Motak PKM0335 Service Manual Download

Page: 85 / 132

Part Number: 000016427 Rev 00 08/2020 85

Troubleshooting

Harvest Valve

General

The harvest valve is an electrically operated valve that opens when energized, and closes

when de-energized.

Normal Operation

The valve is de-energized (closed) during the freeze cycle and energized (open) during

the harvest cycle. The valve is positioned between the receiver and the evaporator and

performs two functions:
1. Prevents refrigerant from entering the evaporator during the freeze cycle.

The harvest valve is not used during the freeze cycle. The harvest valve is de-

energized (closed) preventing refrigerant flow from the receiver into the evaporator.

2. Allows refrigerant vapor to enter the evaporator in the harvest cycle.

During the harvest cycle, the harvest valve is energized (open) allowing refrigerant

gas from the discharge line of the compressor to flow into the evaporator. The heat is

absorbed by the evaporator and allows release of the ice slab.

Exact pressures vary according to ambient temperature and ice machine model. Harvest

pressures can be found in the Cycle Time/24 Hour Ice Production/Refrigerant Pressure

Charts in this book.

Summary of Contents for PKM0335

Page 1: ...0155 PKM0335 PKM0425 PKM0535 MODELS Part Number 000016427 Rev 00 01 2021 Ice Machines Service Manual PKU0155 PKM0335 PKM0425 PKM0535 MODELS For technical Assistance please call MoTak Service 1 800 839 6754 ...

Page 2: ......

Page 3: ...t contains high voltage electricity and refrigerant charge Installation and repairs are to be performed by properly trained technicians aware of the dangers of dealing with high voltage electricity and refrigerant under pressure The technician must also be certified in proper refrigerant handling and servicing procedures All lockout and tag out procedures must be followed when working on this equi...

Page 4: ...could result in death or serious injury Caution Indicates a hazardous situation that if not avoided could result in minor or moderate injury Notice Indicates information considered important but not hazard related e g messages relating to property damage Important Indicates useful extra information about the procedure you are performing NOTE Indicates useful extra information about the procedure y...

Page 5: ...odes with the authority having jurisdiction Connect to a potable water supply only To avoid instability the installation area must be capable of supporting the combined weight of the equipment and product Additionally the equipment must be level side to side and front to back Remove all removable panels before lifting and installing and use appropriate safety equipment during installation and serv...

Page 6: ...loor immediately to prevent a slip hazard Never use sharp objects or tools to remove ice or frost Do not use mechanical devices or other means to accelerate the defrosting process When using cleaning fluids or chemicals rubber gloves and eye protection and or face shield must be worn Objects placed or dropped in the bin can affect human health and safety Locate and remove any objects immediately D...

Page 7: ...ower All utility connections and fixtures must be maintained in accordance with the authority having jurisdiction Turn off and lockout all utilities gas electric water according to approved practices during maintenance or servicing Never use a high pressure water jet for cleaning on the interior or exterior of this unit Do not use power cleaning equipment steel wool scrapers or wire brushes on sta...

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Page 9: ...ing Procedure 15 Toggle Switch Operation 15 Sanitizing Procedure 17 Remove Parts for Cleaning Descaling 18 Remedial Cleaning Procedure 22 Cleaning the Condenser Filter 23 Cleaning the Condenser 23 Removal from Service Winterization 23 Air cooled Models 23 Ice Making Sequence of Operation 24 PKM0335 PKM0425 PKM0535 24 Control Board Timers PKM0335 PKM0425 PKM0535 25 Safety Limits PKM0335 PKM0425 PKM...

Page 10: ...loat Is Down Closed 38 Ice Production Check 39 Installation Visual Inspection Checklist 40 Water System Checklist 41 Ice Formation Pattern 42 Safety Limits 43 Safety Limit 1 43 Safety Limit 2 43 Safety Limit 3 44 Safety Limit Checklist 45 Analyzing Discharge Pressure 48 Discharge Pressure High Checklist 49 Freeze Cycle Discharge Pressure Low Checklist 49 Analyzing Suction Pressure 50 Suction Press...

Page 11: ... Safety Limits 72 Safety Limit 1 72 Safety Limit 2 72 Safety Limit Stand by Mode 72 Safety Limit Checklist 75 Analyzing Discharge Pressure 78 Discharge Pressure High Checklist 79 Freeze Cycle Discharge Pressure Low Checklist 79 Analyzing Suction Pressure 80 Suction Pressure High Checklist 82 Suction Pressure Low Checklist 82 Harvest Valve 83 Harvest Valve Analysis 84 Comparing Evaporator Inlet Out...

Page 12: ...on 111 Cleanup Procedure 113 Severe System Contamination Cleanup Procedure 114 Liquid Line filter driers 115 Replacing Pressure Controls without Removing Refrigerant Charge 116 Refrigerant Amount 117 Ice Machine Normal Operation Charts 117 PKU0155 Self Contained Ice Machine 118 PKM0335 Modular Ice Machine 119 PKM0425 Modular Ice Machine 120 PKM0535 Modular Ice Machine 121 Wiring Diagram 122 PKU015...

Page 13: ...A Full Cube Air cooled Modular Model PKM0535SA Small Cube Air cooled Modular Model PKM0535FA Full Cube Air cooled Modular Model PKB0425 22 Wide Modular Bin PKB0535 30 Wide Modular Bin Ice Machine Warranty Information Warranty For warranty information visit Warranty Coverage Information Warranty Registration Warranty Verification Warranty coverage begins the day the ice machine is installed Warrant...

Page 14: ... water drain and electrical connections in the rear of the ice machine The location must not obstruct airflow through or around the ice machine condenser air flow is in the back and out the sides Refer to the chart for clearance requirements The ice machine must be protected if it will be subjected to temperatures below 32 F 0 C Failure caused by exposure to freezing temperatures is not covered by...

Page 15: ...ements Voltage The maximum allowable voltage variation is 10 of the rated voltage on the ice machine model serial number plate at start up when the electrical load is highest Fuse Circuit Breaker A separate fuse circuit breaker must be provided for each ice machine Total Circuit Ampacity The total circuit ampacity is used to help select the wire size of the electrical supply The wire size or gauge...

