Service Manual Self-Contained Crescent Cuber Models KM-81BAJ KM-116BAJ KM-161BAJ, BWJ 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.................................................................................................. 5 I.
IV. Refrigeration Circuit and Component Service Information.............................................. 43 A. Refrigeration Circuit Service Information..................................................................... 43 B. Component Service Information................................................................................... 46 C. Water Regulating Valve Adjustment (water-cooled model)........................................... 46 V. Maintenance.................................................
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 • Do not make any alterations to the appliance. Alterations could result in electric shock, injury, fire, or damage to the appliance. • 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 this appliance.
I. Construction and Water/Refrigeration Circuit Diagram A. Construction 1.
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B. Water/Refrigeration Circuit Diagram 1.
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Comp energized HGV energized WV energized DV de-energized FS closed Thermistor in control FS check 5-min. min. freeze timer FS opens or Comp energized freeze timer HGV energized terminates DV energized PM de-energizes for 2 sec., then restarts for 10/20 sec. FM de-energized FS in control • Factory set for every 10th cycle (S1 dip switch 5 & 6) • Pump motor stops for 2 sec., then restarts for 10/20 sec. (S1 dip switch 3 & 4) 4.
BC Operation 14 Legend: BC–bin control DV–drain valve FS–float switch 2 sec. after all components de-energize, DV energizes for a max. of 5 min. or until the FS opens. 2. Water Tank Drain To 1. 1-Minute Fill Cycle Icemaker starts at "1. 1-Minute Fill Cycle." 4. Ice Level Lowered BC closed (BC actuator paddle disengaged) Red "POWER OK" LED on solid Minimum off time: 90-sec. minimum 90-sec. off timer terrminates before the appliance can restart. 3.
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. • Before servicing the appliance, move the control switch to the "OFF" position and unplug the appliance.
1. Sequence and Component Diagnosis 3) Power On: Plug the appliance into the electrical outlet. Move the control switch to the "ICE" position. A 5‑sec. delay occurs. CB red "POWER OK" LED turns on. Note: • CB red "POWER OK" LED remains on unless the 10.5VAC power supply is interrupted (K2 connector). • Check CB using the steps in "II.C. Control Board Check." • Confirm CB red "POWER OK" LED is on. If CB red "POWER OK" LED is flashing (indicating a full bin), check BC. Move ice away from BC actuator paddle.
5a) Initial Harvest Cycle – LEDs 5, 6, and 8 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 (S1 dip switch 1 & 2 and S2 dip switch 4). WV is energized during harvest for a maximum of 6 min. or the length of harvest minus HPT setting (S1 dip switch 7 & 8), whichever is shorter.
6) Freeze Cycle – LED 5 and 7 is on. Comp and PM continue. FM energizes. HGV de‑energizes. Appliance is held in freeze by a temperature/time short cycle protection cycle. Thermistor reaches 36°F (2°C), then the 5-min. short cycle protection timer starts. After the 5-min. short cycle protection timer terminates and FS opens, freeze cycle terminates. Slush Control: When slush control is enabled (S2 dip switch 6 "ON"), PM de-energizes when thermistor reaches 50°F (10°C) (3.9kΩ) for 10 sec.
g) WRV (KM-161B_J) Diagnosis: WRV is factory set and generally no adjustment is required. If WRV fails to open in freeze, check for proper refrigerant pressures. See "VIII.A. Specification and Performance Data Sheets." If refrigerant pressures are correct and WRV does not open, adjust or replace as needed. See "IV.C. Water Regulating Valve Adjustment (water‑cooled models)." h) Freeze Termination Diagnosis: After thermistor has reached 36°F (2°C) and the 5 min.
