Service Manual Stackable Square Cuber Models IM-500SAB hoshizakiamerica.
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.
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 • 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. They might catch fire. • Keep the area around the appliance clean. Dirt, dust, or insects in the appliance could cause harm to individuals or damage to the appliance.
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 Operation Flow Chart Cycle Steps 1. 30-Sec. 2. Harvest Cycle 3. Freeze Cycle Startup • Max. freeze time: 45 min. (CB Setting 6) • HGV: If CBTh≤81°F (27°C) (CB Setting 74), Cycle HGV repeatedly energizes 40 sec./ de-energizes 40 sec. • FM: If CBTh≥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. 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. • Moving parts (e.g., fan blade) can crush and cut. Keep hands clear.
1. Operation Diagnosis 1) Startup Cycle: Turn on the power supply. Move the control switch to the "ICE" position. "on" appears on CB display. HGV energizes and Comp/AMD 30-sec. delay timer starts. Note: • CB display "on" LED remains on unless the 10.5VAC power supply to CB CN1 is interrupted. • Check CB using the steps in "II.C.Control Board Check." • Confirm BC is CLOSED. If BC is open, remove ice from BC. If no ice is around BC and icemaker does not start, see "II.D. Bin Control Check.
2) Harvest Cycle: Comp 30-sec. delay timer terminates, 20-sec. WV delay timer starts, Comp and AMD (opening) energize. HGV continues. 20-sec. WV delay timer terminates, WV energizes. 30 sec. WV on timer starts. AMD de-energizes when AMPS activates at water tank fully open position. Once ET reaches 41°F (5°C), HGV de-energizes, FM and AMU (closing) energize. 30-sec. WV on timer terminates, WV de-energizes. AMU de-energizes when AMPS activates at water tank fully closed position. WV energizes. 144-sec.
3) Freeze Cycle: AMPS activated (water tank completely closed). 60-sec. PM delay timer starts (initial startup; 60-sec. PM delay timer, normal operation; 30-sec. PM delay timer). WV energizes and 144-sec. WV on timer starts (initial startup; 144-sec. WV on timer, normal operation 52-sec. WV on timer). Comp and FM continue. Evaporator cooling. Once PM delay timer terminates, PM energizes. 44 sec. (or 22 sec.) later WV on timer terminates, WV de-energizes.
Freeze Termination: CB monitors time after ET temperature ≤ 32°F (0°C). CB terminates freeze cycle when the following equation is satisfied: temp. (absolute value) × time (min.) = (absolute value of CB Setting 2) × (CB Setting 3) Using default settings, freeze cycle is terminated when: temp. (absolute value) × time (min.) = 185 This formula helps maintain consistent dimple size regardless of differences in seasonal ambient and water temperatures. ET temperature is recorded 30 seconds after PM energizes.
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. Always choose a white (W) neutral wire to establish a good neutral connection when checking voltages. Error Codes: If CB is in error (E1, E2, EE(3-9), EE(EA), EE(EC), EE(Ed)), see "III.F. Error Codes." 1) Move CS to the "ICE" position.
D. Bin Control Check 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 BC, 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.
G. Diagnosis Table First see "III.F. 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. b) Bad contacts. 4. High-Pressure Switch a) Dirty condenser or air filter. 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. Control Board a) Thermistor connection loose (K3). b) Defective. 3. Evaporator (Cube Control) a) Loose, disconnected, or defective. Thermistor See "II.E. Evaporator Thermistor Check" 4. Hot Gas Valve a) Erratic or closed. 5. Compressor a) Inefficient or off. 6. Thermostatic Expansion Valve a) Defective. 7. Refrigerant Charge a) Low. Long Freeze Cycle 1. Evaporator a) Scaled up, dirty. 2.
Large-Hole Cubes - Possible Cause (Also see III.G.1. Dimple Diameter") 1. Condenser a) Dirty condenser or air filter. 2. Fan Motor a) Defective. 3. Refrigerant Charge a) Low. Large-Hole Cubes - Possible Cause (Also see III.G.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.G.2. Ice Clarity." 2.
H. Freeze-Up Check List Freeze-Up Check List IM Series 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____________Freeze-Up Date___________ List model and manufacture of bin or dispenser__________________________. Date appliance was last cleaned:__________.
III. Controls and Adjustments A. 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. It is especially important to touch the metal part of the icemaker when handling or replacing the control board.
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 Compressor Start DC Relay Drive Output • CN9 Connector Display Output • CN4 Connector Data Input/Output • RESET Button • CN1 Connector Control Transformer (10.
B. Control Board 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.C. 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).
C. 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 IM-500SAB Default Compressor 37 Compressor Output Selection DO NOT ADJUST 0: X8 (DC Relay) On 1: X1 (AC Relay) On 1 Anti-Slush Control 0 to 90 sec. 0=ignore, no anti-slush (1 sec. increments) 0 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.
Control Board (CB) Setting Menu Category No. Item IM-500SAB Default Range Water Tank 74 Water Tank Ice Control Lower Temperature 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.
E. 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.
2. Checking or Changing the Control Board Model Code 1) With 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 "h6" is displayed. 3) Press the "RESET" button to view the current model code. To change the model code, continue through the remaining steps; otherwise, the display returns to normal if no buttons are touched for 20 sec.
Error Codes Error Problem Code Corrective Action/Reset Details EE (E3) Water Tank Opening Backup Timer Check actuator motor and control board. 3-minute opening backup timer starts when water tank starts to open. Press the "RESET" button to reset. If actuator motor's internal position sensor does not indicate water tank is fully open within 3 minutes, display shows "EE" and unit stops for 60 minutes. If error recurs after unit resumes operation, display shows "EE" and unit shuts down.
G. Quick Adjustments 1. Dimple Diameter The factory set dimple diameter is 3/16" (5 mm). NOTICE! Do not decrease the dimple diameter below 3/16" (5 mm). a) To increase dimple diameter: 1) Remove front panel. 2) Press the "SERVICE 1" button to view the current freeze cycle termination temperature setting. 3) Press the "SERVICE 1" button to raise freeze cycle termination temperature setting (Control Board Setting 2). Temperature setting rises in .5°C increments. The ".
2. Ice Clarity In hard water conditions, white ice may be produced. In such cases, install a water filter and/or water softener, then follow the instructions below. 1) Move the control switch to the "OFF" position, then turn off the power supply. 2) Remove the front panel. 3) Remove the screw, then move the water tank drain pipe to the drain position. See Fig. 2. Use the screw to secure the water tank drain pipe in the drain position.
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).
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 and Performance Data Sheets 1. IM-500SAB Specification Sheet AC SUPPLY VOLTAGE 115/60/1 AMPERAGE 11.5 A (5 Min. Freeze AT 104°F / WT 80°F) MINIMUM CIRCUIT AMPACITY 20 A MAXIMUM FUSE SIZE 20 A ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F ELECTRIC W (kWH/100 lbs.) 1000 (5.80) 830 (4.05) WATER gal./24HR (gal./100 lbs.) 95 (23.0) 117 (24.
B. Wiring Diagram 1.
