Page 19
Page 19
HARVEST (DEFROST) CYCLE
REFRIGERATION SYSTEM SCHEMATIC
REFRIGERATION SYSTEM DURING
HARVEST
The refrigeration system performs the harvest of
ice by use of a hot gas bypass valve. When the
time comes to de-ice the evaporators, the hot
gas valve is energized, and the high temperatu-
re, high pressure gas bypasses the condenser,
and is allowed directly into the evaporator. The
high pressure gas is cooled by the cold evaporator
so it condenses into a liquid, giving up its heat as
it does so. This heat warms the evaporator and
the ice frozen onto the evaporator surface melts,
releasing the frozen cubes. Ice then falls by
gravity into the storage bin.
The liquid refrigerant goes through the suction
line into the heat exchanger where it boils-off so
that only refrigerant vapor is drawn into the
suction tube of the compressor.
WATER SYSTEM
During the harvest cycle, the electric water
drain valve is energized thereby opening the
drain line.
All water remained in the reservoir at the end of
freezing cycle is pumped-out, to the waste,
through the water solenoid and drain line during
the first 20 seconds of the defrost cycle eliminating
any possible build-up and accumulation of
minerals concentration and impurities in the water
reservoir.
As the pump stops, the incoming water, passing
through the float valve, has still sufficient time,
before the beginning of the next start up of the
water pump, to properly fill up the sump/reservoir,
so that there would not be any cavitation problem
when the water pump will resume its operation.
This grants a better ice formation inside the
cooling cells.
When the released ice cubes drop into the bin,
they open-up for a fraction of a seconds the
bottom end of plastic deflector.
This deflector swinging motion is enough to reset
the contact of the magnetic switch which - via
electronic control board - deenergizes the water
drain valve allowing the unit to initiate a new
freezing cycle.
