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Hoshizaki Hoshizaki America, Inc. Modular Flaker Models FD-650MAH-C, MWH-C, MRH-C SERVICE MANUAL “A Superior Degree of Reliability” www.hoshizaki.com Number: 73199 Issued: 11-3-2014...
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Hoshizaki provides this manual primarily to assist qualified service technicians in the service of the appliance. Should the reader have any questions or concerns which have not been satisfactorily addressed, please call, send an e-mail message, or write to the Hoshizaki Technical Support Department for assistance. Phone: 1-800-233-1940; (770) 487-2331 Fax: 1-800-843-1056;...
IMPORTANT This manual should be read carefully before the appliance is service. Read the warnings and guidelines contained in this manual carefully as they provide essential information for the continued safe use, service, and maintenance of the appliance. Retain this manual for any further reference that may be necessary. CONTENTS Important Safety Information ....................
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VI. Preparing the Icemaker for Periods of Non-Use ............. 46 VII. Disposal ......................... 48 VIII. Technical Information ....................49 A. Specification and Performance Data ................49 1. FD-650MAH-C (air-cooled) ..................49 2. FD-650MWH-C (water-cooled) ................50 3. FD-650MRH-C (remote air-cooled) ................ 51 B. Wiring Diagrams ......................52...
Important Safety Information Throughout this manual, notices appear to bring your attention to situations which could result in death, serious injury, damage to the appliance, or damage to property. WARNING Indicates a hazardous situation which could result in death or serious injury.
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WARNING, continued • The appliance is not intended for use by persons (including children) with reduced physical, sensory, or mental capabilities, or lack of experience and knowledge, unless they have been given supervision or instruction concerning use of the appliance by a person responsible for their safety. •...
I. Construction and Water/Refrigeration Circuit Diagram A. Construction 1. Air-Cooled Models (MAH-C) Inlet Water Valve Control Box Spout Evaporator Thermostatic Expansion Air-Cooled Valve Condenser Drain Valve Fan Motor Gear Motor Ice Chute Drier Bin Control (Infrared Sensor) Compressor...
4. Ice Making Unit Cutter Extruding Head (Upper Bearing) Seal Bolt Auger Cylinder Insulation Mechanical Seal "O"-Ring Socket Head Cap Screw Hex Bolt Housing (Lower Bearing) Spline Coupling Gear Motor...
B. Water/Refrigeration Circuit Diagram 1. Air-Cooled Models (MAH-C) Spout Inlet Water Valve Water Supply Float Switch Water Level Evaporator Reservoir Thermostatic Overflow Hose Expansion Valve Gear Motor Drain Valve Drain Pan To Drain Drain Hose Drier Condenser Air-Cooled Fan Motor Condenser High-Pressure Switch Compressor...
2. Water-Cooled Models (MWH-C) Inlet Water Valve Spout Water Supply Float Switch Water Level Evaporator Reservoir Thermostatic Expansion Valve Overflow Hose Gear Motor Drain Valve Drain Pan To Drain Drain Hose Drier Cond. Water Inlet Water-Cooled Cond. Condenser Water Outlet High-Pressure Switch Water Regulating...
B. Service Diagnosis WARNING • The appliance should be diagnosed and repaired only by qualified service personnel to reduce the risk of death, electric shock, serious injury, or fire. • Risk of electric shock. Use extreme caution and exercise safe electrical practices. Power switch in "OFF"...
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Diagnosis DV: If DV does not energize, check for 24VAC at CB K2 #10 (W/BU) to neutral (LBU). If 24VAC is not present, check control switch continuity. If open while in the "DRAIN" position, replace control switch. If closed, check for 0VDC at CB K9 #1 (W/BK) to K9 #2 (W/BK).
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6) Freeze Cycle – "COMP" LED is on. 5-min. ice purge timer terminates or CB "SERVICE" button pressed. "COMP" LED is on. "GM" LED remains on. Comp energizes. GM, FM/FMR, and CDR continue. Ice production begins 4 to 6 minutes after Comp energizes depending on ambient and water conditions.
C. Control Board Check Before replacing a control board that does not show a visible defect and that you suspect is bad, always conduct the following check procedure. This procedure will help you verify your diagnosis. Before diagnosing the control board drain the reservoir. 1) Check CB S1 dip switch settings to assure that they are in the factory default position.
