Scotsman CME456R Service Manual

Introduction

CME456R

This product manual contains the information
needed for the setup, installation, initial start up,
sanitation and maintenance of this ice machine.
Keep it for future reference.

Be certain that the information applies to the model
in question. If no model is listed, the information
applies to all models.

Table of Contents

Specifications .............. Page 2

Condenser and Ice Machine Layouts . . Page 3

Pre-Installation .............. Page 4

Location & Assembly ........... Page 5

Bin Control: Optional Installation ..... Page 6

For The Installer: Remote Condenser . . Page 7

Remote Condenser Location ...... Page 8

Coupling Instructions ........... Page 9

This manual is organized in the same way as the
expected use of the machine, it begins with
specifications, goes thru unpacking and setup,
shows where everything is; continues with initial
start up, then describes how it works. After that is
the sanitation section, followed by service
diagnosis and repair.

Technicians Only: Harvest Cycle Sequence & Other

Notes .................. Page 22

Sanitation and Cleaning ........ Page 23

Additional Maintenance ......... Page 24

Additional Maintenance: Inlet Water Valve Screen

......................Page 25

Additional Maintenance: Ice Sensors, Condenser

......................Page 26

Service Diagnosis: Diagnostic Light Analysis .

......................Page 27

Fan Relay Kit .............. Page 10

Electrical ................ Page 11

Plumbing ................ Page 12

After Utility Connections ........ Page 13

Component Location and Function . . . Page 14

AutoIQ Controller ............ Page 15

Initial Start Up .............. Page 16

Adjustments .............. Page 17

How To Operate The AutoIQ Controller Page 18

How The Electronic Cuber Works . . . Page 19

How The Electronic Cuber Works . . . Page 20

Technicians Only: Freeze Cycle Sequence . . .

......................Page 21

Service Diagnosis ........... Page 28

Service Diagnosis: Components .... Page 29

Service Diagnosis ........... Page 30

Operational Characteristics: CME456R Page 31

Removal and Replacement ....... Page 32

Removal and Replacement: AutoIQ Controller .

......................Page 33

Removal and Replacement: Water Level Sensor

......................Page 34

Refrigerant ............... Page 35

Before Calling for Service ....... Page 36

Parts Lists and Wiring Diagrams are in the section at the center of this manual.

December 2000

Page 1

CME456R

Specifications

This ice machines is designed to be installed
indoors, in a controlled environment. It can operate
satisfactorily under a wide variety of conditions.
However, Do NOT operate the machine in
temperatures it has not been designed for. Do
NOT operate the machine above or below the
voltage limits for the particular model. Do NOT
operate the machine with too little or too much
water pressure.

Ice Machine Operational Limits

Minimum Maximum

Air Temperature 50oF. 100oF.

Water Temperature 40oF. 100oF.

Water Pressure 20 psi 80 psi

Voltage (60 Hz) 104 126

Remote Condenser Operational Limits

Minimum Maximum

Air Temperature -20oF. 120oF.

Voltage (60 Hz) 104 126

Scotsman reserves the right to make design
changes and/or improvements at any time.
Specifications and designs are subject to change
without notice.

Scotsman assumes no liability or responsibility of
any kind for products manufactured by Scotsman
that have been altered in any way, including the
use of any parts and/or other components not
specifically approved by Scotsman.

Bins:

Designed to fit a standard, 22" wide or wider open
top Scotsman Ice Storage Bin. Some examples
are:

BH360: Direct Fit

•

HTB555 - use KBT27

•

Bins with short or no baffles require the

•

addition of thermostat kit KSTAT-22 to lower
the ice level

Dispensers

ID150: Add adapter kit KBT42

•

HD22: Direct fit

•

Condensers

Single Circuit, 60 Hz: ERC111-1

•

Dual Circuit, 60 Hz: ERC211-1

•

Also, a Fan Relay Kit is needed when connecting
two ice machines to one condenser:

KCMR120 relay kit used with 115 volt 60 Hz

•

units

In addition, there may be other bins and
dispensers that can be used, check Scotsman’s
sales literature for application information.

Precharged Tubing:

•

25’ RTE25

•

40’ RTE40

•

75’ RTE75

BASIC INFORMATION

Dimensions

Model Number

CME456RS-1C 22“ x 24" x 28" 115/60/1

WxDxH
(w/o bin)

Basic Electrical
(volts/Hz/phase)

Use Condenser

ERC111-1A (1 ice
machine) or
ERC211-1A (2 ice
machines)

Use precharged tubing kits, RTE25 (25’) or RTE40 (40’) or RTE75 (75’). Select the length closest to
the needs of the particular installation.

June 2004

Page 2

Refrigerant
Charge
R-404A

192 oz 20 20

Minimum
Circuit
Ampacity

Maximum
Fuse Size

Condenser and Ice Machine Layouts

CME456R

Bin Stat
Thru Hole

12.88 in

32.7 cm

3.75 in

9.5 cm

Bin Stat
Bracket
Mounting
Holes

8.75 in

22.2 cm

Plan View

11.38 in

28.9 cm

1.25 in

3.2 cm

2.63 in

6.7 cm

4.00 in

10.2 cm

1.75 in

4.4 cm

16.7 in

42.4 cm

22.00 in

55.9 cm

Ice Opening

December 2000

Page 3

CME456R

Pre-Installation

Other Applications:

Check sales literature for additional information.

Note: Slope-front bins must have an internal baffle.
Scotsman BH375 has the required baffle, and the
BH260 does not need one. Baffle must be
approximately in the position shown in the diagram
below.

Baffle

12.0"

4.0"

Side View

Electrical:

Check the nameplate for electrical requirements.
The nameplate is located on the back of the ice
machine. If the information on the nameplate is
different from other published information, go by
the nameplate data.

Water:

There is no such thing as pure water. All water
contains some impurities. There are two ways
water carries the impurities: suspended and
dissolved. Suspended solids can be filtered out.
Dissolved solids must be diluted or treated. Water
filters are recommended to remove suspended
solids. Some filters also have treatment in them for
dissolved solids. Check with a water treatment
service for a recommendation.

