Hoshizaki KM-600MAH, Service Manual

Page 1: ...1 Hoshizaki A Superior Degree of Reliability www hoshizaki com Model KM 600MAH Modular Crescent Cuber Hoshizaki America Inc SERVICE MANUAL Number 73167 Issued 8 12 2008 Revised 8 25 2008 ...

Page 2: ...r Should the reader have any questions or concerns which have not been satisfactorily addressed please call write or send an e mail message to the Hoshizaki Technical Support Department for assistance HOSHIZAKI AMERICA INC 618 Highway 74 South Peachtree City GA 30269 Attn Hoshizaki Technical Support Department Phone 1 800 233 1940 Technical Service 770 487 2331 Fax 1 800 843 1056 770 487 3360 E ma...

Page 3: ... 15 d Pump Out Frequency Control S4 dip switch 5 6 15 e Factory Use S4 dip switch 7 8 15 f Freeze Timer S4 dip switch 9 10 16 4 Control Board Check Procedure 16 5 Control Board Replacement 17 D Harvest Control Thermistor 17 1 Thermistor Check 17 E Float Switch 17 1 Float Switch Check 17 2 Float Switch Cleaning 18 F Bin Control 19 III Technical Information 20 A Water Circuit and Refrigeration Circu...

Page 4: ...d Replacement of Compressor 34 C Removal and Replacement of Expansion Valve 35 D Removal and Replacement of Hot Gas Valve 36 E Removal and Replacement of Evaporator 37 F Removal and Replacement of Thermistor 38 G Removal and Replacement of Fan Motor 39 H Removal and Replacement of Inlet Water Valve 39 I Removal and Replacement of Pump Motor 40 VI Cleaning and Maintenance 41 A Cleaning and Sanitizi...

Page 5: ...nless Steel Galvanized Steel Rear WEIGHT Net 169 lbs 77 kg Shipping 200 lbs 91 kg CONNECTIONS ELECTRIC Permanent Connection WATER SUPPLY Inlet 1 2 FPT DRAIN Outlet 3 4 FPT 3 8 OD Tube CUBE CONTROL SYSTEM Float Switch HARVESTING CONTROL SYSTEM Hot Gas and Water Thermistor and Timer ICE MAKING WATER CONTROL Timer Controlled Overflow Pipe COOLING WATER CONTROL N A BIN CONTROL SYSTEM Thermostat COMPRE...

Page 6: ...ormation A Construction 1 KM 600MAH air cooled Bin Control Thermostat Control Switch Expansion Valve Compressor Float Switch Water Pump Control Box Drier Fan Motor Hot Gas Valve Condenser Water Supply Pipe Spray Tubes ...

Page 7: ...f 6 minutes or the length of harvest whichever is shorter At the end of harvest the control board checks the position of F S and proceeds to the freeze cycle if it is closed or calls for a 1 minute fill if it is open 3 Freeze Cycle LED 1 is on Comp continues to run PM and FMS energize HGV and WV close and the freeze cycle starts For the first 5 minutes the control board will not accept a signal fr...

Page 8: ... 60 90 120 and 180 seconds For details see II C 3 b Harvest Timer S4 Dip Switch 1 2 When the harvest timer completes its countdown the harvest cycle is complete and the freeze cycle starts The minimum total time allowed by the control board for a complete harvest cycle is 2 minutes WV is energized during harvest for a maximum of 6 minutes or the length of harvest whichever is shorter At the end of...

Page 9: ...lve KM 600MAH Sequence Flow Chart and Component Operation 1 One Minute Fill Cycle 2 Harvest Cycle 3 Freeze Cycle 4 Pump Out Cycle Cycle Steps WV Energized F S open F S closed Comp energized HGV energized WV continues Thermistor temp reaches 48 F 9 C 3 9 kΩ or less Harvest timer starts F S open Comp continues HGV de energized WV de energized PM energized FMS energized F S closed Freeze cycle operat...

Page 10: ...tic discharge It is especially important to touch the metal part of the unit before handling or replacing 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...

Page 11: ...h 10 1 9 Magnetic Contactor 2 Hot Gas Valve 3 Self Contained Fan Motor FMS 4 Pump Motor icemaking 5 Pump Motor pump out 6 Inlet Water Valve 7 10 Power Supply 8 Open Switch for C board and ALPINE board service boards only ALARM RESET Switch Backup Freeze Timer LED S4 Dip Switch Backup Harvest Timer LED Alarm Buzzer Power LED lights when power is supplied to the board Relay LEDs 4 indicate which rel...

