Service Manual Modular Crescent Cuber Models KM-1100MAJ50 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.
Startup Cycle Steps 8 Legend: BC–bin control CB–control board Comp–compressor FM–fan motor FS–float switch HGV–hot gas valve HPT–harvest pump time LLV–liquid line valve PM–pump motor WV–inlet water valve FS check Comp energized FM energized PM energized LLV energized HGV de-energized FS closed 5-min. minimum freeze timer in control Anti-Slush Thermistor temperature reaches 36°F (2.2°C) (5.8 kΩ). PM de-energized for 10 sec.
2. Shutdown Flow Chart Shutdown Flow Chart Shutdown and Restart BC Operation 1. Bin Full Within 10 sec. after ice contacts BC bulb, icemaker shuts down. Ice contacts BC bulb 2. Icemaker Off All components de-energized. 3. Ice Level Lowered No ice touching BC bulb. Icemaker starts at "1. 1-Minute Fill Cycle." To 1.
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. Sequence and Component Diagnosis 3) Power On: Turn on the power supply, then move the control switch to the "ICE" position. A 5‑sec. delay occurs. CB red "POWER OK" LED and CB green "BC CLOSED" LED turn on. If CB yellow "BC OPEN" LED is on (indicating a full bin), check CB K4 red jumper. Move ice away from BC bulb. 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.
4) 1-Min. Fill Cycle – LED 4 is on. WV and X11 relay energize. After 1 min., CB checks for a closed FS. If FS is closed, the harvest cycle begins. If harvest cycle begins (Comp, HGV, and FM energized), continue to step 5a. If FS is open, WV remains energized until FS closes (low water safety protection during initial start up and at the end of each harvest). Diagnosis: Check that water enters the water tank.
5b) Harvest Pump Timer – LEDs 1, 3, and 2 are on. 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). When WV de-energizes, LED 4 turns off, X11 relay de-energizes and LED 3 turns on. PM energizes. Comp, FM, HGV, and X10 relay continue. Diagnosis: Place a thermometer on the suction line next to the thermistor. Has it warmed to 48°F (9°C) or warmer? Confirm thermistor status. See "II.F.
a) Freeze Cycle Diagnosis: Confirm Comp, FM, and PM continue. Confirm that FM and LLV energize. Confirm WRV opens. Next, confirm HGV and X10 relay deenergize. During the first 5 min. of freeze, confirm evaporator is cooling. If not, confirm WV de-energized (not leaking by), HGV de-energized (not bypassing), LLV and FM energize, TXV and HM operate correctly, WRV opens, Comp is efficient, and refrigerant charge is correct. See "VIII.A. Specification and Performance Data Sheets.
g) Freeze Termination Diagnosis: After 5 min. in freeze, disconnect CB K5 FS connector. 15 sec. later appliance should switch out of the freeze cycle (15 second delay after FS opens before terminating the freeze cycle). If appliance remains in freeze longer than 15 sec. after FS removed, replace CB. If appliance switches with FS removed but would previously not switch out of freeze with FS connected (long freeze - 3 beep alarm), see "II.E. Float Switch Check and Cleaning.
Pump-Out Diagnosis: In the freeze cycle before pump-out (see table above), after 5 min. of freeze disconnect CB black K5 connector (FS connector). Check that PM stops and re-starts. Next, check that PM rotation is correct (water flowing down the drain through CV). If PM does not stop and re-start, check that CB LEDs 1, 3, and 2 are on. If not, replace CB. If LEDs 1, 3, and 2 are on and PM does not energize, check for 115VAC at CB K1 #5 (DBU) to neutral (W). If 115VAC is not present, 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 BC shuts down the icemaker within 10 sec. when ice contacts the thermostatic bulb, regardless of the cycle at activation. NOTICE When the ambient temperature is below 45°F (7°C), BC opens and shuts down the appliance even if the ice storage bin is empty. When BC is set in the prohibited range, the appliance operates continuously even if the ice storage bin is filled with ice. Setting in the prohibited range may result in severe damage to the appliance.
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. Cube Guide 1. Float Switch Check To check FS, follow the steps below. Rubber Cap 1) Turn off the power supply.