Cube Ice machines use more water than what
ends up in the bin as ice. While most water is used
during ice making, a portion is designed to “rinse"
out the water system to keep hard water scale
from clogging up the machine. That water rinse,
combined with water filters, prolongs the times
between needed water system cleaning.

Service Technicians: All models covered here
come set from the factory with at a “Standard”
water rinse. Standard water rinse is designed to be
compatible with typical water conditions. The
machine may be adjusted to a different water rinse
after start up. If the prior ice machine worked
acceptably well with the local water conditions,
leave the machine at the factory setting. If severe
water conditions are present, and water filters do
not solve the problem acceptably, adjust the
machine to use more water. If water conditions are
excellent, adjust the machine to use less water.
See the Adjustments section.

While the model and
serial number are on
the nameplate, a

serial number plate
is located at the
front of the machine,
behind the front
panel and to the right

of the purge valve.

Nameplate, on back panel

Serial Number Plate, remove front

panel to locate.

Note: Water use adjustments are customer
convenience adjustments; they are NOT factory
defects and are NOT covered by warranty.

December 2000

Page 4

Location & Assembly

CME456R

Locate the ice machine indoors. A 6 inch minimum
clearance on the back and sides is required for the
proper operation and service of this machine.

Locate the remote condenser as close as possible
to the ice machine. See page 11 for details.

Unpacking and Assembly:

Begin with unpacking the ice storage bin. Remove
the carton, and using part of the carton as a
cushion, tip the bin on its back to remove the skid
and attach the legs or casters.

Note: This unit may not be stacked.

Return the bin to an upright position. Check the bin
top gasket for gaps and tears, fill any in with food
grade sealant prior to placing the ice machine on
the bin.

Note: If recycling a prior bin, be sure that the bin
top gasket is in good condition or seal the ice
machine to the bin with food grade sealant.

Level the top edge of the bin front to back and left
to right.

Cabinet Panel Removal:

1. Remove the front panel by removing the two
screws connecting the top of the front panel to the
machine, then pull out at the bottom.

2. Lift up at the front edge and push the top panel
back until it releases from the tabs connecting it to
the back panel.

If the ice machine has not been unpacked, do so
now. Remove the carton from the skid. Remove
shipping straps.

Remove the front panel and all packaging
materials.

After all packing materials have been removed
from the ice machine, lift or hoist the machine onto
the bin. Align the sides and back of the machine
with the sides and back of the bin.

Secure the ice machine to the bin with the two
metal straps and 4 bolts provided.

3. Remove two screws at the front of each side
panel, and pull them forward until they release
from the tabs connecting them to the back panel.

December 2000

Page 5

CME456R

Bin Control: Optional Installation

The normal bin control is the ice sensor system. A
bin thermostat may be required in some cases, It
must be field installed after the ice machine has
been placed on the bin.

Before starting, remove the front panel and any
baffle in the bin.

1. Place thermostat in machine behind the high
voltage box. Secure to existing holes with two
screws. Locate bin thermostat bulb.

6. Fasten the bracket to the bottom of the ice
machine with the two 3-pronged knobs supplied
with the unit.

7. Pull excess capillary tubing into the machine.

2. Route bulb thru routing tube (located between
the compressor and the reservoir).

3. Connect harness to bin thermostat and to
controller.

4. Locate bin thermostat bracket.

Routing Hole

8. Return the baffle to the bin and continue with
the installation.

Note: If the machine is located at an altitude higher
than 2,000 ft., adjust the thermostat by removing
the plastic cover and rotating the adjustment screw
per the table.

Bin Thermostat Altitude Correction Table

CW Turns of Range Screw (under plastic cover)

Feet Turns Feet Turns

2000 55

4000 160

o

o

8000 340

9000 385

o

o

5. Carefully position the thermostat bulb on the
bracket.

December 2000

Use This Table to Adjust Thermostat

Page 6

For The Installer: Remote Condenser

CME456R

Locate the condenser as near as possible to the
interior location of the ice maker.

Note: The location of the condenser relative to the
ice machine is LIMITED by the specification on the
following page.

Select the best available location, one that protects
the condenser from excessive dust, grease & sun.

Meet all applicable building codes.

Roof Attachment

Install and attach the remote condenser to the roof
of the building, using the methods and practices of
construction that conform to the local building
codes, including having a roofing contractor secure
the condenser to the roof.

Note: If using any other condenser besides the
ERC111 or ERC211, its use must be approved by
Scotsman, and a head pressure control valve must
be connected to the condenser coil.

Line Routing

Do not connect the tubing until all routing
and forming of the tubing is complete.
See the Coupling Instructions for final
connections.

3. Route the refrigerant tubes thru the roof
opening. Follow straight line routing whenever
possible.

If connecting two ice machines, be sure that the
tubes from ice machine #1 are connected to one
circuit of the condenser and the tubes from ice
machine #2 are connected to the other.

Note: Excess tubing may EITHER be coiled up
INSIDE the building OR cut out prior to connection
to the ice maker and condenser.

If the excess tubing is cut out, after re-brazing the
tubing must be evacuated prior to connection to
the ice maker or condenser.

If the excess tubing is to be coiled, spiral it
horizontally to avoid excess trapping in the lines.

Note: A 36" service loop may be placed behind the
ice machine.

5. Have the roofing contractor seal the holes in the
roof per local codes.

ERC111 Remote

Condenser

Electrical Power

Supply

If two CME456R ice machines are to be
installed, mark one as Ice Machine #1
and the other as Ice Machine #2. Tag
their refrigerant lines the same way.

1. Each set of pre-charged tubing lines

3

contains a

1

” diameter discharge line. Both ends of

2

“ diameter liquid line, and a

8

each line have quick connect couplings,
the end without access valves goes to
the ice maker.

Note: The openings in the building ceiling
or wall, listed in the next step, are the
minimum sizes recommended for
passing the refrigerant lines through.

2. Have the roofing contractor cut a
minimum hole for the refrigerant lines of
2“. Check local codes, a separate hole
may be required for the electrical power
supply to the condenser.

Caution: Do NOT kink the refrigerant
tubing while routing it.

