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Safety Notices As you work on a Q Model Ice Machine, be sure to pay close attention to the safety notices in this handbook. Disregarding the notices may lead to serious injury and/or damage to the ice machine. Throughout this handbook, you will see the following types of safety notices: Warning Text in a Warning box alerts you to a potential...
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! Caution Proper installation, care and maintenance are essential for maximum ice production and trouble free operation of your Manitowoc Ice Machine. If you encounter problems not covered by this manual, do not proceed; contact Manitowoc Ice, Inc. We will be happy to provide assistance.
Table of Contents General Information How to Read a Model Number ......1 Ice Cube Sizes ............1 Model/Serial Number Location ......2 Ice Machine Warranty Information ......2 Owner Warranty Registration Card ....2 Warranty Coverage .......... 3 Installation Location of Ice Machine ........
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Q1300/Q1800 - Self Contained - 3 Phase With Terminal Board......35 Q1300/Q1600/Q1800 - Self Contained - 3 Phase Without Terminal Board....36 Q450/Q600/Q800/Q1000 - Remote - 1 Phase With Terminal Board......37 Q450/Q600/Q800/Q1000 - Remote - 1 Phase Without Terminal Board....38 Q800/Q1000 -Remote - 3 Phase With Terminal Board......
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Main Fuse............46 Bin Switch............47 Water Curtain Removal Notes......49 ICE/OFF/CLEAN Toggle Switch..... 50 Ice Thickness Probe (Harvest Initiation)..51 Ice Thickness Probe Diagnostics ....53 Diagnosing Ice Thickness Control Circuitry..54 Water Level Control Circuitry......56 Diagnosing an Ice Machine Head Section that Will Not Run..........
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Cycle Times/24-Hour Ice Production/ Refrigerant Pressure Charts......119 Q200 Series Self-Contained Air-Cooled ......120 Self-Contained Water-Cooled....121 Q280 Series Self-Contained Air-Cooled ......122 Self-Contained Water-Cooled....123 Q320 Series Self-Contained Air-Cooled ......124 Self-Contained Water-Cooled....125 Q370 Series Self-Contained Air-Cooled ......126 Self-Contained Water-Cooled....
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Refrigerant Recovery/Evacuation...... 148 Normal Self-Contained Model Procedures ... 148 Normal Remote Model Procedures ....152 System Contamination Clean-Up ...... 157 General............157 Determining Severity Of Contamination ..157 Cleanup Procedure ........159 Replacing Pressure Controls Without Removing Refrigerant Charge ........162 Filter-Driers...........
General Information HOW TO READ A MODEL NUMBER # CUBE SIZE CONDENSER TYPE REGULAR AIR-COOLED REGULAR WATER-COOLED DICE AIR-COOLED 9 REMOTE AIR-COOLED DICE WATER-COOLED HALF-DICE AIR-COOLED HALF-DICE WATER-COOLED Q R 0450 A ICE MACHINE ICE MACHINE MODEL SERIES ICE CUBE SIZE CONDENSER TYPE R REGULAR A SELF-CONTAINED AIR-COOLED...
REGISTRATION CARD as soon as possible to validate the installation date. If the OWNER WARRANTY REGISTRATION CARD is not returned, Manitowoc will use the date of sale to the Manitowoc Distributor as the first day of warranty coverage for your new ice machine.
The following Warranty outline is provided for your convenience. For a detailed explanation, read the warranty bond shipped with each product. Contact your local Manitowoc representative or Manitowoc Ice, Inc. if you need further warranty information. Important This product is intended exclusively for commercial application.
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AUTHORIZED WARRANTY SERVICE To comply with the provisions of the warranty, a refrigeration service company qualified and authorized by your Manitowoc Distributor, or a Contracted Service Representative must perform the warranty repair. NOTE: If the dealer you purchased the ice machine...
Installation LOCATION OF ICE MACHINE The location selected for the ice machine head section must meet the following criteria. If any of these criteria are not met, select another location. • The location must be free of airborne and other contaminants.
STACKING TWO ICE MACHINES ON A SINGLE STORAGE BIN A stacking kit is required for stacking two ice machines. Installation instructions are supplied with the stacking kit. Stacked Stacked Q450/Q600/ Self-Contained Water-Cooled and Q800/Q1000 Air-Cooled Remote Top/Sides 16" (40.64 cm) 5"...
Calculating Remote Condenser Installation Distances LINE SET LENGTH The maximum length is 100' (30.5 m). The ice machine compressor must have the proper oil return. The receiver is designed to hold a charge sufficient to operate the ice machine in ambient temperatures between -20°F (-28.9°C) and 120°F (49°C), with line set lengths of up to 100' (30.5 m).
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CALCULATED LINE SET DISTANCE The maximum calculated distance is 150' (45.7 m). Line set rises, drops, horizontal runs (or combinations of these) in excess of the stated maximums will exceed compressor start-up and design limits. This will cause poor oil return to the compressor. Make the following calculations to make sure the line set layout is within specifications.
Removal from Service/Winterization GENERAL Special precautions must be taken if the ice machine is to be removed from service for an extended period of time or exposed to ambient temperatures of 32°F (0°C) or below. ! Caution If water is allowed to remain in the ice machine in freezing temperatures, severe damage to some components could result.
3. Insert a large screwdriver between the bottom spring coils of the water regulating valve. Pry upward to open the valve. SV1624 4. Hold the valve open and blow compressed air through the condenser until no water remains. REMOTE ICE MACHINES 1.
Ice Making Sequence of Operation SELF-CONTAINED AIR- AND WATER-COOLED Initial Start-Up or Start-Up After Automatic Shut-Off 1. Water Purge Before the compressor starts, the water pump and water dump solenoid are energized for 45 seconds to purge the ice machine of old water. This ensures that the ice-making cycle starts with fresh water.
