Hoshizaki KM-500MAF, Service Manual

Page 1: ...NO ISSUED REVISED HOSHIZAKI MODULAR CRESCENT CUBER SERVICE MANUAL KM 500MAF KM 500MWF KM 500MRF MODEL APRIL9 1999 73086 DEC 16 2003 ...

Page 2: ...00 233 1940TechnicalService 770 487 2331 Fax 770 487 3360 NOTE Toexpediteassistance allcorrespondence communicationMUST includethefollowing information Model Number Serial Number Completeanddetailedexplanationoftheproblem HOSHIZAKI provides this manual primarily to assist qualified service technicians in the service and maintenance of the icemaker Should the reader have any questions or concerns w...

Page 3: ...ater cooled 11 c KM 500MRF Remote air cooled 12 2 CONTROLLER BOARD 13 a SOLID STATE CONTROL 13 b CONTROLLER BOARD 13 c SEQUENCE 17 d CONTROLS AND ADJUSTMENTS 20 e CHECKING CONTROLLER BOARD 23 III TECHNICAL INFORMATION 25 1 WATER CIRCUIT AND REFRIGERANT CIRCUIT 25 a KM 500MAF Air cooled 25 b KM 500MWF Water cooled 26 c KM 500MRF Remote air cooled 27 2 WIRING DIAGRAMS 28 a KM 500MAF Air cooled and K...

Page 4: ...ULATING VALVE WATER COOLED MODEL ONLY 48 9 ADJUSTMENT OF WATER REGULATING VALVE WATER COOLED MODEL ONLY 49 10 REMOVAL AND REPLACEMENT OF CONDENSING PRESSURE REGULATOR C P R REMOTE AIR COOLED MODEL ONLY 50 11 REMOVAL AND REPLACEMENT OF THERMISTOR 51 12 REMOVAL AND REPLACEMENT OF FAN MOTOR 52 13 REMOVAL AND REPLACEMENT OF WATER VALVE 53 14 REMOVAL AND REPLACEMENT OF PUMP MOTOR 53 15 REMOVAL AND REPL...

Page 5: ...5 I SPECIFICATIONS 1 KM 500MAF Note We reserve the right to make changes in specifications and design without prior notice ...

Page 6: ...6 2 KM 500MWF Note We reserve the right to make changes in specifications and design without prior notice ...

Page 7: ...7 3 KM 500MRF Note We reserve the right to make changes in specifications and design without prior notice ...

Page 8: ... 1 8 460 mm 20 15 32 520 mm 21 15 16 557 mm 7 8 DIA HOLE 23 mm DIA 6 5 16 160 mm 2 15 16 75 mm 18 1 8 460 mm 6 16 x 3 4 10 mm x 20 mm 4 x 2 SLOTTED HOLES 17 1 8 435 mm 14 9 16 370 mm 14 1 8 358 mm 14 15 16 380 mm 15 11 16 398 mm 17 7 8 454 mm 2 1 2 63 mm 14 15 16 380 mm ...

Page 9: ...g 68 lbs 31 kg One Shot Couplings Aeroquip Permanent Connection Air cooled Condensing Pressure Regulator Min 20 F Max 122 F 29 C to 50 C Outdoor use SPECIFICATIONS EXTERIOR DIMENSIONS W x D x H REFRIGERANT CHARGE WEIGHT CONNECTIONS REFRIGERANT ELECTRICAL CONDENSER HEAD PRESSURE CONTROL AMBIENT CONDITION MODEL URC 6F ...

Page 10: ...FORMATION 1 CONSTRUCTION a KM 500MAF Spray Tubes Water Supply Inlet Control Switch Condenser Bin Control Thermostat Hot Gas Valve Expansion Valve Fan Motor Condenser Compressor Drier Float Switch Control Box Water Pump ...

Page 11: ...11 b KM 500MWF Spray Tubes Water Supply Inlet Control Switch Water Regulator Bin Control Thermostat Expansion Valve Hot Gas Valve Compressor Float Switch Drier Water Pump Control Box ...

