Hoshizaki KM-900MAF manual

SER VICE MANUAL NO.: ISSUED: REVISED: MAR. 19, 1999 73083 HOSHIZAKI MODULAR CRESCENT CUBER MODELS KM-900MAF KM-900MWF KM-900MRF KM-900MRF3 DEC. 15, 2003[...]

2 IMPORT ANT Only qualified service technicians should attempt to service or maintain this icemaker. No service or maintenance should be undertaken until the technician has thoroughly read this Service Manual. HOSHIZAKI AMERICA, INC. 618 Highway 74 South Peachtree City , GA 30269 Attn: HOSHIZAKI T echnical Support Department Phone: 1-800-233-1940 T[...]

3 Please review this manual. It should be read carefully before the icemaker is serviced or maintenance operations are performed. Only qualified service technicians should service and maintain the icemaker. This manual should be made available to the technician prior to service or maintenance. CONTENTS PAGE I. SPECIFICATIONS .......................[...]

4 IV. SERVICE DIAGNOSIS ........................................................................................... 40 1. NO ICE PRODUCTION ........................................................................................ 40 2. EVAPORATOR IS FROZEN UP .......................................................................... 43 3. LOW ICE PR[...]

5 I. SPECIFICATIONS 1. KM-900MAF * We reserve the right to make changes in specifications and design without prior notice.[...]

6 2. KM-900MWF * We reserve the right to make changes in specifications and design without prior notice.[...]

7 3. KM-900MRF * We reserve the right to make changes in specifications and design without prior notice.[...]

8 4. KM-900MRF3 * We reserve the right to make changes in specifications and design without prior notice.[...]

9 5. CONDENSING UNIT URC-12F[...]

10 SPECIFICATIONS MODEL: URC-12F EXTERIOR DIMENSIONS (W x D x H) REFRIGERANT CHARGE URC-12F WEIGHT CONNECTIONS REFRIGERANT ELECTRICAL CONDENSER HEAD PRESSURE CONTROL AMBIENT CONDITION Galvanized Steel 35 - 11/16” x 15-11/16” x 21-15/16” (907.2 x 398 x 557.8 mm) R404A 4 lbs. 7 oz. (2000 g) Net 80 lbs. (36 kg) Shipping 87 lbs. (39 kg) One Shot [...]

11 II. GENERAL INFORMA TION 1. CONSTRUCTION [a] KM-900MAF[...]

12 [b] KM-900MWF[...]

13 [c] KM-900MRF[...]

14 [d] KM-900MRF3[...]

15 2. CONTROLLER BOARD [a] SOLID-STATE CONTROL 1) A HOSHIZAKI exclusive solid-state control is employed in KM-900MAF, KM-900MWF, KM-900MRF and KM-900MRF3 Modular Crescent Cubers. 2) A Printed Circuit Board (hereafter called “Controller Board”) includes a stable and high quality control system. 3) All models are pretested and factory-adjusted. [[...]

16 2) Defrost Timer The defrost cycle starts when the Float Switch opens and completes the freeze cycle. But the Defrost Timer does not start counting until the Thermistor senses 48°F at the Evaporator outlet. The period from the end of the freeze cycle up to the point of the Thermistor's sensing varies depending on the ambient and water temp[...]

17 problem occurs. At startup a 5 second delay occurs while the board conducts an internal timer check. A short beep occurs when the power switch is turned ON or OFF. The green LED’s 1-4 represent the corresponding relays and energize and sequence 5 seconds from initial startup as follows: Sequence Step LED’s on Length: Min. Max. Avg. 1 Minute [...]

18 (Control Product s HOS-001A Board) to the K1 connector. If there is a white wire, place the switch in the C position. If this switch is placed in the wrong position either the compressor contactor will remain ener- gized with the control switch OFF or the unit will not start. The dip switches should be adjusted per the adjustment chart published[...]

