Hoshizaki DCM-750BAH-OS, DCM-750BWH-OS service manual

Page 58

G. Removal and Replacement of Water Regulating Valve

WaterCooled 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.

1)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.

2)Remove the apron panel, then remove the left side panel.

3)Recover the refrigerant and store it in an approved container.

4)Disconnect the drip tray hose from the tee. Remove the four screws securing the drip tray, then remove the drip tray and hose.

5)Close the condenser water supply line shut-off valve, then open the condenser water supply line drain valve.

6)Attach a compressed air or carbon dioxide supply to the condenser water supply line drain valve.

7)Open the water regulating valve by using a screwdriver to pry up on the spring retainer underneath the spring. While holding the valve open, blow out the condenser using the compressed air or carbon dioxide supply until water stops coming out.

8)Disconnect the capillary tube at the condenser outlet.

9)Disconnect the flare-connections of the valve.

10)Remove the screws and the valve from the bracket.

11)Install the new valve.

12)Remove the drier, then place the new drier in position.

13)Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG.

14)Use an electronic leak detector or soap bubbles to check for leaks. Add a trace of refrigerant to the system (if using an electronic leak detector), and then raise the pressure using nitrogen gas (140 PSIG). DO NOT use R-404A as a mixture with pressurized air for leak testing.

15)Evacuate the system, and charge it with refrigerant. See the nameplate for the required refrigerant charge.

16)Connect the flare-connections.

17)Close the condenser water supply line drain valve, then open the condenser water supply line shut-off valve.

18)Check for water leaks.

19)Replace the drip tray and drip tray hose in their correct positions. Secure the hose to the tee. Pour water into the drip tray and check for leaks.

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Contents DCM-750BAH DCM-750BAH-OS DCM-750BWH DCM-750BWH-OS Hoshizaki AMERICA, INC Contents Page Specifications Icemaker DCM-750BAHDCM-750BAH-OS Water TEMP. FDCM-750BWH Potable Water WATER-COOLED CondenserDCM-750BWH-OS Potable Water Water Cooled CondenserII. General Information Construction DCM-750BWH-OS Ice Making Unit Sequence of Operation Startup Control Board Control Board Layout DCM-750BAH, DCM-750BWH Control BoardDCM-750BAH-OS, DCM-750BWH-OS Features LED LightsPower Supply Controls and Adjustments Portion ControlControl Board Check Procedure Ice Making ComponentsDispensing Components DCM-750BAH, DCM-750BWH Float Switch Inlet Water Valve DCM-750BWH-OS Wiring Diagrams Wire Color CodeDCM-750BAH-OS, DCM-750BWH-OS Sequence of Electrical Circuit Ice Making DCM-750BWH-OSIce Purge Cycle Orange WHITE/BLACK Pink WHITE/BROWN RED WHITE/BLUE Violet Hour Drain Cycle / Drain Switch Shutdown Low Water Safety High Pressure Switch Sequence of Electrical Circuit Dispensing Continuous DispensePortion Dispense Performance Data 192Approximate IV. Service Diagnosis Diagnostic Procedure Ice Production Check Diagnostic Charts No Ice ProductionProblem Possible Cause Remedy Problem Possible Cause Remedy Low Ice Production Other Dispensing Opti Serve OS Sensors 5b. Ice Dispensing Portion Mode 5a. Ice Dispensing Continuous Mode5c. Water Dispensing Refrigerant Recovery Removal and Replacement of ComponentsService for Refrigerant Lines BrazingEvacuation and Recharge R-404A Removal and Replacement of Compressor Removal and Replacement of Expansion Valve Removal and Replacement of Evaporator Assembly Components Removal and Replacement of Extruding Head Upper Bearing Wear CheckRemoval and Replacement of Auger Removal and Replacement of EvaporatorPage 5b. Lower Housing Removal and Replacement of Gear Motor Page Removal and Replacement of Water-Cooled Condenser Page Adjustment of Water Regulating Valve Water-Cooled Model Only Removal and Replacement of Fan MotorRemoval and Replacement of Inlet or Dispensing Water Valve Removal and Replacement of Drain ValveDispensing Auger and Agitator Removal and Replacement of Dispensing SystemDispensing or Agitating Motor Page VI. Cleaning and Maintenance Cleaning and Sanitizing InstructionsCleaning Solution Water SystemSanitizing Solution Dispensing ComponentsBin Control Bracket Snap Pin Maintenance Frequency Area TaskPreparing the Icemaker for Long Storage