Page 12: ...the control board must be pressed with power on to reset the safety d Low Water Safety The control board checks the position of the float switch at the end of the initial 1 minute water fill cycle and at the end of each harvest cycle If the float switch is in the up position electrical circuit closed the control board changes to the ice making cycle If the float switch is in the down position elec...

Page 13: ...larms as listed below No of Beeps every 3 sec Type of Alarm Notes 1 High Evaporator Temp temperature 127 F 53 C Check for harvest problem stuck HGV or relay hot water entering unit or shorted thermistor 2 Harvest Backup Timer harvest 20 min for two cycles in a row Orange LED marked H TIMER lights up Check for open thermistor HGV not opening TXV leaking by low charge or inefficient Comp 3 Freeze Ti...

Page 14: ...he harvest timer starts counting when the thermistor reaches 48 F 9 C at the evaporator outlet and the control board reads the thermistor s 3 9 kΩ signal The harvest timer is factory adjusted and no adjustment is required However a setting longer than the factory setting may be advised in cases where the flush provided at harvest needs to be prolonged for extra cleaning Before changing this settin...

Page 15: ...timer at pump out Pump out always occurs after the 1st freeze cycle Then depending on the pump out frequency control setting dip switch 5 6 pump out occurs every cycle or every 2nd 5th or 10th cycle d Pump Out Frequency Control S4 dip switch 5 6 The pump motor drains the water tank at the frequency set by the pump out frequency control The pump out frequency control is factory adjusted to drain th...

Page 16: ...he LED is off check the control transformer secondary circuit The transformer secondary circuit includes the cleaning valve interlock switch Make sure the interlock switch is closed otherwise no control voltage is supplied to the K2 connector Transformer output is 10 5V at 115V primary input If the secondary circuit has proper voltage and the red LED is off the control board is bad and should be r...

Page 17: ...n the tank after the 1 minute fill cycle and after each harvest cycle The float switch 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 the float switch follow the steps below 1 Turn off the power supply 2 Remove the front panel and move the control switch to t...

Page 18: ...urn off the power supply 2 Remove the front panel and move the control switch to the OFF position Remove the base cover Remove one end of the pump tubing See Fig 1 Allow the water to drain from the tank Replace the pump tubing and base cover in their correct positions 3 Remove the screws securing the float switch to the icemaker Remove the float switch from the rubber boot Remove the rubber boot 4...

Page 19: ...hibited range the icemaker operates continuously even if the ice storage bin is filled with ice Setting in the prohibited range might cause severe damage to the icemaker resulting in failure No adjustment is required under normal use as the bin control is factory adjusted Adjust it if necessary so that the icemaker stops automatically within 10 seconds after ice contacts the bin control thermostat...

Page 20: ...lve Float Switch Drain Check Valve Expansion Valve Compressor Hot Gas Valve High Pressure Switch Strainer Fan Drier Condenser Evaporator Access Valve Discharge Line Suction Line Water Pump Thermistor Spray Tubes Inlet Water Valve Freeze Pump Out Water Tank Access Valve Refrigeration Circuit Water Circuit Heat Exchanger ...

Page 21: ...21 B Wiring Diagram 1 KM 600MAH air cooled Transformer Output 10 5V at 115V Pressure Switch Air Cooled Model Cut out 412 21 PSIG Cut in 327 21 PSIG 0 ...

Page 22: ...2 min 100 38 70 21 80 27 90 32 min 100 38 70 21 238 16 7 259 18 2 290 20 4 80 27 254 17 9 287 20 2 319 22 4 90 32 259 18 2 310 21 8 342 24 1 PSIG kg cm2 G 100 38 266 18 7 318 22 3 372 26 2 70 21 55 3 9 56 4 0 58 4 1 80 27 56 3 9 58 4 0 60 4 2 90 32 56 4 0 59 4 1 61 4 3 PSIG kg cm2 G 100 38 57 4 0 59 4 2 62 4 4 34 35 38 2 0 4 2 2 9 3 6 2 7 2 0 3 7 33 APPROXIMATE ICE PRODUCTION PER 24 HR APPROXIMATE...

