User manual SCOTSMAN CMS1202R

[. . . ] CMS1202R INTRODUCTION To the owner or user: This service manual 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. Table of Contents Specifications . For the Installer Location & Assembly Stacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4 7 8 9 10 12 13 15 17 19 20 21 25 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . For the Electrician For the Plumber Final Check List Initial Start Up . [. . . ] after that selected length of time, the timer will switch the icemaker into the harvest cycle, through the contacts of the timer assembly microswitch. Low Temperature Freeze: When the outside air temperature is low, the Head Pressure Regulator will close off the liquid line to the receiver, causing liquid refrigerant to back up into the condenser unitl the head pressure builds up to 220 PSIG. While this is occuring, the head pressure regulator passes discharge gas into the receiver to keep the refrigerant flowing. WATER DISTRIBUTION INLET WATER VALVE DRAIN RESERVOIR WATER SCHEMATIC REFRIGERATION SCHEMATIC September 1993 Page 12 CMS1202R HARVEST CYCLE - HOT GAS BYPASS When the timer switches the icemaker into the harvest cycle, high pressure, high temperature gas refrigerant being discharged from the compressor is diverted from the condenser through the hot gas solenoid valve into each evaporator plate. ln the electrical circuit, both the compressor and the water pump are operating and the hot gas solenoid valve is energized and OPEN and the water inlet solenoid valve is OPEN. The finished ice cubes are released from the sides of each evaporator plate by the warming effect of the hot gas condensing in each evaporator plate and the water cascading over the ice cubes. At the end of the harvest cycle, the timer cam will push the actuator arm to the microswitch IN. If the ice level control is still CLOSED, a whole new cycle will begin. If the ice level control is OPEN, the icemaker will begin to shut OFF. Pump Down Cycle: When the ice level control is open at the end of the harvest cycle, power is removed from the liquid line valve coil, and the pump down cycle begins. The compressor will continue to run until the pump down control, sensing low side pressure, opens at 20 PSIG. WATER DISTRIBUTION INLET WATER VALVE DRAIN RESERVOIR WATER SCHEMATIC REFRIGERATION SCHEMATIC September 1993 Page 13 CMS1202R COMPONENT DESCRIPTION Cube Size Control This reverse acting thermostat controls the length of the freezing cycle. When the suction line gets cold enough, the cube size control closes (on temperature fall) and starts the timer. A change in either ambient air or incoming water temperature will affect the efficiency of the refrigeration system, and this will vary the length of time it takes the evaporator to reach the temperature at which the cube size control is preset to close. Relay The multi-function, three pole, double throw, plug-in relay is installed directly into a receptacle on the printed circuit board in the control box. The relay functions in part to by-pass the bin thermostat control to prevent the icemaker from shutting OFF, when the bin thermostat opens during the freezing cycle. The bypass action serves to ensure full-sized ice cubes with each harvest cycle. Timer - Timer & Switch Assembly The function of the timer begins when activated by the cube size control. The outer surface, or large diameter lobe of the timer cam, determines the timer cycle for finish freezing of the ice cubes, while the inner surface, or small diameter lobe, determines the time cycle for the harvest cycle. When the microswitch button is pushed in there is power connected to the coil of the relay, and the unit is in the freeze cycle. When the microswitch button is released, the power to the relay is stopped, and the unit goes into harvest. The microswitch is actuated by a cam assembly directly connected to the timer motor. High Pressure Safety Control This is a manual reset control that shuts down the icemaker, should the discharge pressure ever reach 400 PSIG. Low Pressure Control (Pump Down) This pressure control connects power to the compressor contactor coil. [. . . ] Unsnap and disconnect water distributor tubes from the water manifold section. To replace the water distributor tubes and manifold tubes, reverse the removal procedure. BE SURE the notches in the water manifold tubes properly engage the alignment keys in the tee. BE SURE the water distributor tube is securely fastened at the notch at both sides of the evaporator plate. [. . . ]