Freeze Sequence 3. Prechill The compressor is on for 30 seconds prior to water flow to prechill the evaporator. 4. Freeze The water pump restarts after the 30-second prechill. An even flow of water is directed across the evaporator and into each cube cell, where it freezes. The water fill valve will cycle on, then off one more time to refill the water trough.
Harvest Sequence 5. Water Purge The water pump continues to run, and the water dump valve energizes for 45 seconds to purge the water in the sump trough. The water fill valve energizes (turns on) and de-energizes (turns off) strictly by time. The water fill valve energizes for the last 15 seconds of the 45-second water purge.
Automatic Shut-Off 7. Automatic Shut-Off When the storage bin is full at the end of a harvest sequence, the sheet of cubes fails to clear the water curtain and will hold it open. After the water curtain is held open for 7 seconds, the ice machine shuts off. The ice machine remains off for 3 minutes before it can automatically restart.
REMOTE Initial Start-Up or Start-Up After Automatic Shut-Off 1. Water Purge Before the compressor starts, the water pump and water dump solenoid are energized for 45 seconds, to completely purge the ice machine of old water. This feature ensures that the ice making cycle starts with fresh water.
Freeze Sequence 3. Prechill The compressor is on for 30 seconds prior to water flow, to prechill the evaporator. 4. Freeze The water pump restarts after the 30 second prechill. An even flow of water is directed across the evaporator and into each cube cell, where it freezes. The water fill valve will cycle on and then off one more time to refill the water trough.
Harvest Sequence 5. Water Purge The water pump continues to run, and the water dump valve energizes for 45 seconds to purge the water in the sump trough. The water fill valve energizes (turns on) and de-energizes (turns off) strictly by time. The water fill valve energizes for the last 15 seconds of the 45-second water purge.
Electrical System WIRING DIAGRAMS The following pages contain electrical wiring diagrams. Be sure you are referring to the correct diagram for the ice machine which you are servicing. Warning Always disconnect power before working on electrical circuitry. Wiring Diagram Legend The following symbols are used on all of the wiring diagrams: Internal Compressor Overload...
Q200/Q280/Q320 - Self Contained - 1 Phase With Terminal Board CAUTION: DISCONNECT POWER BEFORE WORKING ON ELECTRICAL CIRCUITRY. WATER DIAGRAM SHOWN DURING FREEZE CYCLE VALVE L2 (N) SEE SERIAL PLATE FOR VOLTAGE (21) (22) (20) (61) HARVEST (60) SOLENOID (55) TB32 TB35 (77)
Q280/Q370 - Self Contained - 1 Phase Without Terminal Board SEE SERIAL PLATE FOR VOLTAGE CAUTION: DISCONNECT POWER BEFORE WORKING L2 (N) (21) (22) ON ELECTRICAL CIRCUITRY. (20) DIAGRAM SHOWN DURING FREEZE CYCLE WATER (61) VALVE (89) (55) (77) (60) HARVEST (80) SOLENOID...
Q320 - Self Contained - 1 Phase Without Terminal Board CAUTION: DISCONNECT POWER BEFORE WORKING ON ELECTRICAL CIRCUITRY. WATER DIAGRAM SHOWN DURING FREEZE CYCLE VALVE L2 (N) SEE SERIAL PLATE FOR VOLTAGE (22) (20) (61) HARVEST SOLENOID (55) (89) (77) (80) (60) HIGH PRES...
Q420/Q450/Q600/Q800/Q1000 - Self Contained- 1 Phase With Terminal Board CAUTION: DISCONNECT POWER BEFORE WORKING SEE SERIAL PLATE FOR VOLTAGE ON ELECTRICAL CIRCUITRY. DIAGRAM SHOWN DURING FREEZE CYCLE L2 (N) (20) (22) (21) (55) TB32 (61) WATER VALVE (60) HIGH PRES...
Q420/Q450/Q600/Q800/Q1000 - Self Contained- 1 Phase Without Terminal Board CAUTION: DISCONNECT POWER BEFORE WORKING L2 (N) ON ELECTRICAL CIRCUITRY. WATER DIAGRAM SHOWN DURING FREEZE CYCLE VALVE SEE SERIAL PLATE FOR VOLTAGE (22) (20) (21) (89) (55) (61) HARVEST HIGH PRES...