Page 12: ...12 c KM 500MRF Spray Tubes Water Supply Inlet Control Switch Junction Box Bin Control Thermostat Expansion Valve Receiver Tank Compressor Float Switch Drier Water Pump Hot Gas Valves Control Box ...

Page 13: ...ng the board 3 Do not touch the electronic devices on the board or the back of the board to prevent damage to the board 4 Do not change wiring and connections Do not misconnect K3 K4 and K5 because the same connector is used for the Thermistor and Float Switch K4 is not connected 5 Always replace the whole board assembly when it goes bad 6 Do not short out power supply to test for voltage PART NUM...

Page 14: ...et the Safety 4 Low Water Safety If the Pump Motor is operated without water the mechanical seal can fail To prevent this type of failure the Controller Board checks the position of the Float Switch at the end of the initial one minute water fill cycle and at the end of each defrost cycle If the Float Switch is in the up position electrical circuit closed the Controller Board changes to the ice ma...

Page 15: ...ck for open thermistor HGV not opening TXV leaking by low charge or inefficient compressor 3 beeps every 3 sec Freeze Back Up Timer Freeze 60 minutes Yellow LED marked 60 MIN energizes Check for F S stuck closed up WV leaking by HGV leaking by TXV not feeding prop erly low charge or inefficient compressor To manually reset the above safeties depress white alarm reset button with the power supply O...

Page 16: ...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 in the Tech Specs book 7 8 must remain in the OFF position ...

Page 17: ...st 5 minutes in freeze cycle Ready to complete freeze cycle when Float Switch circuit opens 4 Defrost Timer stops counting Defrost cycle is completed and freeze cycle starts IMPORTANT Board never accepts freeze completion signal within the first 5 minutes in freeze cycle IMPORTANT 1 Board never accepts defrost completion signal within the first 2 minutes in defrost cycle 2 Defrost cycle time is li...

Page 18: ...ANT Water Valve opening is limited to 6 minutes 5 After the first 5 minutes in freeze cycle Ready to complete freeze cycle when Float Switch circuit opens 4 Defrost Timer stops counting Defrost cycle is completed and freeze cycle starts IMPORTANT Board never accepts freeze completion signal within the first 5 minutes in freeze cycle IMPORTANT 1 Board never accepts defrost completion signal within ...

Page 19: ... minutes 4 After the first 5 minutes in freeze cycle Ready to complete freeze cycle when Float Switch circuit opens 3 Defrost Timer stops counting Defrost cycle is completed and freeze cycle starts IMPORTANT Board never accepts freeze completion signal within the first 5 minutes in freeze cycle IMPORTANT 1 Board never accepts defrost completion signal within the first 2 minutes in defrost cycle 2 ...

Page 20: ...nd the icemaker resumes operation in 2 seconds Then the Pump Motor drains the Water Tank for the time determined by the Drain Timer The Drain Timer also determines the time to restrain completion of a defrost cycle i e the minimum defrost time Switch Nos 5 and 6 Used for adjustment of the Drain Counter The Pump Motor drains the Water Tank at the frequency determined by the Drain Counter Switch Nos...

Page 21: ... the connector K3 on the board ii Remove the Thermistor See V 11 REMOVAL AND REPLACEMENT OF THER MISTOR iii Immerse the Thermistor sensor portion in a glass containing ice and water for 2 or 3 minutes iv Check for a resistance between Thermistor leads Normal reading is within 3 5 to 7 kΩ Replace the Thermistor if it exceeds the normal reading 2 Defrost Timer No adjustment is required under normal ...

Page 22: ...strain defrost completion 4 Drain Counter CAUTION Do not adjust the Drain Counter or the Evaporator may freeze up The Drain Counter is factory adjusted to drain the Water Tank every 10 cycles and no adjustment is required However where water quality is bad and the icemaker needs a pump drain more often the Drain Counter can be adjusted as shown in the table below SETTING FREQUENCY Dip Switch Dip S...