Coil Excess

Tubing

Horizontally

Within the

Building

December 2000

Page 7

Typical Installation

CME456R

Remote Condenser Location

Use the following for planning the placement of the
condenser relative to the ice machine

Location Limits - condenser location must not
exceed ANY of the following limits:

Maximum rise from the ice machine to the

•

condenser is 35 physical feet
Maximum drop from the ice machine to the

•

condenser is 15 physical feet
Physical line set maximum length is 100

•

feet.
Calculated line set length maximum is 150.

•

Calculation Formula:

Drop = dd x 6.6 (dd = distance in feet)

•

Rise = rd x 1.7 (rd = distance in feet)

•

Horizontal Run = hd x 1 (hd = distance in

•

feet)
Calculation: Drop(s) + Rise(s) + Horizontal

•

Run = dd+rd+hd = Calculated Line Length

Configurations that do NOT meet these
requirements must receive prior written
authorization from Scotsman.

Do NOT:

Route a line set that rises, then falls, then

•

rises.
Route a line set that falls, then rises, then

•

falls.

Calculation Example 1:

The condenser is to be located 5 feet below the ice
machine and then 20 feet away horizontally.

5 feet x 6.6 = 33. 33 + 20 = 53. This location would

be acceptable

Calculation Example 2:

The condenser is to be located 35 feet above and
then 100 feet away horizontally.

35 x 1.7 = 59.5. 59.5 +100 = 159.5. 159.5 is

greater than the 150 maximum and is NOT
acceptable.

rd

22.87"

dd

17.15"

Max 35’

Max 15’

Remote

Condenser

Located ABOVE

Ice Machine

Remote

Condenser

Located BELOW

Ice Machine

hd

40.35"

Condenser Distance &

Location Schematic

December 2000

Page 8

Coupling Instructions

CME456R

The couplings on the ends of the pre-charged line
sets are self-sealing when installed properly.
Follow these instructions carefully.

These steps must be performed by an EPA
Certified Type II or higher technician.

Initial Connections

1. Remove the protector caps and plugs. Wipe the
seats and threaded surfaces with a clean cloth to
remove any possible foreign matter.

2. Thoroughly lubricate the threads, o-rings,
diaphragms and all internal coupling surfaces with
polyolester refrigerant oil.

Clean and Lubricate Couplings

3. Position the fittings on the correct connections
on the condenser and ice machine.

•

1

The

“ discharge line (schrader valve end)

2

goes to the remote condenser fitting marked
“discharge line”.

•

3

The

“ liquid line (schrod valve end) goes to

8

the remote condenser fitting marked “liquid
line”.

•

1

The

“ discharge line goes to the ice maker

2

fitting marked “discharge line”.

•

3

The

“ liquid line goes to the ice maker

8

fitting marked “liquid line”.

4b. Using two wrenches, one to rotate the swivel
nut and one to hold the tubing in place, tighten
each coupling.

It is CRITICAL that ONLY the NUT on the
pre-charged tube be turned, or the diaphragms will
be torn by the piercing knives and become loose in
the refrigeration system causing severe
operational problems.

Tighten Swivel Nut

Note: As the coupling is tightened, the diaphragms
in the quick connect couplings will begin to be
pierced. As that happens, there will be increased
resistance to tightening the swivel nut.

4c. Continue tightening the swivel nut until it
bottoms out or a very definite increase in
resistance is felt (no threads should be showing).
Do NOT overtighten.

5. Use a marker or pen to mark a line on the
coupling nut and unit panel. Then tighten the
coupling nut an additional one-quarter turn. The
line will show the amount that the nut turns.

6. After all connections have been made, and after
the liquid line valve has been opened (do not open
yet), check the couplings for leaks.

Note: The system charge is contained in the
receiver tank of the ice machine. Only “holding"
charges are present in the “pre-charged" tubing or
the condenser.

Final Connections:

4a. Begin to tighten the couplings together by
hand. Continue to turn the swivel nuts by hand
until it is certain that the threads are properly
engaged.

December 2000

Rotate Swivel Nut ¼ Turn More

Page 9

CME456R

Fan Relay Kit

When two CME456Rs are located near each other
and are connected to the same ERC211 remote
condenser, a fan relay kit, KCMR120 is required to
operate the condenser’s fan motor.

1. Attach the relay box of the KCMR120 to a
location that is convenient for installation and
future service.

2. Attach a solid earth ground wire to the ground
screw.

Electrical Shock Hazard

Disconnect Electrical
Power Before Beginning

3. Route the connecting wires from the first ice
machine's fan wires to the relay kit terminal strip
posts marked: No. 1 Ice Machine.

Put the Hot (line) wire on Terminal 1 and the

•

Neutral wire on Terminal 2.

4. Route the connecting wires from the second
machine's fan wires to the relay kit terminal strip
posts marked: No. 2 Ice Machine.

•

Put the Hot (line) wire on Terminal 3 and the
Neutral wire on Terminal 4

5. Attach wires at the fan relay kit terminal strip
marked: To Remote Fan, and route them to the
remote condenser electrical connection.

Terminals 2 and 4 must be connected to a

•

common leg (such as N).

B. After initial start up, test with a volt meter
(compressors must be ON).

1. Switch on ice maker #1, then ice maker #2.

2. Test with a volt meter between the terminals
and ground.

3. List the voltages and compare them to what
they should be.

Tested Voltage Should Be

Terminal #1 to ground: 104 to 126 volts

•

Terminal #2 to ground: near zero

•

Terminal #3 to ground: 104 to 126 volts

•

Terminal #4 to ground: near zero

•

Tested Voltage Was:

Terminal #1 to ground: _____

•

Terminal #2 to ground: _____

•

Terminal #3 to ground: _____

•

Terminal #4 to ground: _____

•

If the voltages are not correct:

A. Switch off ice maker number 2, and then switch
off ice maker number 1.

B. After the units have stopped, disconnect the

electrical power. Do all wiring with the
electrical power disconnected to BOTH ice
makers at the source.

C. Reverse the connections at the KCMR120
terminal strip that measured incorrectly.

6. Make the proper electrical connection at the
junction box.

Conform to all applicable codes.

