NSE650 INTRODUCTION To the owner or user: The service manual you are reading is intended to provide you, and the maintenance or service technician, with the information needed to install, start up, clean, maintain, and service this ice system. The NSE650 is a complete ice system that produces and stores nugget ice.
NSE650 FOR THE INSTALLER Installation Limitations: This ice system is designed to be installed indoors, in a controlled environment: Min. Max. Air Temperature 500F 1000F Water Temperature 400F 1000F Water Pressure 20 PSI 80 PSI Voltage 104 126 (Compared to the nameplate) Operating the machine outside of the limitations is misuse and can void the warranty.
NSE650 FOR THE INSTALLER: Environmental Limitations Location After uncrating the machine, and inspecting it for freight damage, the unit is ready for installation. It is important that the machine be installed in a location where it has enough space for service access. The unit will require removal of the top panel for some service, so in under counter applications, the unit will either have to be pulled out, or the countertop will have to be removable.
NSE650 FOR THE PLUMBER CONFORM TO ALL APPLICABLE CODES Water Inlet Air Cooled Models: The recommended water supply is clean, cold water. Use 3/8" O.D. copper tubing, connect to the 3/8" male flare at the back of the cabinet. Install a hand valve near the machine to control the water supply. Water Treatment: In most areas, a water filter of some type will be useful.
NSE650 FOR THE ELECTRICIAN CONFORM TO ALL APPLICABLE CODES The electrical power to the unit is supplied through the junction box at the rear of the machine. Check the nameplate (located on the back panel) for the voltage requirements, and for the minimum circuit ampacity. The machine requires a solid chassis to earth ground wire. The ice maker should be connected to its own electrical circuit so it would be individually fused.
NSE650 FOR THE INSTALLER Final Check List 1. Is the ice system installed indoors in a location where the air and water temperatures are controlled, and where they do not exceed the design limitations? 5. Is there a minimum of 6" clearance at the back and left side of the machine for proper service access and air circulation? (air cooled) 6. Is the water pressure a minimum of 20 psig? 2.
NSE650 START UP Pre-Start Inspection 1. Remove the front panels. 2. Check that the styrofoam shipping blocks have been removed. 3. Inspect the interior of the machine for loose screws or wires. Check that no refrigerant lines are rubbing each other. Check that the fan blade turns freely (air cooled). 4. Check that the unit is installed correctly according to the final check list (page 6). Start Up 1. Go through the prestart inspection. 2.
NSE650 COMPONENT DESCRIPTION Control Box: Contains the electrical controls that operate the machine. High Pressure Cut Out Switch: A manual reset switch sensing the high side refrigeration pressure. It is set to shut the machine off, and illuminate the reset switch light if the discharge pressure should ever exceed 450 psig. Compressor: The refrigerant vapor pump. Reservoir: Float operated, it maintains the water level in the evaporator at a constant level, it also contains the water level sensor.
NSE650 COMPONENT DESCRIPTION: Control Box Contactor: A definite purpose contactor connecting the compressor and the remote condenser fan motor to the power supply. Circuit Board: Controlling the ice machine through sensors and relays. The sensors are for ice level and water level. The relays are for the gear motor (with a built in time delay to clear the evaporator of ice when the unit turns off) and for the compressor. Transformer: Supplies low voltage to the circuit board.
NSE650 COMPONENT DESCRIPTION Evaporator: A refrigerated vertical tube filled with water and containing a water seal and auger. Auger: A solid stainless steel double spiral auger, it pushes the ice crystals up to the top of the evaporator. Water Seal: A two part "face" seal, the top half rotating with the auger, the bottom half stationary, the sealing action being where the two seal "faces" meet. Ice Sweep: A plastic cap with "fingers". It revolves with the auger to "sweep" the ice into the ice chute.
NSE650 ELECTRICAL SEQUENCE Refer the wiring diagram as needed. If the machine is switched off at the master switch, but is otherwise ready to go, switching the master switch to on does the following: • The bin empty light on the circuit board goes on • There is a 15 second delay • If there is enough water in the reservoir, the circuit board will allow the machine to start up.
NSE650 OPERATION: Water Reservoir overflow or evaporator condensation is routed to the drain. Water cooled models have a separate water circuit for the cooling water: it enters the fitting at the rear, goes to the water regulating valve, then to the water cooled condenser and down the drain. The storage bin has a separate drain tube and drain fitting.
