Hoshizaki DKM-500BAH Removal and Replacement of Components, Service for Refrigerant Lines

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V. Removal and Replacement of Components

IMPORTANT

Ensure all components, fasteners and thumbscrews are securely in place after the equipment is serviced.

IMPORTANT

1.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 parts.

2.Always install a new filter drier every time the sealed refrigeration system is opened.

3.Do not leave the system open for longer than 15 minutes when replacing or servicing parts.

A.Service for Refrigerant Lines

1. Refrigerant Recovery

The icemaker unit is provided with two refrigerant access valves–one on the low-side and one on the high-side line. Using proper refrigerant practices recover the refrigerant from the access valves and store it in an approved container. Do not discharge the refrigerant into the atmosphere.

2.Evacuation and Recharge (R-404A)

1)Attach charging hoses, a service manifold and a vacuum pump to the system. Be sure to connect charging hoses to both high and low-side access valves.

IMPORTANT

The vacuum level and vacuum pump may be the same as those for current refrigerants. However, the rubber hose and gauge manifold to be used for evacuation and refrigerant charge should be exclusively for POE oils.

2)Turn on the vacuum pump. Never allow the oil in the vacuum pump to flow backward.

3)Allow the vacuum pump to pull down to a 29.9" Hg vacuum. Evacuating period depends on pump capacity.

4)Close the low-side valve and high-side valve on the service manifold.

5)Disconnect the vacuum pump, and attach a refrigerant service cylinder to the high- side line. Remember to loosen the connection, and purge the air from the hose. See the nameplate for the required refrigerant charge. Hoshizaki recommends only virgin refrigerant or reclaimed refrigerant which meets ARI Standard No. 700-88 be used.

6)A liquid charge is recommended for charging an R-404A system. Invert the service cylinder. Open the high-side, service manifold valve.

7)Allow the system to charge with liquid until the pressures balance.

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Image 32 Contents
DKM-500BAH Hoshizaki AMERICA, INC Contents Page Specifications DKM-500BAHII. General Information Construction DKM-500BAHSequence of Operation DKM-500BAH Sequence Flow Chart and Component Operation CycleControl Board Control Board Control Products E Control BoardControl Board Layout Harvest Backup Timer and Freeze Timer High Temperature SafetyLow Water Safety Maximum Water Supply Period 6 minutesLED Lights and Audible Alarm Safeties PM, SR, DVHarvest Control Thermistor Controls and AdjustmentsDefault Dip Switch Settings Harvest Timer dip switch 1 Pump-Out Timer dip switch 3Bin Control Pump-Out Frequency Control dip switch 5Freeze Timer dip switch 9 Bin Control Troubleshooting Control Board Check ProcedureMachine Will Not Start Machine Will Not Shut OffSwitches Control Board ReplacementControl Switch Service SwitchCirculate WashDKM-500BAH Wiring Diagram Timing Chart Page Performance Data 110IV. Service Diagnosis Minute Diagnostic Procedure No Ice Production Diagnostic ChartsIce Making Problem Possible Cause Remedy Problem Possible Cause Remedy Evaporator is Frozen Up Low Ice Production Abnormal IceOther DispensingProblem Possible Cause Remedy Removal and Replacement of Components Service for Refrigerant LinesRefrigerant Recovery Evacuation and Recharge R-404ARemoval and Replacement of Compressor BrazingRemoval and Replacement of Drier Removal and Replacement of Expansion Valve Removal and Replacement of Hot Gas ValveRemoval and Replacement of Evaporator Removal and Replacement of Condenser Removal and Replacement of Thermistor Removal and Replacement of Fan MotorRemoval and Replacement of Inlet Water Valve Removal and Replacement of Pump MotorRemoval and Replacement of Spray Tubes Removal and Replacement of Gear MotorRemoval and Replacement of Dispense Switch Removal and Replacement of SolenoidCleaning Procedure Icemaker VI. Cleaning and Maintenance InstructionsCleaning Instructions Sanitizing Procedure Icemaker Cleaning Procedure Bin Sanitizing Procedure BinMaintenance Instructions Preparing the Icemaker for Long StorageExterior Panels Air Filters