Page 16: ...ipment are working Check valves on sink faucets dishwashers etc If water pressure exceeds the maximum recommended pressure 80 psig 5 5 bar obtain a water pressure regulator from your Koolaire distributor Install a water shut off valve for ice making potable water Insulate water inlet lines to prevent condensation DRAIN CONNECTIONS Follow these guidelines when installing drain lines to prevent drai...

Page 17: ...Cleaner Descaler part number 9405463 and Sanitizer part number 9405653 It is a violation of Federal law to use these solutions in a manner inconsistent with their labeling Read and understand all labels printed on bottles before use DETAILED DESCALING AND SANITIZING PROCEDURE Ice machine cleaner descaler is used to remove lime scale and mineral deposits Ice machine sanitizer disinfects and removes...

Page 18: ...he toggle switch in the CLEAN or WASH position Water will flow through the water dump valve and down the drain Wait until the water trough refills then add the proper amount of ice machine cleaner descaler Model Amount of Cleaner Descaler PKU0155 2 ounces 60 ml PKM0335 PKM0425 PKM0535 5 ounces 150 ml Step 4 Wait until the cycle is complete then place the toggle switch in the off position and disco...

Page 19: ... l 2 oz 60 ml sanitizer Step 10 Use half of the sanitizer water solution to sanitize all removed components Use a spray bottle to liberally apply the solution to all surfaces of the removed parts or soak the removed parts in the sanitizer water solution Do not rinse parts after sanitizing Step 11 Use half of the sanitizer water solution to sanitize all foodzone surfaces of the ice machine and bin ...

Page 20: ...e the ice thickness and harvest float switches Pull the float switch straight down to disengage Lower the float switch until the wiring connector is visible Disconnect the wire lead from the float switch Remove the float switch from the ice machine D Remove the water distribution tube NOTE Distribution tube thumbscrews are retained to prevent loss Loosen thumbscrews but do not pull thumbscrews out...

Page 21: ... If complete removal is desired follow the ice thickness probe wire to the bulkhead grommet exit point in the back wall Pop the bulkhead grommet out of the back wall by inserting fingernails or a flat object between the back wall and the grommet and prying forward Pull the bulkhead grommet and wire forward until the connector is accessible then disconnect the wire lead from the connector Ice Thick...

Page 22: ...be ends until the tabs line up with the keyway and pull the inner tube ends outward 6 Remove the Float Valve Turn the splash shield counterclockwise one or two turns and pull the float valve forward and off the mounting bracket Disconnect the water inlet tube from the float valve at the compression fitting Remove the cap and filter screen for cleaning 7 Remove the Water Trough Apply downward press...

Page 23: ...e Bin Door A Grasp the rear of the bin door and pull bin door forward approximately 5 13 cm B Slide bin door to the rear while applying upward pressure The rear door pins will ride up into the track slot and slide backward to the stop tab C While applying pressure against the bin door pull down on the rear of each bin door track until the door pins clear the stop tabs D Slide the rear door pins of...

Page 24: ...low Move the toggle switch to the OFF position at the end of a harvest cycle after ice falls from the evaporator Move the toggle switch to the OFF position and allow the ice to melt Caution Never use anything to force ice from the evaporator Damage may result Step 2 Open the front door and move the toggle switch to the CLEAN or WASH position Wait until the water trough refills approximately 1 minu...

Page 25: ...ll remains call a service agent to clean the condenser Removal from Service Winterization AIR COOLED MODELS 1 Descale and sanitize the ice machine 2 Place the toggle switch in the off position to turn off the ice machine 3 Turn off the water supply disconnect and drain the incoming ice making water line at the rear of the ice machine and drain the water trough 4 Blow with compressed air to remove ...

Page 26: ...ll and remains on until the ice thickness float switch is satisfied Freeze Water flowing across the evaporator freezes and builds ice on the evaporator After a sheet of ice has formed the Harvest float switch signals the control board to start a harvest cycle 3 Harvest Cycle Any remaining water is purged down the drain as refrigerant gas warms the evaporator When the evaporator warms the sheet of ...

Page 27: ... times are exceeded The ice machine will continue to fill with water for up to six minutes or until the high water float opens for 5 continuous seconds The control board will energize the water inlet valve one more time 3 minutes into the freeze cycle SAFETY LIMITS PKM0335 PKM0425 PKM0535 Safety limits are stored and indicated by the control board The number of cycles required to stop the ice mach...

Page 28: ...t float switch hasn t opened for 10 continuous seconds within 4 minutes of the water inlet valve energizing the ice machine stops Safety Limit 3 is bypassed on the initial cycle manual start or after a full bin safety limit condition For all subsequent cycles the ice machine stops for 30 minutes when the water inlet valve is energized for 4 minutes and the harvest float valve didn t open Control b...

Page 29: ...ze Pressure 2b Compressor Start up Off On Off Off Off Closed Closed 5 seconds Off On Off Off On Closed Closed 5 seconds Freeze Sequence 3 Pre chill Off Off On Off On Open Closed 120 Seconds initial cycle Thereafter 30 seconds 4 Freeze On Off On Off On Open then Closed Closed then Open Until Harvest Float Switch closes for 10 continual seconds Harvest Sequence 5 Water Purge On On Off On On Closed C...

Page 30: ...s water from splashing out of the water trough 1 Inspect the bridge connecting the cubes It should be about 1 8 3 mm thick 2 If adjustment is necessary turn the ice thickness float switch clockwise to increase bridge thickness counterclockwise to decrease bridge thickness Adjust to achieve a 1 8 3 mm bridge thickness NOTE The float can be adjusted with a 3 4 wrench while the water trough is in pla...

Page 31: ...er fan motor air cooled models is supplied with power throughout the entire Freeze and Harvest Sequences The fan motor is wired through a fan cycle pressure control therefore it may cycle on and off The compressor and condenser fan motor are wired through the relay As a result any time the relay coil is energized the compressor and fan motor are supplied with power FREEZE SEQUENCE 3 Prechill The c...

