Scotsman ACM 85 User manual

SERVICE MANUAL
ACM 85
AC 125
AC 175
AC 225
R 134 A / R 404 AVERSIONS
Electronic cubers
with storage
MS 1000.08 REV. 03/98

Table of contents page
Specifications ACM 85
Specifications AC 125
Specifications AC 175
Specifications AC 225
GENERAL INFORMATION AND INSTALLATION
Introduction
Unpacking and Inspection
Location and levelling
Electrical connections
Water supply and drain connections
Final check list
Installation practice
OPERATING INSTRUCTIONS
Start up
Operational checks
OPERATING PRINCIPLES (How it works)
Freezing cycle
Harvest cycle
Control sequence
Component description
ADJUSTMENT, REMOVAL AND REPLACEMENT PROCEDURES
Adjustment of the cube size
Replacement of evaporator temperature sensor
Replacement of condenser temperature sensor
Replacement of ambient temperature sensor
Replacement of ice level light control
Replacement of P.C. Board
Replacement of the water pump (ACM 85)
Replacement of the water pump (AC 125 & AC 175 )
Replacement of the water pump (AC 225)
Replacement of water inlet solenoid valve
Replacement of hot gas valve coil
Replacement of water drain solenoid valve
Replacement of fan motor
Replacement of plastic curtain (ACM 85 & AC 125-175)
Replacement of spray platform and chute (ACM 85 & AC 125-175)
Replacement of spray bar (AC 225)
Replacement of drier
Replacement of hot gas valve body
Replacement of evaporator platen
Replacement of air cooled condenser
Replacement of water cooled condenser
Replacement of water regulating valve (water cooled models)
Replacement of compressor
Wiring diagram (ACM 85)
Wiring diagram (AC 125-175 & AC 225)
Service diagnosis
MAINTENANCE AND CLEANING INSTRUCTIONS
General
Icemaker
Cleaning instructions of water system
Page 01
TABLE
OF CONTENTS
1
2
4
6
8
10
10
10
11
11
11
12
13
14
18
21
22
23
27
28
28
28
28
28
28
29
29
29
29
29
29
30
30
30
30
30
30
31
31
31
32
33
34
35
38
38
39

SPECIFICATIONS
ELECTRONIC CUBER MODEL ACM 85
Important operating requirements:
MIN MAX
Air temperature 10°C (50°F) 40°C (100°¯F)
Water temperature 5°C (40°F) 40°C (100°F)
Water pressure 1 bar (14 psi) 5 bar (70 psi)
Electr. voltage
variations from
voltage rating
specified on
nameplate -10% +10%
ice making capacity
NOTE. With the unit in “built-in” conditions, the ice production is gradually reduced in respect to the
levels shown in the graf, up to a maximum of 10% at room temperatures higher than 32 ° C.
The daily ice-making capacity is directly related to the condenser air inlet temperature, water
temperature and age of the machine.
To keep your SCOTSMAN CUBER at peak performance levels, periodic maintenance checks
must be carried out as indicated on page 38 of this manual.
Page 02
40
38
36
34
32
30
28
26
Kg.
32 °C
AIR COOLED MODELS
WATER TEMPERATURE
AMBIENT TEMPERATURE
ICE PRODUCED PER 24 HRS.
°C
10
21
32
38
40
38
36
34
32
30
28
26
Kg.
°C
WATER COOLED MODELS
WATER TEMPERATURE
AMBIENT TEMPERATURE
ICE PRODUCED PER 24 HRS.
°C
10
21
32
38
27 21 15 10 32 27 21 15 10

Basic electr. Amps. Start Amps Watts No of Wires Amp. Fuse
Page 03
SPECIFICATIONS (CONT'D)
Electr. power cons.
Kwh per 24 Hrs
230/50/1 3.2 17 500 10 3 x 1 m/m 10
2
Cubes per harvest: 24 medium
* At 15°C (60°F) water temperature
ACM 85 - CUBER MACHINE SPECIFICATION
Model Cond. Finish Comp. HP Ice bin cap. Water requirem
Kgs. LTx24 HR
ACM 85 AS Air S/Steel 140*
3/8 14
ACM 85 WS Water S/Steel 380*
FRONT VIEW
HEIGHT (without legs) 790 mm.
HEIGHT (with legs) 930 mm.
WIDTH 457 mm.
DEPTH 523 mm.
WEIGHT 44 Kgs.

