Service Information; The Icemaking Process - Follett Symphony 12 Series Installation, Operation And Service Manual

Service
Important preliminary information
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 system areas 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.
Note: When performing electrical service, always use a meter to determine whether or not components being
serviced are energized.

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 fl oat 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 high quality. As the formation of ice continues, ice in the transport tube is pushed through
the tube to the storage compartment in the ice dispenser or ice storage bin.
A solid state control board located in the electrical box of the icemaker controls the normal operation of the icemaker
and monitors gearmotor torque on an ongoing basis. 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.
Access to electrical box and control board
The 12 series electrical box has been designed to slide out
for easy access to the control board and more convenient
troubleshooting.
1. Remove top and front panels of dispenser (for panel
removal instructions see page 30).
2. Remove electrical box cover.
3. Pull electrical box toward front of unit.
electrical box
electrical box
cover
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