Phasing: To be certain that a reliable installation

of the KCMR120 kit has been accomplished, a
check of the electrical phasing is required.

If the power is not connected properly the
relay will fail in a cycle or two and there may
be an electrical overload.

A. Before initial start up. Compare the illustration
of the KCMR120 terminal strip to the connections
at the KCMR120:

•

Terminals 1 and 3 must be connected to a
common leg (such as L1).

December 2000

D. Reconnect electrical power.

KCMR120 RELAY BOX

Page 10

Electrical

CME456R

All models must be installed with the correct wire
size and type per the National Electric Code.
Locate the nameplate on the back of the cabinet
and find the numbers for Voltage, Phase, Minimum
Circuit Ampacity and Maximum Fuse Size. Either
fuses or HACR type circuit breakers may be used.

The ice maker is designed to operate on its own
electrical circuit and must be individually fused.
Voltage variation must not exceed the limits listed
on page 2.

The remote condenser is designed to be powered
from the ice machine. A separate knockout hole
has been provided in the ice maker electrical
junction box.

Remote

Condenser

Note: Central Condensers connected to more than
one refrigeration system will likely have a wiring
scheme to control the fan motor. Follow those
directions for condenser wiring.

Electrical connections are made in the junction box
in the back of the cabinet.

1. Remove the junction box cover.

2. Knock out both holes for a field supplied strain
relief.

3. Install wires and strain reliefs per code. Note:
Condenser fan motor wires are tagged.

4. Connect to wires and secure ground wire to
ground screw inside junction box.

All external wiring should conform to the national,
state and local electrical code requirements.
Usually an electrical permit and the services of a
licensed electrician will be required.

Interconnecting

Wires

Power

Supply

Power IN

Power OUT

December 2000

Page 11

CME456R

Plumbing

All models require an adequate potable water
supply and a gravity drain. The recommendations
for tubing are:

Water supply to be

•

Drain to be

•

3

" OD.

4

3

" OD.

8

Note: When replacing a prior ice machine, do not
take a short cut and reuse the old inlet and drain
system. INSTALL A NEW SYSTEM.

Supply:

3

All models have 1 water supply connection, a

"

8

male flare at the back of the cabinet. Connect to
cold potable water that has adequate pressure.

Note: Using water supply tubing smaller than

3

"

8

will cause severe operational issues.

Water Filters:

The water filters must flow at least 1.25 GPM or
they will cause severe operational issues. Check
with the filter manufacturer. When replacing a prior
ice machine, do NOT assume that the water flow
capacity of the filter will be adequate.

All Drain Tubing Material must be RIGID.
Flexible tubing will eventually cause a
restricted drain.

Drain:

3

All models have 1 gravity drain connection, a

"

4

FPT fitting at the back of the cabinet. Use only
RIGID TUBING. Flexible tubing may be easily
kinked or become cracked.

The drain tube must be vented at the back of the
cabinet. Use an 18" high vent.

The ice storage bin will have a drain out the back
or base, depending upon the model.

The drain for the ice machine and the ice storage
bin must be SEPARATE or the ice machine’s drain
water may run into the bin and MELT THE ICE.

Insulation is recommended for the ice machine
reservoir and bin drains.

Follow all applicable codes

Bin Drain

Electrical OUT to

Condenser Fan

Electrical IN

Water IN

Water OUT

December 2000

Page 12

After Utility Connections

1. Wash out the bin. If desired, the interior of the
bin could be sanitized.

2. Locate the ice scoop (if supplied) and have it
available for use when needed.

3. Switch on the electrical power. Do not start the
machine for 4 hours.

4. Go thru the final check list (below).

Final Check List:

___ 1. Is the unit located indoors in a

controlled environment?

___ 2. Has the correct remote condenser been

properly located and mounted?

___ 3. Has the correct electrical power

(voltage and phase) been supplied to
the machine?

CME456R

___ 4. Have all the water supply connections

been properly made with the correct
size tubing?

___ 5. Have all the drain connections been

properly made?

___ 6. Has the unit been leveled? Level the

unit at the bin.

___ 7. Have all unpacking materials been

removed?

___ 8. Is the water pressure adequate?

___ 9. Is the machine secured to the ice

storage bin?

___ 10. Is the bin control system been properly

installed?

___ 11. Have the drain connections been

checked for leaks?

___ 12. Has the bin interior been wiped clean or

sanitized?

___ 13. Have any water filter cartridges been

replaced?

___ 14. Check all refrigerant lines and conduit

lines, for vibration or rubbing and
possible failure. Adjust as needed.

___ 15. After 4 hours of electrical power,

proceed to Initial Start Up.

December 2000

Page 13

CME456R

Component Location and Function

Reservoir: Contains the water used to make ice.

Water Inlet Valve: Opens to allow water into the

reservoir.

Freezing Compartment: Location of the
evaporators. Ice forms on the evaporators, and is
released when warmed up during the harvest
cycle. The freezing compartment is fully insulated
for maximum efficiency.

Cube Deflector: The slots in the inclined deflector
allows the water falling from the evaporators back
into the reservoir, but when ice falls during harvest,
the ice slides off into the bin.

Harvest Bypass Valve: Injects additional
refrigerant into the harvest system.

Receiver

Liquid Line

Valve

Water Pump: Forces the water from the reservoir

to the top of the evaporator(s). The motor is kept
separate from the water to minimize contact with
moisture.

Hot Gas Valve: Closed during freeze, it opens
during harvest to divert hot discharge refrigerant
gas into the inlet of the evaporators.

Purge Valve: Opens during the first part of
harvest, when the water pump restarts the water in
the reservoir is diverted to the drain.

Check Valves: Liquid and Discharge lines contain
check valves. These control refrigerant migration
during the Harvest and Off cycles.