SPECIFICATIONS
ELECTRONIC CUBER MODEL AC 125
Important operating requirements:
MIN MAX
Air temperature 10°C (50°F) 40°C (100°¯F)
Water temperature 5°C (40°F) 40°C (100°F)
Water pressure 1 bar (14 psi) 5 bar (70 psi)
Electr. voltage
variations from
voltage rating
specified on
nameplate -10% +10%
ice making capacity
NOTE. With the unit in “built-in” conditions, the ice production is gradually reduced in respect to the
levels shown in the graf, up to a maximum of 10% at room temperatures higher than 32 ° C.
The daily ice-making capacity is directly related to the condenser air inlet temperature, water
temperature and age of the machine.
To keep your SCOTSMAN CUBER at peak performance levels, periodic maintenance checks
must be carried out as indicated on page 38 of this manual.
Production charts shown indicate the production of ACM models; ice production of ACL and
ACS models is 10% lower.
Page 04
75
70
65
60
55
50
45
Kg.
32 °C27 21 15 10
AIR COOLED MODELS
WATER TEMPERATURE
AMBIENT TEMPERATURE
ICE PRODUCED PER 24 HRS.
°C
10
21
32
38
75
70
65
60
55
50
45
Kg.
°C
WATER COOLED MODELS
WATER TEMPERATURE
AMBIENT TEMPERATURE
ICE PRODUCED PER 24 HRS.
°C
32
38
10 21
32 27 21 15 10

Basic electr. Amps. Start Amps Watts No of Wires Amp. Fuse
Page 05
SPECIFICATIONS (CONT'D)
Electr. power cons.
Kwh per 24 Hrs
230/50/1 3.8 20 670 13 3 x 1 m/m 10
Cubes per harvest: 36 large / 48 medium / 84 small
* At 15°C (60°F) water temperature
Ice bin cap. Water requirem
Kgs. LTx24 HR
AC 125 AS Air S/Steel 160*
1/2 28
AC 125 WS Water S/Steel 680*
AC 125 - CUBER MACHINE SPECIFICATIONS
Model Cond. Finish Comp. HP
FRONT VIEW
HEIGHT (without legs) 900 mm.
HEIGHT (with legs) 1020 mm.
WIDTH 675 mm.
DEPTH 520 mm.
WEIGHT 75 Kgs.
2

SPECIFICATIONS
ELECTRONIC CUBER MODEL AC 175
Important operating requirements:
MIN MAX
Air temperature 10°C (50°F) 40°C (100°¯F)
Water temperature 5°C (40°F) 40°C (100°F)
Water pressure 1 bar (14 psi) 5 bar (70 psi)
Electr. voltage
variations from
voltage rating
specified on
nameplate -10% +10%
ice making capacity
NOTE. With the unit in “built-in” conditions, the ice production is gradually reduced in respect to the
levels shown in the graf, up to a maximum of 10% at room temperatures higher than 32 ° C.
The daily ice-making capacity is directly related to the condenser air inlet temperature, water
temperature and age of the machine.
To keep your SCOTSMAN CUBER at peak performance levels, periodic maintenance checks
must be carried out as indicated on page 38 of this manual.
Production charts shown indicate the production of ACM models; ice production of ACL and
ACS models is 10% lower.
Page 06
87,5
Kg.
32 10 °C
AIR COOLED MODELS
WATER TEMPERATURE
AMBIENT TEMPERATURE
ICE PRODUCED PER 24 HRS.
°C
10
21
32
38
WATER COOLED MODELS
10
21
27 21 15
85
82,5
80
77,5
75
72,5
70
67,5
65
62,5
60
57,5
87,5
Kg.
32 10 °C
WATER TEMPERATURE
AMBIENT TEMPERATURE
ICE PRODUCED PER 24 HRS.
°C
10
21
10
21
32
38
27 21 15
85
82,5
80
77,5
75
72,5
70
67,5
65
90
92,5
95

Basic electr. Amps. Start Amps Watts No of Wires Amp. Fuse
SPECIFICATIONS (CONT'D)
Electr. power cons.
Kwh per 24 Hrs
230/50/1 5.3 29 850 18 3 x 1 m/m 16
Cubes per harvest: 36 large / 48 medium
* At 15°C (60°F) water temperature
Ice bin cap. Water requirem
Kgs. LTx24 HR
AC 175 AS Air S/Steel 0160*
3/4 28
AC 175 WS Water S/Steel 1000*
AC 175 - CUBER MACHINE SPECIFICATIONS
Model Cond. Finish Comp. HP
FRONT VIEW
HEIGHT (without legs) 900 mm.
HEIGHT (with legs) 1020 mm.
WIDTH 675 mm.
DEPTH 520 mm.
WEIGHT 75 Kgs.
Page 07
2