Pump-Out Diagnosis: In the freeze cycle before pump-out (see table above), after thermistor reaches 36°F (2°C) and the 5 min. short cycle protection timer has terminated, disconnect the FS connector. Check that CB LEDs 4, 5, 6, and 7 are on, PM stops, then restarts, DV energizes, and water is flowing down the drain through DV. If not, continue to steps below. a) CB Diagnosis: Confirm FM de-energizes. If FM is energized with LEDs 4, 5, 6, and 7 on, replace CB.
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. WARNING! Risk of electric shock. Care should be taken not to touch live terminals. Once reset, the icemaker starts at the 1-minute fill cycle. For audible alarm information, see "III.B.
D. Bin Control Check 1. Bin Control Check This appliance uses a mechanical bin control to control the ice level in the storage bin. No adjustment is required. To check BC, follow the steps below. 1) Remove the louver, move the control switch to the "OFF" position, then unplug the icemaker from the electrical outlet. 2) Clear any ice away from BC. 3) Remove the control box, then disconnect CB K1 connector from CB. 4) Check for continuity across BC leads.
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) Remove the louver, move the control switch to the "OFF" position, then unplug the icemaker from the electrical outlet. 2) Clear any ice away from BC.
5) Remove the actuator paddle from the switch mount. 6) Wipe down the switch mount and actuator paddle with 1 part of Hoshizaki "Scale Away" and 25 Parts warm water. Rinse the switch mount and actuator paddle thoroughly with clean water. See Fig. 3. Proximity Switch Actuator Paddle Bin Control Assembly Fig. 3 7) Replace the actuator paddle back on the switch mount. 8) Replace and secure the bin control assembly back in its correct position.
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. 1. Float Switch Check To check FS, follow the steps below. 1) Remove the louver, move the control switch to the "OFF" position, then unplug the icemaker from the electrical outlet.
2. Float Switch Cleaning Depending on local water conditions, scale may build up on FS. Scale on the switch can cause the float to stick. In this case, FS should be cleaned. 1) Remove the louver, move the control switch to the "OFF" position, then unplug the icemaker from the electrical outlet. 2) Disconnect the silicone hose to drain the water, then after all the water has drained reconnect the silicone hose back in its correct position. See Fig. 4. 3) Remove the top and upper rear panels.
F. Thermistor Check To check thermistor resistance, follow the steps below. 1) Unplug the icemaker from the electrical outlet. 2) Remove the louver, then move the control switch to the "OFF" position. 3) Remove the top panel. 4) Remove the thermistor from the refrigerant tubing. 5) Immerse the thermistor sensor portion in a glass containing ice and water for 2 or 3 min. 6) From the compressor area, locate the thermistor/CB connector protective plastic bundle.
H. Diagnostic Tables 1. No Ice Production No Ice Production - Possible Cause 1. Power Supply a) Off, blown fuse, or tripped breaker. b) Unplugged or loose connection. c) Not within specifications. 2. Fuse (Control Box) a) Blown. 3. Control Switch a) In "OFF" or "SERVICE" position. b) Bad contacts. 4. High-Pressure Switch (KM-161 B_J Models) a) Dirty condenser. b) Fan motor not operating. c) Refrigerant overcharged. d) Bad contacts. e) Refrigerant lines or components plugged. f) HGV defective. 5.
No Ice Production - Possible Cause 15. Thermostatic Expansion Valve (KM-161 B_J Models) a) Bulb loose. 16. Fan Motor a) Motor winding open. b) Operating erratically. b) Bearing worn out or locked rotor. c) Defective capacitor. 17. Water System a) Water leaks causing short freeze time. 2. Freeze-Up Defrost and clean the icemaker prior to diagnosing freeze-up. Fill out a freeze-up checklist. See "II.I.
Freeze-Up - Possible Cause Freeze Cycle 1. Evaporator a) Scaled up. b) Damaged. 2. Spray Tubes and/or Spray Guides a) Dirty. 3. Refrigerant Charge a) Low. 4. Control Board See "II.C. Control Board Check" a) Freeze timer (S1 dip switch 9 & 10) set incorrectly. 5. Inlet Water Valve a) Leaking by. 6. Float Switch See "II.E. Float Switch Check and Cleaning" a) Float does not move freely. 7. Pump Motor a) RPM too slow. b) Out of position. b) Defective. b) Defective. b) Impeller damaged. 8.
