Hoshizaki KM-1300MAH, KM-1300MWH, KM-1300MRH Removal and Replacement of Expansion Valve

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5. REMOVAL AND REPLACEMENT OF EXPANSION VALVE

IMPORTANT

Sometimes moisture in the refrigerant circuit exceeds the Drier capacity and freezes up at the Expansion Valve. 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)Turn off the power.

2)Remove the panels.

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

4)Remove the insulation and the Expansion Valve Bulb on the suction line.

5)Remove the Expansion Valve Cover, and disconnect the Expansion Valve using brazing equipment.

6)Braze the new Expansion Valve, with nitrogen gas flowing at the pressure of 3 - 4 PSIG.

WARNING

Always protect the valve body by using a damp cloth to prevent the valve from overheating. Do not braze with the valve body exceeding 250°F.

7)Install the new Drier.

8)Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.

9)Evacuate the system, and charge it with refrigerant. For air-cooled and water- cooled models, see the Nameplate for the required refrigerant charge. For remote air-cooled models, see the Charge Label in the machine compartment.

10)Attach the Bulb to the suction line in position. Be sure to secure it with clamps and to insulate it.

11)Place the new set of Expansion Valve Covers in position.

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Contents KM-1300MAH KM-1300MWH KM-1300MRH Hoshizaki AMERICA, INC Contents Maintenance Specifications KM-1300MAH Air-cooled2a. KM-1300MWH Water-cooled 2b. KM-1300MWH Water-cooled Serial No. M10156D KM-1300MRH Remote air-cooled Condensing Unit URC-12F Specifications Model URC-12F II. General Information Construction KM-1300MWH Water-cooled KM-1300MRH Remote air-cooled SOLID-STATE Control Features of Control Products E Controller BoardController Board Controller BoardPage Harvest Cycle Beep every 3 sec. = High Evaporator Temperature 127 FMinute Fill Cycle Freeze CycleControl Products HOS-001A Board Sequence 1st Cycle 2nd Cycle and after with pump drain 2nd Cycle and after with no pump drain Controls and Adjustments Setting Time Setting Frequency Checking the Controller Board Page III. Technical Information KM-1300MWH Water-cooled KM-1300MRH Remote air-cooled Wiring Diagrams KM-1300MAH Air-cooled and KM-1300MWH Water-cooledCut-out 412 ±21.3 Psig Cut-in 327±21.3 Psig Timing Chart Page Performance Data Serial # L00001F to M10155C KM-1300MWH Water-cooled Serial # M10156D KM-1300MRH Remote air-cooled IV. Service Diagnosis No ICE Production Problem Possible Cause RemedyController Board Problem Possible Cause Remedy Evaporator is Frozen UP LOW ICE ProductionAbnormal ICE OthersRefrigerant Recovery Service for Refrigerant LinesEvacuation and Recharge R-404A Brazing Removal and Replacement of Compressor Important Removal and Replacement of Drier Removal and Replacement of Expansion Valve Removal and Replacement of HOT GAS Valve and Line Valve Removal and Replacement of Evaporator Important Page Page Page Removal and Replacement of Thermistor Important Removal and Replacement of FAN Motor Removal and Replacement of Water Valve Removal and Replacement of Pump MotorRemoval and Replacement of Spray Tubes VI. Maintenance and Cleaning Instructions Preparing the Icemaker for Long StoragePage Cleaning Cleaning Procedure Sanitizing Procedure Following Cleaning Procedure Page Maintenance