SPECIFICATIONS
ELECTRONIC CUBER MODEL AC 225
Important operating requirements:
MIN MAX
Air temperature 10°C (50°F) 40°C (100°¯F)
Water temperature 5°C (40°F) 40°C (100°F)
Water pressure 1 bar (14 psi) 5 bar (70 psi)
Electr. voltage
variations from
voltage rating
specified on
nameplate -10% +10%
ice making capacity
NOTE. With the unit in “built-in” conditions, the ice production is gradually reduced in respect to the
levels shown in the graf, up to a maximum of 10% at room temperatures higher than 32 ° C.
The daily ice-making capacity is directly related to the condenser air inlet temperature, water
temperature and age of the machine.
To keep your SCOTSMAN CUBER at peak performance levels, periodic maintenance checks
must be carried out as indicated on page 38 of this manual.
Production charts shown indicate the production of ACM models; ice production of ACL and
ACS models is 10% lower.
Page 08
150
145
140
135
130
125
120
115
110
105
100
95
90
85
Kg.
32 °C
AIR COOLED MODELS
WATER TEMPERATURE
AMBIENT TEMPERATURE
ICE PRODUCED PER 24 HRS.
°C
10
21
32
38
WATER COOLED MODELS
27 21 15 10
160
155
150
145
140
135
130
125
120
115
110
105
100
95
Kg.
32 °C
WATER TEMPERATURE
AMBIENT TEMPERATURE
ICE PRODUCED PER 24 HRS.
°C
10
21
32
38
27 21 15 10

Basic electr. Amps. Start Amps Watts No of Wires Amp. Fuse
Page 09
SPECIFICATIONS (CONT'D)
Electr. power cons.
Kwh per 24 Hrs
230/50/1 5.3 29 1100 22 3 x 1.5 m/m 16
Cubes per harvest: 72 large / 102 medium / 198 small.
* At 15°C (60°F) water temperature
2
FRONT VIEW
HEIGHT (without legs) 1006 mm.
HEIGHT (with legs) 1126 mm.
WIDTH 1078 mm.
DEPTH 660 mm.
WEIGHT 115 Kgs.
AC 225 - CUBER MACHINE SPECIFICATIONS
Model Cond. Finish Comp. HP Ice bin cap. Water requirem
Kgs. LTx24 HR
AC 225 AS Air S/Steel 0250*
170
AC 225 WS Water S/Steel 1500*