Low Ice Production - Possible Cause Long Freeze Cycle 1. Evaporator a) Scaled up, dirty. 2. Float Switch See "II.E. Float Switch Check and Cleaning" a) Scaled up, dirty. 3. Inlet Water Valve a) Leaking by. 4. Hot Gas Valve a) Erratic or open. 5. Condenser a) Clogged. 6. Control Board See "II.C. Control Board Check" a) Float switch connection loose (K5). b) Float sticking. c) Defective switch. b) Defective. 7. Refrigerant Charge a) Low. 8.
I. 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. • 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.
A. Control Board Layout Control Board • Relay LEDs (6) (indicate which relays are energized as listed below) • K7 Connector Transformer • LED 5 (X1 Relay) Compressor (Comp) Fan Motor-Remote (FMR) • LED 6 (X2 Relay) Hot Gas Valve (HGV) Fan Motor (FM) (FM off when LED on) • K3 Connector Power Relay • "POWER OK" LED (Lights when power is supplied to the board. Flashes when bin control is activated.
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 4 through 8 turn on and sequence from initial startup as listed in the table below. Order of green LEDs from the outer edge of control board is 5, 6, 8, 9, 4, 7. Sequence Step LED Energized Components Time LEDs are On Min. Max.
C. Settings and Adjustments 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: S1 Dip Switch No.
2. Harvest Time (S1 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 (S1 dip switch 5 & 6) 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. The first pump-out is dependent on S1 dip switch 5 & 6. See the table below.
6. Freeze Timer (S1 dip switch 9 & 10) NOTICE Adjust to proper specification, or the icemaker may not operate correctly. The freeze timer setting determines the maximum allowed freeze time to prevent possible freeze-up issues. Upon termination of the freeze timer, the control board initiates the harvest cycle or pump-out cycle. After 2 consecutive freeze timer terminations, the control board shuts down the icemaker. In this case, see "II.H.3. Low Ice Production" for possible solutions.
9. Minimum Harvest Time (S2 dip switch 3) NOTICE Factory set for proper operation. Do not adjust. Adjustment outside the factory default setting may result in damage to the appliance. Do not adjust. This must be left in the factory default position or the unit will not operate properly. The KM-81BAJ, KM-116BAJ, and KM-161BAJ/BWJ do not refill. 10. Harvest Completion Detection Control (S2 dip switch 4) NOTICE Factory set for proper operation. Do not adjust.
11. Overfreeze Detection Control (S2 dip switch 5) NOTICE Factory set for proper operation. Do not adjust. Adjustment outside the factory default setting may result in damage to the appliance. Do not adjust. This must be left in the factory default position or the unit will not operate properly. It is deactivated on the KM-81BAJ, KM-116BAJ, and KM-161BAJ/BWJ.
12. Slush Control (S2 dip switch 6) NOTICE Factory set for proper operation. Do not adjust. Adjustment outside the factory default setting may result in damage to the appliance. This dip switch setting provides slush control during the freeze cycle. Disabled (OFF): When the evaporator temperature reaches 41°F (5°C) the control board reads a 4.8 kΩ signal from the thermistor and de-energizes the water pump for 10 sec., then energizes the water pump for the duration of freeze time.
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 rating label inside the icemaker. 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).
B. Component Service Information NOTICE When replacing a component listed below, see the notes to help ensure proper operation. Component Compressor Notes 1 phase: Install a new start capacitor, run capacitor, and start relay. Thermostatic • Attach the thermostatic expansion valve bulb to the suction line in the same location as Expansion Valves the previous bulb. • The bulb should be between the 10 and 2 o'clock positions on the tube. • Secure the bulb with the clamp and holder, then insulate it.
