User manual SCOTSMAN SCE275

[. . . ] SCE275 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 repair this product. The SCE275 is an ice machine that produces cubed ice on a vertical freezing surface. The cubes fall into the ice storage bin where they break up into individual cubes. The SCE275 automatically maintains the level of ice by turning on when the ice level falls, and switches off when the bin is full. [. . . ] If the discharge temperature is acceptable, the water system is checked by shutting off the water pump and determining if the water level goes up enough. If it does not, it is assumed that there is a water pump problem and the machine Shuts Down on a Water Error. If the water level does "measure up" the water pump is restarted and the AutoIQ Controller then measures how long it takes to lower the water level. If the water level does not fall, the machine Shuts Down on a Water Error. It only does this when the water temperature reaches a preset minimum. After the pump restarts, the inlet water valve opens to refill the reservoir. When the water level falls to the pre-set limit, the inlet water valve will open to refill the reservoir. As the machine makes ice, the water level in the reservoir will ultimately fall a third time to the Harvest Level (when the top electric eye in the water level sensor is disrupted by the adjustment screw). At that point, the fan may be shut off and the unit continues in a freeze cycle for a few more seconds (0-60 depending upon discharge temperature). Note: If the freeze cycle exceeds the preset Maximum of 35 minutes, the AutoIQ Controller will Shut Down on a Refrigeration Error. The end of Freeze cycle will see the machine in this state: Water level = below harvest position Condenser fans will be off Water inlet valve will be off Water pump will be ON Compressor will be ON Hot gas valve will be off At this point Harvest begins and the AutoIQ Controller switches the Harvest indicator light ON. Note: If there is a power interruption, the AutoIQ Controller will automatically restart the machine with a process that begins with returning the machine back to a normal state: water re-fills the reservoir, the unit freezes for 30 seconds, and then goes thru a 4 minute harvest. While in this electrical restart mode, the controllers Freeze light will be blinking, even when it is in a Harvest cycle. January 2003 Page 18 SCE275 Technicians Only: Harvest Cycle Operational Sequence Harvest The (air cooled) fans are off. The AutoIQ Controller checks how long it takes to fill the reservoir and if it was too much time, the machine Shuts Down on Water Error. Note: The machine will automatically attempt to restart after shutting down because of a lack of water. The inlet water valve will stay on and open for a predetermined fraction of the time it took to fill the reservoir. During the Harvest Cycle, ice will be falling from the evaporators and between the bin control's electric eyes. The harvest cycle's length is based on the actual time from the start of the prior harvest cycle until the last cube fell, plus an added amount of time as a margin. Harvest time is varied by the AutoIQ Controller based on the prior harvest cycle's length. If no cubes fall (or are sensed) by the end of Maximum Harvest Time, the controller senses a refrigeration error. If the next cycle also produces a refrigeration error, the machine Shuts Down. Note: The last Harvest cycle before shutting off on Bin Full will be longer than normal (4-5 minutes). [. . . ] Remove the insulation covering the thermistor and un-clip it from the discharge line. Route the thermistor to the discharge tube of the compressor and attach it to the discharge line in the same place as the original. At the upper left of the machine, un-plug the water pump and water level sensor. Lift up the water pump mounting plate and pull the water hose off the water pump. [. . . ]