Scotsman AC-EC 57 Service Manual page 26

Page 26
FIG. 5
- EVAPORATOR
- CONDENSER
Rx Tx
L
N
If the ice cubes are shallow and cloudy, it is
possible that the ice maker runs short of water
during the freezing cycle second phase or, the
quality of the supplied water requires the use of
an appropriate water filter or conditioner. Only EC
version as soon as the water into the Sealed Water
Reservoir reaches the maximum level, the two metal
pins close the electrical contact through the water,
transmitting a low voltage current to the PC Board.
The PC Board activates the Water Drain Pump
for 8 seconds pumping out most of the water
contained into the Sealed Water Reservoir.
J. Upon the model, these icemakers range
shall operate either by IR control device which
operates by sensing eyes or Thermal sensor.
Thermal sensor can detecting both the low tem-
perature of the ice also the mass of the ice near
its sensing bulb.
For testing devices:
• Storage bin thermal sensor; place some ice
cubes in contact with the bulb, icemaker turn
OFF at the end of harvest cycle. Remove ice from the
bulb, ice maker restart from new freezing cycle.
16
DIP
SWITCH
ELECTR.
15
TIMER
13
1
2 TRANSF.
7
8
9
10
RELAYS
3
4
5
TRIAC
6
RELAY
11
12
• Optical level sensor (IR); place some ice
cubes between IR optical sensing eyes. The
Bin Full YELLOW LED starts blinking (Fig. 6),
and when defrost cycle is over, the unit stops
with the simultaneous glowing of the same LED
to monitor the BIN FULL situation (Fig. 6a).
• Whenever necessary, pcb can be "calibrated"
to assure the best comunication between the
same and ice level device just by turn the Main
switch OFF an ON again.
Take the hand out from the ice level control
sensors to allow the resumption of the light beam.
After approximately 6 seconds the ice maker
resume its operation with the immediate glowing
of the FIRST YELLOW LED indicating UNIT IN
OPERATION and the extinguishing of the "BIN
FULL" YELLOW LED.
NOTE. The ICE LEVEL CONTROL
(INFRARED SYSTEM) is independent of
the temperature however, the reliability of its
detection can be affected by external light
radiations or by any sort of dirt and scale
sediment which may deposit directly on the
light source and on the receiver.To prevent
any possible ice maker malfunction, due to
negative affection of the light detector, it is
advisable to locate the unit where it is not
reached by any direct light beam or light
radiation, also it is recommended to keep the
bin door constantly closed and to follow the
instructions for the periodical cleaning of
the light sensor elements as detailed in the
MAINTENANCE AND CLEANING PRO-
CEDURES.
This ice maker is equipped by an I/R self-
calibration PC Board every time ice maker is
turned OFF and ON by the main switch.
Page 26
WATER DRAIN VALVE
WATER IN VALVE
HOT GAS VALVE
COMPRESSOR
FAN MOTOR
WATER PUMP
ELECTRONIC CARD