13) Check for continuity across FS leads. With the water tank full, FS should be closed. If FS is closed and the icemaker will not switch from the 1-min. fill cycle to the initial harvest cycle, replace CB. If FS is open, confirm that the water tank is full. If the water tank is not full, check the water supply, water filters, and inlet water valve. If the water tank is full, follow the steps in "II.E.2. Float Switch Cleaning." After cleaning FS, check it again. Replace if necessary.
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. 3) Remove the control box cover. 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) Disconnect the thermistor connector from CB K3 connector and check the resistance between thermistor leads. Normal range is 4.7 to 6.2 kΩ.
H. 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. Main Transformer a) Voltage tap switch not set to proper voltage. (208-230/60/1 Models with main b) Coil winding open or shorted. transformer and all 208-230/60/3 Models) 3. Fuse (Control Box) a) Blown. 4. Thermostatic Bin Control See "II.D. Bin Control Check" a) Tripped with bin filled with ice. b) Ambient temperature too cool.
No Ice Production - Possible Cause 15. Pump Motor a) Motor winding open. b) Bearing worn out or locked rotor. c) Defective capacitor. d) Mechanical seal worn out. 16. Thermostatic Expansion Valve a) Bulb loose. b) Operating erratically. 17. Liquid Line Valve a) Closed in freeze cycle. b) Open in harvest cycle. 18. Fan Motor a) Motor winding open. b) Bearing worn out or locked rotor. c) Defective capacitor. 19. Water System a) Water leaks causing short freeze time. 2.
Freeze-Up - Possible Cause 13. Thermostatic Bin Control See "II.D. Bin Control Check" a) Defective. Freeze Cycle 1. Evaporator a) Scaled up. b) Damaged. 2. Spray Tubes and/or Spray Guides a) Dirty. b) Out of position. 3. Refrigerant Charge a) Low. 4. Control Board See "II.C. Control Board Check" a) Freeze timer (S4 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.
3. Low Ice Production Low Ice Production - Possible Cause Long Harvest Cycle 1. Evaporator a) Scaled up. 2. Spray Tubes and/or Spray Guides a) Dirty. b) Out of position. 3. Refrigerant Charge a) Low. 4. Water Supply a) Low water pressure. b) External water filters clogged. c) Insufficient water line size. Minimum 1/4" Nominal ID (6 mm Nominal OD in the EU) water tubing or equivalent. d) Too cold. 5. Control Board See "II.C. Control Board Check" a) Thermistor connection loose (K3). 6.
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____________Freeze-Up 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 1.
B. LED Lights and Audible Alarm Safeties Beep occurs and red "POWER OK" LED turns on when control switch is moved to "ICE" position. Sequence Green LEDs 1 through 4 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 1, 4, 3, 2. 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: S4 Dip Switch No. KM-1100MAJ50 1 2 3 4 5 6 7 8 9 10 OFF OFF OFF OFF OFF OFF ON OFF OFF OFF S5 Dip Switch (Do Not Adjust) "J" Control Board Dip Switch No.
2. Harvest Timer (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. The first pump-out is dependent on S4 dip switch 5. See the table below.
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. When the pump motor is energized (S4 dip switch 7 on), water circulates over the evaporator.
8. Freeze Timer (S4 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.
11. Minimum Harvest Time (S5 dip switch 4) NOTICE Factory set for proper operation. Do not adjust. Adjustment outside the factory default setting may result in damage to the appliance. S5 Dip Switch Setting No. 4 Minimum Harvest Timer OFF 120 sec. ON 70 sec. 12. Anti-Slush (S5 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.
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. 3 phase: Install a new magnetic contactor. 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.
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 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.
2. Remove the water from the water tank: 1) Turn off the power supply, then remove the front panel. 2) Move the control switch to the "OFF" position. 3) Drain the water tank. Remove the rubber cap covering the overflow pipe in the water tank. Remove the overflow pipe by turning it counterclockwise. After the water tank has drained, replace the overflow pipe and the rubber cap in their correct positions.
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-1100MAJ50 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.) FOR THE EUROPEAN MARKET ICE CAPACITY lbs.
* 45 412±22 0 PSIG 328±22 PSIG Cut-out Cut-in Air Models * High-Pressure Switch B. Wiring Diagram 1.
