User manual SCOTSMAN NM650

[. . . ] NM650 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 NM650 is a modular ice system that fits a variety of Scotsman ice storage bins. It features: front service for the freezer, gearmotor, control box, water reservoir, and bin control; an electronic circuit for monitoring ice and water level; a thermostatic expansion valve; and R-502 as the refrigerant. TABLE OF CONTENTS Installation For the Installer Specifications . 4 Two units on one bin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 For the Plumber . [. . . ] Check with a flash light from the front to see if light can be seen though the condenser fins. Step 2: Remove the top portion of the fan shroud. Step 1: Remove the top panel. Step 3: Clean the condenser. January, 1991 Page 18 NM650 MAINTENANCE AND CLEANING: Auger /////////////////////////////WARNING/////////////////////////// Disconnect electrical power. ///////////////////////////////////////////////////////////////////////// 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 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. Remove 3 hex studs holding ice chute cover to ice chute, and remove cover. Loosen band clamp under ice chute, and remove ice chute from evaporator. After the auger has been removed, allow the auger to dry: if the auger is not bright and shiny, it must be cleaned. 1991 production, removal of the chute cover requires pulling the bail out of the notch in the chute cover. Also the breaker cover will not require a spanner wrench to remove it. Breaker Cover ALLEN SCREWS BREAKER & BEARING & AUGER ASSEMBLY Bail/Clamp January, 1991 Page 19 NM650 SERVICE DIAGNOSIS: Condition - No Ice Being Produced STATUS: NOTHING OPERATES A. Check: Older models (late 1990 production and earlier) the 3 reset switches, (circuit board, high and low pressure): depress and release each switch. If the still does not start, check: the spout switch; the high and the low side pressures. Current models: there is no reset on the circuit board, reset the high, low and spout switches. Check the low pressure cut out, if closed, go to E; if 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 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. [. . . ] Unscrew the 4 cap screws holding the gearmotor to the base of the machine. Bench test the gearmotor, check for oil COVER & leaks, noise, and amp draw. ASSEMBLY A) Remove the cap screws holding the gearmotor case halves together and pry the two cases apart. B) To lift off the cover, lift up until you can feel internal contact, then pull the cover towards the output gear end, and then lift the cover (with drive motor attached) up and away from the gear motor case. [. . . ]