Page 32: ...The momentary opening and re closing of the bin switch terminates the Harvest Sequence and returns the ice machine to the Freeze Sequence steps 3 4 AUTOMATIC SHUT OFF 6 Automatic Shut off When the storage bin is full at the end of a harvest sequence the sheet of cubes fails to clear the ice damper and will hold it down After the ice damper is held open for 7 seconds the ice machine shuts off The i...

Page 33: ...er Purge Off On Off Off Off 15 Second 2 Refrigeration Start Up Off On On On On 5 Seconds Freeze Sequence 3 Prechill Off Off On On On 30 Seconds 4 Freeze On Off On On On Until 7 Second Water Contact W Ice Thickness Probe Harvest Sequence 5 Harvest Off On On On On Bin Switch Activation Automatic Shut off 6 Automatic Shut off On Off On On On Until Bin Switch Re closes Condenser Fan Motor The fan moto...

Page 34: ...hon action stops when the water level in the sump trough drops When the siphon action stops the float valve refills the water trough to the correct level Follow steps 1 through 6 under water level check to verify the siphon system functions correctly WATER LEVEL PKU0155 Check the water level while the ice machine is in the ice mode and the water pump is running The correct water level is 1 4 6 3 m...

Page 35: ...e assembly as necessary then tighten the screws 5 Move the main ON OFF WASH toggle switch to the OFF position The water level in the trough will rise above the standpipe and run down the drain 6 Replace the siphon cap on the standpipe and verify water level and siphon action by repeating steps 3 through 5 ICE THICKNESS CHECK PKU0155 After a harvest cycle inspect the ice cubes in the ice storage bi...

Page 36: ...ts Cleaning Operation MINIMUM MAXIMUM SLAB WEIGHT PKU0155 Adjust ice thickness to meet 1 8 3 mm bridge thickness and minimum maximum weight per cycle Model Minimum Ice Weight Per Cycle Maximum Ice Weight Per Cycle PKM0335 3 4 lbs 1542 g 3 9 lbs 1769 g ...

Page 37: ...trol board for 3 seconds The control board test mode performs the following functions for a 2 minute time period Energizes all control board relays Energizes all control board lights After 2 minutes the control board will automatically initiate and complete one ice making cycle then stop Canceling a test cycle To cancel a test cycle press the test button a second time Restarting a test cycle The t...

Page 38: ...ggle switch functions properly A defective toggle switch may keep the ice machine in the OFF mode Refer to toggle switch diagnostics when Steps 1 3 test good 5 Be sure Steps 1 4 were followed thoroughly Intermittent problems are not usually related to the control board Replace control board if toggle switch operation is correct Ice Machine Does Not Cycle Into Harvest when the Harvest Float Is Down...

Page 39: ... the electrical panel to allow viewing of the control board lights Disconnect the harvest float switch wire from the control board and place a jumper on the control board harvest switch terminals Step 2 Bypass the freeze time lock in feature by moving the toggle switch Off On to cycle the ice machine on Wait until water flows over the evaporator then refer to chart Result Correction 10 seconds int...

Page 40: ...hickness Float Switch Step 2 Reapply power and move the toggle switch to Ice to bypass the freeze time lock in feature Wait until water flows over the evaporator then refer to chart Result Correction The harvest light does not come on and the ice machine stays in freeze The ice thickness float switch connectors or wiring are causing the malfunction Refer to float switch diagnostics 10 seconds into...

Page 41: ...ditions determined in Step 1 to find published 24 Hour Ice Production _____ Times are in minutes Example 1 min 15 sec converts to 1 25 min 15 seconds 60 seconds 25 minutes Weights are in pounds Example 2 lb 6 oz converts to 2 375 lb 6 oz 16 oz 375 lb 3 Perform an ice production check using the formula below 1 Freeze Time Harvest Time Total Cycle Time 2 1440 Minutes in 24 Hrs Total Cycle Time Cycle...

Page 42: ...pection Checklist Ice machine is not level Level the ice machine Condenser is dirty Clean the condenser Water filtration is plugged if used Install a new water filter Water drains are not run separately and or are not vented Run and vent drains according to the Installation Manual ...

Page 43: ...ator valve or increase the water pressure Incoming water temperature is not between 35 F 1 7 C and 90 F 32 2 C If too hot check the hot water line check valves in other store equipment Water filtration is plugged if used Install a new water filter Vent tube is not installed on water outlet drain See Installation Instructions Hoses fittings etc are leaking water Repair replace as needed Water valve...

Page 44: ...ion at the inlet The dimples in the cubes at the outlet of the evaporator may be more pronounced than those at the inlet This is normal If ice forms uniformly across the evaporator surface but does not do so in the proper amount of time this is still considered a normal ice fill pattern Extremely Thin at Evaporator Outlet There is no ice or a considerable lack of ice formation on the outlet of the...

Page 45: ...imits can be reset by cycling the toggle switch Off On and starting a new ice making cycle A safety limit is indicated by a flashing light on the control board SAFETY LIMIT 1 If the freeze time reaches 35 minutes the control board automatically initiates a harvest cycle After 3 consecutive 35 minute cycles control board light SL 1 light will flash on off at 1 second intervals If 6 consecutive 35 m...

Page 46: ...0 consecutive failures occur the ice machine stops and the SL 1 SL 2 lights flash on off at 1 second intervals SL 1 SL 2 will flash 3 times on start up and automatically erase after 100 normal cycles Determining Which Safety Limit Stopped the Ice Machine 1 Cycle the toggle switch Off 2 Cycle the toggle switch On to start ice making 3 Watch the safety limit lights One will flash corresponding to sa...

Page 47: ...lation Visual Inspection Checklist on page 42 Water System Float switch or water escaping water trough Low water pressure 20 psig min High water pressure 80 psig max High water temperature 90 F 32 2 C max Clogged water distribution tube Dirty defective water inlet valve Defective water pump Electrical System Harvest cycle not initiated electrically Contactor not energizing Compressor electrically ...