19 [c] SEQUENCE 1st Cycle 1. Unit energized and Control Switch to “ICE” position. Water supply cycle starts. 2. After 1 minute, Defrost cycle starts. 3. Thermistor reads 48° F. Defrost Timer starts counting. IMPORTANT Water Valve opening is limited to 6 minutes. & 5. After the first 5 minutes in freeze cycle. Ready to complete freeze cycle[...]

20 2nd Cycle and after with pump drain IMPORTANT Freeze cycle time is limited to 60 minutes even if Float Switch does not open. 1. Float Switch opens and signals to complete freeze cycle. Drain timer starts counting. 2. Drain timer stops counting. Pump drain is completed 3. Thermistor reads 48° F. Defrost Timer starts counting. IMPORTANT Water Val[...]

21 2nd Cycle and after with no pump drain IMPORTANT Freeze cycle time is limited to 60 minutes even if Float Switch does not open. 1. Float Switch opens and signals to complete freeze cycle. 2. Thermistor reads 48° F. Defrost Timer starts counting. IMPORTANT Water Valve opening is limited to 6 minutes. 4. After the first 5 minutes in freeze cycle.[...]

22 DIP SWITCH NO. 1 2 3 4 5 6 7 8 9 10 KM-900MRF/3 OFF OFF ON OFF ON ON OFF OFF OFF ON KM-900MAF, OFF OFF ON OFF ON ON OFF OFF OFF ON KM-900MWF [d] CONTROLS AND ADJUSTMENTS The Dip Switch is factory-adjusted to the following positions: Switch Nos. 1 and 2: Used for adjustment of the Defrost Timer. The Defrost Timer starts counting when the Thermist[...]

23 1) Defrost Control A thermistor (Semiconductor) is used for a defrost control sensor. The resistance var- ies depending on the Suction Line temperatures. The Thermistor detects the tempera- ture of the Evaporator outlet to start the Defrost Timer. No adjustment is required. If necessary, check for resistance between Thermistor leads, and visuall[...]

24 3) Drain Timer The Drain Timer is factory-adjusted, and no adjustment is required. SETTING TIME Dip Switch Dip Switch No. 3 No. 4 T1 T2 OFF OFF 10 seconds 150 seconds ON OFF 10 seconds 180 seconds OFF ON 10 seconds 120 seconds ON ON 20 seconds 180 seconds T1: Time to drain the Water Tank T2: Time to restrain defrost completion 4) Drain Counter C[...]

25 6) Bin Control CAUTION When the ambient temperature is below 45°F, the Bin Control Thermostat operates to stop the icemaker even if the Ice Storage Bin is empty. When the Thermostat is set in the prohibited range, the icemaker operates continuously even if the Ice Storage Bin is filled with ice. Setting in the prohibited range might cause sever[...]

26 (iv) After Step (iii), de-energize the unit and confirm that the Defrost Timer is in the minimum position. Disconnect the resistor from the Controller Board, and ener- gize the unit. After the 1 minute water supply cycle, the defrost cycle starts. Re-connect a 1.5 k Ω - 3.5 k Ω resistor to the Connector K3 (pins #1 and #2) after the first 2 [...]

27 III. TECHNICAL INFORMA TION 1. WATER CIRCUIT AND REFRIGERANT CIRCUIT [a] KM-900MAF[...]

28 [b] KM-900MWF[...]

29 [c] KM-900MRF and KM-900MRF3[...]

30 2. WIRING DIAGRAMS [a] KM-900MAF Note: Pressure Switch Cut-out 412 ± PSIG Cut-in 327 ± 21 PSIG 21 0[...]

31 [b] KM-900MWF Note: Pressure Switch Cut-out 412 ± PSIG Cut-in 327 ± 21 PSIG 21 0[...]

32 [c] KM-900MRF Note: Pressure Switch Cut-out 412 ± PSIG Cut-in 327 ± 21 PSIG 21 0[...]

33 [d] KM-900MRF3 Note: Pressure Switch Cut-out 412 ± PSIG Cut-in 327 ± 21 PSIG 21 0[...]

