is not present and "COMP" LED is on, replace CB. If 115VAC is present, check Comp external protector (overload), allow to cool and reset. If reset does not occur, replace external protector. Check Comp start and run capacitors, Comp start relay, and Comp windings. If FM does not energize, check FM run capacitor, that the fan blade is not binding, and that FM windings are good.

11)Refill/Low Water Safety"COMP," "GM," and "WTRIN" are on. As ice is produced, the water level in the reservoir drops. UFS opens. Nothing happens at this time. When LFS opens, 90-sec. FT starts. WV energizes. Comp, FM, and GM continue. As water fills the reservoir, LFS closes. Nothing happens at this time. When UFS closes, WV deenergizes, 90-sec. FT terminates, and 30-min. FZT resets. This continues until BC shuts down the appliance or power is turned off to the appliance. Diagnosis: Confirm that the water level has dropped and UFS and LFS are open. See "II.E. Float Switch Check and Cleaning." Check for dirty or sticking float switches, clogged WV screen, defective WV coil, or DV leaking by. 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. Comp and FM deenergize. GM deenergizes 90 sec. later. WV and alarm continue until UFS closes.

Note: Each time UF/S closes, 30-minute FZT starts. 30-minute FZT resets when UF/S closes again. If UF/S does not close again within 30 minutes, CB shuts down the appliance and sounds a 5-beep alarm every 5 seconds. See "III.B. LED Lights and Audible Alarm Safeties."

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Contents DCM-751BAH-OS DCM-751BWH-OS Hoshizaki AMERICA, INC Contents Page Important Safety Information Page DCM-751BAH-OS Construction and Water/Refrigeration Circuit DiagramsDCM-751BWH-OS Ice Making Unit Water/Refrigeration Circuit Diagrams Spout Inlet Water Valve Water Supply Float Diagnosis Control Board Sequence Flow Chart DCM-751BH-OSChart OperationService 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 Bin Control BC 5VDC CB K8 Connector See Fig5VDC CB K8 Connector Component Pin # Wire Color Gear Motor Protect Relay Gmpr5VDC 0VDC Portion Signal #5 R Red K4 pin closest 5VDC Power Supply #3 W/BK Connector Pin # Wire Color Neutral LBU Open Closed 24VAC CB K2 ConnectorBin Control Check Float Switch Check and Cleaning Float Switch CheckFloat Switch Cleaning Page Diagnostic Tables No Ice ProductionNo Ice Production Possible Cause Startup Shutdown No Ice Production Possible CauseWater Dispense-Push Button Ice/Water DispensingIce Dispense-Push Button Ice Dispense-Opti-ServeIII. Controls and Adjustments DCM-751BH Control Board LayoutDCM-751BH-OS K2 Connector Drain Valve #10 W/BUEnergized Components Min Max LED Lights and Audible Alarm SafetiesNo. of Beeps Type of Alarm Reset Options Every 5 sec Icemaking Sequence Sequence StepDrain Frequency Control S1 dip switch Settings and AdjustmentsDefault Dip Switch Settings Infrared Sensor Shutdown Delay S1 dip switch 1, 2Factory Use S1 Dip Switch 9 Continuous Dispensing Timer S1 dip switch 5Bin Control Selector S1 dip switch Bin Control Shutdown Delay S1 dip switchDrain Power Switch, Control Switch, and Dispense Mode SwitchICE OFFDispense Mode Switch ContinuousPortion Service for Refrigerant Lines IV. Removal and Replacement of ComponentsRefrigerant Recovery BrazingEvacuation and Recharge R-404A Evaporator Assembly Components. See Fig Important Notes for Component ReplacementEvaporator Assembly Upper Bearing Wear Check Icemaking UnitRemoval and Replacement of Auger Removal and Replacement of Extruding HeadRemoval 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 DCM-751BAH VIII. Technical Information Specification SheetsDesign without prior Potable Water WATER-COOLED Condenser DCM-751BWH779 758 Reference without *marks 738 719 ICE Production Performance Data800 363 Wiring Diagrams DCM-751BH-OS