Page 48: ...00 Consecutive harvest cycles Possible Cause Checklist Improper installation Refer to Installation Visual Inspection Checklist on page 42 Water System Water area evaporator dirty Dirty defective water dump valve Vent tube not installed on water outlet drain Water freezing behind evaporator Plastic extrusions and gaskets not securely mounted to the evaporator Electrical System Bin switch defective ...

Page 49: ...ble Cause Checklist Improper installation Refer to Installation Visual Inspection Checklist on page 42 Water System Water dump valve Harvest float valve dirty or defective Low water pressure 20 psig min Dirty defective water filter when used Loss of water from sump area Dirty defective water inlet valve Electrical System Water inlet valve coil defective Harvest float valve defective ...

Page 50: ...cle ______ 3 Perform an actual discharge pressure check Freeze Cycle PSIG Harvest Cycle PSIG Beginning of Cycle ______________________ ______________________ Middle of Cycle ______________________ ______________________ End of Cycle ______________________ ______________________ 4 Compare the actual discharge pressure Step 3 with the published discharge pressure Step 2 The discharge pressure is nor...

Page 51: ...or Improper Refrigerant Charge Overcharged Non condensible in system Wrong type of refrigerant Other Non OEM components in system High side refrigerant lines component restricted before mid condenser FREEZE CYCLE DISCHARGE PRESSURE LOW CHECKLIST Improper Installation Refer to Installation Visual Inspection Checklist on page 42 Improper Refrigerant Charge Undercharged Wrong type of refrigerant Othe...

Page 52: ... and water temperature entering the ice machine changes These variables also determine the freeze cycle times To analyze and identify the proper suction pressure drop throughout the freeze cycle compare the published suction pressure to the published freeze cycle time NOTE Analyze discharge pressure before analyzing suction pressure High or low discharge pressure may be causing high or low suction...

Page 53: ... Published Freeze Cycle Suction Pressure psig In the example the proper suction pressure should be approximately 39 psig at 7 minutes 30 psig at 12 minutes etc 3 Perform an actual suction pressure check at the beginning middle and end of the freeze cycle Note the times at which the readings are taken Example Manifold gauges were connected to the example ice machine and suction pressure readings ta...

Page 54: ...ding check bulb mounting Defective compressor SUCTION PRESSURE LOW CHECKLIST Improper Installation Refer to Installation Visual Inspection Checklist on page 42 Discharge Pressure Discharge pressure is too low and is affecting suction pressure refer to Freeze Cycle Discharge Pressure Low Checklist on page 51 Improper Refrigerant Charge Undercharged Wrong type of refrigerant Other Non OEM components...

Page 55: ...he freeze cycle The harvest valve is not used during the freeze cycle The harvest valve is de energized closed preventing refrigerant flow from the discharge line into the evaporator 2 Allows refrigerant vapor to enter the evaporator in the harvest cycle During the harvest cycle the harvest valve is energized open allowing refrigerant gas from the discharge line of the compressor to flow into the ...

Page 56: ... of leakage increases the length of the freeze cycle increases and the amount of ice at the outlet of the evaporator decreases Refer to the Parts Manual for proper valve application If replacement is necessary use only original replacement parts Use the following procedure and table to help determine if a harvest valve is remaining partially open during the freeze cycle 1 Wait five minutes into th...

Page 57: ...roaches the temperature of a hot compressor discharge line Hot Hot This is an indication something is wrong as the harvest valve inlet did not cool down during the freeze cycle If the compressor dome is also entirely hot the problem is not a harvest valve leaking but rather something causing the compressor and the entire ice machine to get hot Both the inlet of the harvest valve and the compressor...

Page 58: ...hese temperatures must be within 7 F 4 C of each other Use this procedure to document freeze cycle inlet and outlet temperatures 1 Use a quality temperature meter capable of taking temperature readings on curved copper lines 2 Attach the temperature meter sensing device to the copper lines entering and leaving the evaporator Important Do not simply insert the sensing device under the insulation It...

Page 59: ...eeze cycle discharge line temperature will be higher than 150 F 66 C on a normally operating ice machine PROCEDURE Connect a temperature probe on the compressor discharge line within 6 15 cm of the compressor Observe the discharge line temperature for the last three minutes of the freeze cycle and record the maximum discharge line temperature Discharge Line Temperature Above 150 F 66 C at End of F...

Page 60: ... Enter check marks in the boxes Each time the actual findings of an item in the Operational Analysis column matches the published findings on the table enter a check mark Example Freeze cycle suction pressure is determined to be low Enter a check mark in the low box Perform the procedures and check all information listed Each item in this column has supporting reference material While analyzing ea...

Page 61: ...n the total charge of refrigerant If the problem is corrected the ice machine is low on charge Find the refrigerant leak The ice machine must operate with the nameplate charge If the leak cannot be found proper refrigerant procedures must still be followed Change the liquid line drier evacuate the system and weigh in the proper charge If the problem is not corrected by adding charge the expansion ...

Page 62: ...o ice formation on entire evaporator Ice formation extremely thin on outlet of evaporator or No ice formation on entire evaporator Ice formation is normal or Ice formation is extremely thin on the bottom of evaporator or No ice formation on evaporator Ice formation is normal or No ice formation on entire evaporator Safety Limits Refer to Analyzing Safety Limits to eliminate all non refrigeration p...

Page 63: ...s HOT The harvest valve inlet is COOL and The compressor discharge line is HOT The harvest valve inlet is COOL and The compressor discharge line is COOL The harvest valve inlet is COOL and The compressor discharge line is HOT Discharge Line Temp Record freeze cycle discharge line temp at the end of freeze cycle Discharge line temp 150 F 66 C or higher at the end of freeze cycle Discharge line temp...

Page 64: ...64 Part Number 000016427 Rev 00 08 2020 Troubleshooting THIS PAGE INTENTIONALLY LEFT BLANK ...

Page 65: ...s closed 2 Verify control board fuse is okay 3 If the bin switch light functions the fuse is okay 4 Verify the bin switch functions properly A defective bin switch can falsely indicate a full bin of ice 5 Verify ON OFF WASH toggle switch functions properly A defective toggle switch may keep the ice machine in the OFF mode 6 Verify low DC voltage is properly grounded Loose DC wire connections may i...