34 3. TIMING CHART Control Sw. in ICE Bin Thermo- stat ON Pressure Sw. ON Overheat Protect Reset Hi Temp Mid Temp Lo Temp Too Lo Temp Normal Too Hi Temp Lo Water Max. Min. 60 min 5 min Min. Max. Max. 2 min 6 min 6 min Max. 20 min Time Up (60 sec) If Float Sw. is OFF From Defrost Cycle When Control Sw. is turned OFF, Pressure Sw. is OFF, or Thermist[...]

35 To Freeze Cycle To Stand-by Cycle (When Control Sw. is turned OFF, Pressure Sw. is OFF, or Thermistor Temp. exceeds t1.) From Freeze Cycle Control Sw. in WASH Min. Max. Max. 3 min 6 min 6 min Max. 20 min *1 The Pump Motor waits for 2 seconds before starting a drain cycle. See “II. 2. [d] CONTROLS AND ADJUSTMENTS.” *2 The icemaker does not co[...]

36 4. PERFORMANCE DATA [a] KM-900MAF Note: Pressure data is recorded at 5 minutes into freeze cycle. The data not in bold should be used for reference only. * We reserve the right to make changes in specifications and design without prior notice.[...]

37 [b] KM-900MWF Note: Pressure data is recorded at 5 minutes into freeze cycle. The data not in bold should be used for reference only. * We reserve the right to make changes in specifications and design without prior notice.[...]

38 [c] KM-900MRF Note: Pressure data is recorded at 5 minutes into freeze cycle. The data not in bold should be used for reference only. * We reserve the right to make changes in specifications and design without prior notice.[...]

39 [b] KM-900MRF3 Note: Pressure data is recorded at 5 minutes into freeze cycle. The data not in bold should be used for reference only. * We reserve the right to make changes in specifications and design without prior notice.[...]

40 PROBLEM POSSIBLE CAUSE REMEDY [1] The icemaker a) Power Supply 1. “OFF” position. 1. Move to “ON” position will not start 2. Loose connections. 2. Tighten 3. Bad contacts. 3. Check for continuity and replace. 4. Voltage too high. 4. Check and get recommended voltage. b) Fuse (Inside Fused 1. Blown out. 1. Check for short circuit Disconne[...]

41 PROBLEM POSSIBLE CAUSE REMEDY l) Controller Board 1. Defective 1. See “II.2[e] CHECKING CONTROLLER BOARD.” m) Interlock Switch 1. “OFF” position. 1. Move to “ON” position. (Cleaning Valve) 2. Bad contacts. 2. Check for continuity and replace. [2] Water a) Float switch 1. Connector disconnected. 1. Place in position. continues to 2. L[...]

42 PROBLEM POSSIBLE CAUSE REMEDY [4] Water a) Water Solenoid 1. Diaphragm does not close. 1. Check for water leaks continues to Valve with icemaker off. be supplied in b) Controller Board 1. Defective. 1. See “II.2.[e] CHECKING freeze cycle. CONTROLLER BOARD.” [5] No water a) Water Supply Line 1. Water pressure too low and 1. Check and get come[...]

43 PROBLEM POSSIBLE CAUSE REMEDY [1] Freeze cycle a) See chart 1 - [3], and check dirty Air Filter or Condenser, ambient or water time is long. temperature, water pressure, Water Regulator or refrigerant charge. b) See chart 2 - [1], and check Float Switch, Water Solenoid Valve or Controller Board. [2] Harvest cycle a) See chart 2 - [2], and check [...]

44 PROBLEM POSSIBLE CAUSE REMEDY [1] Icemaker will a) Bin Control 1. Set too cold. 1. Adjust warmer. not stop when Thermostat 2. Defective. 2. Replace. bin is filled with ice. [2] Abnormal a) Pump Motor 1. Bearings worn out. 1. Replace. noise b) Fan Motor 1. Bearings worn out. 1. Replace. 2. Fan blade deformed. 2. Replace fan blade. 3. Fan blade do[...]