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 plug with damp hands • Before servicing: Move the control switch to the "OFF" position and unplug the power supply cord from the electrical outlet.
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" 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.
3. On water-cooled model, remove the water from the water-cooled condenser: 1) Make sure the appliance is unplugged and the control switch is in the "OFF" position. 2) Remove the rear cover. 3) 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. 4) Open the condenser water supply line drain valve. If connected to a closed loop system, also open the condenser return line drain 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.
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. 1. KM-81BAJ Specification Sheet AC SUPPLY VOLTAGE AMPERAGE MINIMUM CIRCUIT AMPACITY MAXIMUM FUSE SIZE ELECTRIC & WATER CONSUMPTION ELECTRIC W (kWH/100 lbs.) WATER gal./24HR (gal./100 lbs.
2. KM-116BAJ Specification Data AC SUPPLY VOLTAGE AMPERAGE MINIMUM CIRCUIT AMPACITY MAXIMUM FUSE SIZE ELECTRIC & WATER CONSUMPTION ELECTRIC W (kWH/100 lbs.) WATER gal./24HR (gal./100 lbs.) ICE PRODUCTION PER CYCLE APPROXIMATE STORAGE CAPACITY BIN CONTROL SYSTEM REFRIGERANT CHARGE 115/60/1 5.5 A (5 Min. Freeze AT 104°F / WT 80°F) 15 A 15 A 90/70°F 70/50°F 340 (8.10) 330 (6.44) 20 (20.0) 25 (19.9) 2.2 lbs. (1 kg) 110pcs. 53 LBS. Mechanical Bin Control R134a, 0 lb. 7.8 oz.
3. KM-161BAJ Specification Data AC SUPPLY VOLTAGE AMPERAGE MINIMUM CIRCUIT AMPACITY MAXIMUM FUSE SIZE ELECTRIC & WATER CONSUMPTION ELECTRIC W (kWH/100 lbs.) WATER gal./24HR (gal./100 lbs.) ICE PRODUCTION PER CYCLE APPROXIMATE STORAGE CAPACITY BIN CONTROL SYSTEM REFRIGERANT CHARGE 115/60/1 7.1 A (5 Min. Freeze AT 104°F / WT 80°F) 15 A 15 A 90/70°F 70/50°F 440 (8.60) 440 (6.47) 28 (23.0) 49 (30.1) 2.6 lbs. (1.2 kg) 130pcs. 78 LBS. Mechanical Bin Control R134a, 0 lb. 7.4 oz.
4. KM-161BWJ Specification Sheet AC SUPPLY VOLTAGE AMPERAGE MINIMUM CIRCUIT AMPACITY MAXIMUM FUSE SIZE ELECTRIC & WATER CONSUMPTION ELECTRIC W (kWH/100 lbs.) WATER gal./24HR (gal./100 lbs.) WATER COOLED CONDENSER gal./24HR (gal./100 lbs.) ICE PRODUCTION PER CYCLE APPROXIMATE STORAGE CAPACITY BIN CONTROL SYSTEM REFRIGERANT CHARGE 115/60/1 6.4 A (5 Min. Freeze AT 104°F / WT 80°F) 15 A 15 A 90/70°F 70/50°F 330 (6.23) 360 (5.61) 31 (24.2) 53 (35.0) 0 (0) 0 (0) 2.5 lbs. (1.1 kg) 130pcs. 78 LBS.
OFF OFF ON OFF OFF KM-116BAJ KM-161BAJ KM-161BWJ ON ON ON OFF OFF OFF KM-81BAJ KM-116BAJ KM-161BAJ KM-161BWJ 2 OFF OFF OFF OFF START CAP. 100MFD 189-227MFD MODEL KM-116BAJ KM-161BWJ 3 OFF OFF OFF OFF COMPRESSOR CAPACITOR TABLE 1 OFF SWITCH No.