Q800/Q1000 - Self Contained - 3 Phase With Terminal Board SEE SERIAL PLATE FOR VOLTAGE CAUTION: DISCONNECT POWER BEFORE WORKING ON ELECTRICAL CIRCUITRY. L3 L2 L1 DIAGRAM SHOWN DURING FREEZE CYCLE (20) (21) (22) TB32 WATER TB35 (61) VALVE (60) HIGH PRES CUTOUT (77)
Q800/Q1000 - Self Contained - 3 Phase Without Terminal Board CAUTION: DISCONNECT POWER BEFORE WORKING SEE SERIAL PLATE FOR VOLTAGE ON ELECTRICAL CIRCUITRY. DIAGRAM SHOWN DURING FREEZE CYCLE WATER VALVE (22) (20) (21) (55) (89) (61) HARVEST SOLENOID HIGH PRES (88) CUTOUT (77)
Q1300/Q1800 - Self Contained - 1 Phase With Terminal Board SEE SERIAL PLATE FOR VOLTAGE CAUTION: DISCONNECT POWER BEFORE WORKING L2(N) ON ELECTRICAL CIRCUITRY. WATER DIAGRAM SHOWN DURING FREEZE CYCLE (21) VALVE (22) (20) (55) TB32 RH HARVEST TB35 SOLENOID (61) (88) (87)
Q1300/Q1600/Q1800 - Self Contained - 1 Phase Without Terminal Board CAUTION: DISCONNECT POWER BEFORE WORKING SEE SERIAL PLATE FOR VOLTAGE ON ELECTRICAL CIRCUITRY. DIAGRAM SHOWN DURING FREEZE CYCLE L2 (N) (20) (21) (22) WATER VALVE (55) (89) (61) HIGH PRES CUTOUT (77) (80)
Q1300/Q1800 - Self Contained - 3 Phase With Terminal Board SEE SERIAL PLATE FOR VOLTAGE CAUTION: DISCONNECT POWER BEFORE WORKING L3 L2 L1 ON ELECTRICAL CIRCUITRY. WATER DIAGRAM SHOWN DURING FREEZE CYCLE VALVE (21) (22) (20) RH HARVEST TB32 TB35 SOLENOID (61) (88)
Q1300/Q1600/Q1800 - Self Contained - 3 Phase Without Terminal Board CAUTION: DISCONNECT POWER BEFORE WORKING SEE SERIAL PLATE FOR VOLTAGE WATER ON ELECTRICAL CIRCUITRY. L3 L2 L1 VALVE DIAGRAM SHOWN DURING FREEZE CYCLE (22) (20) (21) (89) (55) RH HARVEST SOLENOID (61) (87)
Q450/Q600/Q800/Q1000 - Remote - 1 Phase With Terminal Board CAUTION: DISCONNECT POWER BEFORE WORKING SEE SERIAL PLATE FOR VOLTAGE ON ELECTRICAL CIRCUITRY. DIAGRAM SHOWN DURING FREEZE CYCLE L2 (N) (21) (22) WATER (20) VALVE TB32 (55) SOLENOID (61) TB35 (60)
Q450/Q600/Q800/Q1000 - Remote - 1 Phase Without Terminal Board CAUTION: DISCONNECT POWER BEFORE WORKING SEE SERIAL PLATE FOR VOLTAGE ON ELECTRICAL CIRCUITRY. DIAGRAM SHOWN DURING FREEZE CYCLE L2 (N) (20) (21) (22) WATER VALVE (89) (55) SOLENOID (61) (78) (79)
Q800/Q1000 -Remote - 3 Phase With Terminal Board SEE SERIAL PLATE FOR VOLTAGE CAUTION: DISCONNECT POWER BEFORE WORKING L3 L2 L1 ON ELECTRICAL CIRCUITRY. (21) (22) DIAGRAM SHOWN DURING FREEZE CYCLE WATER (20) VALVE SOLENOID TB32 (61) TB35 (60) (78) (79) HIGH PRES CUTOUT...
Q800/Q1000 - Remote - 3 Phase Without Terminal Board WATER CAUTION: DISCONNECT POWER BEFORE WORKING VALVE ON ELECTRICAL CIRCUITRY. L3 L2 L1 (21) (22) DIAGRAM SHOWN DURING FREEZE CYCLE SEE SERIAL PLATE FOR VOLTAGE (20) SOLENOID (88) (61) (89) (79) (78) HIGH PRES (55)
Q1300/Q1800 - Remote - 1 Phase With Terminal Board SEE SERIAL PLATE FOR VOLTAGE CAUTION: DISCONNECT POWER BEFORE WORKING ON ELECTRICAL CIRCUITRY. WATER L2 (N) DIAGRAM SHOWN DURING FREEZE CYCLE VALVE (21) (22) SOLENOID (20) (78) (79) (55) RH HARVEST TB32 TB35 SOLENOID...
Q1300/Q1600/Q1800 - Remote - 1 Phase Without Terminal Board WATER CAUTION: DISCONNECT POWER BEFORE WORKING VALVE L2 (N) ON ELECTRICAL CIRCUITRY. (22) (21) DIAGRAM SHOWN DURING FREEZE CYCLE SEE SERIAL PLATE FOR VOLTAGE SOLENOID (20) (78) (79) RH HARVEST (89) (55) SOLENOID (61)
Q1300/Q1800 - Remote - 3 Phase With Terminal Board WATER CAUTION: DISCONNECT POWER BEFORE WORKING VALVE ON ELECTRICAL CIRCUITRY. (22) (21) DIAGRAM SHOWN DURING FREEZE CYCLE SEE SERIAL PLATE FOR VOLTAGE (20) N - 50HZ (82) ONLY SOLENOID L3 L2 L1 GROUND (78) (79)
Q1300/Q1600/Q1800 - Remote - 3 Phase Without Terminal Board WATER VALVE CAUTION: DISCONNECT POWER BEFORE WORKING (21) (22) ON ELECTRICAL CIRCUITRY. N - 50 HZ DIAGRAM SHOWN DURING FREEZE CYCLE (20) ONLY SOLENOID SEE SERIAL PLATE FOR VOLTAGE L3 L2 L1 (79) (78) LH HARVEST...
COMPONENT SPECIFICATIONS AND DIAGNOSTICS General Q-Model control boards use a dual voltage transformer. This means only one control board is needed for both 115V and 208-230V use. Safety Limits In addition to standard safety controls, such as the high pressure cut-out, the control board has built-in safety limits.
Main Fuse FUNCTION The control board fuse stops ice machine operation if electrical components fail, causing high amp draw. SPECIFICATIONS The main fuse is 250 Volt, 7 amp. Warning High (line) voltage is applied to the control board (terminals #55 and #56) at all times. Removing the control board fuse or moving the toggle switch to OFF will not remove the power supplied to the control board.
