Hoshizaki Hoshizaki America, Inc. Stackable Square Cuber Model IM-500SAA “A Superior Degree of Reliability” SERVICE MANUAL www.hoshizaki.
WARNING Only qualified service technicians should install and service the appliance. To obtain the name and phone number of your local Hoshizaki Certified Service Representative, visit www.hoshizaki.com. No service should be undertaken until the technician has thoroughly read this Service Manual. Failure to service and maintain the appliance in accordance with this manual will adversely affect safety, performance, component life, and warranty coverage and may result in costly water damage.
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 ................................................................................................. 4 I.
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. NOTICE Indicates a situation which could result in damage to the appliance or property. IMPORTANT Indicates important information about the use and care of the appliance.
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. • Children should be properly supervised around the appliance. • Do not climb, stand, or hang on the appliance or allow children or animals to do so.
I. Construction and Water/Refrigeration Circuit Diagram A. Construction 1.
B. Water/Refrigeration Circuit Diagram 1.
II. Sequence of Operation and Service Diagnosis A. Sequence of Operation Flow Chart "IM" Control Board 1. 30-Sec. 2. Harvest Cycle 3. Freeze Cycle Startup • Max. freeze time: 45 min. (CB Setting 6) • HGV: If CBT≤81°F (27°C) (CB Setting Cycle 74), HGV repeatedly energizes 40 sec./ de-energizes 40 sec. • FM: If CBT≥118°F (48°C) (CB Setting 34), FM operates continuously in harvest cycle ET≤-1.3°F (-18.5°C) • Max. harvest time: 30 min.
B. Sequence of Operation 1. Startup Cycle When power supply is turned on, "on" appears on CB display and HGV energizes. 30 sec. later, harvest cycle starts. • If the "RESET" button is pressed during 30-sec. startup cycle time, startup cycle ends immediately and harvest cycle starts. 2. Harvest Cycle HGV continues. Comp and AMD energize. WV energizes as listed in table below. Initial Harvest CB after Power On Setting All WT WV Delay NA 20 sec. WV Time after 10, 11 95 sec. WV Delay WV Time NA 10 sec.
ET temperature is recorded 30 seconds after PM energizes. Water temperature correction value (CB Setting 13) is added to ET temperature and this is used as WT value in following harvest cycle. If CBT>81°F (27°C) (CB Setting 74) and CBT≤111°F (44°C) (CB Setting 70), when ET≤-1.3°F (-18.5°C) (CB Setting 2), HGV energizes 5 sec., de-energizes 25 sec., energizes 5 sec. (CB Settings 71 and 72) to reduce bonding of the water tank to the evaporator. CB monitors time after ET temperature≤32°F (0°C).
C. Service Diagnosis Table First see "III.G. Error Codes." If there are no recorded errors, refer to the table below. No Ice Production - Possible Cause 1. Power Supply a) Off, blown fuse, or tripped breaker. b) Not within specifications. 2. Fuse (Control Box) a) Blown. 3. Control Switch a) In "OFF" or "WASH" position. 4. High-Pressure Switch a) Dirty condenser or air filter. b) Bad contacts. b) Fan motor not operating. c) Refrigerant overcharged. d) Bad contacts.
Low Ice Production - Possible Cause Long Harvest Cycle 1. Evaporator a) Scaled up. 2. Refrigerant Charge a) Low. 3. Control Board a) Thermistor connection loose (K3). b) Defective. 4. Evaporator (Cube Control) a) Loose, disconnected, or defective. Thermistor See "II.E. Evaporator Thermistor Check" 5. Hot Gas Valve a) Erratic or closed. 6. Compressor a) Inefficient or off. 7. Thermostatic Expansion Valve a) Defective. Long Freeze Cycle 1. Evaporator a) Scaled up, dirty. 2.
Large-Hole Cubes - Possible Cause (Also see III.H.1. Dimple Diameter") 4. Icemaker Location a) Insufficient clearance. b) Ambient temperature too high. 5. Water Supply a) Water leaks. b) Improper water pressure. Cloudy Cubes - Possible Cause 1. Water Quality a) High hardness. See "III.H.2. Ice Clarity." 2. Slush Ice a) Use Anti-Slush Control (Control Board Settings 50 and 51).