NSE650 OPERATION: Refrigeration Beginning at the compressor, the refrigerant is compressed into a high temperature gas. The discharge line directs this gas to the condenser. At the condenser (air or water cooled) the gas is cooled by either air or water and it then condenses into a liquid. This high pressure liquid then goes through the liquid line to the expansion valve.
NSE650 TECHNICAL CHARACTERISTICS Typical Low Side Pressure • 32 - 34 PSIG, less in cooler ambients, greater in hot ambients Typical Discharge Pressure • 200 - 250 PSIG air cooled • 245 PSIG water cooled Typical Gearmotor Amp Draw • 3.1 -3.6 Typical Compressor Amp Draw • 8.5 to 9.
NSE650 MAINTENANCE AND CLEANING A Scotsman Ice System represents a sizable investment of time and money in any company’s business. In order to receive the best return for that investment, it MUST receive periodic maintenance. It is the USER’S RESPONSIBILITY to see that the unit is properly maintained. It is always preferable, and less costly in the long run, to avoid possible down time by keeping it clean; adjusting it as needed; and by replacing worn parts before they can cause failure.
NSE650 MAINTENANCE AND CLEANING 1. The bin control uses devices that sense light, therefore they must be kept clean enough so that they can "see". At least twice a year, remove the bin control sensors from the base of the ice chute, and wipe the inside clean, as illustrated. 2. The ice machine senses water level by a probe located in the water reservoir. At least twice a year, the probe should be removed from the reservoir, and the tip wiped clean of mineral build-up.
NSE650 MAINTENANCE AND CLEANING: Auger Moving Parts Hazard. Moving fan blade can cause personal injury. Disconnect electrical power before beginning. 5. Clean the air cooled condenser: Use a vacuum cleaner or coil cleaner if needed. Do NOT use a wire brush. Disconnect electrical power, and remove the filter. The filter may be cleaned or replaced. Clean the condenser: the condenser may appear to be clean on the surface, but it can still be clogged internally.
NSE650 SERVICE DIAGNOSIS: Condition - No Ice Being Produced STATUS: NOTHING OPERATES A. Check: Voltage to the unit, restore it if there is none. Compare to the nameplate. B. Check: The master switch, switch ON if off. C. Check: The reset switches, ( high and low pressure): depress and release each switch. If the machine still does not start, check: the high and the low side pressures. D.
NSE650 SERVICE DIAGNOSIS: Condition - No Ice Being Produced STATUS: NOTHING OPERATES G. Check: The gear motor, if it will not run, the compressor will not run. If no power to it: Check: The indicator lights on the circuit board, the bin empty light should be ON, the no water light should be OFF . 1. If the bin empty and no water lights are off, check the transformer. a. Transformer "load" side should have 12 to 15 volts. If not, check the "line" side. The line side should have 115 volts.
NSE650 SERVICE DIAGNOSIS: Condition - No Ice Produced STATUS: GEARMOTOR OPERATES, COMPRESSOR DOES NOT A. Check the compressor relay. The relay is on the circuit board, if it does not supply power to the contactor coil, the compressor will not run. 1. Check for power at the contactor coil, if none: a. Check for power at the compressor relay at the circuit board. If there is power at the relay, but none at the contactor coil, Check for an open wire between the relay and the contactor. 2.
NSE650 SERVICE DIAGNOSIS: Condition - Low Ice Production STATUS: EVERYTHING IS OPERATING A. Check the air cooled condenser for dirt. Clean as required. Check the head pressure on water cooled. Adjust as required. If the head pressure is very high: 1. Air cooled. Check for high air temperatures, or restrictive air flow. Correct as needed. 2. Water cooled. Check for high water temperatures, or low water pressure. Correct as needed. 3.
NSE650 REMOVAL AND REPLACEMENT: Water Reservoir & Bin Controls WATER RESERVOIR BIN CONTROLS (Ice Level Sensors) ICE LEVEL SENSORS: SLIDE UP TO REMOVE FLOAT ASSEMBLY PLUNGER LOCKING TAB 1. Shut off the water supply to the icemaker. 2. Remove front panel and reservoir cover. 3. Disconnect water inlet line from float valve. 4. To remove float only, push in the locking tab under the float valve, and pull float up and out of the reservoir. Note: an internal plunger is available separately. 5.