Bin Switch FUNCTION Movement of the water curtain controls bin switch operation. The bin switch has two main functions: 1. Terminating the Harvest cycle and returning the ice machine to the Freeze cycle. This occurs when the bin switch is opened and closed again within 7 seconds during the Harvest cycle.
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CHECK PROCEDURE 1. Set the toggle switch to OFF. 2. Watch the bin switch light on the control board. 3. Move the water curtain toward the evaporator. The bin switch must close. The bin switch light “on” indicates the bin switch has closed properly. 4.
Water Curtain Removal Notes The water curtain must be on (bin switch closed) to start ice making. While a Freeze cycle is in progress, the water curtain can be removed and installed at any time without interfering with the electrical control sequence.
ICE/OFF/CLEAN Toggle Switch FUNCTION The switch is used to place the ice machine in ICE, OFF or CLEAN mode of operation. SPECIFICATIONS Double-pole, double-throw switch. The switch is connected into a varying low D.C. voltage circuit. CHECK PROCEDURE NOTE: Because of a wide variation in D.C. voltage, it is not recommended that a voltmeter be used to check toggle switch operation.
Ice Thickness Probe (Harvest Initiation) HOW THE PROBE WORKS Manitowoc’s electronic sensing circuit does not rely on refrigerant pressure, evaporator temperature, water levels or timers to produce consistent ice formation. As ice forms on the evaporator, water (not ice) contacts the ice thickness probe. After the water completes this circuit across the probe continuously for 6-10 seconds, a Harvest cycle is initiated.
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MAXIMUM FREEZE TIME The control system includes a built-in safety which will automatically cycle the ice machine into harvest after 60 minutes in the freeze cycle. ICE THICKNESS CHECK The ice thickness probe is factory-set to maintain the ice bridge thickness at 1/8 in. (.32 cm). NOTE: Make sure the water curtain is in place when performing this check.
Ice Thickness Probe Diagnostics Before diagnosing ice thickness control circuitry clean the ice thickness probe using the following procedure. 1. Mix a solution of Manitowoc ice machine cleaner and water (2 ounces of cleaner to 16 ounces of water) in a container.
Diagnosing Ice Thickness Control Circuitry ICE MACHINE DOES NOT CYCLE INTO HARVEST WHEN WATER CONTACTS THE ICE THICKNESS CONTROL PROBE Step 1. Bypass the freeze time lock-in feature by moving the ICE/OFF/CLEAN switch to OFF and back to ICE. Wait until the water starts to flow over the evaporator.
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Step 3. Disconnect the ice thickness probe from the control board at terminal 1C. Clip the jumper wire leads to terminal 1C on the control board and any cabinet ground. Monitor the Harvest light. Harvest Light On • The harvest light comes on, and 6-10 seconds later, the ice machine cycles from Freeze to Harvest.
Water Level Control Circuitry The water level probe circuit can be monitored by watching the water level light. The water level light is on when water contacts the probe, and off when no water is in contact with the probe. The water level light functions any time power is applied to the ice machine, regardless of toggle switch position.
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FREEZE CYCLE CIRCUITRY Manitowoc’s electronic sensing circuit does not rely on float switches or timers to maintain consistent water level control. During the Freeze cycle, the water inlet valve energizes (turns on) and de-energizes (turns off) in conjunction with the water level probe located in the water trough.
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DIAGNOSING WATER LEVEL CONTROL CIRCUITRY Problem: Water Trough Overfilling During the Freeze Cycle Step 1. Start a new Freeze sequence by moving the ICE/OFF/CLEAN toggle switch to OFF and then back to ICE. Important This restart must be done prior to performing diagnostic procedures.
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Step 2. Jumper Wire Connected from Probe to Ground Is Water The Water Flowing Water Inlet Valve into the Cause Level Solenoid Water Light Is: Coil Is: Trough? This is normal operation. De-energized Do not change any parts. The water inlet valve is De-energized causing the...
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Step 3. Allow ice machine to run. Disconnect the water level probe from control board terminal 1F, and connect a jumper wire from terminal 1F to any cabinet ground. Remember, if you are past 6 minutes from starting, the ice machine will go into a Freeze cycle water inlet valve safety shut-off mode, and you will be unable to complete this test.
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Problem: Water Will Not Run into the Sump Trough During the Freeze Cycle Step 1. Verify water is supplied to the ice machine, and then start a new Freeze sequence by moving the ICE/OFF/CLEAN toggle switch to OFF, then back to ICE.
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Step 3. Leave the ice machine run, and then disconnect the water level probe from control board terminal 1F. Important For the test to work properly you must wait until the Freeze cycle starts, prior to disconnecting the water level probe. If you restart the test, you must reconnect the water level probe, restart the ice machine (step 1), and then disconnect the water level probe after the compressor starts.
Diagnosing an Ice Machine Head Section that Will Not Run Warning High (line) voltage is applied to the control board (terminals #55 and #56) at all times. Removing control board fuse or moving the toggle switch to OFF will not remove the power supplied to the control board.
Compressor Electrical Diagnostics The compressor does not start or will trip repeatedly on overload. Check Resistance (Ohm) Values NOTE: Compressor windings can have very low ohm values. Use a properly calibrated meter. Perform the resistance test after the compressor cools. The compressor dome should be cool enough to touch (below 120°F/49°C) to assure that the overload is closed and the resistance readings will be accurate.
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CHECK MOTOR WINDINGS TO GROUND Check continuity between all three terminals and the compressor shell or copper refrigeration line. Scrape metal surface to get good contact. If continuity is present, the compressor windings are grounded and the compressor should be replaced. To determine if the compressor is seized, check the amp draw while the compressor is trying to start.