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3) CB 5VDC Output: Control Switch, High-Pressure Switch, Compressor Delay Relay, and Float Switch. When checking 5VDC voltage, always place the red positive test lead from the multimeter to CB K5 pin closest to CB K4 connector. See Fig. 1. Then place the black negative test lead from the multimeter to the corresponding pin to complete the 5VDC check.
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d. Float Switch: See Fig. 2. 5VDC is present at CB K5 pin closest to CB K4 connector to CB K8 #5 (BK). If 5VDC is not present, replace CB. When UFS and LFS are open, 5VDC is present at CB K8 #5 (BK) to K8 #6 (R) (UFS) and K8 #7 (DBU) (LFS). When UFS and LFS are closed, 0VDC is present at CB K8 #5 (BK) to K8 #6 (R) (UFS) and K8 #7 (DBU) (LFS).
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5) CB 24VAC Output: Inlet Water Valve and Drain Valve. a) Inlet Water Valve: When the control switch is in the "ICE" position, "WTRIN" LED turns on and inlet water valve energizes. If not, check for 24VAC at CB K2 #7 (W/R) to a neutral (LBU).
D. Bin Control Check 1. Bin Control Sensor Check (infrared) IMPORTANT Make sure CB S1 dip switch 7 is in the "ON" position. This allows the control board to monitor the bin control sensor. 1) Turn off the power supply. 2) Remove the front panel, top panel, and control box cover.
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8) CB "GM" and "COMP" LEDs are on. Use an object to cover BC sensor lens at the bottom of the icemaker. If the bottom of the icemaker is not accessible in your application, remove the thumbscrew securing BC housing, remove BC from the base, then cover BC sensor.
2) Remove FS assembly from the reservoir cover. See Fig. 8. 3) Wipe down FS assembly with a mixture of 1 part Hoshizaki "Scale Away" and 25 parts warm water. 4) While not necessary, the floats can be removed from the shaft during cleaning. If you remove them, note that the blue float is on top.
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7) Turn on the power supply, then move the power switch to the "ON" position to start teh automatic icemaking process. 8) Replace the front panel in its correct position. Legend: FS–float switch; LFS–lower float switch; UFS–upper float switch; Red (R) (upper float switch) Black (BK) (common)
F. Diagnostic Tables Before consulting the diagnostic charts, check for correct installation, proper voltage per appliance nameplate, and adequate water supply. Check control board using the steps in "II.C. Control Board Check." 1. No Ice Production No Ice Production - Possible Cause Startup 1.
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No Ice Production - Possible Cause Startup/Fill Cycle (reservoir full) (continued) 4. Fan Motor a) Open motor windings. b) Mechanical failure or fan blade binding. Freeze Cycle 1. Compressor Delay Relay a) Not energized. b) Defective. c) Control board defective. 2.
III. Controls and Adjustments • A Hoshizaki exclusive control board is employed in Hoshizaki icemakers. • All models are pretested and factory adjusted. • For a control board check procedure, see "II.C. Control Board Check." NOTICE • Fragile, handle very carefully.
B. LED Lights and Alarm Safeties The "POWER OK" LED indicates proper control voltage and will remain on unless a control voltage problem occurs. For further details, see "II.B. Service Diagnosis." Energized Sequence Step Components Min. Max. Fill Cycle WTRIN Ice Purge Cycle GM, FM/FMR 5 min.
Increasing the shutdown delay setting allows for a higher level of ice in the bin before the icemaker shuts down. For a typical dispenser unit application, a 100-second shutdown delay is recommended. When used with a standard Hoshizaki ice storage bin, any shutdown delay setting is acceptable. WARNING! Increasing the shutdown delay allows a higher level of ice in the dispenser unit/ice storage bin before shutdown.
3. Drain Frequency Control (S1 dip switch 4) This unit is factory set for optimum performance with the 1-in-1 drain cycle (S1 dip switch 4 in the "OFF" position). This setting allows for removal of sediment from the evaporator without interrupting the icemaking process. An optional 1-in-12 drain cycle is available.