Freezing

Compartment

Harvest

Bypass Valve

Inlet Water

Valve

Controller

Water Level

Sensor

Water Pump

December 2000

Page 14

AutoIQ Controller

S

CME456R

Indicator Lights:

Bin Full: On when bin is full, goes on and

•

off as ice falls during a harvest cycle.
Freeze: On when the unit is in the Freeze

•

cycle, blinks when a freeze cycle is pending.
Harvest: On when the unit is in the Harvest

•

cycle.
Clean: On when the unit is in the Clean

•

cycle.
Off: On when the unit has been switched off,

•

blinks when the machine is preparing to shut
off.

Water: On when the controller has identified

•

a problem with the water system.
Refrigeration: On when the controller has

•

identified a problem with the refrigeration
system.

LOW VOLTAGE IN/OUT

WATER VALVE

HOT GAS VALVE

PURGE VALVE TIMER

CONTACTOR COIL

Cycle Definitions:

Freeze: The refrigeration system is

•

operating to remove heat from the
evaporators. The compressor, remote fan
motor and water pump are ON.

Harvest: The refrigeration and water

•

systems are operating to harvest the ice
cubes. While the compressor and fan motors
are on for the full cycle, the water pump will
be off at the beginning and the inlet water
valve will switch off before the end.

Clean: Water valve opens to fill the

•

reservoir. The Water pump starts. The Clean
indicator light is switched ON. A manually
initiated rinse cycle flushes the system.

89

HI VOLTAGE IN/OUT

WATER PUMP

THERMOSTAT

FUTURE USE

RESERVOIR & DISCHARGE

LINE THERMISTORS

ICE SENSOR

ICE SENSOR

RESERVOIR WATER

LEVEL SENSOR

FACTORY USE

7

6

5

4

3

2

1

PUSH BUTTON

CONTROL SWITCHE

INDICATOR LIGHTS:

BIN FULL

FREEZE

HARVEST

CLEAN

OFF

DIAGNOSTIC LIGHTS:

WATER

REFRIGERATION

December 2000

Page 15

CME456R

Initial Start Up

1. Remove the front and left side panels.

2. Locate and open the liquid line valve.

Open By Turning

Stem Fully Out

3. Double check quick-connect couplings for leaks.

4. Locate the AutoIQ Controller.

5. Check for electrical power. The Off light on the
controller should be glowing.

6. Open the water supply valve.

7. Push and release the Freeze cycle push button
(the Freeze indicator light will blink until the
compressor starts). The next several operations
are automatic.

Initial Start (30 seconds)

•

The Freeze light will begin to blink.

•

The hot gas solenoid valve will be open.

•

The purge valve will be open

•

The water pump will be on

•

After 30 seconds, the hot gas valve closes

•

The purge valve will shut and the inlet water
valve will open to fill the reservoir. The inlet
water valve shuts off when the reservoir is
full.

•

The compressor & remote fan motor start.

Freeze Cycle

The Freeze indicator light will come on. The unit
will be in a Freeze cycle for many minutes. Slush
may appear in the reservoir, it is temporary and
normal.

•

The pump will stop for a few seconds a few
minutes into the freeze cycle

•

The freeze cycle will continue until the water
level in the reservoir drops to its factory set
point, the first time that happens the water
valve will re-fill the reservoir. The second
time it happens in a freeze cycle starts the
Harvest Cycle.

Harvest Cycle:

•

The Harvest indicator light will be ON,

December 2000

Page 16

The hot gas valve will open.

•

The purge valve will be open for 74 seconds.

•

The water pump will switch off. The pump

•

will restart part way thru the harvest cycle.
The purge valve closes.

•

The Inlet water valve will open for a short

•

time
The Bin Full indicator light will go on and off

•

as ice falls from the evaporators.

8. Machines are shipped from the factory with the
purge level set to accommodate average water
conditions. To achieve optimal machine
performance, set the purge level to the minimum
setting.

Note: While the amount of water purge is
adjustable, only those installations with a water
supply known to be excellent (very low TDS)
should adjust to the minimum setting. See the next
page for purge adjustment procedures.

9. After about 6 minutes (first cycle after any
restart) the machine will return to a freeze cycle.

Note: After the first harvest, the controller adjusts
the harvest time as needed to release all ice.

10. The reservoir refills at the beginning of Freeze.

11. Fill out the Customer Evaluation and Warranty
Registration. Send it to Scotsman.

12. Return all panels to their normal positions.

13. Inform the user of the location and telephone
number of the local service company. Inform the
user of the required maintenance of the machine.

Operational Notes:

1. The machine will only shut off on Bin Full at the
end of the Harvest Cycle after the bin fills. That
last harvest cycle will be about 6 minutes long.

2. After switching off on Bin Full, if ice is removed
from the bin, the machine will not restart until it has
been off for 4 minutes. If the Freeze button is
pushed, the machine will restart immediately.

3. If the bin controls sense a bin full signal before
any water is used (float stem up), the machine will
shut off on bin full.

4. When shutting off, the compressor will run for 30
seconds (everything else will be off) and then
switch off.

Adjustments

CME456R

If there was a problem during Initial Start
Up:

If a diagnostic light came on, check the following.

1. Water.

A water error could have been determined by the
AutoIQ Controller if the inlet water valve does not
fill the reservoir or if the water pump does not start
and lower the water level in the reservoir. If either
condition is found, the water error light will be
switched on and the machine will Shut Down.

2. Refrigeration.

A refrigeration error could have been determined
by the AutoIQ Controller if the water temperature
did not drop during the freeze cycle. The
Controller will next check the compressor
discharge temperature. If the discharge
temperature is too low, the refrigerant error light
will be switched on, and the machine will Shut
Down.

Note: The machine can be reset and restarted by
pushing and releasing the Off push button switch,
and then pushing and releasing the freeze push
button switch.

Thermostatic Expansion Valve:

The TXV is not adjustable, do not attempt to adjust
it.

How to Adjust the Amount of Water Purge

Adjustment is done by use of the control buttons
on the AutoIQ Controller. Examine the next section
to become familiar with the AutoIQ Controller
before beginning.

1. If the machine is on, push and hold the OFF
button for more than 3 seconds, then release it.
This switches the machine Off.

2. Push and hold the OFF button for more than 3
seconds (just until all Lights flash on) then release
it. Do not hold it in it too long.