Diagnosing Capacitors • If the compressor attempts to start, or hums and trips the overload protector, check the starting components before replacing the compressor. • Visual evidence of capacitor failure can include a bulged terminal end or a ruptured membrane. Do not assume a capacitor is good if no visual evidence is present.
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• The voltage at the compressor during start-up is too low. Manitowoc ice machines are rated at ±10% of nameplate voltage at compressor start-up. (Ex: An ice machine rated at 208-230 should have a compressor start-up voltage between 187 and 253 volts.)
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Cera-Mite Model Temperature Part Number Part Number Resistance Q200 Q280 Q320 8505003 305C20 22-50 Ohms Q420 Q450 Q600 Q800 8504993 305C19 18-40 Ohms Q1000 Q1300 Q1600 8504913 305C9 8-22 Ohms Q1800 Manitowoc PTCR’s 8505003 & 8504993 Manitowoc PTCR’s 8504913 –68–...
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Refrigeration System REFRIGERATION SYSTEM DIAGNOSTICS Before Beginning Service Ice machines may experience operational problems only during certain times of the day or night. A machine may function properly while it is being serviced, but malfunctions later. Information provided by the user can help the technician start in the right direction, and may be a determining factor in the final diagnosis.
Ice Production Check The amount of ice a machine produces directly relates to the operating water and air temperatures. This means a condensing unit with a 70°F (21.2°C) outdoor ambient temperature and 50°F (10.0°C) water produces more ice than the same model condensing unit with a 90°F (32.2°C) outdoor ambient temperature and 70°F (21.2°C) water.
• Another ice machine is required. • More storage capacity is required. • Relocating the existing equipment to lower the load conditions is required. Contact the local Manitowoc Distributor for information on available options and accessories. Installation/Visual Inspection Checklist Possible Problem List •...
Water System Checklist A water-related problem often causes the same symptoms as a 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.
Analyzing the ice formation pattern alone cannot diagnose an ice machine malfunction. However, when this analysis is used along with Manitowoc’s Refrigeration System Operational Analysis Table, it can help diagnose an ice machine malfunction. Any number of problems can cause improper ice formation.
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2. Extremely Thin at Evaporator Outlet There is no ice, or a considerable lack of ice formation, on the top of the evaporator (tubing outlet). Examples: No ice at all on the top of the evaporator, but ice forms on the bottom half of the evaporator. Or, the ice at the top of the evaporator reaches 1/8 in.
Safety Limits GENERAL In addition to standard safety controls, such as high pressure cut-out, the control board has two built in safety limit controls which protect the ice machine from major component failures. There are two control boards with different safety limit sequences. Original production control boards have a black micro- processor.
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SAFETY LIMIT INDICATION Control Board with Black Microprocessor When a safety limit condition is exceeded for 3 consecutive cycles the ice machine stops and the harvest light on the control board continually flashes on and off. Use the following procedures to determine which safety limit has stopped the ice machine.
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When a safety limit condition is exceeded (6 consecutive cycles for Safety Limit #1 or 500 cycles for Safety Limit #2) the ice machine stops and the harvest light on the control board continually flashes on and off. Use the following procedures to determine which safety limit has stopped the machine.
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Eliminate all electrical components and external causes first. If it appears that the refrigeration system is causing the problem, use Manitowoc’s Refrigeration System Operational Analysis Table, along with detailed charts, checklists, and other references to determine the cause.
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SAFETY LIMIT NOTES • Because there are many possible external problems, do not limit your diagnosis to only the items listed in these charts. • A continuous run of 100 harvests automatically erases the safety limit code. • The control board will store and indicate only one safety limit –...
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Safety Limit #1 Refer to page 75 for control board identification and safety limit operation. Control Board with Black Microprocessor - Freeze Time exceeds 60 minutes for 3 consecutive freeze cycles Control Board with Orange Label on Microprocessor - Freeze time exceeds 60 minutes for 6 consecutive freeze cycles Possible Cause Checklist Improper Installation...
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Refrigeration System • Non-Manitowoc components • Improper refrigerant charge • Defective head pressure control (remotes) • Defective harvest valve • Defective compressor • TXV starving or flooding (check bulb mounting) • Non-condensable in refrigeration system • Plugged or restricted high side refrigerant lines or...
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• Ice thickness probe out of adjustment • Ice thickness probe dirty • Bin switch defective • Premature harvest Refrigeration System • Non-Manitowoc components • Water regulating valve dirty/defective • Improper refrigerant charge • Defective head pressure control valve (remotes) • Defective harvest valve •...
Analyzing Discharge Pressure 1. Determine the ice machine operating conditions: Air temp. entering condenser ______ Air temp. around ice machine ______ Water temp. entering sump trough ______ 2. Refer to Operating Pressure Chart for ice machine being checked. Use the operating conditions determined in step 1 to find the published normal discharge pressures.
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• Water regulating valve out of adjustment Improper Refrigerant Charge • Overcharged • Non-condensable in system • Wrong type of refrigerant Other • Non-Manitowoc components in system • High side refrigerant lines/component restricted (before mid-condenser) • Defective head pressure control valve –86–...
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• Wrong type of refrigerant Water regulating valve (water cooled condensers) • Out of adjustment • Defective Other • Non-Manitowoc components in system • High side refrigerant lines/component restricted (after mid-condenser) • Defective head pressure control valve • Defective fan cycle control NOTE: Do not limit your diagnosis to only the items listed in the checklists.
Analyzing Suction Pressure The suction pressure gradually drops throughout the Freeze cycle. The actual suction pressure (and drop rate) changes as the air 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.