D. Switches The power switch and the control switch are used to control the icemaker. They are located on the control box. 1. Power Switch The power switch has 2 positions: "OFF" and "ON." 2. Control Switch The control switch has 2 positions: "ICE" and "DRAIN."...
IV. Refrigeration Circuit and Component Service Information WARNING • This appliance should be diagnosed and repaired only by qualified service personnel to reduce the risk of death, electric shock, serious injury, or fire. • Move the power switch to the "OFF" position and turn off the power supply before servicing.
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For air-cooled and water-cooled models, see the nameplate for the required refrigerant charge. For remote models, see the rating label inside the icemaker. Hoshizaki recommends only virgin refrigerant or reclaimed refrigerant which meets ARI Standard 700 (latest edition) be used.
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6) A liquid charge is required when charging an R-404A system (to prevent fractionation). Place the service cylinder on the scales; if the service cylinder is not equipped with a dip tube, invert the service cylinder, then place it on the scales. Open the high-side valve on the gauge manifold.
B. Component Service Information NOTICE • When replacing a component listed below, see the notes to help ensure proper operation. • When replacing evaporator assembly and water circuit components, make sure there are no water leaks after the repair is complete. •...
1. Upper Bearing Wear Check To ensure that the bearing inside the extruding head does not exceed the wear tolerance of .02", follow the instructions below. See Fig. 11. 1) Turn off the power supply. 2) Remove the front and top panels. 3) Remove the strap connecting the spout to the chute assembly, then remove the spout.
3. Removal and Replacement of Auger 1) Remove the front and top panels. 2) Move the control switch to the "DRAIN" position and drain the water from the evaporator. After the water has drained, move the power switch to the "OFF" position, then turn off the power supply.
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7) Remove the insulation and the thermostatic expansion valve bulb on the suction line. 8) Disconnect the inlet and outlet tubing. 9) Remove the allen head cap screws securing the evaporator to the lower housing. 10) Lift off the evaporator. 11) Inspect the mechanical seal and O-ring prior to installing the new evaporator.
5. Removal and Replacement of Mechanical Seal and Lower Housing 5a. Mechanical Seal 1) Remove the front and top panels. 2) Move the control switch to the "DRAIN" position and drain the water from the evaporator. After the water has drained, move the power switch to the "OFF" position, then turn off the power supply.
6. Removal and Replacement of Gear Motor NOTICE! Hoshizaki recommends that the gear motor capacitor be replaced at the same time as the gear motor. 1) Remove the front and top panels. 2) Move the control switch to the "DRAIN" position and drain the water from the evaporator.
V. Maintenance The maintenance schedule below is a guideline. More frequent maintenance may be required depending on water quality, the appliance's environment, and local sanitation regulations. WARNING • Only qualified service technicians should service the appliance. • To reduce the risk of electric shock, do not touch the icemaker power switch or control switch with damp hands.
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Maintenance Schedule (continued) Every 6 Icemaker and Clean and sanitize per the cleaning and sanitizing instructions provided in Months Dispenser Unit/Ice the instruction manual or maintenance label on the icemaker. Storage Bin Evaporator Wipe down with a clean cloth and warm water. Slowly pour one cup of Condensate Drain sanitizing solution (prepare as outlined in the sanitizing instructions in this Pan and Gear...
VI. Preparing the Icemaker for Periods of Non-Use NOTICE When storing the icemaker for an extended time or in sub-freezing temperatures, follow the instructions below to prevent damage. When the icemaker is not used for two or three days under normal conditions, it is sufficient to only move the power switch to the "OFF"...
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3. On water-cooled models, remove the water from the water-cooled condenser: 1) Make sure the power supply is off, then remove the front, top, and right side panels. 2) Close the condenser water supply line shut-off valve. If connected to a closed loop system, also close the condenser return line shut-off valve.
VII. Disposal The appliance contains refrigerant and must be disposed of in accordance with applicable national, state, and local codes and regulations. Refrigerant must be recovered by properly certified service personnel.
We reserve the right to make changes in specifications and design without prior notice. A. Specification and Performance Data Pressure data is recorded at 5 min. into freezing cycle. The data not in bold should be used for reference only. 1. FD-650MAH-C (air-cooled) Specification Sheet AC SUPPLY VOLTAGE 115/60/1...
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