Page 66: ...ICKNESS PROBE PROBE CONNECTION GROUND JUMPER WIRE BIN SWITCH LIGHT GREEN HARVEST LIGHT RED SV1592i Step 2 Jumper wire connected from probe to ground Monitoring Harvest Light Correction The harvest light comes on and 6 10 seconds later ice machine cycles from freeze to harvest The ice thickness control circuitry is functioning properly Do not change any parts The harvest light comes on but the ice ...

Page 67: ...tep 3 Jumper wire connected from control board terminal to ground Monitoring Harvest Light Correction The harvest light comes on and 6 10 seconds later ice machine cycles from freeze to harvest The ice thickness probe is causing the malfunction The harvest light comes on but the ice machine stays in the freeze sequence The control circuitry is functioning properly The ice machine is in a six minut...

Page 68: ...ickness probe from the control board terminal ICE THICKNESS PROBE DISCONNECT PROBE WIRE BIN SWITCH LIGHT GREEN HARVEST LIGHT RED SV1592J_2 Step 2 Disconnect probe from control board terminal Monitoring Harvest Light Correction The harvest light stays off and the ice machine remains in the freeze sequence The ice thickness probe is causing the malfunction Verify that the ice thickness probe is adju...

Page 69: ...c converts to 1 25 min 15 seconds 60 seconds 25 minutes Weights are in pounds Example 2 lb 6 oz converts to 2 375 lb 6 oz 16 oz 375 lb 3 Perform an ice production check using the formula below 1 Freeze Time Harvest Time Total Cycle Time 2 1440 Minutes in 24 Hrs Total Cycle Time Cycles per Day 3 x Weight of One Harvest Cycles per Day Actual 24 Hour Production Weighing the ice is the only 100 accura...

Page 70: ...refrigeration system component malfunction Example A water dump valve leaking during the freeze cycle a system low on charge and a starving TXV have similar symptoms Water system problems must be identified and eliminated prior to replacing refrigeration components Water area evaporator is dirty Clean as needed Water inlet pressure not between 20 and 80 psig 1 5 bar 138 552 kPa Install a water reg...

Page 71: ...Repair replace as needed Water float valve is stuck open or closed Clean replace as needed Water is spraying out of the sump trough area Stop the water spray Uneven water flow across the evaporator Clean the ice machine Water is freezing behind the evaporator Correct the water flow Plastic extrusions and gaskets are not secured to the evaporator Remount replace as needed ...

Page 72: ...aking out the overflow pipe a faulty water float valve a low refrigerant charge etc OUTLET INLET OUTLET INLET K0170 K0270 Examples of Evaporator Tubing Routing Normal Ice Formation Ice forms across the entire evaporator surface At the beginning of the Freeze cycle it may appear that more ice is forming on the inlet of the evaporator than at the outlet At the end of the Freeze cycle ice formation a...

Page 73: ...e is no ice or a considerable lack of ice formation at the inlet of the evaporator Examples The ice at the outlet of the evaporator reaches the correct thickness but there is no ice formation at all at the inlet of the evaporator Possible cause Insufficient water flow flooding TXV etc Spotty Ice Formation There are small sections on the evaporator where there is no ice formation This could be a si...

Page 74: ...n to standard safety controls the control board has two built in safety limit controls which protect the ice machine from major component failures SAFETY LIMIT 1 If the freeze time reaches 60 minutes the control board automatically initiates a harvest cycle 3 cycles outside the time limit 1 hour Stand by Mode SAFETY LIMIT 2 If the harvest time reaches 3 5 minutes the control board automatically re...

Page 75: ...estart and run until a safety limit is exceeded again Safety Limit Notes A safety limit indication is completed before the water pump starts Water contacting the ice thickness probe in the freeze cycle will cause the harvest light to flash Do not mistake a harvest light flashing in the freeze cycle with a safety limit indication A continuous run of 100 harvests automatically erases the safety limi...

Page 76: ...e safety limits are designed to stop the ice machine prior to major component failures most often a minor problem or something external to the ice machine This may be difficult to diagnose as many external problems occur intermittently Example An ice machine stops intermittently on safety limit 1 long freeze times The problem could be a low ambient temperature at night a water pressure drop the wa...

Page 77: ...efer to Installation and Visual Inspection Checklist on page 70 Water System Water Level set too high water escaping through over flow tube Low water pressure 20 psig min High water pressure 80 psig max High water temperature 90 F 32 2 C max Clogged water distribution tube Dirty defective float valve Defective water pump Electrical System Ice thickness probe out of adjustment Harvest cycle not ini...

Page 78: ...flow Condenser discharge air re circulation Dirty condenser fins Non OEM components Improper refrigerant charge Defective compressor TXV starving or flooding check bulb mounting Non condensible in refrigeration system Plugged or restricted high side refrigerant lines or component Defective harvest valve ...

Page 79: ...led on water outlet drain Water freezing behind evaporator Plastic extrusions and gaskets not securely mounted to the evaporator Low water pressure 20 psig min Loss of water from sump area Clogged water distribution tube Dirty defective float valve Defective water pump Electrical System Ice thickness probe out of adjustment Ice thickness probe dirty Bin switch defective Premature harvest Refrigera...

Page 80: ...le ______ 3 Perform an actual discharge pressure check Freeze Cycle PSIG Harvest Cycle PSIG Beginning of Cycle ______________________ ______________________ Middle of Cycle ______________________ ______________________ End of Cycle ______________________ ______________________ 4 Compare the actual discharge pressure step 3 with the published discharge pressure step 2 The discharge pressure is norm...

Page 81: ...n motor Improper Refrigerant Charge Overcharged Non condensible in system Wrong type of refrigerant Other Non OEM components in system High side refrigerant lines component Restricted before mid condenser FREEZE CYCLE DISCHARGE PRESSURE LOW CHECKLIST Improper Installation Refer to Installation and Visual Inspection Checklist on page 70 Improper Refrigerant Charge Undercharged Wrong type of refrige...

Page 82: ... and water temperature entering the ice machine changes These variables also determine the freeze cycle times To analyze and identify the proper suction pressure drop throughout the freeze cycle compare the published suction pressure to the published freeze cycle time NOTE Analyze discharge pressure before analyzing suction pressure High or low discharge pressure may be causing high or low suction...