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Procedure Example Using Step QY0454A Model Ice Machine Determine the ice Air temp. entering condenser: machine operating 90°F/32.2°C conditions. Air temp. around ice machine: 80°F/26.7°C Water temp. entering water fill valve: 70°F/21.1°C 2A. Refer to “Cycle Time” and “Operating Pressure” charts for ice machine 13.7-14.1 minutes model being checked.
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– refer to “Freeze Cycle Discharge Pressure High Checklist” Improper Refrigerant Charge • Overcharged • Wrong type of refrigerant Other • Non-Manitowoc components in system • HPR solenoid leaking • Harvest valve leaking • TXV flooding (check bulb mounting) • Defective compressor –90–...
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Improper Refrigerant Charge • Undercharged • Wrong type of refrigerant Other • Non-Manitowoc components in system • Improper water supply over evaporator – refer to “Water System Checklist” • Loss of heat transfer from tubing on back side of evaporator •...
The temperatures of the suction lines entering and leaving the evaporator alone cannot diagnose an ice machine. However, comparing these temperatures during the freeze cycle, along with using Manitowoc’s Refrigeration System Operational Analysis Table, can help diagnose an ice machine malfunction.
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3. Wait five minutes into the freeze cycle. 4. Record the temperatures below and determine the difference between them. 5. Use this with other information gathered on the Refrigeration System Operational Analysis Table to determine the ice machine malfunction. ____________ ____________ Inlet Temperature Outlet...
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The best way to diagnose a harvest valve is by using Manitowoc’s Ice Machine Refrigeration System Operational Analysis Table. Use the following procedure and table to help determine if a harvest valve is remaining partially open during the freeze cycle.
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Findings Comments The inlet of the harvest This is normal as the discharge valve is cool enough to line should always be too hot to touch and the touch and the harvest valve compressor discharge inlet, although too hot to touch line is hot.
Discharge Line Temperature Analysis GENERAL Knowing if the discharge line temperature is increasing, decreasing or remaining constant can be an important diagnostic tool. Maximum compressor discharge line temperature on a normally operating ice machine steadily increases throughout the freeze cycle. Comparing the temperatures over several cycles will result in a consistent maximum discharge line temperature.
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DISCHARGE LINE TEMPERATURE ABOVE 160°F (71.1°C) AT END OF FREEZE CYCLE: Ice machines that are operating normally will have consistent maximum discharge line temperatures above 160°F (71.1°C). DISCHARGE LINE TEMPERATURE BELOW 160°F (71.1°C) AT END OF FREEZE CYCLE: Ice machines that have a flooding expansion valve will have a maximum discharge line temperature that decreases each cycle.
How to Use the Refrigeration System Operational Analysis Tables GENERAL These tables must be used with charts, checklists and other references to eliminate refrigeration components not listed on the tables and external items and problems which can cause good refrigeration components to appear defective.
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NOTE: If two columns have matching high numbers, a procedure was not performed properly and/or supporting material was not analyzed correctly. FINAL ANALYSIS The column with the highest number of check marks identifies the refrigeration problem. COLUMN 1 - HARVEST VALVE LEAKING Replace the valve as required.
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COLUMN 3 - TXV FLOODING A loose or improperly mounted expansion valve bulb causes the expansion valve to flood. Check bulb mounting, insulation, etc., before changing the valve. On dual expansion valve machines, the service technician should be able to tell which TXV is flooding by analyzing ice formation patterns.
PRESSURE CONTROL SPECIFICATIONS AND DIAGNOSTICS Harvest Pressure Regulating (HPR) System Remotes Only GENERAL The harvest pressure regulating (H.P.R.) system includes: • Harvest pressure regulating solenoid valve (H.P.R. solenoid). This is an electrically operated valve which opens when energized, and closes when de- energized.
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• Harvest pressure regulating valve (H.P.R. valve). This is a pressure regulating valve which modulates open and closed, based on the refrigerant pressure at the outlet of the valve. The valve closes completely and stops refrigerant flow when the pressure at the outlet rises above the valve setting. INLET OUTLET SV3053...
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HPR DIAGNOSTICS Steps 1 through 4 can be quickly verified without attaching a manifold gauge set or thermometer. All questions must have a yes answer to continue the diagnostic procedure. 1. Liquid line warm? (Body temperature is normal) If liquid line is warmer or cooler than body temperature, refer to headmaster diagnostics.
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5. Freeze cycle Head Pressure 220 psig (1517 kPa) or higher? If the head pressure is lower than 220 psig (1517 kPa) refer to headmaster diagnostics. 6. Freeze cycle Suction Pressure normal? Refer to analyzing suction pressure if suction pressure is high or low. 7.
Headmaster Control Valve Manitowoc remote systems require headmaster control valves with special settings. Replace defective headmaster control valves only with “original” Manitowoc replacement parts. OPERATION The R404A headmaster control valve is non adjustable. At ambient temperatures of approximately 70°F (21.1°C) or above, refrigerant flows through the valve from the condenser to the receiver inlet.
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Lower ambient conditions can be simulated by rinsing the condenser with cool water during the freeze cycle. Probable Corrective Symptom Cause Measure Valve not Non- Install a Manitowoc maintaining approved Headmaster control pressures valve valve with proper setting Discharge pressure Ice machine See “Low on...
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LOW ON CHARGE VERIFICATION The remote ice machine requires more refrigerant charge at lower ambient temperatures than at higher temperatures. A low on charge ice machine may function properly during the day, and then malfunction at night. Check this possibility. If you cannot verify that the ice machine is low on charge: 1.
High Pressure Cutout (HPCO) Control FUNCTION Stops the ice machine if subjected to excessive high- side pressure. The HPCO control is normally closed, and opens on a rise in discharge pressure. Specifications Cut-Out Cut-In 450 psig ±10 Manual or Automatic (3103 kPa ±69) Reset (Must be below 300 psig (2068 kPa) to reset.)
