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WARNING Only qualified service technicians should install and service the icemaker. To obtain the name and phone number of your local Hoshizaki Certified Service Representative, visit www.hoshizaki-europe.com. No service should be undertaken until the technician has thoroughly read this Service Manual. Failure to service and...
IMPORTANT This manual should be read carefully before the appliance is serviced. 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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VIII. Technical Information ....................45 A. Specification and Performance Data Sheets ............... 45 1. KM-520MAJ-E ......................45 2. KM-660MAJ-E ....................... 46 B. Wiring Diagrams ......................47 1. KM-520MAJ-E, KM-660MAJ-E ................47...
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 • Children should be properly supervised around this appliance. • Do not climb, stand, or hang on the appliance or allow children or animals to do so. Serious injury could occur or the appliance could be damaged. • Do not use combustible spray or place volatile or flammable substances near the appliance.
I. Construction and Water/Refrigeration Circuit Diagram A. Construction 1. Air-Cooled Models (MAJ-E) Drain Valve Water Supply Inlet Cleaning Valve Spray Tubes Stainer Hot Gas Valve Evaporator Condenser High-Pressure Inlet Water Valve Switch Thermostatic Expansion Valve Fan Motor Liquid Line Valve Float Switch Drier Compressor...
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. Control switch in "OFF" position does not de-energize all loads Use extreme caution and exercise safe electrical practices.
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1. Sequence and Component Diagnosis 3) Power On: Plug the power supply cord back into the electrical outlet, then move the control switch to the "ON" position and the mode switch to the "ICE" position. A 5-sec. delay occurs. CB red "POWER OK" LED turns on. If CB yellow "BC OPEN"...
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5a) Initial Harvest Cycle – LEDs 1, 4, and 2 are on. WV continues. Comp and HGV energize. CB monitors the warming of the evaporator via the thermistor located on the suction line. When the thermistor reaches 48°F (9°C), CB reads 3.9 kΩ from the thermistor and turns harvest termination over to the harvest timer (S4 dip switch 1 &...
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5c) Initial Harvest Cycle Termination Diagnosis: When the thermistor reaches 48°F (9°C), CB reads 3.9 kΩ from the thermistor and turns harvest termination over to the harvest timer (S4 dip switch 1 & 2 and S5 dip switch 4). Check discharge line temperature.
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e) FM and LLV Diagnosis: If FM or LLV does not energize, check for 115VAC at CB K1 #3 (BK) to neutral (W). If 115VAC is not present and LED 2 is on, check for 115VAC at CB K1 #1 (V). If 115VAC is present at #1 (V) and not at #3 (BK), replace CB.
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7) Pump-Out Cycle – LEDs 1, 3, and 5 are on (10/20 second pump-out). Timing of the first pump-out is determined by S4 dip switch 5. See the table below. Control Board Settings S4 Dip Switch Setting Pump-Out Frequency Control Board No.
C. Control Board Check Before replacing CB 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. Alarm Reset: If CB is in alarm (beeping), press the "ALARM RESET" button on CB while CB is beeping.
1. Bin Control Check The bin control is factory set for use on Hoshizaki America standard ice storage bins. If mounted on a dispenser application or if a change to the ice level in an ice storage bin application is desired, see "II.D.2.
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4) As water begins to fill the water tank (1-min. fill), place an object 5" to 7" (127 to 178 mm) away from the bin control lens. See Fig. 3. 15 sec. later, the icemaker shuts down. Remove the object from the bin control lens. 30 sec. later, the icemaker restarts. Bin Control Lens Fig.
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• Failure to properly adjust the bin control setting could result in water leakage, ice backup, and icemaker damage. The bin control is factory set to 1 for use on Hoshizaki America standard ice storage bins. See the table below for adjustments to ice level.
E. Float Switch Check and Cleaning FS is used to determine that there is sufficient water in the water tank after the 1-min. fill cycle and after each harvest cycle. FS is also used to determine that the appropriate volume of water has been converted into ice before switching out of the freeze cycle. No adjustment is required.
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6) Wipe down the float switch bracket assembly, stem, and float with a mixture of 1 part Hoshizaki "Scale Away" and 25 parts warm water. Rinse the parts thoroughly with clean water. WARNING! Do not remove the lock nut on the float switch assembly. This is factory sealed and must not be removed.
F. Thermistor Check To check thermistor resistance, follow the steps below. 1) Turn off the power supply. 2) Remove the front panel. Move the control switch to the "OFF" position, then remove the top and right side panels. 3) Remove the thermistor from the refrigerant tubing. 4) Immerse the thermistor sensor portion in a glass containing ice and water for 2 or 3 min.
I. Diagnostic Tables 1. No Ice Production No Ice Production - Possible Cause 1. Power Supply a) Off, blown fuse, or tripped breaker. b) Not within specifications. 2. Fuse (Control Box or Power a) Blown. Supply Cord) 3. Control Switch a) In "OFF"...
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2. Freeze-Up Defrost and clean the icemaker prior to diagnosing freeze-up. Fill out a freeze-up checklist. See "II.J. Freeze Up Check List," the Hoshizaki America Technician's Pocket Guide, or contact your local distributor for a copy of the freeze-up checklist.
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Freeze-Up - Possible Cause 10. Thermistor a) Loose, disconnected, or defective. See "II.F. Thermistor Check" 11. Thermostatic Expansion Valve a) Defective. 12. Hot Gas Valve a) Defective. 13. Liquid Line Valve a) Defective. Freeze Cycle 1. Evaporator a) Scaled up. b) Damaged.
