for SUB-ZERO models including: Pro-Series, Pro-Series 15 Inch Ice Maker, 15 Inch Ice Maker, Ice Maker
• The ice ejector begins to turn and the shut-off arm begins to rise. Figure 6-3. Start of First Revolution. APPROXIMATE POSITION. OF ICE EJECTOR AND. ICE LEVEL ...
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DocumentDocumentIcemaker Information Pro-Series (648PRO) ICEMAKER SYSTEM INFORMATION The model 648PRO utilizes a MidSouth ® icemaker, or a Japan-Servo ® icemaker, for which the operating characteristics of each are similar. Icemaker operation is not complex, but icemaker components and operation cycles should be understood by a Service Technician in order to make proper diagnosis. TO AVOID ELECTRIC SHOCK, ALWAYS DISCONNECT ELECTRICAL POWER TO UNIT WHEN SERVICING ICEMAKER. NOTE: The ICE MAKER key at the control panel activates the icemaker system. If the ice making icon is not displayed on the LCD, the icemaker system is OFF. NOTE: To allow ice to freeze fully and reduce effects of low water pressure, the electronic control disables the icemaker system for 45 minutes after each ice harvest. ICEMAKER COMPONENTS Following are descriptions that explain the function of each icemaker component. The components are diagramed in Figure 6-1 on the next page. Support - The support is the housing around the electrical components and wire connections. The support is attached to the ice mold. Mounting Plate - The drive motor, holding switch, water valve solenoid switch, timing gear, timing cam and water fill adjusting screw are attached to the metal mounting plate. The mounting plate is then attached to the support. Drive Motor - AC power supplied to the drive motor causes the motor to operate. The motor has a single output shaft with a small gear. The motor gear drives/spins the timing gear. Timing Gear - The timing gear is driven/spun by the drive motor gear and is attached to the timing cam. Timing Cam - The timing cam is attached to the timing gear, and the ice ejector is inserted into the center of the timing cam. As the timing cam rotates, high and low spots on the cam operate the water valve solenoid switch and the holding switch. The timing cam also moves the lever arm side to side and rotates the ice ejector. Ice Mold - The ice mold is where the eight crescent shaped ice cubes are formed. Mold Heater - The mold heater uses 175 watts to thaw the ice free from the mold. Ice Ejector - The drive end of the ice ejector is "D" shaped to fit into the "D" shaped hole in the timing cam. It has eight blades which rotate and sweep the ice from the mold cavities during the ejection phase of the cycle. Ice Stripper - The stripper is attached to the dumping side of the mold, serving as a decorative side cover and it also prevents ice from falling back into the mold. Bearing / Inlet - The bearing / inlet is attached to the ice mold, opposite the support. Water enters the bearing / inlet and is directed to the ice mold. The bearing/inlet also supports the ice ejector at the end opposite the timing cam. Thermostat - The thermostat is a single-pole, singlethrow, bi-metal switch. At 15°F (-9°C) ± 3° it closes, starting the ice ejection phase. Thermal-Mastic - A substance similar in appearance to grease that is applied between the thermostat and the ice mold. Its purpose is to increase thermal conductivity between the mold and the thermostat. Lever Arm and Shut-off Arm - The lever arm is moved side to side by two revolutions of the timing cam. As it moves, it raises and lowers the shut-off arm and operates the shut-off switch to control quantity of ice production. If shut-off arm comes to rest on top of the ice in the storage bin during either revolution, the shut-off switch will remain open, stopping ice production at the end of