A. INTRODUCTION
This manual provides the specifications and the
step-by-stepproceduresfortheinstallation,start-
up and operation, maintenance and cleaning for
the SCOTSMAN ACM 85, AC 125, AC 175 and
AC 225 icemakers.
The Electronic Cubers are quality designed,
engineered and manufactured.
Their ice making systems are thoroughly tested
providing the utmost in flexibility to fit the needs
of a particular user.
NOTE.Toretainthesafetyandperformance
built into this icemaker, it is important that
installation and maintenance be conducted
in the manner outlined in this manual.
B. UNPACKING AND INSPECTION
1. CallyourauthorizedSCOTSMANDistributor
or Dealer for proper installation.
2. Visually inspect the exterior of the packing
and skid. Any severe damage noted should be
reportedtothedeliveringcarrierandaconcealed
damageclaimformfilledinsubjettoinspectionof
the contents with the carrier’s representative
present.
3. a)Cutandremovetheplasticstripsecuring
the carton box to the skid.
b) Remove the packing nails securing the
carton box to the skid.
c)Cutopenthetopofthecartonandremove
the polystyre protection sheet.
d)Pulloutthepolystyrepostfromthecorners
and then remove the carton.
4. Remove the front and (if any) the rear
panels of the unit and inspect for any concealed
damage. Notify carrier of your claim for the
concealed damage as steted in step 2 above.
5. Remove all internal support packing and
masking tape. (Leg package is located in the
storage bin compartment).
6. Check that refrigerant lines do not rub
against or tuch other lines or surfaces, and that
the fan blade moves freely.
7. Check that the compressor fits snugly onto
all its mounting pads.
8. Use clean damp cloth to wipe the surfaces
inside the storage bin and the outside of the
cabinet.
GENERAL INFORMATION AND INSTALLATION
Page 010
9. See data plate on the rear side of the unit
and check that local main voltage corresponds
with the voltage specified on it.
CAUTION. Incorrect voltage supplied to
the icemaker will void your parts
replacement program.
10. Remove the manufacturer’s registration
card from the inside of the User Manual and fill-
in all parts including: Model and Serial Number
taken from the data plate.
Forward the completed self-addressed
registration card to the SCOTSMAN Europe
Frimont factory.
11. If necessary fit the four legs into their seats
on the machine base and adjust them to the
desired level.
C. LOCATION AND LEVELING
WARNING.ThisIceCuberis designedfor
indoorinstallationonly.Extendedperiods
of operation at temperature exceeding
the following limitations will constitute
misuseunderthetermsoftheSCOTSMAN
Manufacturer’sLimitedWarrantyresulting
in LOSS or warranty coverage.
1. Position the unit in the selected permanent
location.
Criteria for selection of location include:
a)Minimumroomtemperature10°C(50°F)
and maximum room temperature 40°C (100°F).
b) Water inlet temperatures: minimum 5°C
(40°F) and maximum 40°C (100°F).
c) Well ventilated location for air cooled
models. Clean the air cooled condenser at
frequent intervals.
d)Serviceaccess:adequatespacemustbe
leftforallserviceconnectionsthroughtherearof
the ice maker. A minimum clearance of 15 cm
(6")mustbeleftatthesidesoftheunitforrouting
cooling air drawn into and exhausted out of the
compartment to maintain proper condensing
operation of air cooled models.
2. Level the unit in both the left to right and
front to rear directions.

D. ELECTRICAL CONNECTIONS
See data plate for current requirements to
determine wire size to be used for electrical
connections.AllSCOTSMANicemakers require
a solid earth wire.
All SCOTSMAN ice machines are supplied from
thefactorycompletelypre-wiredandrequireonly
electricalpowerconnectionstowirecordprovided
at the rear of the unit.
Make sure that the ice machine is connected to
its own circuit and individually fused (see data
plate for fuse size).
Themaximumallowablevoltagevariationshould
not exceed -10% and + 10% of the data plate
rating. Low voltage can cause faulty functioning
and may be responsible for serious damage to
the overload switch and motor windings.
NOTE. All external wiring should conform to
national, state and local standards and
regulations.
Check voltage on the line and the ice maker’s
data plate before connecting the unit.
E. WATER SUPPLY AND DRAIN
CONNECTIONS
GENERAL
Whenchoosingthewatersupplyfortheicecuber
consideration should be given to:
a) Length of run
b) Water clarity and purity
c) Adequate water supply pressure
Sincewateristhemostimportantsingleingredient
in producting ice you cannot emphasize too
much the three items listed above.
Low water pressure, below 1 bar may cause
malfunction of the ice maker unit.
Water containing excessive minerals will tend to
produce cloudy coloured ice cubes, plus scale
build-up on parts of the water system.
WATER SUPPLY
Connect the 3/4" male fitting of the solenoid
waterinletvalve, usingtheflexible tubesupplied
tothecoldwatersupplylinewithregularplumbing
fitting and a shut-off valve installed in an
accessible position between the water supply
line and the unit.
If water contains a high level of impurities, it is
advisable to consider the installation of an
appropriate water filter or conditioner.
Page 11
WATERSUPPLY-WATERCOOLEDMODELS
The water cooled versions of SCOTSMAN Ice
Makersrequiretwoseparateinletwatersupplies,
one for water sprayed for making the ice cubes
and the other for the water cooled condenser.
Connect the 3/4" male fitting of the water inlet,
using the flexible tube supplied to the cold water
supply line with regular plumbing fitting and a
shut-off valve installed in an accessible position
between the water supply line and the unit.
WATER DRAIN
The recommended drain tube is a plastic or
flexible tube with 18 mm (3/4") I.D. which runs to
an open trapped and vented drain. When the
drain is a long run, allow 3 cm pitch per meter
(1/4" pitch per foot)
Aventattheunitdrainconnectionisalsorequired
for proper sump drainage.
WATER DRAIN - WATER COOLED MODELS
Connect the 3/4" male fitting of the condenser
water drain, utilizing a second flexible tubing to
the open trapped and vented drain.
NOTE.Thewatersupplyandthewaterdrain
must be installed to conform with the local
code. In some case a licensed plumber and/
or a plumbing permit is required.
F. FINAL CHECK LIST
1. Is the unit level? (IMPORTANT)
2. Have all the electrical and plumbing
connectionsbeenmade, andisthe watersupply
shut-off valve open?
3. Has the voltage been tested and checked
against the data plate rating?
4. Have the bin liner and cabinet been wiped
clean?
5. Havetheboltsholdingthecompressordown
been checked to ensure that the compressor is
snugly fitted onto the mounting pads?
6. Has the owner/user been given the User
Manualandbeeninstructedontheimportanceof
periodic maintenance checks?
7. Has the Manufacturer’s registration card
been filled in properly? Check for correct model
and serial number against the serial plate and
mail the registration card to the factory.