3. Examine the green Lights. They should have all
flashed once, then certain ones will have turned on
to indicate which purge level the machine is set at.
There are 5 levels of purge available:

1. Maximum Purge is when All 5 lights are

•

ON. Use for extreme water conditions. Note:
This setting may extend the Harvest cycle
and reduce capacity.

2. Heavy Purge is when these 4 lights are

•

ON: Freeze
moderate to severe water conditions. This
setting may extend the Harvest cycle and
reduce capacity.

•

3. Standard Purge (factory setting) is when
these 3 lights are ON: Harvest
Use for typical water conditions.

•

4. Moderate Purge is when these 2 lights
are ON: Clean
conditions.

•

5. Minimum Purge is when this light is ON:
. For excellent water conditions.

Off

Adjust by pushing and releasing the Freeze button.
Pushing and releasing the Freeze button increases
the purge one level up to the maximum, then it
goes to the minimum.

, Harvest, Clean,Off. Use for

, Clean,Off.

,Off. This is for good water

4. The machine will automatically restart after 60
seconds of no switch inputs, or restart the machine
by pushing in and holding the Off button for more
than 3 seconds, then releasing it. The unit will then
be Off. From there the machine may be placed in a
freeze cycle by pushing and releasing the Freeze
button.

December 2000

Page 17

CME456R

How To Operate The AutoIQ Controller

The AutoIQ Controller is a
microprocessor based device that
receives input from several sources
and switches various components on
and off.

Its manual control is thru the use of
the Push Button Control Switches

1. Freeze Button. Pushing and
releasing this button starts or restarts
the machine. The AutoIQ Controller
remembers what cycle it was last in
and returns to that cycle.

2. Harvest Button: Pushing and
releasing this button will cause the
machine to go directly to a Harvest
Cycle. Can be done from Freeze or
Off. The machine will switch Off at the
end of the Harvest cycle.

3. Clean Button: Pushing and
releasing this button will cause the
machine to empty the reservoir, refill
and leave only the water pump on for
circulation of ice machine cleaner.
After the ice machine cleaner has
circulated for about 10 minutes a
second push of this button will switch
on the rinsing system to flush out the
dissolved scale and ice machine
cleaner.

4. Off Button: Pushing and releasing
this button will switch the machine
OFF at the end of the next cycle. If the
button is pushed and HELD for more
than 3 seconds, the unit will switch off
immediately.

7

6

5

4

3

2

1

89

PUSH BUTTON

CONTROL SWITCHES

INDICATOR LIGHTS:

BIN FULL

FREEZE

HARVEST

CLEAN

OFF

DIAGNOSTIC LIGHTS:

WATER

REFRIGERATION

To Reset Errors: First push and
release the Off button, then push and
release the Freeze button.

December 2000

Page 18

CME456R

r

How The Electronic Cuber Works

This section is intended for the technician. It is not necessary for the normal operation and maintenance
of the machine.

Refrigeration System:

The refrigeration system is similar to that of most
commercial cube ice machines. Heat is removed
from the water and discharged out the condenser
during the freeze cycle. As liquid refrigerant
passes thru each Thermostatic Expansion Valve, it
enters the bottom of the evaporators, and ice will
form at the bottom first.

When cubes need to be released (Harvest) the Hot
Gas Valve is opened and Hot discharge gas flows
from the compressor through the check valves to
the evaporator inlets. At the same time, a Harvest
Bypass Valve opens for a few seconds to add the
refrigerant needed for harvest. After that the
Harvest Bypass Valve and the closed Discharge
Check Valve keeps the refrigerant in the
condenser out of the Hot Gas Circuit.

Discharge Line

Accumulator

Check
Valve

Remote Condenser

Head
Pressure
Control
Valve

Receiver

This warms up the evaporators and the surface of
the ice frozen to the evaporator surface melts. Ice
then falls into the bin.

The liquid line Check Valve prevents liquid
migration at low ambients during the Off cycle.

TXV

Hot Gas

Valve

Check
Valve

Check
Valve

TXV

Harvest

Bypass

Valve

Process

Port

Compressor

Heat

Exchange

Suction

Refrigeration Schematic

December 2000

Page 19

Evaporato

Evaporator

CME456R

How The Electronic Cuber Works

Water System:

Freeze:

The water pump forces water to the top of the
evaporators. The un-frozen water falls thru the
cube deflectors and back into the reservoir. As
water is turned into ice, the water level in the
reservoir falls, and the machine will re-fill the
reservoir once during the freeze cycle.

At the point where the cubes are fully formed, the
water level sensor indicates to the AutoIQ
Controller that it is time to begin the Harvest cycle.

Harvest:

At the beginning of Harvest, the water pump shuts
off and the purge valve opens. The purge valve
remains open for 40 seconds. No water will drain
until the water pump restarts. The water pump will
start at a variable time depending upon the amount
of water rinse that has been set.

After the purge valve has closed, the inlet water
valve opens and water flows into the ice machine.
The water valve will NOT be open the complete
length of the harvest cycle.

The inlet water valve will “top off” the reservoir at
the beginning of the next freeze cycle.

The AutoIQ Controller operates the ice machine by
monitoring several input measures and switching
various loads on and off.

Controller Inputs:

1. Reservoir water temperature. This is
measured by a thermistor located in the water
pump outlet.

2. Discharge line temperature. This is measured
by a thermistor located on the compressor
discharge line.

3. Water level. This is measured by an infrared
sensor and float. The float rises and falls with the
water level, and switches the sensor on and off as
it moves.

4. Bin fill level. This is measured by a set of
electric eyes in the cube outlet port. If ice fills the
bin, it will block the “eyes".

Some units are equipped with a bin thermostat,
those units use the thermostat to switch the
machine on and off. The electric eyes in the cube
outlet port will also control the machine if the bin
thermostat sticks in an ON position.

5. Time. The controller measures and compares
how long it takes for various events to happen. It
stores that data for future reference.