Page 83: ...Published Freeze Cycle Suction Pressure psig In the example the proper suction pressure should be approximately 39 psig at 7 minutes 30 psig at 12 minutes etc 3 Perform an actual suction pressure check at the beginning middle and end of the freeze cycle Note the times at which the readings are taken Example Manifold gauge set was connected to the example ice machine and suction pressure readings t...

Page 84: ...pressor SUCTION PRESSURE LOW CHECKLIST Improper Installation Refer to Installation and Visual Inspection Checklist on page 70 Discharge Pressure Discharge pressure is too low and is affecting suction pressure refer to Freeze Cycle Discharge Pressure Low Checklist on page 81 Improper Refrigerant Charge Undercharged Wrong type of refrigerant Other Non OEM components in system Improper water supply o...

Page 85: ...eze cycle The harvest valve is not used during the freeze cycle The harvest valve is de energized closed preventing refrigerant flow from the receiver into the evaporator 2 Allows refrigerant vapor to enter the evaporator in the harvest cycle During the harvest cycle the harvest valve is energized open allowing refrigerant gas from the discharge line of the compressor to flow into the evaporator T...

Page 86: ... seat VALVE REMAINS OPEN IN THE FREEZE CYCLE Symptoms of a harvest valve remaining partially open during the freeze cycle can be similar to symptoms of an expansion valve float valve or compressor problem Symptoms are dependent on the amount of leakage in the freeze cycle A small amount of leakage will cause increased freeze times and an ice fill pattern that is Thin at the Outlet but fills in at ...

Page 87: ...valve outlet or across the harvest valve itself will not work for this comparison The harvest valve outlet is on the suction side cool refrigerant It may be cool enough to touch even if the valve is leaking 3 Feel the compressor discharge line nWarning The inlet of the harvest valve and the compressor discharge line could be hot enough to burn your hand Just touch them momentarily 4 Compare the te...

Page 88: ...roaches the temperature of a hot compressor discharge line Hot Hot This is an indication something is wrong as the harvest valve inlet did not cool down during the freeze cycle If the compressor dome is also entirely hot the problem is not a harvest valve leaking but rather something causing the compressor and the entire ice machine to get hot Both the inlet of the harvest valve and the compressor...

Page 89: ...e These temperatures must be within 7 F 4 C of each other Use this procedure to document freeze cycle inlet and outlet temperatures 1 Use a quality temperature meter capable of taking temperature readings on curved copper lines 2 Attach the temperature meter sensing device to the copper lines entering and leaving the evaporator Important Do not simply insert the sensing device under the insulation...

Page 90: ...cycle discharge line temperature will be higher than 150 F 66 C on a normally operating ice machine PROCEDURE Connect a temperature probe on the compressor discharge line within 6 15 2 cm of the compressor Observe the discharge line temperature for the last three minutes of the freeze cycle and record the maximum discharge line temperature Discharge Line Temperature Above 150 F 66 C at End of Free...

Page 91: ...mn Enter check marks in the boxes Each time the actual findings of an item in the Operational Analysis column matches the published findings on the table enter a check mark Example Freeze cycle suction pressure is determined to be low Enter a check mark in the low box Perform the procedures and check all information listed Each item in this column has supporting reference material While analyzing ...

Page 92: ...n the total charge of refrigerant If the problem is corrected the ice machine is low on charge Find the refrigerant leak The ice machine must operate with the nameplate charge If the leak cannot be found proper refrigerant procedures must still be followed Change the liquid line drier evacuate the system and weigh in the proper charge If the problem is not corrected by adding charge the expansion ...

Page 93: ... formation on the entire evaporator Ice formation extremely thin on top of the evaporator or No ice formation on entire evaporator Ice formation is normal or Ice formation is extremely thin on the bottom of evaporator or no ice formation on evaporator Ice formation is normal or No ice formation on entire evaporator Safety Limits Refer to Analyzing Safety Limits to eliminate all non refrigeration p...

Page 94: ... HOT The harvest valve inlet is COOL and The compressor discharge line is HOT The harvest valve inlet is COOL and The compressor discharge line is COOL The harvest valve inlet is COOL and The compressor discharge line is HOT Discharge Line Temp Record freeze cycle discharge line temp at the end of freeze cycle Discharge line temp 150 F 66 C or higher at the end of freeze cycle Discharge line temp ...

Page 95: ...r filtration is poor Replace the filter Water softener is working improperly if applicable Repair the water softener Poor incoming water quality Contact a qualified company to test the quality of the incoming water and make appropriate filter recommendations Water escaping from sump during freeze cycle Check standpipe and drain Check for water tracking out of water circuit ...

Page 96: ...ust not exceed 120 F 39 C Water inlet valve filter screen is dirty Remove the water inlet valve and clean the filter screen Water inlet valve stuck open or leaking Turn off ice machine if water continues to enter ice machine verify water pressure is ok then replace water inlet valve Water inlet valve is not working Water inlet valve must be replaced Refrigeration problem Refer to refrigeration dia...

Page 97: ...r Excessive mineral buildup Clean and sanitize the ice machine Ambient temperature is too high or low Ambient temperature must be between 50 F and 110 F 10 C and 43 C Compressor relay inoperable No voltage to coil or coil defective Defective contacts Compressor off on overload Condenser fan motor defective Incorrect flow to water cooled condenser Ambient temperature too high Condenser blocked Faul...

Page 98: ...98 Part Number 000016427 Rev 00 08 2020 Troubleshooting THIS PAGE INTENTIONALLY LEFT BLANK ...

Page 99: ...ol board at all times Removing the control board fuse or cycling the toggle switch Off On will not remove the power supplied to the control board Check Procedure 1 If the curtain light is on with the water curtain closed the fuse is good nWarning Disconnect electrical power to the entire ice machine before proceeding 2 Remove the fuse Check the resistance across the fuse with an ohmmeter Reading R...