REFRIGERATION TUBING SCHEMATICS Self-Contained Air- or Water -Cooled Models Q200/Q280/Q320/Q370/Q420/Q450/Q600/Q800/Q1000 E V A P O R A T O R H E A T E X C H A N G E R E X P A N S I O N V A L V E...
CYCLE TIMES/24-HOUR ICE PRODUCTION/ REFRIGERANT PRESSURE CHARTS These charts are used as guidelines to verify correct ice machine operation. Accurate collection of data is essential to obtain the correct diagnosis. • Refer to “OPERATIONAL ANALYSIS TABLE” for the list of data that must be collected for refrigeration diagnostics.
Q200 Series - Self-Contained Air-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time Air Temp. Entering Harvest Water Temperature °F/°C Condenser Time °F/°C 50/10.0 70/21.1 90/32.2 70/21.1 11.5-13.5 13.8-16.1 15.2-17.8 80/26.7 13.8-16.1 15.6-18.2 17.0-19.8 1.0-2.5 90/32.2 16.1-18.7 18.6-21.6 20.5-23.8 100/37.8...
Q200 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Around Ice Harvest Water Temperature °F/°C Machine Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 11.5-13.5 12.8-15.0 14.5-16.9...
Q280 Series - Self-Contained Air-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 10.6-12.5 11.8-13.8 12.6-14.7 80/26.7...
Q280 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Around Ice Harvest Water Temperature °F/°C Machine Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 10.6-12.5 12.0-14.1 12.3-14.4...
Q320 Series - Self-Contained Air-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 12.2-13.9 13.1-14.9 14.2-16.2 80/26.7...
Q320 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Around Ice Harvest Water Temperature °F/°C Machine Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 12.6-14.4 13.6-15.5 15.4-17.6...
Q370 Series - Self-Contained Air-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 10.3-11.7 11.7-13.4 12.6-14.4 80/26.7...
Q370 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Around Ice Harvest Water Temperature °F/°C Machine Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 10.3-11.7 11.0-12.5 12.2-13.9...
Q420/450 Series - Self-Contained Air-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 9.7-11.4 10.9-12.8 12.0-14.0 80/26.7...
Q420/450 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Around Ice Harvest Water Temperature °F/°C Machine Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 9.9-11.7 11.4-13.4 12.6-14.8...
Q450 Series - Remote Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C -20/-28.9 to 70/ 10.6-12.5...
Q600 Series - Self-Contained Air-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 7.1-8.4 7.8-9.2 8.6-10.1 80/26.7...
Q600 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Around Ice Water Temperature °F/°C Harvest Time Machine 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 7.4-8.7 8.2-9.7 9.5-11.2...
Q600 Series - Remote Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Freeze Time Air Temp. Entering Harvest Condenser Water Temperature °F/°C Time °F/°C 50/10.0 70/21.1 90/32.2 -20/-28.9 to 70/21.1 7.9-9.4 8.9-10.5 9.5-11.2...
Q800 Series - Self-Contained Air-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 8.9-10.2 9.7-11.1 10.3-11.9 80/26.7...
Q800 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Around Ice Harvest Water Temperature °F/°C Machine Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 8.7-10.1 9.5-11.0 10.9-12.5...
Q800 Series - Remote Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C -20/-28.9 to 70/ 9.5-11.0 10.6-12.2 11.6-13.4...
Q1000 Series - Self-Contained Air-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 9.9-10.6 10.6-11.4 11.3-12.2 80/26.7...
Q1000 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Around Ice Harvest Water Temperature °F/°C Machine Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 10.0-10.7 10.6-11.4 12.1-13.0...
Q1000 Series - Remote Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C -20/-28.9 to 70/ 10.5-11.3 11.3-12.2 12.1-13.0...
Q1300 Series - Self-Contained Air-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 9.4-10.5 9.9-11.1 10.9-12.2 80/26.7...
Q1300 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Around Ice Harvest Water Temperature °F/°C Machine Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 9.0-10.1 9.8-10.9 11.4-12.6...
Q1300 Series - Remote Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C -20/-28.9 to 70/ 9.9-11.1 10.9-12.2 11.7-13.0...
Q1600 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Freeze Time Air Temp. Entering Harvest Condenser Water Temperature °F/°C Time °F/°C 50/10.0 70/21.1 90/32.2 70/21.1 7.2-8.1 8.0-9.0 8.9-9.9 1-2.5...
Q1600 Series - Remote Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C -20 to 70 7.5-8.4 8.2-9.2 9.0-10.1...
Q1800 Series - Self-Contained Air-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 8.5-9.3 9.4-10.3 9.9-10.9 80/26.7...
Q1800 Series - Self-Contained Water-Cooled Characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Around Ice Harvest Water Temperature °F/°C Machine Time 50/10.0 70/21.1 90/32.2 °F/°C 70/21.1 8.7-9.6 9.6-10.5 10.8-11.9...
Q1800 Series - Remote These characteristics may vary depending on operating conditions. CYCLE TIMES Freeze Time + Harvest Time = Total Cycle Time Air Temp. Freeze Time Entering Harvest Water Temperature °F/°C Condenser Time 50/10.0 70/21.1 90/32.2 °F/°C -20/-28.9 to 70/ 9.1-10.0 9.8-10.8 10.7-11.7...
Important Replace the liquid line drier before evacuating and recharging. Use only a Manitowoc (OEM) liquid line filter-drier to prevent voiding the warranty. CONNECTIONS Manifold gauge sets must utilize low loss fittings to comply with U.S.
