User manual SCOTSMAN NDE650

[. . . ] NDE550 & NDE650 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 maker-dispenser. This machine is a combination nugget ice maker and countertop dispenser, with the option of wall mounting. The ice making section is equipped with the following features: electronic controls for bin level and low water; thermostatic expansion valve; front service for most components; and R-404A (HP62) refrigerant. The ice dispensing section is a seamless plastic storage bin, with a stainless steel rotating vane to sweep the ice into the dispensing chute. Table of Contents FOR THE INSTALLER: Specifications . [. . . ] "Soft" water may not be the complete answer. Check with a water treatment specialist regarding water treatment. For more information on removal of these parts, see REMOVAL AND REPLACEMENT. To remove the auger, remove the front and top panels. Push bail clamp off of cover and remove cover. Remove 4 allen screws holding breaker to evaporator. After the auger has been removed, allow the auger to dry: if the auger is not bright and shiny, it must be cleaned. Clean the auger and evaporator as required. Reverse to reassemble. April 1997 Page 20 NDE550 & NDE650 SERVICE DIAGNOSIS: Condition - No Ice Being Produced STATUS: ICE MAKER DOES NOT OPERATE A. Check: Voltage to the unit, restore power if there is none. Check: The master switch, switch ON if off. 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. Check the low pressure cut out, if closed, go to E; if it is open, it could be due to: ·Low refrigerant charge ·The auger not turning ·Restricted system ·TXV not opening 1. Check the low side pressure, the low pressure cut out opens at pressure below 4 psig. Check if the auger is turning, if it is not, remove the gearbox and: Check for internal damage, repair and replace in the machine. Check for low charge, add some refrigerant, if the unit will operate, (normal low side pressure being about 38-40 psig) stop and look for a leak, repair, replace the drier, evacuate, and weigh in the nameplate charge. If, with added charge, the unit does not operate: Check for a restricted system, replace the drier, evacuate, and weigh in a nameplate charge. Check for a Thermostatic Expansion Valve that does not open, if defective, replace it. Replace the drier, evacuate, and weigh in the nameplate charge. E. Check the high pressure cut out, if closed, go to F; if open: 1. Check the high side pressure, reset the control, and observe: on water cooled, that water soon begins to flow from the condenser drain; or, on air cooled, that the fan is forcing air through the condenser. [. . . ] If the condenser is clean and seems to be operating correctly, it most likely is. The low side pressure is more important on an ice machine than the high side. ·If gauges must be used, use very short hoses to minimize refrigerant discharged into the air. Allen Wrench ·Refrigerant should not be added except as a way to determine the proper operation of the product. If the system was low on refrigerant, there is a leak, and it must be found and repaired. Torque Stem to 6-8 ft. lb. ·This system has a critical charge, it must be recharged with the correct amount of refrigerant as listed on the nameplate of the ice machine, or performance will suffer. ·Anytime the refrigeration system has been opened, the dryer should be replaced. [. . . ]