8. Check all refrigerant lines and conduit
lines to guard against vibrations and possible
failure.
9. Is the unit in a room where ambient
temperatures are within a minimum of 10°C
(50¯F) even in winter months?
10. Is there at least a 15 cm (6") clearance
Page 12
around the unit for proper air circulation?
11. Has the water supply pressure been
checked to ensure a water pressure of at least 1
bar (14 psi).
12. Hastheownerbeengiventhenameandthe
phone number of the authorized SCOTSMAN
Service Agency serving him?
WARNING.Thisicemakerisnotdesignedforoutdoorinstallationandwillnotfunction
in ambient temperatures below 10°C (50°F) or above 40°C (100°F).
This icemaker will malfunction with water temperatures below 5°C (40°F) or above
40°C (100°F).
1. Hand shut-off valve
2. Water filter
3. Water supply line (flexible hose)
4. 3/4" male fitting
5. Vented drain
6. Open trapped vented drain
7. Drain fitting
8. Main switch
9. Power line
G. INSTALLATION PRACTICE

START UP
Afterhavingcorrectlyinstalledtheicemakerand
completed the plumbing and electrical
connections, perform the following “Start-up”
procedure.
A. Give power to the unit to start it up by
switching “ON” the power line main disconnect
switch.
NOTE. Every time the unit returns under
power, after having been switched off, the
water inlet valve, the hot gas valve and the
water drain valve get energized for a period
of 5 minutes, thus to admit new water to the
machine sump reservoir to fill it up and,
eventually,towash-offanydirtthatcanhave
deposited in it during the unit off period
(Fig.1).
B. During the water filling operation, check to
seethattheincomingwaterdribbles,throughthe
evaporator platen dribbler holes, down into the
OPERATING INSTRUCTIONS
Page 13
sump reservoir to fill it up and also that the
incoming surplus of water flows out through the
overflow pipe into the drain line.
During the water filling phase the components
energized are:
THE WATER INLET SOLENOID VALVE
THE HOT GAS SOLENOID VALVE
THE WATER DRAIN SOLENOID VALVE
NOTE.Ifinthe5 minuteslenghtofthewater
filling phase the machine sump reservoir
does not get filled with water up to the rim of
the overflow pipe, it is advisable to check:
1.Thewaterpressureofthewatersupplyline
thatmustbeatleast1bar(14psig)Minimum
(Max 5 bar-70 psig).
2.The filtering device installed in the water
line that may reduce the water pressure
below the Minimum value of 1 bar (14 psig).
3. Any clogging situation in the water circuit
like the inlet water strainer and/or the flow
control.
16
15
14
13
2
1
7
8
9
10
3
4
5
6
11
12
Rx Tx
WATER IN VALVE
HOT GAS VALVE
CONTACTOR COIL
FAN MOTOR
WATER PUMP
- EVAPORATOR
- AMBIENT
- CONDENSER
TEMPERATURE SENSORSBINCOMPRESSOR
TRANSF.
DATA
PROCESSOR
ELECTR.
TIMER
DIP
SWITCH
ELECTRONIC CARD
L
N
RELAYS
RELAY
TRIAC
WATER DRAIN VALVE
FIG. 1

