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 . [. . . ] At least twice a year, the probe should be removed from the reservoir, and the tip wiped clean of mineral build-up. 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 grommets in the ice chute, and wipe them clean. The bearing in the breaker should also be checked at least two times per year. Check the bearing by: ·removing the ice chute cover ·unscrewing the ice sweep ·removing the water shed ·unscrewing the breaker cover. ·unscrewing the auger stud See Removal and Replacement to replace bearing or seals. Check and tighten all bolts and screws. April 1997 Page 19 NDE550 & NDE650 MAINTENANCE AND CLEANING In some areas, the water supply to the ice maker will contain a high concentration of minerals, and that will result in an evaporator and auger ALLEN HEAD SCREWS Moving Parts Hazard. Disconnect electrical power to the icemaker dispenser before beginning. BREAKER AND AUGER ASSEMBLY becoming coated with these minerals, requiring a more frequent removal than twice per year. If in doubt about the condition of the evaporator and auger, the auger can be removed so the parts can be inspected. Note: Water filters can filter out suspended solids, but not dissolved solids. For more information on removal of these parts, see REMOVAL AND REPLACEMENT. After the auger has been removed, allow the auger to dry: if the auger is not bright and shiny, it must be cleaned. Reverse to reassemble. April 1997 Page 20 NDE550 & NDE650 SERVICE DIAGNOSIS: Condition - No Ice Being Produced STATUS: ICE MAKER DOES NOT OPERATE A. 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. 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. [. . . ] (DEG F) 70 72 74 76 78 80 82 84 86 88 90 92 94 96 98 100 102 104 106 108 110 112 114 116 118 120 122 124 126 128 130 132 134 136 138 140 142 144 146 148 VAPOR PRESSURE (PSIG) 146 150 155 161 166 171 177 182 188 194 200 206 212 219 225 232 239 246 253 260 268 275 283 291 299 307 316 324 333 342 351 360 370 379 389 399 409 420 430 441 April 1997 Page 32 NDE550 & NDE650 REFRIGERATION SERVICE General Information: Work on the refrigeration system should only be done when it is certain that the system needs repair. Visual inspection of the water system, observation of the ice formation, amp draw, voltage, and other techniques will lead to proper diagnosis. Scotsman also recommends that, at the time of initial start up, gauges not be used. Any refrigerant placed into a Scotsman ice machine must meet ARI spec 700. [. . . ]