Page 23: ...e sequence with the icemaker operating 2 Visually check the Controller Board by using the following procedures i Adjust the Defrost Timer to minimum position Disconnect the Thermistor from the Controller Board Connect a 1 5 kΩ 3 5 kΩ resistor to the Connector K3 pins 1 and 2 and energize the unit 5 Freeze Timer CAUTION Adjust to proper specification or the unit may not operate correctly Two new di...

Page 24: ...With power OFF place S3 on and switch power to ICE The correct lighting sequence should be none 2 3 4 1 and 4 normal sequence every 5 seconds S3 should remain in the OFF position for normal operation After the 1 minute 5 second water supply cycle and the 2 minute 10 second defrost cycle the unit should start the freeze cycle ii After the above step i disconnect the Float Switch leads from the Cont...

Page 25: ...25 III TECHNICAL INFORMATION 1 WATER CIRCUIT AND REFRIGERANT CIRCUIT a KM 500MAF ...

Page 26: ...26 b KM 500MWF ...

Page 27: ...27 c KM 500MRF ...

Page 28: ...28 2 WIRING DIAGRAMS a KM 500MAF and KM 500MWF Note Pressure Switch Cut out 412 PSIG Cut in 327 21 PSIG 21 0 ...

Page 29: ...29 b KM 500MRF U1GMA0179608 Note Pressure Switch Cut out 412 PSIG Cut in 327 21 PSIG 21 0 ...

Page 30: ...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 Thermistor Temp exceeds t1 To Defrost Cycle NOTE The icemaker does not complete a defrost cycle in the first 2 or 3 minutes See II 2 d CONTROLS AND ADJUSTMENTS ...

Page 31: ...ceeds t1 From Freeze Cycle Control Sw in WASH 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 complete a defrost cycle in the first 2 or 3 minutes See II 2 d CONTROLS AND ADJUSTMENTS 2 2 1 Min Max Max 3 min 6 min 6 min ...

Page 32: ...ATA a KM 500MAF 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 ...

Page 33: ...500MWF 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 ...

Page 34: ...500MRF 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 ...

Page 35: ...ty and Control replace f Transformer 1 Thermal fuse blown out 1 Replace or coil winding opened g Wiring to 1 Loose connections or 1 Check for continuity and Controller Board open replace h Thermistor 1 Leads short circuit or 1 See II 2 d CONTROLS open and High AND ADJUSTMENTS 1 Temperature Safety Defrost Control operates i Hot Gas Solenoid 1 Continues to open in 1 Check for power off in Valve free...

Page 36: ...t 1 6 water cooled model 6 Refrigerant line or 6 Clean and replace Drier components plugged c Water Regulator 1 Set too high 1 Adjust lower d Overload Protector 1 Bad contacts 1 Check for continuity and replace 2 Voltage too low 2 Increase voltage 3 Refrigerant overcharged or 3 Recharge undercharged 4 Line Valve continues to 4 Check Line Valve s close in freeze cycle and operation in freeze cycle ...

Page 37: ...Controller Board 1 Defective 1 See II 2 e CHECKING CONTROLLER BOARD 6 Fan Motor will a Fan Motor 1 Motor winding opened 1 Replace not start or is 2 Bearing worn out 2 Replace not operating 3 Wiring to Fan Motor 3 Check for loose connection or open and replace 4 Defective Capacitor 4 Replace 5 Fan blade bound 5 Check and replace b Controller Board 1 Defective 1 See II 2 e CHECKING CONTROLLER BOARD ...

Page 38: ...ation in harvest cycle harvest cycle and replace f Thermistor 1 Out of position or loose 1 See V 11 REMOVAL attachment AND REPLACEMENT OF THERMISTOR g Controller Board 1 Defrost Timer is set too 1 Adjust longer referring short to II 2 d CONTROLS AND ADJUSTMENT 2 Defrost Timer 2 Defective 2 See II 2 e CHECKING CONTROLLER BOARD 3 Others a Spray Tubes 1 Clogged 1 Clean 2 Out of position 2 Place in po...