C. At completion of the water filling phase
(5minutes)theunitpassesautomaticallyintothe
freezing cycle with the start up of:
COMPRESSOR
WATER PUMP
FAN MOTOR (in air cooled version) controlled
by the condensing temperature sensor located
within the condenser fins (Fig.2).
OPERATIONAL CHECKS
D. Install, if required, the refrigerant service
gauges on both the high side and low side
Scraeder valves to check the compressor head
and suction pressures.
NOTE.On aircooledmodels,thecondenser
temperature sensor, which is located within
the condenser fins, keep the head
(condensing) pressure between 8.5 and 9.5
bar (110 ÷ 130 psig) on models ACM 85,
AC125 and AC175 andbetween15 and17
bar on model AC 225.
Page 14
Incaseofcondensercloggingsuchtoprevent
the proper flow of the cooling air or, in case
the fan motor is out of operation or shortage
of water in the water cooled condenser, the
condenser temperature rises and when it
reaches70 ° C(160 ° F)-foraircooledversion
- or 62 ° C (145 ° F) - for water cooled version -
the condenser temperature sensor shuts-off
theicemakerwiththe consequentlight-upof
the RED WARNING LIGHT (Fig.3).
Afterhavingdiagnosedthereasonoftherise
of temperature and removed its cause, it is
necessary to turn the head of the selector -
alwaysusinganappropriatescewdriver-first
on the RE-SET position then return it on
previous OPERATION position or unplug
(waitfewseconds)andpluginagaintheunit,
thustoputthemachineinconditiontoinitiate
a new freezing cycle.
Themachinerestartswiththeusual5minutes
waterfillingphaseinordertoprovideenough
water into the sump tank.
16
15
14
13
2
1
7
8
9
10
3
4
5
6
11
12
Rx Tx
WATER IN VALVE
HOT GAS VALVE
CONTACTOR COIL
FAN MOTOR
WATER PUMP
- EVAPORATOR
- AMBIENT
- CONDENSER
TEMPERATURE SENSORSBINCOMPRESSOR
TRANSF.
DATA
PROCESSOR
ELECTR.
TIMER
DIP
SWITCH
ELECTRONIC CARD
L
N
RELAYS
RELAY
TRIAC
WATER DRAIN VALVE
FIG. 2

Page 15
E. Checktoseethrough theicedischarge
opening that the spray system is correctly
seated and that the water jets uniformely
reach the interior of the inverted mold cups;
also make sure that the plastic curtain
(ACM 85 & AC 125-175) is hanging freely
and there is not excessive water spilling
through it.
16
15
14
13
2
1
7
8
9
10
3
4
5
6
11
12
Rx Tx
WATER IN VALVE
HOT GAS VALVE
CONTACTOR COIL
FAN MOTOR
WATER PUMP
- EVAPORATOR
- AMBIENT
- CONDENSER
TEMPERATURE SENSORSBINCOMPRESSOR
TRANSF.
DATA
PROCESSOR
ELECTR.
TIMER
DIP
SWITCH
ELECTRONIC CARD
L
N
RELAYS
RELAY
TRIAC
WATER DRAIN VALVE
16
15
14
13
2
1
7
8
9
10
3
4
5
6
11
12
Rx Tx
WATER IN VALVE
HOT GAS VALVE
CONTACTOR COIL
FAN MOTOR
WATER PUMP
- EVAPORATOR
- AMBIENT
- CONDENSER
TEMPERATURE SENSORSBINCOMPRESSOR
TRANSF.
DATA
PROCESSOR
ELECTR.
TIMER
DIP
SWITCH
ELECTRONIC CARD
L
N
RELAYS
RELAY
TRIAC
WATER DRAIN VALVE
FIG. 3
FIG. 4

