Sub-Zero 3 1 5 I Installation & Operation Manual page 16

S U B - Z E R O
I C E
Ice production has two distinct cycles: freeze
and harvest. One freeze cycle and one harvest
cycle will yield a batch of eight ice cubes.
The freeze cycle occurs when water is sprayed
against the freezing surface. The harvest cycle
occurs when the ice is released and water
enters the ice maker. A complete cycle takes
about 30 minutes.
F R E E Z E C Y C L E
During the freeze cycle the compressor is
pumping refrigerant, the fan motor is blowing
air, and the water pump is circulating water. As
the refrigerated surface absorbs heat from the
water sprayed against it, that heat is moved to
the area where the fan is blowing air. The heat
is transferred to the air, and the warmed up air
is discharged from the ice maker. At the same
time, ice is forming on the refrigerated surface
(located at the upper back of the ice maker).
When the refrigerated surface gets cold
enough, the ice maker's timer will begin to
turn. When it turns far enough, it will stop the
freeze cycle and begin the harvest.
H A R V E S T C Y C L E
During the harvest cycle the compressor is still
operating, but the spray pump and fan motor
have stopped. Two other components have
been energized: the hot gas valve and the inlet
water valve. These two valves open and warm
up the freezing surface, allowing the cubes to
fall into the ice storage bin. The timer is still
turning, and when it gets to the end of the
harvest cycle, the freeze cycle will restart.
16
M O D E L S 3 1 5 I
P R O D U C T I O N
A N D 3 1 5 I P O P E R AT I O N
H O W T H E I C E M A K E R U S E S W AT E R
The ice maker begins with a fixed charge of
water that is contained in the reservoir. As the
water is sprayed against the freezing surface,
the part of water that does not contain mineral
impurities will freeze and stick to the ice cup
molds. The water containing impurities falls
back into the reservoir. Gradually, during the
freezing portion of the ice making cycle, the
water in the reservoir will become highly
concentrated with mineral impurities.
During the harvest cycle fresh water flows into
the ice maker to dilute the reservoir water and
to rinse the concentrated minerals down the
drain.