Service; Icemaker Operation; The Icemaking Process; Ice Harvest System Diagram - Follett Symphony 25HI400A Installation & Service Manual

Service

Icemaker operation
Follett's icemaker consists of four distinct functional systems:
• Refrigeration system
• Water system
• Harvesting system
• Electrical control system
These four systems work together to accomplish the production and harvesting of ice. A problem in any one of these
systems will result in improper operation of the entire ice production cycle. When troubleshooting the icemaker, it is
important to analyze the entire system operation to determine which system is not functioning properly, then pinpoint
the component within that system that is malfunctioning. Determine what corrective action must be taken before
making any adjustments or replacing any components.
The icemaking process
The Follett icemaker uses a stainless steel jacketed evaporator and operates on a continuous freezing cycle.
Water is supplied to the evaporator from the water reservoir where the water level is controlled by a float valve.
This valve also shuts off the water supply when the icemaker is not running.
When the icemaker is running, a layer of ice
forms on the interior surface of the evaporator.
This ice is continuously removed by a slowly
rotating (12 RPM) auger.
The auger carries the ice upward into the cavity
formed by the top bearing housing and the
compression loop, where it is compressed to
remove excess water.
When the ice reaches the desired hardness it
rotates within the cavity and is forced through
a discharge port and compression nozzle and
into the ice transport tube. The discharge tube
and compression nozzle are slightly restricted
to further compress the ice and produce the
desired hardness. As the formation of ice
continues, ice in the transport tube is pushed
through the tube to the storage compartment in
the ice dispenser.
A solid state control board, located in the
electrical box of the icemaker, controls the
normal operation of the icemaker and monitors
gearmotor torque. This control board will shut
down the icemaker should an over-torque
condition occur. It is very important that
you familiarize yourself with the operational
sequences detailed in this manual before
attempting to service the icemaker.
25CI400A/W • 25HI400A • 50CI400A/W • 50HI400A
Ice harvest system diagram
water
inlet
discharge
port
ice transport tube
compression nozzle
auger
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