F. Theicemakingprocesstakesplacethereby,
with the water sprayed into the molds that gets
graduallyrefrigeratedbythe heat exchangewith
the refrigerant flowing into the evaporator
serpentine. During the freezing process, when
the evaporator temperature falls below an
established value, the evaporator temperature
sensorsuppliesalowvoltagepowersignaltothe
electronic control device (P.C.BOARD) in order
to activate an electronic timer. This one takes
over the control of the freezing cycle up to the
complete formation of the ice cubes (Fig.4).
NOTE.Thelenghtoftheentirefreezingcycle
is governed by the evaporator temperature
sensorwhich has its probe placed in contact
with the evaporator serpentine (Non
adjustable)incombinationwiththeelectronic
timer (Adjustable) incorporated in the
P.C.BOARD.Thetimeradjustmentisfactory
set in consideration of the ice maker type,
cooling version and ice cube size (Small,
Medium, Large). It is possible, however, to
modifythetimedlenghtofthefreezingcycle,
by changing the DIP SWITCH keys setting.
In Table B of PRINCIPLE OF OPERATION
areshownthevarioustimeextensionsofthe
freezingcycle second phase, in relation with
the different DIP SWITCH keys setting.
G. Afterabout17÷20minutesfromthebegin-
ning of the freezing cycle, in an hypothetic
ambienttemperatureof21°C,thedefrostcycle
takes place with the hot gas, the water inlet
and the water drain valves simoultaneously
activated (Fig. 5).
Theelectricalcomponentsinoperationonmodels
are:
COMPRESSOR
WATER INLET VALVE
HOT GAS VALVE
WATER DRAIN VALVE
and the
WATER PUMP
on the first 15 seconds on model ACM 85 &
AC 125-175 and on the first 30 seconds on
model AC 225.
NOTE. The lenght of the defrost cycle is
determinated by the DIP SWITCH keys
setting in conjunction with the ambient tem-
perature sensor located just in front of the
condenser. The lenght of defrost cycle can
be adjusted by changing the combination
settingof keys 5,6 and 7 ofDIP SWITCH as
illustrated on Table C of PRINCIPLE OF
OPERATION.
As shown, per each individual keys
combination,itispossibletohaveadifferent
lenght of the defrost cycle in relation to the
different ambient temperature situations;
shorter when the ambient temperature is
highandlongerincolderambientstopartially
compensatethelenghtofthefreezingcycle,
whichislongerinhighambienttemperatures
and shorter in low ones.
Page 16
16
15
14
13
2
1
7
8
9
10
3
4
5
6
11
12
Rx Tx
WATER IN VALVE
HOT GAS VALVE
CONTACTOR COIL
FAN MOTOR
WATER PUMP
- EVAPORATOR
- AMBIENT
- CONDENSER
TEMPERATURE SENSORSBINCOMPRESSOR
TRANSF.
DATA
PROCESSOR
ELECTR.
TIMER
DIP
SWITCH
ELECTRONIC CARD
L
N
RELAYS
RELAY
TRIAC
WATER DRAIN VALVE
FIG. 5

beam;theREDLIGHT,locatedinthefrontofthe
P.C.BOARD, will glow immediately.
After approximately 6 seconds the ice maker
resumeitsoperationwith theimmediateglowing
oftheFOURTHYELLOWLIGHTindicatingUNIT
IN OPERATION and the extinguishing of the
“BIN FULL” YELLOW LIGHT.
NOTE. The ICE LEVEL CONTROL
(INFRAREDSYSTEM)isindependentofthe
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,alsoitisrecommendedtokeepthe
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
PROCEDURES.
K. Remove,iffitted,therefrigerantservice
gauges and re-fit the unit service panels
previously removed.
L. Instruct the owner/user on the general
operation of the ice machine and about the
cleaning and care it requires.
Page 17
H. Check, during the defrost cycle, that the
incoming water flows correctly into the sump
reservoir in order to refill it and that the surplus
overflows through the overflow drain tube.
I. Checkthetextureoficecubesjustreleased.
They have to be in the right shape with a small
depression of about 5-6 mm in their crown.
Ifnot,waitforthecompletionofthesecondcycle
before performing any adjustment.
Ifrequired,the lenghtofthe timedfreezingcycle
can be modified by changing the DIP SWITCH
keys setting as illustrated in OPERATING
PRINCIPLE.
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.
J. To be sure of the correct operation of ice
levelcontrol device,place onehand betweenits
sensing “eyes” to interrupt the light beam.
The RED LIGHT located in the front of the
P.C.BOARD goes immediately OFF, and after
60seconds,theunitstopswiththesimultaneous
glowing of the 2nd YELLOW LIGHT to monitor
the BIN FULL situation (Fig.6).
Take the hand out from the ice level control
sensors to allow the resumption of the light
16
15
14
13
2
1
7
8
9
10
3
4
5
6
11
12
Rx Tx
WATER IN VALVE
HOT GAS VALVE
CONTACTOR COIL
FAN MOTOR
WATER PUMP
- EVAPORATOR
- AMBIENT
- CONDENSER
TEMPERATURE SENSORSBINCOMPRESSOR
TRANSF.
DATA
PROCESSOR
ELECTR.
TIMER
DIP
SWITCH
ELECTRONIC CARD
L
N
RELAYS
RELAY
TRIAC
WATER DRAIN VALVE
FIG. 6