Page 100: ...operating position the bin switch closes and the ice machine restarts Important The water curtain must be installed bin switch closed to start ice making Check Procedure 1 Cycle the toggle switch OFF 2 Watch the curtain light on the control board 3 Move the water curtain upward toward the evaporator The bin switch must close The curtain light on indicates the bin switch has closed properly 4 Move ...

Page 101: ...ure The ice machine uses two float switches Ice Thickness Float Indicates the water level has been reached Harvest Float Indicates a harvest cycle needs to be initiated Initial testing can be performed by viewing the control board light s while raising and lowering the float The corresponding control board light must turn on and off when the float is raised and lowered Harvest Float Switch A The l...

Page 102: ...er lead to each float switch wire 3 Place the float in the down position The float switch must be closed 4 Place the float in the up position The float switch must be open 5 If the float tests good ohm the interconnecting wires to the control board and inspect connectors NOTE Make adjustments with the ice machine in the off position Making adjustments during the freeze cycle may produce an initial...

Page 103: ... the wires from the compressor terminals 2 The resistance values between C and S and between C and R when added together should equal the resistance value between S and R 3 If the overload is open there will be a resistance reading between S and R and open readings between C and S and between C and R Allow the compressor to cool then check the readings again Check Motor Windings to Ground Check co...

Page 104: ...meplate voltage PTCR The PTCR allows current to flow through the start winding at compressor startup Current flow heats the ceramic discs in the PTCR The electrical resistance increases with temperature and stops all except a trickle of current flow through the start winding The small flow of current keeps the PTCR hot 260 F 127 C and the start winding out of the circuit The PTCR must be cooled be...

Page 105: ...rature 3 Remove the PTCR from the ice machine 4 Measure the resistance of the PTCR as shown The resistance reading must be between Model Ohm Value Amp PKM0335 PKM0425 PKM0535 10 5 to 19 5 12 Two Terminal PTCR Fan Cycle Control Function Cycles the fan motor on and off to maintain proper operating discharge pressure The fan cycle control closes on an increase and opens on a decrease in discharge pre...

Page 106: ...grounded and fan spins freely Connect manifold gauge to ice machine Hook voltmeter in parallel across the fan cycle control leaving wires attached Reconnect electrical power to the ice machine and Cycle the toggle switch On Wait until water flows over the evaporator then refer to chart below System Pressure Reading Should Be Fan Should Be above cut in 0 volts running below cut out line voltage off...

Page 107: ...rallel across the HPCO leaving wires attached 4 On water cooled models close the water service valve to the water condenser inlet On self contained air cooled models disconnect the fan motor 5 Move toggle switch to ON 6 No water or air flowing through the condenser will cause the HPCO control to open because of excessive pressure Watch the pressure gauge and record the cut out pressure nWarning If...

Page 108: ...ervice shop Reclaim To reprocess refrigerant to new product specifications see below by means which may include distillation A chemical analysis of the refrigerant is required after processing to be sure that product specifications are met This term usually implies the use of processes and procedures available only at a reprocessing or manufacturing facility Chemical analysis is the key requiremen...

Page 109: ...rom the use of contaminated recovered or recycled refrigerant is the sole responsibility of the servicing company 1 New Refrigerant Must be of original nameplate type 2 Reclaimed Refrigerant Must be of original nameplate type Must meet ARI Standard 700 latest edition specifications 3 Recovered or Recycled Refrigerant Must be recovered or recycled in accordance with current local state and federal ...

Page 110: ...ystem was cleaned evacuated and recharged properly following failure s Whether the system has been contaminated by this failure Compressor motor burnouts and improper past service prevent refrigerant re use Refer to Determining Severity of Contamination on page 113 to test for contamination 5 Substitute or Alternative Refrigerant Must use only approved alternative refrigerants Must follow publishe...

Page 111: ...prevent voiding the warranty CONNECTIONS 1 Suction side of the compressor through the suction service valve 2 Discharge side of the compressor through the discharge service valve 3 Liquid side through the liquid line drier SELF CONTAINED RECOVERY EVACUATION 1 Cycle the toggle switch Off 2 Install manifold gauge scale and recovery unit or two stage vacuum pump and open high low and charging ports 3...

Page 112: ...ilter driers without an access port must be replaced with the current OEM part before recharging the ice machine All Liquid refrigerant must be added through the liquid line drier access port 5 Let the system settle for 2 to 3 minutes 6 Cycle the toggle switch On NOTE Manifold gauge set must be removed properly to ensure that no refrigerant contamination or loss occurs 7 Make sure that all of the ...

Page 113: ...ther moisture or residue from compressor burnout entering the refrigeration system Inspection of the refrigerant usually provides the first indication of system contamination Obvious moisture or an acrid odor in the refrigerant indicates contamination If harmful levels of contamination are suspected perform the following procedure 1 Remove the refrigerant charge from the ice machine 2 Remove the c...

Page 114: ...st kit and or acid oil test shows contamination No burnout deposits in open compressor lines Mild contamination cleanup procedure Mild Compressor Burnout symptoms Oil appears clean but smells acrid Refrigeration test kit or acid oil test shows harmful acid content No burnout deposits in open compressor lines Mild contamination cleanup procedure Severe Compressor Burnout symptoms Oil is discolored ...

Page 115: ... except replace the evacuation step with the following A Pull vacuum to 1000 microns Break the vacuum with dry nitrogen and sweep the system Pressurize to a minimum of 5 psig B Pull vacuum to 500 microns Break the vacuum with dry nitrogen and sweep the system Pressurize to a minimum of 5 psig C Change the vacuum pump oil D Pull vacuum to 500 microns Run the vacuum pump for 1 2 hour on self contain...

Page 116: ...nt of compressor 7 Install an access valve at the inlet of the suction line drier 8 Install a new liquid line drier 9 Follow the normal evacuation procedure except replace the evacuation step with the following A Pull vacuum to 1000 microns Break the vacuum with dry nitrogen and sweep the system Pressurize to a minimum of 5 psig B Change the vacuum pump oil C Pull vacuum to 500 microns Break the v...