D. Bin Control Check and Cleaning 1. Bin Control Check This appliance uses a lever-actuated proximity switch to control the ice level in the storage bin. No adjustment is required. To check, follow the steps below. 1) Turn off the power supply. 2) Remove the front panel, then move the control switch to the "OFF" position. 3) Remove the control box cover. Clear any ice away from BC. 4) Check BC wire harness connections. 5) Disconnect BC wire harness connector from CB CN11 connector.
2. Bin Control Cleaning Scale may build up on BC. Scale can cause the actuator paddle and magnet to stick. In this case, BC should be cleaned. WARNING CHOKING HAZARD: Ensure all components, fasteners, and thumbscrews are securely in place after the icemaker is serviced. Make sure that none have fallen into the dispense unit/ice storage bin. 1) Turn off the power supply. 2) Remove the front panel, then move the control switch to the "OFF" position. 3) Clear any ice away from BC.
E. Evaporator 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. 3) Remove the control box cover. 4) Remove the thermistor from the evaporator. 5) Immerse the thermistor sensor portion in a glass containing ice and water for 2 or 3 min. 6) Disconnect the thermistor connector from CB CN13 connector and check the resistance between thermistor leads. Normal range is 4.7 to 6.2 kΩ.
III. Controls and Adjustments A. Control Switch The control switch has three positions: OFF for power off, ICE for icemaking, and WASH to energize the water pump when cleaning and sanitizing. B. Control Board • A Hoshizaki exclusive control board is employed in IM series appliances. • All models are pretested and factory adjusted. NOTICE • Fragile, handle very carefully. • The control board contains integrated circuits, which are susceptible to failure due to static discharge.
1. Control Board Layout • CN16 Connector Actuator Motor Position Sensor (Hall IC) Input • CN11 Connector Bin Control Input • CN13 Connector Evaporator (Cube Control) Thermistor Input • CN10 Connector • CN9 Connector Compressor Start DC Relay Drive Output Display Output • CN4 Connector Data Input/Output • RESET Button • CN1 Connector Control Transformer (10.5VAC) Input • SERVICE 1 Button • SERVICE 2 Button • CN2 Connector 115VAC Input • F1 Fuse 6.
C. Control Buttons The control board features RESET, SERVICE 1, and SERVICE 2 Buttons 1. RESET Button • Press briefly to go to initial harvest cycle. • Press and hold for 3 seconds to enter control board setting mode. For details about control board settings, see "III.D. Control Board Setting Mode and Control Board Settings." 2. SERVICE 1 and SERVICE 2 Buttons • Press the "SERVICE 1" or "SERVICE 2" button briefly to display the current freeze cycle termination temperature (Control Board Setting 2).
D. Control Board Settings NOTICE Failure to maintain factory settings may adversely affect performance and warranty coverage. For more information, contact your Hoshizaki Service Center. 1) With "on" in display, press and hold the "RESET" button for 3 seconds. Display changes to "1". 2) Use the "SERVICE 1" and "SERVICE 2" buttons to choose a control board setting. 3) Press the "RESET" button to view the setting’s value. Current value flashes in display.
Control Board (CB) Setting Menu Category No. Item Range Water Supply, continued 12 Freeze Cycle Water Supply Time 1: Partial Drain (CB 0 to 90 sec. Setting 14) (1 sec. increments) Freeze Cycle Water Supply Time 1: Full Drain (CB Setting 14) 13 Water Temperature Correction Value Value added to correct the difference between the temperature at the evaporator (cube control) thermistor and actual water supply temperature.
Control Board (CB) Setting Menu Category No. Item Range Compressor 37 Compressor Output Selection DO NOT ADJUST Anti-Slush Control Hard Water Control Water Tank Ice Control 50 Pump De-Energized Time When temperature at evaporator (cube control) thermistor drops to 37°F (3°C) in the freeze cycle, pump de-energizes for the length of time set. Ice Bridge Control 0: X8 (DC Relay) On 1: X1 (AC Relay) On 1 0 to 90 sec. 0=ignore, no anti-slush (1 sec. increments) 0 0 to 5 sec.
Control Board (CB) Setting Menu Category No. Item IM-500SAA Default Range Water Tank 74 Water Tank Ice Control Lower Temperature 0 to 40°C Ice Control See CB Setting 70, 71, 72, 74 description above.
Control Board Information Display No. Item Description History Cleared by Pressing and Holding SERVICE 1 and SERVICE 2 Buttons Simultaneously for 5 Sec. when Item Value is Displayed? h1 Last Completed Freeze Cycle Time 0 to 99 min. Freeze cycles interrupted by bin control shutdown or the "RESET" button are not recorded. Yes h2 Number of Completed Freeze Cycles Since Last Counter Reset Counter updates every 10 freeze cycles.
