Technicians Only: Harvest Cycle Operational Sequence - Scotsman CME256 Product Manual

Technicians Only: Harvest Cycle Operational Sequence

Harvest
The (air cooled model) fan is off.
The water valve opens and fills the reservoir to the
Full level.
The water pump shuts off, it will restart in less than
a minute.
Note: Machines built after August 1996:
•
If the machine remains in the harvest cycle
for longer than between 6 to 9 minutes
(depending upon the regular harvest cycle's
length) the water pump will be switched off
until the next freeze cycle.
•
When the bin is full and the unit is in a
harvest cycle, the pump will be switched off.
The 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 time between restarts is about 20
minutes.
The inlet water valve will stay on and open for a
predetermined fraction of the time it took to fill the
reservoir. This overflows and rinses the reservoir
water.
During the Harvest Cycle, ice will be falling from
the evaporators and between the bin control's
electric eyes. The Controller monitors the ice
falling and stays in the Harvest Cycle until ice quits
going thru the electric eyes.
The maximum harvest time is 10 minutes. The first
Harvest after a restart will be a long one to
establish a base line, then the actual time it took to
release the ice is used to determine the length of
the next harvest cycle.
If no cubes fall (or are sensed) by the end of
Maximum Harvest Time, the machine senses a
refrigeration error. If the next cycle also produces a
refrigeration error, the machine Shuts Down.
Note: Machines built up to August 1996: The last
Harvest cycle before shutting off on Bin Full will be
10 minutes long. Machines built beginning
August 1996 have a last harvest cycle that is
4-6 minutes long.
Note: The machine will not restart for 4 minutes
after switching off on Bin Full, unless the freeze
button is pressed.
CME256, 506, 656, 806: AutoIQ™ Cubers
Stacked Units:
If the bottom unit is in harvest and receives a
signal from the top unit that it is also in Harvest,
the bottom unit will stay in harvest for its Maximum
Harvest Time.
Diagnostic Lights and Manual Resets
The controller will shut the machine off if a
malfunction is sensed. Controllers up to 17-1 will
shut the machine off after the first malfunction.
Controllers marked 17-1 and up will restart the
machine 2 times, with a 50 minute interval
between restarts.
If a malfunction is still present after the second
restart, the machine will then shut off and must be
manually reset. During the restart interval, the
machine will be off and a diagnostic code
indicated.
An exception to this is lack of water. When
switched off because of lack of water, the machine
will always try to re-fill the reservoir every 20
minutes.
Another exception is a harvest error. As before,
there must be two consecutive harvest errors to
trigger a machine shut-down. With this change, the
controller will still shut down and restart the
machine after two consecutive harvest errors.
However, if the errors repeat two more
consecutive times, the controller will shut down
and restart the machine again. If the machine
registers two more consecutive harvest errors, the
machine will again shut down and must be
manually reset.
Production of units with Controllers 17-1 began
approximately March 1997. Higher numbers may
be expected after that date.
January 2002
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