45 V. REMOVAL AND REPLACEMENT OF COMPONENTS IMPORTANT Ensure all components, fasteners and thumbscrews are securely in place after the equipment is serviced. IMPORTANT 1. The Polyol Ester (POE) oils used in R-404A units can absorb moisture quickly. Therefore it is important to prevent moisture from entering the system when replacing or servicing pa[...]

46 5) Disconnect the Vacuum Pump, and attach a Refrigerant Service Cylinder to the High- side line. Remember to loosen the connection, and purge the air from the Hose. See the Nameplate for the required refrigerant charge. Hoshizaki recommends only virgin refrigerant or reclaimed refrigerant which meets ARI Standard No. 700-88 be used. 6) A liquid [...]

47 3. REMOV AL AND REPLACEMENT OF COMPRESSOR IMPORT ANT Always install a new Drier every time the sealed refrigeration system is opened. Do not replace the Drier until after all other repair or replacement has been made. Note: When replacing a Compressor with a defective winding, be sure to install the new Start Capacitor and Start Relay supplied w[...]

48 15) Evacuate the system, and charge it with refrigerant. For air-cooled and water-cooled models, see the Nameplate for the required refrigerant charge. For remote air-cooled models, see the Charge Label in the machine compartment. 16) Connect the Terminals, and replace the Terminal Cover in its correct position. 17) Replace the panels in their c[...]

49 4. REMOV AL AND REPLACEMENT OF DRIER IMPORT ANT Always install a new Drier every time the sealed refrigeration system is opened. Do not replace the Drier until after all other repair or replacement has been made. 1) Turn off the power supply. 2) Remove the panels. 3) Recover the refrigerant and store it in an approved container. 4) Remove the Dr[...]

50 3) Recover the refrigerant and store it in an approved container. 4) Remove the insulation and the Expansion Valve Bulb on the suction line. 5) Remove the Expansion Valve Cover, and disconnect the Expansion Valve using brazing equipment. 6) Braze the new Expansion Valve, with nitrogen gas flowing at the pressure of 3-4 PSIG. W ARNING Always prot[...]

51 IMPORT ANT Always install a new Drier every time the sealed refrigeration system is opened. Do not replace the Drier until after all other repair or replacement has been made. 1) Turn off the power supply. 2) Remove the panels. 3) Recover the refrigerant and store it in an approved container. 4) Remove the screw and the Solenoid. 5) Disconnect t[...]

52 7. REMOV AL AND REPLACEMENT OF EV APORA TOR IMPORT ANT Always install a new Drier every time the sealed refrigeration system is opened. Do not replace the Drier until after all other repairs or replacement have been made. 1) Turn off the power supply. 2) Remove the panels and the Top Insulation over the Evaporator. 3) Recover the refrigerant and[...]

53 8. REMOV AL AND REPLACEMENT OF W A TER REGULA TING V AL VE - W A TER-COOLED MODEL ONL Y IMPORT ANT Always install a new Drier every time the sealed refrigeration system is opened. Do not replace the Drier until after all other repair or replacement has been made. 1) Turn off the power supply. 2) Close the Water Supply Line Shut-off Valve. 3) Rem[...]

54 9. ADJUSTMENT OF W A TER REGULA TING V AL VE - W A TER-COOLED MODEL ONL Y The Water Regulating Valve (also called “WATER REGULATOR”) is factory-adjusted. No adjustment is required under normal use. Adjust the Water Regulator, if necessary, using the following procedures. 1) Attach a pressure gauge to the high-side line of the system. Or prep[...]

55 10. REMOV AL AND REPLACEMENT OF CONDENSING PRESSURE REGULA T OR (C.P .R.) - REMOTE AIR-COOLED MODEL ONL Y IMPORT ANT Always install a new Drier every time the sealed refrigeration system is opened. Do not replace the Drier until after all other repair or replacement has been made. 1) Turn off the power supply. 2) Remove the panels from the remot[...]