Controller Outputs:

A. 24 volt:

•

1. Lights

•

2. Inlet water valve

•

3. Hot Gas Valve

•

4. Contactor Coil

•

5. Harvest Bypass Valve Coil

B. High Voltage

•

1. Water Pump

•

2. Purge Valve

December 2000

Page 20

Technicians Only: Freeze Cycle Sequence

CME456R

Assuming the machine has been operational, the
Freeze cycle begins with the end of the Harvest
Cycle:

Water Inlet Valve is Closed

•

Water Pump is ON

•

Compressor is ON

•

Hot Gas Valve is Open

•

AutoIQ Controller Operation, Beginning
freeze:

1. Switches on Freeze indicator light and shuts off
the hot gas valve.

2. Opens the water valve to top off the reservoir.
The controller checks that water fills the reservoir,
if it does not fill up within 130 seconds, the
controller shuts the machine down. It will
automatically try to restart in 20 minutes.

3. Measures and stores the discharge
temperature.

4. If the discharge temperature exceeds the design
maximum, shuts the machine down on a
Refrigeration Error.

5. Checks for a “bin full" signal throughout the
cycle.

6. Measures the reservoir water temperature. If the
machine is operating correctly, the reservoir water
temperature will fall at a standard rate. The AutoIQ
Controller will be checking to see if the water
temperature fall matches that rate.

If not, it re-checks the discharge line temperature.
If too low, it Shuts Down on a Refrigeration Error. If
the discharge temperature is acceptable, the water
system is checked by shutting off the water pump
and determining if the water level goes up enough.
If it does not, the inlet water valve will open again
to fill it. If, after restarting, the water level does not
drop, it is assumed that there is a water pump
problem and the machine Shuts Down on a Water
Error.

If the water level does “measure up" the water
pump is restarted and the AutoIQ Controller then
measures how long it takes to lower the water
level. If the water level does not fall, the machine
Shuts Down on a Water Error.

8. As the machine makes ice, the water level in the
reservoir will ultimately fall to the Harvest Level.
The first time that happens per freeze cycle the
inlet water valve is re-opened and the reservoir is
refilled. The next time it happens, the unit will go
into a harvest cycle.

Note: If the freeze cycle exceeds the preset
Maximum (45 minutes), the Controller will Shut
Down the machine and switch on the Refrigeration
Light.

9. The end of Freeze cycle will see the machine in
this state:

Water level = below harvest position

•

Water inlet valve will be off

•

Water pump will be ON

•

Compressor will be ON

•

Hot gas valve will be off

•

At this point Harvest begins and the AutoIQ
Controller switches the Harvest indicator light ON.

Restarts:

If the machine is restarting after it has shut off
because the bin was full, the first freeze cycle
sequence is like this:

1. Purge valve is open.

2. Pump starts.

3. Purge valve closes.

4. Water valve opens to fill the reservoir.

5. Compressor starts.

Note: If there is a power interruption, after power is
restored the machine will restart, go thru a brief
Freeze cycle and go thrua6minute Harvest cycle.

Error Restarts:

The machine automatically attempts to restart 50
minutes after a shut down. If another problem
occurs in the next cycle, the machine will attempt
one more restart. If another problem occurs in the
next cycle, the machine will shut off and must be
manually reset.

7. Once per freeze cycle the machine will shut off
the water pump. It only does this when the water
temperature reaches a preset minimum. The pump
will only be off for a few seconds.

December 2000

Page 21

CME456R

Technicians Only: Harvest Cycle Sequence & Other Notes

Harvest

The Purge Valve will be open for 40 seconds.

The water pump shuts off, it will restart before 40
seconds, the restart time is based on the Purge
Level Setting.

The pump restarts and pumps water out of the
reservoir until the purge valve closes.

The inlet water valve will stay on for about 30
seconds to add enough water to assist with
harvest.

The Hot Gas Valve will be open for the entire
length of the Harvest Cycle.

The Harvest Bypass Valve will be open for a few
seconds (between 4 and 12, depending upon
discharge temperature) at the beginning of the
Harvest Cycle.

During the Harvest Cycle, ice will be falling from
the evaporators and between the ice sensor’s
electric eyes. The AutoIQ Controller monitors the
ice falling and uses that information to determine
the next harvest cycle length.

The first Harvest after a restart will take about 6
minutes to establish a base line, then the time it
took to release that ice is used to determine the
next harvest cycle’s length.

The maximum harvest time is 14 minutes.

Bin Thermostat:

In normal ambients the thermostat will react to ice
on the bulb in a few seconds. Reaction after
removal will take about a minute under normal
conditions, and longer in colder rooms.

Diagnostic Light Code Table

If a Diagnostic
Light

Blinks once and
repeats

Blinks twice and
repeats

Blinks three
times and
repeats

Is ON all the
time

Both ON all the
time

Water Light

Water pump will
not start

Lack of water fill

not used

Water valve
leaking thru
rapidly

Check for thermistor set unplugged
or failed

Note: Diagnostic lights remain on until the
controller is manually reset or until it successfully
restarts the machine.

Refrigeration
Light

Very long ice
harvest

No harvest of
ice

High Discharge
Temperature

Check for low
discharge
temperature or
long freeze
cycle

If no cubes fall (or are sensed) by the end of the
Maximum Harvest Time, the machine senses a
Refrigeration error. If the next cycle also produces
a Refrigeration error, the machine will shut down.

Note: The last Harvest cycle before shutting off on
Bin Full will be about 6 minutes long.

Note: The machine will not restart for 4 minutes
after switching off on Bin Full, unless the Freeze
button is pressed.

Bin Full: The controller will switch on the
compressor for 30 seconds after 25 hours of off
time to keep refrigerant out of the compressor oil.

Continuous Run Time

A unit that operates 24 hours a day 7 days a week
is too small for the user’s needs. To maintain
harvest integrity, the controller will extend the
harvest time to 6 minutes every 15th consecutive
harvest cycle.

December 2000

Page 22

CME456R

Sanitation and Cleaning

It is the User’s responsibility to keep the ice machine and ice storage bin in a sanitary condition.
Without human intervention, sanitation will not be maintained. Ice machines also require occasional
cleaning of their water systems with a specifically designed chemical. This chemical dissolves mineral
build up that forms during the ice making process. Sanitize the ice storage bin as frequently as local
health codes require, and every time the ice machine is cleaned and sanitized.