Page 39: ...hart 1 5 and check water supply line Water Solenoid Valve water system Pump Motor or Controller Board c Drain Valve 1 Dirty 1 Clean 2 Cloudy or a See chart 2 1 and 3 and check Float Switch Water Solenoid Valve irregular cube Controller Board Spray Tubes water system refrigerant charge or Expansion Valve b Spray Guide 1 Dirty 1 Clean c Water Quality 1 High hardness or contains 1 Install a water fil...

Page 40: ...gerant Access Valves one on the low side and one on the high side line Using proper refrigerant practices recover the refrigerant from the Access Valves and store it in an approved container Do not discharge the refrigerant into the atmosphere b EVACUATION AND RECHARGE R 404A 1 Attach Charging Hoses a Service Manifold and a Vacuum Pump to the system Be sure to connect charging hoses to both High a...

Page 41: ...rant Access Valves and disconnect the Hoses and Service Manifold 10 Cap the Access Valves to prevent a possible leak 2 BRAZING DANGER 1 Refrigerant R 404A itself is not flammable at atmospheric pressure and temperatures up to 176 F 2 Refrigerant 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 c...

Page 42: ...power supply 2 Remove the panels 3 Recover the refrigerant and store it in an approved container 4 Remove the Terminal Cover on the Compressor and disconnect the Compressor Wiring 5 Remove the Discharge and Suction Pipes using brazing equipment 6 Remove the Hold down Bolts Washers and Rubber Grommets 7 Slide and remove the Compressor Unpack the new Compressor package Install the new Compressor 8 A...

Page 43: ...dels 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 correct positions 18 Turn on the power supply ...

Page 44: ...ks using nitrogen gas 140 PSIG and soap bubbles 7 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 8 Replace the panels in their correct positions 9 Turn on the power supply 5 REMOVAL AND REPLACEMENT OF EXPANSION VALVE IMPORTANT...

Page 45: ...aks using nitrogen gas 140 PSIG and soap bubbles 9 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 10 Attach the Bulb to the suction line in position Be sure to secure it with clamps and to insulate it 11 Place the new set of E...

Page 46: ... to prevent the valve from overheating Do not braze with the valve body exceeding 250 F 7 Install the new Drier 8 Check for leaks using nitrogen gas 140 PSIG and soap bubbles 9 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 10...

Page 47: ...sis 5 Remove the Insulation Tube and disconnect the Evaporator Inlet Tubing at the Tee next to the Expansion Valve 6 Lift up the Evaporator and disconnect the Evaporator Outlet Tubing 7 Install the new Evaporator 8 Install the new Drier 9 Check for leaks using nitrogen gas 140 PSIG and soap bubbles 10 Evacuate the system and charge it with refrigerant For air cooled and water cooled models see the...

Page 48: ...r 5 Disconnect the Capillary Tube at the Condenser outlet using brazing equipment 6 Disconnect the Flare connections of the valve 7 Remove the screws and the valve from the Bracket 8 Install the new valve and braze the Capillary Tube 9 Install the new Drier 10 Check for leaks using nitrogen gas 140 PSIG and soap bubbles 11 Evacuate the system and charge it with refrigerant See the Nameplate for th...

Page 49: ...stem Or prepare a thermometer to check for the condenser drain temperature 2 Rotate the adjustment screw by using a flat blade screwdriver so that the pressure gauge shows the temperature specified in the table 5 minutes after a freeze cycle or icemaking process starts When the pressure exceeds 270 PSIG or the condenser drain temperature exceeds the temperature range rotate the adjustment screw co...

Page 50: ...k off the stub on the dome to release the dome charge 5 Disconnect the C P R using brazing equipment 6 Install the new C P R Use nitrogen gas at the pressure of 3 4 PSIG when brazing the C P R WARNING Always protect the C P R body by using a damp cloth to prevent the C P R from overheating Do not braze with the C P R body exceeding 250 F 7 Install the new Drier in the icemaker 8 Check for leaks us...