56 1 1. REMOV AL AND REPLACEMENT OF THERMIST OR CAUTION 1. Fragile, handle very carefully. 2. Always use a recommended sealant (High Thermal Conductive Type), Model KE4560RTV manufactured by SHINETSU SILICONE, Part Code 60Y000-11, or Part Code 4A0683-01 equivalent. 3. Always use a recommended foam insulation (Non-absorbent Type) or equivalent. 4. D[...]

57 Min. 4-3/4" Liquid Bypass Flow 10) Secure the insulation using the Plastic Cable Ties. 11) Connect the Thermistor leads through the bushing of the Control Box to the K3 Connector on the Controller Board. Note: Do not cut the leads of the Thermistor while installing it. 12) Replace the Control Box Cover and the panels in their correct positi[...]

58 13. REMOV AL AND REPLACEMENT OF W A TER V AL VE 1) Turn off the power supply. 2) Close the Water Supply Line Shut-off Valve. 3) Remove the Front Panel. 4) Remove the Valve Outlet Tubing by releasing the Clamp. 5) Remove the Bracket from the unit. 6) Remove the Fitting Nut and Water Valve. 7) Disconnect the Terminals from the Water Valve. 8) Inst[...]

59 8) Remove the closed end connectors from the Pump Motor leads. 9) Remove the two screws and the Pump Motor Bracket. 10) Remove the Pump Housing, and check the Impeller. 11) If the Impeller is defective, install a new Impeller. 12) Install the new motor or new parts, and replace the removed parts in the reverse order of which they were removed. 1[...]

60 VI. MAINTENANCE AND CLEANING INSTRUCTIONS IMPORTANT Ensure all components, fasteners and thumbscrews are securely in place after any maintenance or cleaning is done to the equipment. 1. PREPARING THE ICEMAKER FOR LONG STORAGE WARNING When shutting off the icemaker for an extended time, drain out all water from the water tank and remove the ice f[...]

61 [2] Remove the water from the potable water supply line: 1) Remove the Front Panel. (Except water-cooled model) 2) Move the Control Switch, on the Control Box, to the “OFF” position. 3) Wait 3 minutes. 4) Close the Potable Water Supply Line Shut-off Valve and open the Potable Water Supply Line Drain Valve. 5) Allow the line to drain by gravi[...]

62 CLOSED POSITION OPEN POSITION 2. CLEANING IMPORTANT Ensure all components, fasteners and thumbscrews are securely in place after any maintenance or cleaning is done to the equipment. WARNING 1. HOSHIZAKI recommends cleaning this unit at least once a year. More frequent cleaning, however, may be required in some existing water conditions. 2. To p[...]

63 [a] CLEANING PROCEDURE 1) Dilute 16 fl. oz. of the recommended cleaner Hoshizaki “Scale Away” or “LIME-A-WAY” (Economics Laboratory, Inc.) with 3 gallons of water. 2) Remove all ice from the Evaporator and the Storage Bin. Note: To remove cubes on the Evaporator, turn off the power supply and turn it on after 3 minutes. The defrost cycle[...]

64 20) Turn on the power supply to fill the Water Tank with water. 21) Turn off the power supply after 3 minutes. 22) Remove the Front Panel, and fully open the Cleaning Valve. 23) Move the Control Switchto the “Wash” position. 24) Replace the Front Panel in its correct position. 25) Turn on the power supply to rise off the cleaning solution. 2[...]

65 8) Drain the Water Tank. See the above step 5) in “[a] CLEANING PROCEDURE.” 9) Replace the removed parts and the Insulation Panel in their correct positions. 10) Repeat the above steps 15) through 28) in “[a] CLEANING PROCEDURE” two times to rinse thoroughly. 11) Close the Cleaning Valve. 12) Move the Control Switch to the “ICE” posi[...]