that revolution. Water Valve Solenoid Switch - A single-pole, doublethrow type switch that allows electricity to the water valve solenoid, opening the valve, during the fill cycle. Holding Switch - A single-pole, double-throw type switch that assures completion of a revolution once the icemaker has been energized. Shut-off Switch - A single-pole, double-throw type switch that stops ice production when the ice bin is full. TCO (Thermal Cut Out) - The TCO is thermal protection device in the wire harness that would open in the event of mechanical failure, thus protecting against over heating. (The TCO is not shown in diagram.) #3758440 - Revision B - November, 2006 6-2 Pro-Series (648PRO) Icemaker Information Ice Ejector (Location of Thermal-Mastic) Shut-off Switch Support Thermostat Drive Motor Holding Switch Bearing / Inlet Ice Stripper Support Plate Timing Gear Ice Mold and Mold Heater Ice Level Arm Lever Arm Cover Timing Cam Water Valve Solenoid Switch Figure 6-1. Diagram of Icemaker Components ICEMAKER OPERATION The following series of electrical schematics illustrate a typical icemaker cycle of operation. Below each schematic is a diagram indicating the approximate location of the ice ejector and ice level arm during the phase the schematic indicates. Freeze Phase of Ice Making Cycle (See Figure 6-2) · The ice mold is filled with water. · The thermostat is open. · No icemaker componentS are energized. 115 VOLTS 60 CYCLES TCO SHUT-OFF SWITCH NO C NC THERMOSTAT MOLD HEATER SOLENOID SWITCH NC NO WATER SOLENOID C NC C NO HOLDING SWITCH MOTOR APPROXIMATE POSITION OF ICE EJECTOR AND ICE LEVEL ARM DURING OPERATION WATER ICE MOLD ICE BUCKET Figure 6-2. The Freeze Phase 6-3 #3758440 - Revision B - November, 2006 Icemaker Information Pro-Series (648PRO) Start of the First Revolution (See Figure 6-3) · The water in the ice mold has turned to ice. · At 15°F (-9°C) ± 3° the thermostat closes. · Mold heater is energized through the thermostat. · The drive motor is started through the thermostat and "normally closed" terminal of the holding switch. · The ice ejector begins to turn and the shut-off arm begins to rise. 115 VOLTS 60 CYCLES TCO SHUT-OFF SWITCH NO C NC THERMOSTAT MOLD HEATER SOLENOID SWITCH NC NO WATER SOLENOID C NC C NO HOLDING SWITCH MOTOR APPROXIMATE POSITION OF ICE EJECTOR AND ICE LEVEL ARM DURING OPERATION ICE ICE MOLD ICE BUCKET Figure 6-3. Start of First Revolution First Revolution Continued (See Figure 6-4) · The holding switch is tripped by the timing cam to "normally open" thus holding power to the motor. · The mold heater remains energized through the thermostat. · The shut-off arm begins to rise. 115 VOLTS 60 CYCLES TCO SHUT-OFF SWITCH NO C NC THERMOSTAT MOLD HEATER SOLENOID SWITCH NC NO WATER SOLENOID C NC C NO HOLDING SWITCH MOTOR #3758440 - Revision B - November, 2006 APPROXIMATE POSITION OF ICE EJECTOR AND ICE LEVEL ARM DURING OPERATION ICE ICE MOLD ICE BUCKET Figure 6-4. First Revolution Continued 6-4 Pro-Series (648PRO) First Revolution Continued (See Figure 6-5) · The ice ejector reaches the ice in the mold. · The ice releases from the mold as the ejector blades begin to rotate the cubes out. · The drive motor remains energized through the hold- ing switch. · The mold heater remains energized through the ther- mostat. · As the shut-off arm rises, the shut off switch is tripped to "normally closed", and then the shut-off arm begins to lower. Icemaker Information 115 VOLTS 60 CYCLES TCO SHUT-OFF SWITCH NO C NC THERMOSTAT MOLD HEATER SOLENOID SWITCH NC NO WATER SOLENOID C NC C NO HOLDING SWITCH MOTOR APPROXIMATE POSITION OF ICE EJECTOR AND ICE LEVEL ARM DURING OPERATION ICE ICE MOLD ICE BUCKET Figure 6-5. First Revolution Continued First Revolution Continued (See Figure 6-6) · The ice has released from the mold. · The motor remains energized through the holding switch. · The shut-off arm is lowered and the shut off switch is tripped to "normally open". · The water valve solenoid switch is tripped by the tim- ing cam, but the solenoid is not energized, because the thermostat is still closed and is energizing the mold heater. (Electric current follows the path of least resistance.) 