F. Control Board Model Code Setting 1. Control Board Replacement 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" position. Lockout/Tagout to prevent the power supply from being turned back on inadvertently.
5) Press the "SERVICE 1" button to increase the first digit in the display and the "SERVICE 2" button to increase the second digit. Digits appear in the following order: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F. When a valid model code is displayed, the dot in the bottom right of the display turns on. For IM-500SAA, set model code to "08". 6) When the desired model code is displayed, press the "RESET" button to save the setting. "on" appears in the display.
G. Error Codes When the control board detects an error, the display shows one of the following error codes in the display mode. Error codes other than E1 and E2 are displayed as "EE" at the time of occurrence. To see the actual error code, see the error log. 1. With the unit on, press and hold the "SERVICE 1" button for 3 seconds. Display changes to "n1". 2. Use the "SERVICE 1" and "SERVICE 2" buttons to move through the list until "h4" is displayed. 3. Press the "RESET" button to view the error log.
Error Codes Error Problem Code EE (E5) Corrective Action/Reset Details High Evaporator Temperature Check for harvest problem (stuck HGV or control If evaporator temperature 140°F (60°C) or higher board relay), hot water entering unit, or shorted for 5 sec., unit stops. thermistor. Press the "RESET" button to reset. EE (E9) Condenser Thermistor Error If condenser thermistor is open or shorted for 2 sec., unit stops.
3) Press the "SERVICE 2" button to lower freeze cycle termination temperature setting (Control Board Setting 2). Temperature setting lowers in .5°C increments. The "." in the lower, right corner of the display indicates .5°C. Default is -18.5°C. NOTICE! Do not decrease dimple size below 3/16" (5 mm). 4) Once the display returns to "on" (20 seconds), the new setting is saved. 2. Ice Clarity In hard water conditions, white ice may be produced.
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" position. Lockout/Tagout to prevent the power supply from being turned back on inadvertently.
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. • Do not use silver alloy or copper alloy containing arsenic. 1) Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG.
5) Disconnect the gauge manifold hose from the vacuum pump and attach it to a refrigerant service cylinder. Remember to loosen the connection and purge the air from the hose. For the required refrigerant charge, see the nameplate. Hoshizaki recommends only virgin refrigerant or reclaimed refrigerant which meets ARI Standard 700 (latest edition) be used. 6) A liquid charge is required when charging an R-404A system (to prevent fractionation).
Water Pan Assembly Refer to illustration for assembly. Icemaking Assembly and Cam Mechanism Refer to illustration for assembly. 1. Water Tank 2. Water Plate Bracket 3. Bracket 4. Spring Hook Screw 5. Pump Tubing (Suction) 6. Pump Tubing (Discharge) 7. Pump Motor Bracket 8. Water Plate 9. Overflow Pipe 10. Screw (for Overflow Pipe) 11. Nylon Tie 12. O-ring J. Pump Motor Assembly S1-4. Tapping Screw S5. Machine Screw 33 G. Water Pan Assembly 1. Evaporator 2. Bolt 3. Collar (Spacer) 4. Bearing 5.
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 • Before servicing: Move the control switch to the "OFF" position and turn off the power supply.
VI. Preparing the Icemaker 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" position when the water tank is empty. When the appliance is not used for two or three days under normal conditions, it is sufficient to move the control switch to the "OFF" position.
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 Data 1. IM-500SAA AC SUPPLY VOLTAGE AMPERAGE MINIMUM CIRCUIT AMPACITY MAXIMUM FUSE SIZE APPROXIMATE ICE PRODUCTION PER 24 HR. lbs./day ( kg/day ) Reference without *marks SHAPE OF ICE ICE PRODUCTION PER CYCLE APPROXIMATE STORAGE CAPACITY ELECTRIC & WATER CONSUMPTION ELECTRIC W (kWH/100 lbs.) WATER gal./24HR (gal./100 lbs.
B. Performance Data Pressure data is recorded at 5 min. into freezing cycle. The data not in bold should be used for reference only. 1. IM-500SAA APPROXIMATE ICE PRODUCTION PER 24 HR. lbs./day kg./day APPROXIMATE ELECTRIC CONSUMPTION WATER TEMP. (ºF/ºC) AMBIENT TEMP.
C. Wiring Diagram 1.