Page 23: ...te fill cycle until water enters and the float switch closes low water safety protection during initial start up and at the end of each harvest Diagnosis If the inlet water valve does not open check for no supply voltage at inlet water valve terminals bad coil or plugged screen or external filter no water flow If unit fails to start harvest check for open float switch or bad 1 minute timer in cont...

Page 24: ...d Note Normal freeze cycle will last 20 to 40 minutes depending on model and conditions Cycle times and pressures should follow performance data provided in this manual 6 Pump Out Cycle 10 20 second pump out LEDs 1 4 3 2 are on The 1st pump out occurs after the 1st freeze cycle and every 10th cycle thereafter The pump out cycle S4 dip switch 5 6 can be adjusted to occur every cycle or every 2 5 or...

Page 25: ... Tripped with bin filled with ice 1 Remove ice 2 Ambient temperature too cool 2 Increase ambient temperature 3 Set too warm 3 See II E Bin Control 4 Bulb out of position 4 Place in position 5 Bad contacts 5 Check for continuity and replace f High Pressure Control 1 Bad contacts 1 Check for continuity and replace 2 Dirty air filter or condenser 2 Clean 3 Ambient temperature too warm 3 Reduce temper...

Page 26: ...nector disconnected 1 Reconnect 2 Defective switch 2 Check and replace 3 Float does not move freely 3 Clean or replace b Control Board 1 Defective 1 See II C 4 Control Board Check Procedure 3 Compressor will not start or stops operating a Magnetic Contactor 1 Bad contacts 1 Check for continuity and replace 2 Coil winding opened 2 Replace b Start Capacitor or Run Capacitor 1 Defective 1 Replace c I...

Page 27: ...eck Valve 1 Leaking by 1 Clean or replace b Float Switch 1 Dirty or erratic operation 1 Clean or replace c Control Board 1 Defective 1 See II C 4 Control Board Check Procedure 7 Fan motor will not start or is not operating a Fan Motor 1 Motor winding opened 1 Replace 2 Bearing worn out 2 Replace 3 Wiring to fan motor 3 Check for loose connection or open and replace 4 Defective capacitor 4 Replace ...

Page 28: ...Dirty Restricted 1 Replace filter d Inlet Water Valve 1 Dirty mesh filter or orifice 1 Clean 2 Diaphragm does not close 2 Check for water leaks with icemaker off e Ambient and or water temperature 1 Too cool 1 Increase temperature f Thermistor 1 Out of position or loose attachment 1 See V I Removal and Replacement of Thermistor g Control Board 1 Harvest timer is set too short 1 Adjust longer refer...

Page 29: ...1 Check and replace f Condenser 1 Air filter or condenser clogged 1 Clean g Refrigerant Charge 1 Low charge 1 Check for leaks Recover repair evacuate and recharge h Hot Gas Valve 1 Open 1 Check and replace i Expansion Valve 1 Bulb loose 1 Secure bulb 2 Operating erratically 2 Check and replace j Compressor 1 Erratic or off 1 See chart 1 3 k Control Board 1 Float switch connection loose 1 Check and...

Page 30: ... up 2 Clean 3 Damaged 3 Replace b Water System 1 Water supply line too small requires 3 8 OD line dedicated per machine 1 Increase water line size 2 Water filter clogged or flow rate too small 2 Replace filter or install a higher flow rate filter 3 High hardness or contains impurities 3 Install a water softener or filter c Spray Guide 1 Dirty 1 Clean 5 Other Problem Possible Cause Remedy 1 Icemake...

Page 31: ...edy 3 Ice in storage bin often melts a Drain Line s 1 Plugged 1 Clean b Icemaker and Bin 1 Drains not run separately 1 Separate the drain lines c Ice Cube Guide 1 Out of position Circulated water falls into bin 1 Place in position ...

Page 32: ...ure with pressurized air for leak testing 1 Refrigerant Recovery The icemaker unit is provided with refrigerant access valves 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 2 Brazing WARNING 1 R 404A itself is not flammable at atmospheric pressure and temperatures up to 176...

Page 33: ... current refrigerants However the rubber hose and gauge manifold to be used for evacuation and refrigerant charge should be exclusively for POE oils 2 Turn on the vacuum pump Open the service manifold valves Never allow the oil in the vacuum pump to flow backwards 3 Allow the vacuum pump to pull down to a 29 9 Hg vacuum Evacuating period depends on pump capacity 4 Close the low side valve and high...