The timer, which is built-in the P.C. BOARD,
takes over from the evaporator temperature
sensor, the control of the freezing cycle up to its
completion.
NOTE.Thechangeoftheelectricpotentialof
the evaporator sensor with the consequent
activationofthetimer(Timemode)issignalled
bytheglowing-up ofthe REDLED locatedin
the front of the P.C. BOARD.
ATTENTION. In case, after 15 minutes
from the beginning of the freezing cycle,
thetemperatureof the evaporator sensor
probeishigherthen0°C(32°F)(shortage
of refrigerant, inoperative hot gas valve,
etc.) the P.C. BOARD switch OFF
immediately the unit with the
simultaneous blinking of the WARNING
RED LED.
The length of this second portion of the freezing
cycleis pre-fixedand relatedto thesetting ofthe
first four DIP SWITCH keys.
The DIP SWITCH keys setting is made in
consideration of the type of condenser used.
In Table B are indicated the various lengths of
thesecondportionoffreezingcycle(Timemode)
inrelationtothedifferentcombinationsoftheDIP
SWITCH KEYS.
In Table A herebelow are illustrated the DIP
SWITCHkeyscombinationsforthethreedifferent
models and versions as they are set in the
factory.
The electrical components in operation during
the freezing cycle are:
COMPRESSOR
FAN MOTOR (in air cooled version)
WATER PUMP
CONTACTOR COIL
and during the second phase of freezing cycle
(Time mode) they are joined by the
ELECTRONIC TIMER
PRINCIPLE OF OPERATION
How it works
In the SCOTSMAN cube ice makers the water
used to make the ice is kept constantly in
circulationbyanelectricwaterpumpwhichprimes
it to the spray system nozzles from where it is
diverted into the inverted mold cups of the
evaporator.Asmallquantityofthesprayedwater
freezesintoice; therestof itcascadesby gravity
into the sump assembly below for recirculation.
FREEZING CYCLE
The hot gas refrigerant discharged out from the
compressorreachesthecondenserwhere,being
cooleddown,condensesintoliquid.Flowinginto
the liquid line it passes through the drier filter,
thenitgoesallthewaythroughthecapillarytube
where, due to the heat exchanging action, it
loosessomeofitsheatcontentsothatitspressure
and temperature are lowered as well.
Next the refrigerant enters into the evaporator
serpentine (which has a larger I.D. then the
capillary) and starts to boil off; this reaction is
emphasized by the heat transferred by the
sprayed water.
The refrigerant then increases in volume and
changes entirely into vapor.
The vapor refrigerant then passes through the
suction accumulator (used to prevent that any
small amount of liquid refrigerant may reach the
compressor)andthroughthesuctionline.Inboth
theaccumulatorandthesuctionlineitexchanges
heatwiththe refrigerantflowing into thecapillary
tube (warmer), before to be sucked in the
compressor and to be recirculated as hot
compressed refrigerant gas.
Thefreezingcycleiscontrolledbytheevaporator
temperaturesensor(whichhasitsprobeincontact
with the evaporator serpentine) that determines
the length of its first portion of the cycle.
When the temperature of the evaporator
serpentinedropstoapre-setvalue,theevaporator
sensor probe changes its electrical resistance
allowingalowvoltagecurrent(15volts)toflowto
the P.C. BOARD which in turn activates an
electronic timer.
TAB. A
DIP SWITCH
1234
ACM 85 A
ACM 85 W
ACM 125 A
ACM 125 W
ACM 175 A & W
ACS 225 A & W
ACM 225 A & W
ACL 225 A & W
5678910
FREEZING CYCLE DEFROST CYCLE DIAGN. W.PUMP KWD
DIP SWITCH FACTORY SETTING COMBINATIONS PER MODEL AND VERSION
ON
ON
ON
OFF
OFF
OFF
ON
OFF
ON
ON
ON
ON
OFF
OFF
ON
OFF
OFF
OFF
OFF
OFF
OFF
ON
OFF
OFF
ON
ON
ON
ON
ON
ON
ON
ON
ON
OFF
ON
OFF
ON
OFF
OFF
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
OFF
ON
OFF
ON
OFF
ON
ON
ON
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
ON
ON
ON
ON
ON
ON
ON
ON
OFF
OFF
OFF
OFF
OFF
ON
ON
ON
Page 18

Page 19
FIG. A
FIG. C
FIG. B
FIG. C FIG. D
FIG. A