User manual SCOTSMAN C2648 SERVICE MANUAL 11-2010

[. . . ] C2648 Service Manual Introduction The design of this modular remote cuber is the result of years of experience with remote ice machine refrigeration systems. Standard features of this product include front accessible on-off switches, always-visible indicator lights, mechanical assist ice harvest for extra efficiency, automatically adjusting water purge and a control system that optimizes system operation. The manual includes installation information, technical details, diagnostics and service parts. Note the Caution and Warning symbols when they appear on the product or in this manual. [. . . ] The hot gas valves and the harvest assist solenoids are energized by the High Capacity Relay. When the reservoir is full the inlet water valve stops, the liquid line valve is opened and the compressor switches on. Five seconds after the compressor starts the hot gas valve and the harvest assist solenoid are de-energized. The compressor, fan motor, water pump, sump full lights will be ON and all curtain switch lights will be OFF. When the reservoir water temperature falls to a certain preset point, the water pumps will shut off for 30 seconds. At this time the controller checks the conductivity of the water in the reservoir for the auto-purge feature. After the water pumps restart the Sump Full light will go out and neither sump lights will be on for the rest of the freeze cycle. When the ice has built up enough so that the water flowing over the evaporator comes into continuous contact with the ice level sensor, the Ready to Harvest light will begin to blink on and off. When it has been On continuously for 3 seconds, the controller will switch the machine into a Harvest cycle. After a few seconds the water pump, purge valve and inlet water valve lights will switch on. The three harvest assist solenoids are connected in parallel with the three hot gas valves. Although energized throughout the harvest cycle, a harvest assist piston does not move until the ice has become partially loosened from the evaporator plate by the action of the hot refrigerant gas passing through the evaporator serpentine. November 2010 Page 6 C2648 Service Manual The remote condenser fan motor is powered by the compressor contactor, so it will be operating during the harvest cycle. The operating water pump and purge valve will shut off when the purge level setting time has been reached, either the manual time or the automatic time. The Ready to Harvest light will switch Off when the ice falls from the evaporator. Harvest continues until the ice slab is ejected from the evaporator and falls, opening the curtain. When the curtain opens, the magnetic reed curtain switch opens, breaking the circuit to the controller. If all the curtains re-close within 30 seconds, the controller switches the machine back into another freeze cycle. If any curtain switch remains open, the controller shuts the machine down and puts it into a standby position. November 2010 Page 7 C2648 Service Manual Electrical Component Details Compressor · Operated by the compressor contactor. Contactor · Operated by the controller and the high pressure cut out switch. When energized the Compressor indicator light will be ON. Water Pumps · Operated by the controller, one of them thru a NC relay. When the Pump light is ON during a Freeze cycle, both pumps should be operating. When the Pump and Purge lights are both ON, one pump will be ON and one will be OFF. Inlet Water Solenoid Valve · Operated by the controller. [. . . ] 19 Return front panel to its original position. November 2010 Page 50 C2648 Service Manual Vari-SmartTM Adjustable ice level option The adjustable ice level control is an optional add-on system consisting of an control board, label and sensor. The control board fits above the standard control and connects to it using connector J4. The sensor mounts to the base of the ice machine through a hole in the base. Rotating the knob CW lowers the maximum ice level that the ice machine will maintain in the bin or dispenser. [. . . ]