Page 34: ...or wiring 5 Remove the discharge and suction pipes 6 Remove the hold down bolts washers and rubber grommets 7 Remove the compressor Unpack the new compressor package 8 Attach the rubber grommets of the prior compressor 9 Place the compressor in position and secure it using the bolts and washers 10 Remove the drier then place the new drier in position 11 Remove the plugs from the suction discharge ...

Page 35: ...trogen gas flowing at a pressure of 3 to 4 PSIG CAUTION Always protect the valve body by using a damp cloth to prevent the valve from overheating Do not braze with the valve body exceeding 250 F 121 C 8 Use an electronic leak detector or soap bubbles to check for leaks Add a trace of refrigerant to the system if using an electronic leak detector and then raise the pressure using nitrogen gas 140 P...

Page 36: ...8 Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG CAUTION Always protect the valve body by using a damp cloth to prevent the valve from overheating Do not braze with the valve body exceeding 250 F 121 C 9 Use an electronic leak detector or soap bubbles to check for leaks Add a trace of refrigerant to the system if using an electronic leak detector and then r...

Page 37: ...ator then lift out the evaporator 7 Install the new evaporator 8 Remove the drier then place the new drier in position 9 Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG 10 Use an electronic leak detector or soap bubbles to check for leaks Add a trace of refrigerant to the system if using an electronic leak detector and then raise the pressure using nitrogen ...

Page 38: ...ape 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 the thermistor holder concave 9 Attach the new thermistor to the suction pipe in the same position as the previous thermistor Be very careful to prevent damage to the leads Secure it using t...

Page 39: ...alve 1 Turn off the power supply 2 Close the icemaker water supply line shut off valve Open the icemaker water supply line drain valve 3 Remove the front panel 4 Disconnect the valve outlet tubing by releasing the clamp 5 Loosen the fitting nut Be careful not to lose the washer 6 Disconnect the terminals from the inlet water valve 7 Remove the bracket and valve from the unit 8 Install the new valv...

Page 40: ...sembly 8 Remove the screw attaching the pump motor to the pump motor bracket 9 Remove the screws attaching the pump housing to the pump motor Remove the housing and check the impeller 10 If the impeller is defective install a new impeller 11 Install the new motor or new parts and replace the removed parts in the reverse order of which they were removed Be sure to reattach the green ground wire 12 ...

Page 41: ...quid proof gloves to prevent the cleaning and sanitizing solutions from coming into contact with skin 3 Carefully follow any instructions provided with the bottles of cleaning and sanitizing solution 4 Never run the icemaker when the water tank is empty IMPORTANT 1 The cleaning valve is used to allow solution flow to the inside of the evaporator during the cleaning and sanitizing operation It shou...

Page 42: ...e down the float switch assembly s housing shaft float and retainer rod with cleaning solution Clean the inside of the rubber boot and hose with cleaning solution Rinse the parts thoroughly with clean water d Reassemble the float switch assembly and replace it and the rubber boot in their correct positions Reconnect the vent tube and the flush tube 7 Pour the cleaning solution into the water tank ...

Page 43: ...f sanitizer to 3 gal 11 l of water 2 Remove the insulation panel 3 Pour the sanitizing solution into the water tank 4 Replace the insulation panel and the front panel in their correct positions Note Make sure that the control switch is in the WASH position and the cleaning valve is open 5 Turn on the power supply to start the sanitizing process 6 Turn off the power supply after 15 minutes 7 Remove...

Page 44: ...nser air cooled and remote air cooled models only Check the condenser once a year and clean the coil if required by using a brush or vacuum cleaner More frequent cleaning may be required depending on location C Preparing the Icemaker for Long Storage CAUTION When shutting off the icemaker for an extended time drain out all water from the water tank and remove the ice from the storage bin The stora...

Page 45: ...icemaker water supply line drain valve 2 Drain the water tank 1 Turn off the power supply and remove the front panel 2 Move the control switch to the OFF position 3 Remove the base cover 4 Remove one end of the pump tubing Drain the water tank Replace the pump tubing in its correct position See Fig 5 5 Remove all ice from the storage bin Clean the storage bin using a neutral cleaner Rinse thorough...