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Low Ice Production - Possible Cause 9. Compressor a) Inefficient or off. 10. Liquid Line Valve a) Erratic or open. 11. Thermostatic Expansion Valve a) Defective. Long Freeze Cycle 1. Evaporator a) Scaled up, dirty. 2. Float Switch a) Scaled up, dirty. See "II.E.
J. Freeze-Up Check List Freeze-Up Check List Please Complete When Diagnosing a Freeze-Up, Refrigerant Leak, or Low Charge Technical Support Fax #: 770-487-3360 Make Copies And Use As Needed Model #___________________________ Serial # _________________________Install Date______________Fail Date___________ List model and manufacture of bin or dispenser__________________________. Date appliance was last cleaned:__________.
III. Controls and Adjustments • A Hoshizaki exclusive control board is employed in KM series appliances. • All models are pretested and factory adjusted. • For a control board check procedure, see "II.C. Control Board Check." NOTICE • Fragile, handle very carefully.
A. Control Board Layout 1. "K" Control Board "K" Control Board • "ALARM RESET" • "OUTPUT TEST" Button • S4 Dip Switch Button (used to test relays on control board) • K3 (white) Connector • Bin Control Switch Thermistor Open LED (yellow) (harvest control and high temperature safety) •...
B. LED Lights and Audible Alarm Safeties Beep occurs and red CB "POWER OK" LED turns on when control switch is moved to "ICE" position. Sequence Green LEDs 1 through 5 turn on and sequence from initial startup as listed in the table below.
NOTICE Dip switches are factory set. Failure to maintain factory settings may adversely affect performance and warranty coverage. For more information, contact your Hoshizaki Service Center. 1. Default Dip Switch Settings The dip switches are factory-adjusted to the following positions: S4 Dip Switch No.
2. Harvest Time (S4 dip switch 1 & 2) The harvest timer starts counting when the thermistor reaches 48°F (9°C) at the evaporator outlet and the control board reads 3.9 kΩ from the thermistor. The harvest timer is factory set, and generally no adjustment is required. However, a setting longer than the factory setting may be advised in cases where the drain provided at harvest needs to be prolonged for extra cleaning.
4. Pump-Out Frequency Control (S4 dip switch 5) The pump-out frequency control is factory set to drain the water tank every 10 cycles. Generally no adjustment is required. However, where water quality is bad and the icemaker needs a pump-out more often, the pump-out frequency can be adjusted. The pump-out frequency control can be set to have a pump-out occur every cycle, or every 10 cycles.
6. Harvest Pump Time (Harvest Assist) (S4 dip switch 7) NOTICE Factory set for proper operation. Do not adjust. Adjustment outside of the factory default setting may result in damage to the appliance. a) Harvest Pump Time (Harvest Assist) Depending on S4 dip switch 7 setting, the pump motor either stays off or is energized during the last seconds of the harvest cycle.
In this case, see "II.I.3. Low Ice Production" for possible solutions. The freeze timer is factory set and no adjustment is required. Before changing this setting, contact Hoshizaki Technical Support at 1-800-233-1940 for recommendations.
10. Refill Counter (S5 dip switch 2 and 3) NOTICE Do not adjust. These must be left in the factory default position or the icemaker will not operate correctly. S5 Dip Switch Setting Refill Counter No. 2 No. 3 1 refill 9 refills 10 refills 11.
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 control switch to the "OFF" position and turn off the power supply. Place the disconnect in the "OFF"...
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2. Brazing WARNING • R-404A itself is not flammable at atmospheric pressure and temperatures up to 176°F (80°C). • R-404A itself is not explosive or poisonous. However, when exposed to high temperatures (open flames), R-404A can be decomposed to form hydrofluoric acid and carbonyl fluoride both of which are hazardous.
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Remember to loosen the connection and purge the air from the hose. For the required refrigerant charge, see the rating label inside the icemaker. Hoshizaki recommends only virgin refrigerant or reclaimed refrigerant which meets ARI Standard 700 (latest edition) be used.
• The thermistor should be at the 12 o'clock position on the tube. • Smoothly fill the recessed area of the thermistor holder with high thermal conductive type sealant. Hoshizaki America part number 4A0683-01 (Silicone Heat Sink Compound 10-8108 manufactured by GC Electronics), KE-4560 RTV (manufactured by ShinEtsu Silicones), or equivalent are recommended.
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 control switch or service switch with damp hands •...
VI. Preparing the Appliance for Periods of Non-Use NOTICE • When storing the appliance for an extended time or in sub-freezing temperatures, follow the instructions below to prevent damage. • To prevent damage to the water pump, do not operate the appliance with the control switch in the "WASH"...
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.
VIII. Technical Information We reserve the right to make changes in specifications and design without prior notice. A. Specification and Performance Data Sheets Pressure data is recorded at 5 min. into freezing cycle. The data not in bold should be used for reference only.
2. KM-660MAJ-E Specification Sheet AC SUPPLY VOLTAGE 230/1/50 AMPERAGE 8.4 A (5 Min. Freeze AT 104°F/WT 80°F) MINIMUM CIRCUIT AMPACITY 15 A MAXIMUM FUSE SIZE 15 A ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F ELECTRIC W (kWH/100 lbs.) 1170 (4.85) 1080 (4.18) WATER gal./24HR (gal./100 lbs.)
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