Page 117: ...id line drier if necessary 13 Follow normal evacuation procedures LIQUID LINE FILTER DRIERS The filter driers used on these ice machines have an access fitting for charging with refrigerant The drier also has dirt retaining filtration with fiberglass filters on both the inlet and outlet ends This is very important because ice machines have a back flushing action that takes place during every Harve...

Page 118: ...ubing as far from the pressure control as feasible See the figure on next page Clamp down on the tubing until the pinch off is complete nWarning Do not unsolder a defective component Cut it out of the system Do not remove the pinch off tool until the new component is securely in place 3 Cut the tubing of the defective component with a small tubing cutter 4 Solder the replacement component in place...

Page 119: ...le times can be 1 2 minutes faster depending on model and ambient temperature Ice production checks that are within 10 of the chart are considered normal This is due to variances in water and air temperature Actual temperatures will seldom match the chart exactly Refer to Operational Analysis Chart for the list of data that must be collected for refrigeration diagnostics Zero out manifold gauge se...

Page 120: ...s 24 HOUR ICE PRODUCTION Air Temp Entering Condenser F C Water Temperature F C 50 10 70 21 90 32 70 21 165 155 125 80 27 155 145 115 90 32 140 125 110 100 38 120 105 90 110 43 95 80 65 Based on average ice slab weight of 2 44 2 75 lb 1 11 1 25 kg Regular cube derate is 7 OPERATING PRESSURES Air Temp Entering Condenser F C Freeze Cycle Harvest Cycle Discharge Pressure PSIG Suction Pressure PSIG Dis...

Page 121: ...Air Temp Entering Condenser F C Water Temperature F C 50 10 70 21 90 32 70 21 330 280 250 80 27 285 250 230 90 32 260 230 210 100 38 235 215 195 110 43 210 200 180 Based on average ice slab weight of 3 40 3 90 lb 1 54 1 77 kg 230 50 1 production is approximately 12 lower than 230 60 1 OPERATING PRESSURES Air Temp Entering Condenser F C Freeze Cycle Harvest Cycle Discharge Pressure PSIG Suction Pre...

Page 122: ... Air Temp Entering Condenser F C Water Temperature F C 50 10 70 21 90 32 70 21 370 350 325 80 27 340 320 290 90 32 315 305 270 100 38 285 265 250 110 43 255 240 225 Based on average ice slab weight of 3 40 3 90 lb 1 54 1 77 kg 230 50 1 production is approximately 12 lower than 230 60 1 OPERATING PRESSURES Air Temp Entering Condenser F C Freeze Cycle Harvest Cycle Discharge Pressure PSIG Suction Pr...

Page 123: ...Air Temp Entering Condenser F C Water Temperature F C 50 10 70 21 90 32 70 21 515 425 400 80 27 450 420 375 90 32 420 400 350 100 38 385 350 325 110 43 365 325 300 Based on average ice slab weight of 4 125 4 75 lb 1 87 2 15 kg 230 50 1 production is approximately 12 lower than 230 60 1 OPERATING PRESSURES Air Temp Entering Condenser F C Freeze Cycle Harvest Cycle Discharge Pressure PSIG Suction Pr...

Page 124: ...Legend The following symbols are used on all of the wiring diagrams Internal Compressor Overload Some models have external compressor overloads Fan Motor Run Capacitor Some models do not incorporate fan motor run capacitor Wire Number Designation The number is marked at each end of the wire Multi pin Connection Electrical Box Side Compressor Compartment Side ...

Page 125: ...5 10 11 C S R 11 10 PKU0155 1 Control Board 2 Fuse 3 Transformer 4 On Off Clean Switch 5 Bin Switch 6 Bin Thermostat 7 High Pressure Cut Out 10 Harvest Solenoid Valve 18 Contactor Coil 19 Contactor Contacts 20 Compressor 21 Compressor Relay 23 Compressor Start Capacitor 25 Compressor Overload 27 Condenser Fan Motor 29 Fan Cycle Control 30 Water Pump 32 Ice Thickness Control ...

Page 126: ...nt 3 Bin Switch 5 Compressor 7 Compressor Overload 11 Compressor Run Capacitor 14 Condenser Fan Motor 15 Condenser Fan Motor Run Capacitor 17 Contactor Coil 18 Contactor Contacts 19 Control Board 25 Fan Cycle Control 26 Harvest Float Switch 27 Water Level Float Switch 28 Fuse 31 High Pressure Cutout 40 On Off Clean Switch 41 See Control Board Schematic For Detail 42 Solenoid Valve Harvest 54 Trans...

Page 127: ...p Relay 2 LED Compressor Relay 3 LED Water Dump Valve Relay 4 LED Harvest Solenoid Valve 5 LED Clean 6 Thermistor 7 Thermistor 8 Thermistor 9 LED Water Fill Valve 10 LED Harvest Float 11 LED Water Level Float 12 LED Bin Switch 13 LED Safety Limit 2 14 LED Safety Limit 1 15 LED Harvest 16 LED Test Mode 17 Fuse 18 Motor Connector 19 EC Fan Motor Connector 20 Bin Switch Connector 21 Float Switch Wate...

Page 128: ... CONTROL BOARD SCHEMATIC PKU0155 1 2 3 4 5 6 7 8 Number Component 1 Ice Thickness Probe Connector 2 DC Low Voltage Electrical Connector 3 Bin Switch Light 4 Harvest Light 5 Transformer 6 Component Relays 7 AC Line Voltage Electrical Connector 8 10 Amp Fuse ...

Page 129: ...hematic PKU0155 PKM0335 PKM0425 PKM0535 X X 1 2 3 4 5 8 9 6 7 Number Component 1 Compressor 2 Condenser Air or Water cooled 3 Receiver Water Cooled Only 4 Liquid Line Filter Drier 5 Heat Exchanger 6 TXV Thermostatic Expansion Valve 7 Evaporator 8 Strainer 9 Harvest Solenoid Valve ...

Page 130: ...130 Part Number 000016427 Rev 00 08 2020 Specifications THIS PAGE INTENTIONALLY LEFT BLANK ...

Page 131: ......

Page 132: ...Katom 305 Katom Drive Kodak Tennessee 37764 Part Number 000016427 Rev 00 08 2020 ...

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