Scotsman CMS1202R Service Manual page 24

CMS1202R
SERVICE DIAGNOSIS: Bin Ice Level Control
CONDITION
Ice Machine does not run, it has
power to it, the high pressure control
is closed, the on/off switch is set to
ON (the compressor will not operate
until the liquid line valve opens, but
the pump should be working if there
is no ice in the bin).
Machine runs, makes ice, switches
on and off, but ice level cannot be
controlled.
Machine runs, but will not shut off.
PARTIAL
VIEW OF
CIRCUIT
BOARD
12-1912-01
DETERMINE CAUSE
A. Listen for a ticking sound from
transducer.
B. Remove front panel(s), twist
transducer 1/4 turn and pull out. DO
NOT UNPLUG with power
connected. Examine the transducer,
the inside must be clean and dry.
C. Check power to bin level control
board.
D. Disconnect electrical power and
test ice machine circuit by attaching a
jumper wire between bin thermostat
posts on circuit board part no.
12-1912-01 (the circuit board with the
timer on it). Reconnect power.
E. Transducer or ice level board
assembly defective.
Ice level switch may be defective. On
boards with a light, check by moving
switch & watching light.
Board relay stuck closed. Check
relay.
PLUG - IN
RELAY
TIMER
BIN THERMOSTAT
September 1993
Page 24
PROBABLE CORRECTION
If no noise, go to C. If there is a
noise, check for a light on the board
(models built after 4/93). If there is a
light on, check relay contacts N.O.
and COM. The contacts should be
CLOSED. If closed, go to D. If not,
replace the board. If light is off, or
prior model, go to B.
If the inside of the transducer (above
screen) was wet, replace it. Set bin
level to FULL and aim at an object
about 1-3 feet away. Machine should
restart, if not go to D.
Should be 12 volts from transformer,
if not replace transformer. If there is
power go to D.
If machine does not start go back to
machine circuit. If machine starts,
disconnect electrical power, remove
jumper wire and reconnect electrical
power. Then go to E.
Replace transducer. Set bin level to
FULL and aim at an object about 1-3
feet away. Machine should restart. If
this does not repair unit, replace the
board.
Replace ice level switch
If COM and N.O. are closed when
power is off, replace board. If open,
go to B above.
Electrical Shock Hazard
Can Cause Personal Injury.
Disconnect Power Before
Servicing.
Bin Thermostat Posts at
Line Voltage.
POSTS MENTIONED IN
"D" ABOVE