115 VOLTS 60 CYCLES TCO SHUT-OFF SWITCH NO C NC THERMOSTAT MOLD HEATER SOLENOID SWITCH NC NO WATER SOLENOID C NC C NO HOLDING SWITCH MOTOR ICE APPROXIMATE POSITION OF ICE EJECTOR AND ICE LEVEL ARM DURING OPERATION ICE MOLD ICE BUCKET Figure 6-6. First Revolution Continued 6-5 #3758440 - Revision B - November, 2006 Icemaker Information Pro-Series (648PRO) End of First Revolution (See Figure 6-7) · The water valve solenoid switch is tripped by the timing cam back to "normally open." · The timing cam trips the holding switch to "normally close," which ends the first revolution, but the thermostat is still closed, so the motor is again started. · The mold heater remains energized through the thermostat. 115 VOLTS 60 CYCLES TCO SHUT-OFF SWITCH NO C NC THERMOSTAT MOLD HEATER SOLENOID SWITCH NC NO WATER SOLENOID C NC C NO HOLDING SWITCH MOTOR APPROXIMATE POSITION OF ICE EJECTOR AND ICE LEVEL ARM DURING OPERATION ICE ICE MOLD ICE BUCKET Figure 6-7. End of First Revolution Start of Second Revolution:(See Figure 6-8) · The water valve solenoid switch is tripped by the timing cam back to "normally open." · The timing cam trips the holding switch to "normally close," which ends the first revolution, but the thermostat is still closed, so the motor is again started. · The mold heater remains energized through the thermostat. 115 VOLTS 60 CYCLES TCO SHUT-OFF SWITCH NO C NC THERMOSTAT MOLD HEATER SOLENOID SWITCH NC NO WATER SOLENOID C NC C NO HOLDING SWITCH MOTOR APPROXIMATE POSITION OF ICE EJECTOR AND ICE LEVEL ARM DURING OPERATION ICE ICE MOLD ICE BUCKET Figure 6-8. Start of Second Revolution #3758440 - Revision B - November, 2006 6-6 Pro-Series (648PRO) Second Revolution Continued (See Figure 6-9) · The mold heater has warmed the thermostat, so the thermostat opens, and the mold heater is de-energized. · If the shut-off arm comes to rest on top of the ice in the storage bin (as illustrated), the shut-off switch will remain in the "normally closed" position. · The motor remains energized through the holding switch. Icemaker Information 115 VOLTS 60 CYCLES TCO SHUT-OFF SWITCH NO C NC THERMOSTAT MOLD HEATER SOLENOID SWITCH NC NO WATER SOLENOID C NC C NO HOLDING SWITCH MOTOR Second Revolution Continued (See Figure 6-10) · The water valve solenoid switch is tripped by the timing cam. This time the solenoid is energized because the thermostat is open. The water solenoid is open for approximately seven seconds, filling the ice mold with water. · The mold heater is energized through the solenoid switch and holding switch. APPROXIMATE POSITION OF ICE EJECTOR AND ICE MOLD ICE ICE ICE LEVEL ARM DURING OPERATION ICE BUCKET Figure 6-9. Second Revolution Continued 115 VOLTS 60 CYCLES TCO SHUT-OFF SWITCH NO C NC THERMOSTAT MOLD HEATER SOLENOID SWITCH NC NO WATER SOLENOID C NC C NO HOLDING SWITCH MOTOR APPROXIMATE POSITION OF ICE EJECTOR AND ICE MOLD ICE ICE ICE LEVEL ARM DURING OPERATION ICE BUCKET Figure 6-10. Second Revolution Continued 6-7 #3758440 - Revision B - November, 2006 Icemaker Information Pro-Series (648PRO) End of Ice making Cycle (See Figure 6-11) · The water valve solenoid switch is tripped by the timing cam back to "normally open" ending the water fill. · The timing cam trips the holding switch to "normally close," which ends the second revolution. · The thermostat is still open, so it does not start the drive motor. · If the shut-off arm has come to rest on top of the ice in storage bin (as illustrated), the shut-off switch remains in the "normally closed" position. This interrupts power from reaching the thermostat, until sufficient ice has been removed from the storage bin allowing the shut-off arm to lower. NOTE: To allow ice to freeze fully and reduce effects of low water pressure, the electronic control system disables the icemaker system for 45 minutes after each ice harvest. 