Page 51: ...ol Box Cover 4 Disconnect the Thermistor leads from the K3 Connector on the Controller Board 5 Remove the Plastic Cable Ties Foam Insulation Thermistor Holder and Thermistor See Fig 2 6 Scrape away the old sealant on the Thermistor Holder and the Suction Pipe 7 Wipe off moisture or condensation on the Suction Pipe 8 Smoothly apply recommended sealant KE4560RTV Part Code 60Y000 11 or 4A0683 01 to t...

Page 52: ...ller 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 positions 13 Turn on the power supply 12 REMOVAL AND REPLACEMENT OF FAN MOTOR Note When replacing a Fan Motor with defective winding it is recommended that a new capacitor be installed 1 Turn off the power supply 2 Remove the panels 3 Remove the Junction Box C...

Page 53: ...e 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 Install the new Water Valve and replace the removed parts in the reverse order of which they were removed 9 Open the Water Supply Line Shut off Valve 10 Turn on the power suppl...

Page 54: ...nd replace the removed parts in the reverse order of which they were removed 13 Turn on the power supply and check for leaks 14 Replace the Base Cover in its correct position 15 Replace the Front Panel in its correct position 15 REMOVAL AND REPLACEMENT OF SPRAY TUBES 1 Turn off the power supply 2 Remove the Front Panel and the Insulation Panel 3 Remove the Rubber Hoses from the Spray Tubes Water S...

Page 55: ...ays it is sufficient to only move the Control Switch to the OFF position unless the icemaker will be at sub freezing temperatures 1 On water cooled model only first remove the water from the water cooled condenser 1 Remove the Front Panel 2 Move the Control Switch on the Control Box to the OFF position 3 Wait 3 minutes 4 Move the Control Switch to the ICE position 5 Allow 5 minutes for the icemake...

Page 56: ...dioxide supply to the Potable Water Line Drain Valve 7 Move the Control Switch to the ICE position 8 Blow the potable water line out using compressed air or carbon dioxide 3 Drain the Potable Water Tank 1 Turn off the power supply 2 Move the Control Switch to the OFF position 3 Drain the Water Tank by removing the base cover and one end of the pump tubing See Fig 4 4 Replace the removed parts in t...

Page 57: ...3 Always wear liquid proof gloves for safe handling of the cleaning and sanitizing solution This will prevent irritation in case the solution comes into contact with skin IMPORTANT 1 The Cleaning Valve is used to allow solution flow to the inside of the Evaporator during the cleaning and sanitizing operation It should be closed for all icemaking operation The Compressor will not operate unless thi...

Page 58: ...Tank by removing one end of the Pump Tubing See Fig 4 7 Replace the removed parts in their correct positions 8 Pour the cleaning solution into the Water Tank 9 Fully open the Cleaning Valve on the left side wall of the machine compartment 10 Move the Control Switch on the Control Box to the WASH position 11 Replace the Insulation Panel and the Front Panel in their correct positions 12 Turn on the ...

Page 59: ...25 Turn on the power supply to rise off the cleaning solution 26 Turn off the power supply after 5 minutes 27 Remove the Front Panel and Insulation Panel 28 Drain the Water Tank by removing one end of the Pump Tubing See Fig 4 29 Replace the removed parts in their correct positions Note Do not replace the InsulationPanel when you proceed to b SANITIZING PROCEDURE 28 Repeat the above steps 17 throu...

Page 60: ... is open 5 Turn on the power supply and start the sanitizing process 6 Turn off the power supply after 15 minutes 7 Remove the Front Panel and if necessary the Insulation Panel 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 position 10 Repeat the above steps 17 through 29 in a CLEANING PROCEDURE two times to...

Page 61: ...up 2 Storage Bin and Scoop Wash your hands before removing ice Use the plastic scoop provided The Storage Bin is for ice use only Do not store anything else in the bin Keep the scoop clean Clean it by using a neutral cleaner and rinse thoroughly Clean the bin liner by using a neutral cleaner Rinse thoroughly after cleaning 3 Condenser Except water cooled model Check the Condenser once a year and c...