Scotsman AC 105 Service Manual page 20

The DIP SWITCH first four keys setting
determines the length of the 2nd phase of
TAB. B
LENGTH OF TIMED PORTION OF FREEZING CYCLE ACCORDING TO THE
The DIP SWITCH keys 5 & 6 setting determines
the length of the defrost cycle according to the
size of the cubes (Large or Medium). It is not
possible to modify the length of the defrost cycle
(factory setting).
The 7th D.S. key is not used in this release of the
P.C. BOARD.
The 8th DIP SWITCH key allows to make a rapid
check up of the P.C. BOARD output connections
(compressor, water pump, fan motor, water inlet
and hot gas solenoid valves) energizing them in
rapid sequence (2 seconds) one by one.
DURING THE AUTOMATIC OPERATION OF
THE ICE MAKER THIS KEY MUST BE SET IN
OFF POSITION.
ATTENTION. The check up of the
P.C.BOARD output must be performed in
a very short time in order to avoid frequent
start and stop (every few seconds) of the
electrical components which may damage
them specially the compressor.
The 9th key allows the operation of the water
pump even during the defrost cycle, as required
when it is necessary to drain out the remaining
water from the sump.
The 10th key is used to supply power to the
water pump for the first 15 seconds of the defrost
cycle - position OFF - and for the first 30 seconds
- position ON.
F. WATER SPRAY SYSTEM
Through its nozzles, the water pumped, is sprayed
in each individual cup to be frozen into ice.
It consists of one spray tube wheve are located
several spray nozzles.
G. WATER PUMP
The water pump operates continually throughout
the freezing cycle and on the first 15 or 30
freezing cycle (controlled by the electronic
timer) as detailed in the table B.
DIP SWITCH SETTING COMBINATIONS
seconds of the defrost cycle so to such the
remaining water from the sump tank (reach in
mineral salts) and drain it out.
During the freezing cycle the pump primes the
water from the sump to the spray system and
through the spray nozzles sprays it into the
inverted cup molds to be frozen into crystal clear
ice cubes.
It is recommended that the pump motor bearings
be checked at least every six months.
H.
A special water inlet solenoid valve with one inlet
and two outles (one for condenser and the second
for the production of ice) is used on water cooled
version.
An automatic hi pressure control activates the
second coil of the water inlet solenoid valve so to
supply a metered amount of water to the
condenser and drop down its temperature and
pressure.
I.
The hot gas solenoid valve consists basically in
two parts: the valve body and the valve coil.
Located on the hot gas line, this valve is energized
through the micro processor of P.C. BOARD
during the defrost cycle as well as during the
water filling phase.
During the defrost cycle the hot gas valve coil is
activated so to attract the hot gas valve piston in
order to give way to the hot gas discharged from
compressor to flow directly into the evaporator
serpentine to defrost the formed ice cubes.
J.
The fan motor is controlled through the P.C.
BOARD and the TRIAC by the condenser tempe-
rature sensor. Normally it operates only during
the freezing cycle to draw cooling air through the
WATER INLET SOLENOID VALVE -
3/4 MALE FITTING
(Water cooled version)
HOT GAS SOLENOID VALVE
FAN MOTOR (Air cooled version)
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