Scotsman AF Series Service Manual page 27

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G. JUMPERS
The Flaker PC Board is equipped by three jumpers:
J1 · TEST: Used in the factory to energise all
the electrical components during the
Testing Mode.
Used to by-pass the 3' stand by time
(just jump the contacts with PC Board
under power).
J2 - SYEN
J3 - Pro. El. Ind.
· 60/70°C: Used to set up the Cut Out tempera-
ture of the condenser sensor:
• Jump OUT = 60°C
• Jump IN
J3 - SYEN
J2 - Pro. El. Ind.
· 3'/60': Used to set up the start up delai time:
• Jump IN
• Jump OUT = 60'
H. FLOAT RESERVOIR
The float reservoir consists of a plastic water pan
on which is fitted a float valve with its setting
screw. The float valve modulate the incoming
water flow to maintain a constant water level in
the reservoir, level that corresponds to the one in
the freezing cylinder to ensure proper ice
formation and fluidity.
On the inner side of the reservoir cover are fitted
the two water level sensors which detects the
presence or the shortage of water in the reservoir.
NOTE. It is very important to make sure of
the correct fitting of the cover on the reservoir
in order to enable the sensor to efficiently
control the water situation avoiding undue
shutoff interventions.
I. FREEZING CYLINDER (EVAPORATOR)
The freezing cylinder is made of a stainless steel
vertical tube on which exterior is wrapped around
the cooling coil with the evaporating chamber
and in its interior is located the auger which
rotates on its vertical axis and it is maintained
aligned by the top and bottom bearings. A water
seal system is located in the bottom part of the
freezer while at the top end is fitted the ice
breaker.
The water constantly flowing into the cylinder
bottom part, freezes into ice when in contact with
the cylinder inner walls. The ice is then lifted up
by the rotating auger and compacted and forced
out by the ice breaker.
J. ICE BREAKER
The ice breaker is fitted in the freezer upper part
it has two breaker teeth to break the ice and with
its slanted shape from the rear tooth to the front
one it compacts and forces the ice out in an
horizontal way. By undergoing this, the ice looses
its excess of water content so it drops into the bin
in hard dry bits of ice.
= 70°C
= 3'
In the ice breaker it is housed the top bearing
which is made of two rolls bearings positioned to
withstand the auger axial and radial loads. This
bearing is lubricated with a food grade - water
resistant grease.
NOTE. It is advisable to check the conditions
of both the lubricant grease and the top
bearing every six months.
K. DRIVE GEAR MOTOR
This motoreducer is made of a single phase
electric motor with permanent capacitor directly
fitted on a gear box.
The drive motor rotor is kept aligned on its vertical
axis by two ball bearings permanently lubricated.
The gear case contains a train of three spur gears
the first one of which is in fiber to limit the noise
level. All the three gears are encased in case
bearings and are covered by lubricant grease
(MOBILPLEX IP 44).
Two seal rings, one fitted on the rotor shaft and
the other on the output shaft keep the gear case
sealed.
Hovewer, the interior can be inspected and
serviced by unbolting the two halves of the
aluminium gear case housing.
The gear reducer output shaft is connected to the
freezer auger by a ratched coupling which is
made of two toothed halves that engages
themselves only if turned in the correct direction
namely, conterclockwise.
L. FAN MOTOR (Air cooled version)
The fan motor is controlled through the P.C.
BOARD and the TRIAC by the condenser tempe-
rature sensor. Normally it operates to draw cooling
air through the condenser fins.
In cold ambient situation, the fan motor can run at
intermittance as the condenser pressure must be
kept between two corresponding head pressure
values (8.5÷9.5 bars-120÷135 psig) - (17÷18 bar-
245÷260 psig on AF 30 only).
M. WATER REGULATING VALVE
(Water cooled version)
This valve controls the head pressure in the
refrigerant system by regulating the flow of water
going to the condenser.
As pressure increases, the water regulating val-
ve opens to increase the flow of cooling water.
N. COMPRESSOR
The hermetic compressor is the heart of the
refrigerant system 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.
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