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SELF-CONTAINED RECOVERY/EVACUATION 1. Place the toggle switch in the OFF position. 2. Install manifold gauges, charging cylinder/scale, and recovery unit or two-stage vacuum pump. MANIFOLD SET OPEN OPEN BACKSEATED BACKSEATED LOW SIDE HIGH SIDE SERVICE SERVICE VALVE VALVE VACUUM PUMP/ RECOVERY UNIT OPEN CLOSED...
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SELF-CONTAINED CHARGING PROCEDURES Important The charge is critical on all Manitowoc ice machines. Use a scale or a charging cylinder to ensure the proper charge is installed. 1. Be sure the toggle switch is in the OFF position. MANIFOLD SET...
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2. Close the vacuum pump valve, the low side service valve, and the low side manifold gauge valve. 3. Open the high side manifold gauge valve, and backseat the high side service valve. 4. Open the charging cylinder and add the proper refrigerant charge (shown on nameplate) through the discharge service valve.
Do not purge refrigerant to the atmosphere. Capture refrigerant using recovery equipment. Follow the manufacturer’s recommendations. Important Manitowoc Ice, Inc. assumes no responsibility for the use of contaminated refrigerant. Damage resulting from the use of contaminated refrigerant is the sole responsibility of the servicing company.
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NOTE: Manitowoc recommends using an access valve core removal and installation tool on the discharge line quick-connect fitting. This permits access valve core removal. This allows for faster evacuation and charging, without removing the manifold gauge hose.
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EVAPORATOR HEAT EXCHANGER EXPANSION VALVE HARVEST SOLENOID VALVES LOW SIDE SERVICE VALVE (BACKSEATED) COMPRESSOR STRAINER HARVEST PRESSURE HARVEST CHECK SOLENOID PRESSURE VALVE VALVE REGULATING VALVE HIGH SIDE LIQUID SERVICE VALVE LINE (BACKSEATED) SOLENOID DISCHARGE LINE QUICK CONNECT DRIER SCHRAEDER FITTING REMOTE CONDENSER RECEIVER SERVICE VALVE...
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REMOTE CHARGING PROCEDURES 1. Be sure the toggle switch is in the OFF position. 2. Close the vacuum pump valve, the low and high side service valves (frontseat), and the low side manifold gauge valve. 3. Open the charging cylinder and add the proper refrigerant charge (shown on nameplate) into the system high side (receiver outlet valve and discharge lines quick-connect fitting).
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EVAPORATOR HEAT EXCHANGER EXPANSION VALVE HARVEST SOLENOID VALVES LOW SIDE SERVICE VALVE (BACKSEATED) COMPRESSOR STRAINER HARVEST PRESSURE HARVEST CHECK SOLENOID PRESSURE VALVE VALVE REGULATING VALVE HIGH SIDE LIQUID SERVICE VALVE LINE (BACKSEATED) SOLENOID DISCHARGE LINE QUICK CONNECT DRIER SCHRAEDER FITTING REMOTE CONDENSER RECEIVER SERVICE VALVE...
This section describes the basic requirements for restoring contaminated systems to reliable service. Important Manitowoc Ice, Inc. assumes no responsibility for the use of contaminated refrigerant. Damage resulting from the use of contaminated refrigerant is the sole responsibility of the servicing company.
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Contamination Cleanup Chart Required Cleanup Symptoms/Findings Procedure No symptoms or suspicion Normal of contamination evacuation/recharging procedure Moisture/Air Contamination symptoms • Refrigeration system open to atmosphere for Mild contamination longer than 15 minutes cleanup procedure • Refrigeration test kit and/or acid oil test shows contamination •...
Cleanup Procedure MILD SYSTEM CONTAMINATION 1. Replace any failed components. 2. If the compressor is good, change the oil. 3. Replace the liquid line drier. NOTE: If the contamination is from moisture, use heat lamps during evacuation. Position them at the compressor, condenser and evaporator prior to evacuation.
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SEVERE SYSTEM CONTAMINATION 1. Remove the refrigerant charge. 2. Remove the compressor. 3. Disassemble the harvest solenoid valve. If burnout deposits are found inside the valve, install a rebuild kit, and replace the manifold strainer, TXV and harvest pressure regulating valve. 4.
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Important Dry nitrogen is recommended for this procedure. This will prevent CFC release. 10. 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.
Replacing Pressure Controls Without Removing Refrigerant Charge This procedure reduces repair time and cost. Use it when any of the following components require replacement, and the refrigeration system is operational and leak-free. • Fan cycle control (air cooled only) • Water regulating valve (water cooled only) •...
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FIG. A - “PINCHING OFF” TUBING FIG. B - RE-ROUNDING TUBING SV1406 USING PINCH-OFF TOOL –163–...
Filter-Driers The filter-driers used on Manitowoc ice machines are manufactured to Manitowoc specifications. The difference between a Manitowoc drier and an off- the-shelf drier is in filtration. A Manitowoc drier 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 harvest cycle.
Water-Cooled 15 oz Air-Cooled 20 oz. Q320 Water-Cooled 16 oz. Air-Cooled 20 oz. Q370 Water-Cooled 17 oz. Air-Cooled 24 oz. Q420/Q450 Water-Cooled 22 oz. Remote 6 lb. Air-Cooled 28 oz. Q600 Water-Cooled 22 oz. Remote 8 lb. Air-Cooled 36 oz.
ADDITIONAL REFRIGERANT CHARGES For Line Sets Between 50’ - 100’. Refrigerant Maximum to be Nameplate System Added for Machine Charge Charge 50'-100' Never Exceed Line Sets 6 lb. 6 lb. Q490 None (96 oz.) (96 oz.) 8 lb. 8 lb. Q690 None (128 oz.)
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