Scotsman NU150 Service Manual page 20

NU Undercounter Ice Machine Service Manual
Water Level Sensor
The water level sensor is located at the top of
the water tank. When water level reaches a
certain level during water filling, the magnetic
sensor of the water level sensor detects the
magnetism and signals it to the PC board.
Once the PC board receives the signal, then it
will power off the water inlet valve and water
filling is stopped.
The water level sensor is installed on the
support of water level sensor and can be
adjusted.
Note:
When the water level in the water tank is
considered to be too high and water
overflows whenever water is filled, it is
means that the water level sensor cannot
control the water inlet valve, the position of
the water level sensor can be adjusted lower.
If the position of the water level sensor is
adjusted low and the problem is not solved, it
means that the water level sensor is failure
and should be replaced.
Vertical Type Water Spray System
The water pump spray out the water sucked
from the water tank. The water flow into the
spray tube through the PVC tube, then pass the
pinholes on the water tube, and then flow
evenly through the ice molds of the evaporator,
thus ice cubes are made. It is cycled
continually.
Water pump
The water pump
throughout the freezing cycle and keeps water
flowing continually through the ice molds of the
evaporator and produces ice cubes.
operates continually
Recommendation:
The water pump should be checked at least
every 3 months.
Water Inlet Solenoid valve - 3/4" Male Fitting
The water inlet solenoid valve is located on the
up and down water support. The incoming
water is controlled by the PC board, among
which one water flow controller is used to
control the water flow incoming the water tank.
Defrost Solenoid Valve
The defrosting solenoid valve, located at the
hot gas bypass tube, is consisted of valve body
and coil. During defrosting and water filling
period, operation is controlled by the PC board.
During the defrost cycle, the defrost solenoid
valve is energized and sucks the push rod of
the valve body in order to let the hot gas
discharged from the compressor to flow directly
into the evaporator pipe to melt the formed ice
cubes.
Fan
The Fan is controlled by PC board to draw
cooling air through the condenser fins, thus to
lower the discharge temperature of the
compressor. Normally it operates
only during the freezing cycle to keep the
condenser pressure
corresponding pressure values.
Compressor
The hermetic compressor is the heart of the
refrigerant system of the ice machine and it is
used to circulate and retrieve the refrigerant
throughout the entire system.
It compresses the low pressure refrigerant
vapor causing its temperature to rise and
become high pressure hot vapor which is then
released through the discharge valve and then
will reach the condenser.
Water Drain Solenoid Valve
The water drain solenoid valve is controlled by
the PC board.
configuration of the PC board(Drainage is set
behind one ice freezing cycle, which is set by
factory), it starts operating for 30 seconds so
that all remaining water containing minerals in
the water tank drains out.
19
Components Description
intermittently
between
Based on the different
two