NSE650 REMOVAL AND REPLACEMENT: Bearing And Breaker Hazardous Moving Parts. Moving auger can cause personal injury. Disconnect electrical power before beginning. Note: Removal of the auger, water seal, evaporator and gearmotor must begin at the top of the assembly. To Remove the Breaker Bearing Assembly: 1. Remove top and front panels; disconnect electrical power. 2. Move bail clamp off ice chute cover and remove ice chute cover. 3. Unscrew and remove ice sweep. 4.
NSE650 REMOVAL AND REPLACEMENT: Auger Moving Parts Hazard. Moving Auger can cause personal injury. Disconnect electrical power before beginning. To Remove the Auger: Turn off the water to the machine, and unclip the evaporator drain hose, pull it down and drain the evaporator into the bin or a container. 1. The top panel must be removed. 2. Remove ice chute cover. 3. Unscrew ice sweep. 4. Remove ice chute body. 5. The auger and breaker/bearing may now be removed as an assembly. a.
NSE650 REMOVAL AND REPLACEMENT: Water Seal To Remove the Water Seal: (Assuming all steps to remove the auger have Sharp Parts Hazard. been performed.) Sharp auger edge can cause personal injury. 1. The gearmotor/evaporator Use gloves when handling auger. assembly will have to be exposed. 2. Remove the 4 hex head cap screws holding the evaporator to the gearmotor assembly. Lift the evaporator up and off of the gearmotor. 3. Remove the snap ring or wire retainer from the grove under the water seal.
NSE650 REMOVAL AND REPLACEMENT: Evaporator To Replace the Evaporator: (Assuming all the steps for removal of the thrust bearing, breaker, auger, and water seal have been performed.) 1. Recover the refrigerant from the ice maker. 2. Unsweat the refrigerant connections: a) At the thermostatic expansion valve outlet. //////////////////////////////CAUTION/////////////////////////// Heat sink the TXV body when unsweating or resweating the adjacent tubing.
NSE650 REMOVAL AND REPLACEMENT: Evaporator SEAL(S) O-RING EVAPORATOR BREAKER CAP SCREW ICE SWEEP WATER SEAL RETAINING RING O-RING DRIP PAN WATER SHED LIP SEAL GASKET BREAKER COVER WATER SHED O-RING GEARMOTOR ASSEMBLY AUGER STUD BEARING AUGER August 1993 Page 27
NSE650 REMOVAL AND REPLACEMENT: Gearmotor Electrical Shock Hazard. Electrical shock can cause personal injury. Disconnect electrical power before connecting tester. To Remove and Repair the Gearmotor Assembly: (Assuming that the procedures through removal of the water seal have been performed.) 1. Remove the electrical wires from the gear drive motor. 2. Unscrew the 4 cap screws holding the gearmotor to the base of the machine. 3. Remove the gearmotor from the icemaker.
NSE650 REFRIGERATION SERVICE: R-404A THIS ICE MACHINE USES R-404A (HP62) REFRIGERANT AND POLYOLESTER COMPRESSOR OIL. DO NOT USE MINERAL OIL IN THIS REFRIGERATION SYSTEM. • HP62 is a "Near Azeotrope", and therefore liquid charging is required. • When the system is serviced, a special liquid line dryer is required. • Polyolester oil absorbs water very easily, and therefore when the system is opened for service, it must be re-sealed as soon as possible (15 minutes maximum).
NSE650 REFRIGERATION SERVICE Recover, reclaim or recycle refrigerant. The General Information: method chosen is up to the service company. Any Work on the refrigeration system should only be refrigerant placed into a Scotsman ice machine done when it is certain that the system needs must meet ARI spec 700-88. Reclaim programs repair. are available through most refrigerant wholesalers. • Refrain from checking refrigeration Access Valves: To use the access valves: pressures without reason.
NSE650 CIRCUIT BOARD TESTING Electrical Shock Hazard. Electrical shock can INSTRUCTIONS FOR USING TESTER (Optional, cause personal injury. order part no. A33942-001) Disconnect electrical power before connecting (These instructions assume that the unit will not run, and prior investigation of electric power, controls, and tester. mechanical parts indicates that the electronic circuit may be at fault.
NSE650 CIRCUIT BOARD TESTING Water Level 1. Unplug “water sen” connector from control board. 2. Plug “water sen” connector from Scotsman tester into circuit board. a. Move “water” switch on tester to No Water position. The No Water light on the circuit board should go ON. If not, replace the circuit board. b. Move the “water” switch on the tester to the Water position. The No Water light on the board should go OFF. If not replace the circuit board. If the light does go off, replace the water level sensor.
