Manitowoc Ice QF0400 Ice Maker User Manual


 
Part Number 000002688 4-1
Section 4
Ice Machine Sequence of Operation
QF400/QC700/QF800
PRIOR TO START-UP
When the toggle switch is placed in the “ice” position the
following must occur prior to starting an ice making
cycle.
A. The bin level probe must be open (bin level
light off). If the probe is closed, (bin level light
on) when the toggle switch is moved to ICE, the
control system waits until the bin level probe
opens, (bin level light off) before starting an ice
making sequence. If the bin level probe is
removed/disconnected the ice machine will not
start.
B. The water level probe must be closed (water
level light on) to start the compressor. If the
water level probe is open, (water level light off)
the control system waits until the water level
probe closes before starting the compressor.
INITIAL START-UP
1A. Flush
Immediately after placing the toggle switch into ICE, the
dump valve solenoid, and gearbox are energized. After
45 seconds the dump valve de-energizes.
1B. Water Fill
After 45 seconds the water float valve solenoid is
energized.
2. Freeze Cycle
When water contacts the water level probe, the
compressor and condenser fan motor energize
(condenser fan motor is wired through a fan cycling
control).
The gear motor, compressor, condenser fan motor and
water float valve solenoid remain energized as the ice
machine makes ice. The water float valve will open and
close automatically to maintain the proper water level.
AUTOMATIC SHUT-OFF
3A. Ice Run Out
Ice will build up in the bin until it contacts the bin level
probe. After ice contacts the bin level probe for 30
continuous seconds the compressor de-energizes. To
allow excess ice to run out, the gear motor and the water
float valve solenoid remain energized for an additional
45 seconds, then de-energize.
3B. Water Drain
To allow water to drain from the evaporator, the dump
valve energizes for 90 seconds, then de-energizes.
An 8-minute lockout starts when the compressor de-
energizes. When the ice drops away from the bin level
probe the ice machine will begin an initial start-up cycle,
provided the “8-minute lockout” has expired.
8 Minute Lockout
The bin level light will flash until the 8-minute lockout
expires.
After the 8 minute lockout expires the bin level light will
de-energize.
The 8 minute lockout time can be overridden by moving
the ON/OFF/CLEAN toggle switch from ICE to OFF then
back to ICE.
FLUSH SEQUENCE IN THE “ICE” POSITION
After the ice machine has run for 100 hours the ice
machine will stop making ice and perform a flush
sequence. The flush sequence will remove minerals that
have settled in the bottom of the evaporator. The entire
flush sequence lasts approximately 11 minutes, after
which the ice machine automatically resumes ice
making and the 100 hour counter in the control board
resets to zero.
NOTE: Flake ice machines use an auger to remove ice
from the evaporator. Occasional noises (creaks, groans,
or pops) are a normal part of the ice making process.