User manual SCOTSMAN NME1250

[. . . ] NME1250 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 NME1250 features: front service for the evaporator, gearmotor, control box, water reservoir and bin control; electronic circuitry for monitoring ice and water level; a thermostatic expansion valve; and HP62 as the refrigerant. TABLE OF CONTENTS FOR THE INSTALLER . 24 REMOVAL AND REPLACEMENT: Water Seal REMOVAL AND REPLACEMENT: Evaporator . 30 Parts Lists and Wiring Diagrams are located in the center of this manual, printed on yellow paper. Note this symbol when it appears. This manual was printed on recycled paper. [. . . ] Handle auger with care, it has sharp edges. Air Cooled Models: Clean the Air Filter and Condenser as needed to keep the machine operating efficiently. Check the fins for dirt, clean as needed until light can be seen through the condenser. Replace panel and reconnect power. August 1993 Page 17 NME1250 SERVICE DIAGNOSIS: Condition - No Ice Being Produced STATUS: NOTHING OPERATES A. Check: The reset switches, (high and low pressure): depress and release each switch. If the 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 30-32 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 pressure cut out, if closed go to F, if open check: 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 unit trips out on pressures below 450 psig, replace the control. If the pressures rise above the trip out point, and the unit shuts down: a. Check for adequate water flow on water cooled, if adequate, clean the interior of the condenser. If the pressures are still too high replace the water regulating valve. If the air flow is poor because of the installation, advise the user that the unit should be moved, or the air around it kept cooler. Check that the fan blades are clean, and the fan secure to the fan motor shaft. F. The machine will not run if there is not enough water in the reservoir. 1. See the next step. June 1994 Page 18 NME1250 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. [. . . ] 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. · Refrain from checking refrigeration Access Valves: To use the access valves: pressures without reason. Visual inspection Remove the cap from the stem, use a 3/16" allen of the water system, observation of the ice wrench to check that the valve is CLOSED. Close the valve and replace the caps when the Scotsman also recommends that, at the time of job is finished. [. . . ]