115 VOLTS 60 CYCLES TCO SHUT-OFF SWITCH NO C NC THERMOSTAT MOLD HEATER SOLENOID SWITCH NC NO WATER SOLENOID C NC C NO HOLDING SWITCH MOTOR WATER APPROXIMATE POSITION OF ICE EJECTOR AND ICE MOLD ICE ICE ICE LEVEL ARM DURING OPERATION ICE BUCKET Figure 6-11. End of Ice Making Cycle MANUALLY STOPPING ICE PRODUCTION Ice production can be manually stopped by pressing the ICE MAKER key on the control panel so that the ice making icon is not displayed on the left User Display. NOTES: · If the ice level arm sticks in the "up" position, ice pro- duction will stop (See Figure 6-12). · Removing the ice bucket will NOT stop ice produc- tion, as there is no ice maker rocker-switch used in this series. Arm UP, Icemaker will Stop Arm DOWN, Icemaker will Operate Figure 6-12. Stopping Icemaker #3758440 - Revision B - November, 2006 6-8 Pro-Series (648PRO) Icemaker Information MANUALLY STARTING THE ICEMAKER NOTE: To allow ice to freeze fully and reduce effects of low water pressure, the electronic control disables the icemaker system for 45 minutes after each ice harvest. To bypass this 45 minute dwell for service purposes, press the the ICE key at the control panel. Manual Start Procedure: 1. Pry the icemaker front cover from the support using a flat-blade screwdriver or coin. 2. With a flat-blade screwdriver, turn the drive gear counterclockwise until the holding switch is activated, completing the circuit to the drive motor (this will be about a 1/8 turn). (See Figure 6-13) The icemaker will then complete its cycle automatically. NOTE: If after 1/4 turn the icemaker is not running on its own, it may be in the 45 minute dwell period or there is an electrical or mechanical problem. Turn Drive Gear Counterclockwise Figure 6-13. Manually Start Icemaker ADJUSTING WATER FILL LEVEL Proper water fill level for a MidSouth icemaker is 100 110 cc's (3.5 - 3.75 oz). If the fill level is checked and needs to be adjusted, turn the water fill adjusting screw clockwise to reduce fill level, or counterclockwise to increase fill level. One full turn of the screw equals 15 cc's. (See Figure 6-14) NOTE: Always check fill level before making any adjustments of the water fill adjusting screw. Water Fill Adjusting Screw 1 Full Turn Equals 15 CC's Turn Clockwise to Reduce Fill Figure 6-14. Adjust Water Fill Level 6-9 #3758440 - Revision B - November, 2006 Icemaker Information Pro-Series (648PRO) ICEMAKER FAULT TESTING Possible Problems Bypass 45-minute dwell by pressing ICE ON/OFF key to OFF then ON. Then depress icemaker switch & manually start icemaker by turning driver gear counter-clockwise with screwdriver. 1 If icemaker starts & finishes cycle: (NOTE: If >15°F (-9°C), icemaker will only complete 1 revolution.) a. Visually inspect electrical connections at icemaker & valve. Repair if necessary. b. Check valve operation with test cord, if doesn't open, replace. c. Check thermostat. Open: 48° (9°C) ± 6°, Close: 15° (-9°C) ± 3°. Replace icemaker if defective. d. With icemaker in park position, check solenoid switch terminals "C" & "NO" for continuity. With ejector between 8:00 & 10:00 position, check solenoid switch terminals "C" & "NC" for continuity. If no continuity for either terminal check, replace icemaker. 2. If icemaker starts but does not finish cycle: a. With icemaker in park position check holding switch terminals "C" & "NC" for continuity. Then with icemaker ejector between 10:00 & 12:00, check holding switch terminals "C" & "NO" for continuity. If no continuity for either terminal check, replace icemaker. (Refer to enclosed wiring diagram) b. With icemaker in park position check shut-off switch terminals "C" & "NO" for continuity. With ejector between 12:00 & 2:00 check shut-off switch terminals "C" & "NC" for continuity. If no continuity for either terminal check, replace icemaker. c. Check mold heater for 75-85. If outside range, replace icemaker. 3 If icemaker motor does NOT start: a. Lower shutoff arm b. Check motor operation with test cord. If motor doesn't run, replace icemaker. c. Check power to & from icemaker switch. Reconnect or repair connection or replace icemaker as necessary. d. Check for 115V AC from control board. If power is present check & repair connection. If no power, replace control board. QUICK REFERENCE · Water Fill Time - 6.3±.2 seconds · Fill Tube Heater Ohm - 2850-3890 · Mold Heater Ohm - 75-85 · Water Valve Ohm - 160-165 · Thermostat - Open: 48° (9°C) ± 6°, Close: 15° (-9°C) ± 3°. · Water Pressure Needed - 20-100 psi constant No / Slow Ice Production 1 Ice maker system switched OFF. Switch ice system ON. 2 Shut off arm in up/OFF position. Move to ON position. 3 Freezer too warm. Check temp's & see troubleshooting guide in service manual. 4 Poor airflow over icemaker. Remove obstructions. 5 Ice cube jam. Remove ice & check water fill setting. a. Water fill setting too low (< 6.5 sec's). Adjust setting. b. Water fill setting too high (> 7 sec's). Adjust setting. 6 Water froze in inlet tube. Remove ice from tube. Check for 115VAC from control board; Fill tube heater = 28503890. 7 Water supply not constant 20-100 psi. Instruct customer. 8 Water line to unit pinched/kinked. Repair water line. 9 Saddle valve not installed correctly to supply line. Reposition. 10 Saddle valve not fully open. Open valve fully. 11 Icemaker wire/connections loose/broken. Repair wiring. 12 Water valve wire/connections loose/broken. Repair wiring. 13 Defective water valve. Check valve (160-165), Replace valve. 14 Thermostat wire/connections loose/broken. Repair wiring. 15 TCO overheat or short. Replace icemaker. 16 See Icemaker Fault Testing. No Water Fill 1 Water supply switched OFF. Switch supply water line ON. 2 Water line to unit pinched/kinked. Repair water line. 3 Saddle valve not installed correctly to supply line. Reposition. 4 Water froze in inlet tube. Remove ice from tube. Check for 115VAC from control board; Fill tube heater = 28503890. 5 Water valve wire/connections loose/broken. Repair wiring. 6 Defective water valve. Check valve (160-165), Replace valve. Overflows / Ice Block Forms in Bucket / Oversized Cubes 1 Icemaker not level. Level icemaker. 2 Unit not level. Level unit 3 Water supply not constant 20-100 psi. Instruct customer. 4 Water fill setting too high (> 7 sec's). Adjust setting. 5 Water fill setting too low (< 6.5 sec's). Adjust setting. 6 Defective water valve. Check valve (160-165), Replace valve. Ice Cubes Hollow or Small 1 Icemaker not level. Level icemaker. 2 Unit not level. Level unit 3 Water supply not constant 20-100 psi. Instruct customer. 4 Water fill setting too low (< 6.5 sec's). Adjust setting. 5 Too little thermalmastic on thermostat. Add thermalmastic. 6 Defective thermostat (Open: 48° (9°C) ± 6°, Close: 15° (-9°C) ± 3°. Replace icemaker if defective. #3758440 - Revision B - November, 2006 Too much Ice 1 Shut off arm/linkage bent/broken. Repair or replace arm/linkage. 2 If ejector blades rotate with arm in up/OFF position - Icemaker faulty. Replace icemaker. 6-10iTextSharp™ 5.5.5 ©2000-2014 iText Group NV (AGPL-version); modified using iTextSharp™ 5.5.5 ©2000-2014 iText Group NV (AGPL-version)