The ice machine’s water system should be cleaned and sanitized a minimum of twice per year.

In Place Cleaning of the Water System:

1. Remove all ice from the bin.

2. Remove the front panel.

3. Push and release the Harvest button (this releases
any ice on the evaporators and warms them up).

4. Wait for the machine to finish the Harvest cycle (the
machine will stop).

5. Remove the freezing compartment cover and both
inner splash panels.

6. Remove the sump cover by unplugging the wire
harness from the water level sensor, then removing the
screw holding the cover to the reservoir.

Unwind the wires from the sump cover and lift the sump
cover and water level sensor up & out of the machine.

7. Pull the float off the float stem. Squeeze the water
sensor mounting tabs together and remove the sensor
from the sump cover.

8. Remove the cube deflector from the machine by
lifting it up at the front, rotating it 90
pulling it out of the machine.

9. Place the cube deflector, sump cover, float, float
stem and both inner splash panels into a separate,
clean container.

10. Mix a solution of 8 ounces of Scotsman ice machine
cleaner and 1 gallon of warm (95-115
the solution to scrub the cube deflector, float, float stem,
sump cover & splash panels in the separate container.

11. Reassemble the water level sensor to the sump
cover. Insert float stem through sensor and push float
onto stem. Reconnect sensor wires and place assembly
onto reservoir.

o

clockwise, then

o

F.) water. Use

Scotsman Ice Machine
Cleaner contains acids.
Acids may cause burns.

If concentrated cleaner
comes in contact with skin,
flush with water.

If swallowed, do NOT
induce vomiting. Give large
amounts of water or Milk.
Call Physician
immediately. Keep out of
the reach of children.

12. Push and release the Clean button. The Clean
indicator light will blink and the pump will restart.

13. After water stops flowing in, lift sump cover and pour
12 ounces of Scotsman Ice Machine Cleaner into the
reservoir water. Return the sump cover and freezing
compartment cover to their normal positions.

14. After the ice machine cleaner has circulated for 10
minutes, push and release the Clean button. This starts
the rinsing process. The Clean indicator light will be
ON. Note: The rinse process flushes any residual
cleaner out of the ice machine’s water system.

15. Continue the rinsing process for 20 minutes, then
push the off button to switch the machine off.

16. Go to the next step to sanitize the machine or go to
step 23 to finish the cleaning process.

17. Mix 2 gallons of Sanitizer solution. Follow local
codes for Sanitizer.

Note: A possible sanitizing solution may be made by
mixing 1 ounce of liquid household bleach with 2
gallons of warm (95-115

18. Push and release the Clean button again.

19. After water stops flowing in, pour 24 ounces of
Sanitizer solution into the reservoir water.

20. After the solution has circulated for 10 minutes push
and release the Clean button. This starts the rinse
process. Sanitize the ice storage bin while waiting.

21. Continue the rinsing process for 20 minutes, then
push the off button to switch the machine off.

22. Remove the freezing compartment cover and spray
or wash all interior surfaces of the freezing
compartment including the inside of the cover with
sanitizer solution.

23. Repeat step 6 and thoroughly immerse the splash
panels, float, float stem, sump cover and cube deflector
in the sanitizing solution.

24. Return the cube deflector, inner splash panels,
water sensor, float and sump cover to their original
positions. Secure sump cover with the original screw.

25. Reconnect wire harness to water level sensor.

26. Return the freezing compartment cover to its
original position. Push and release the Freeze button.

27. Return the front panel to its normal position and
secure it to the machine with the original screws.

o

F.) potable water.

August 2008

Page 23

CME456R

Additional Maintenance

Additional Maintenance: Water Distributors

It may become necessary to remove the water
distributors from the top of the evaporator and
clean (de-mineralize) them outside of the ice
machine.

1. Remove front panel.

2. Push and release the OFF button.

3. Remove the evaporator cover.

4. Lift the water distributors up at the center until
they snap apart.

Water Level Sensor

Clean the lenses inside the water level sensor.

1. Remove the sensor from its installed position.

2. Remove dust cover.

3. Wipe lenses clean with a cotton swab.

Water

Channels

5. Repeat for all evaporators.

6. Examine the top of the evaporators. The Water
Distribution Channels must be free from mineral
build up. If build up is evident, scrub the channels
with Scotsman Ice Machine Cleaner and a plastic
bristle brush.

7. Examine the water distributors. Although they
are made of a material that is resistant to mineral
build up, some may be present. Soak or scrub the
distributors in or with a solution of Scotsman Ice
Machine Cleaner and warm potable water.

8. Return the water distributors to their normal
installed position.

9. Push and release the clean button to flush the
water system.

10. After the machine stops, push and release the
Freeze button.

4. Reverse to reassemble.

Dust Cover

Lenses

11. Replace the evaporator covers.

12. Replace the front panel.

December 2000

Page 24

Additional Maintenance: Inlet Water Valve Screen

CME456R

The inlet water valve has a screen on its inlet side
to keep debris from flowing into the valve. In some
cases, this screen may become clogged or
restricted by debris build up. Check for the proper
water flow:

Flow rate is 1.25 G.P.M.

1. Remove front panel.

2. Obtain a 16 ounce cup and a watch.

3. Pull the water discharge tube out of the
reservoir and place it in the cup.

4. Push and release the Harvest button.

5. If working properly, the water valve will fill an 16
oz cup in about 10 seconds. Be prepared to push
the Off button! If it does not, the water valve inlet
or other water device is restricted.

To Check the Inlet Water Valve Screen.

1. Disconnect the electrical power.

2. Shut off the water supply.

To Sanitize the Ice Storage Bin

1. Remove all ice.

2. Remove baffle.

3. Switch ice machine OFF or wait for it to be in a
cleaning cycle.

4. Mix a 1 gallon solution of warm (95-115oF.)
water and sanitizer. Follow local codes for
sanitizer.

5. Wash or spray the entire interior of the ice
storage bin with the sanitizer solution. This
includes the bottom of the ice machine and the
inside of the door, the door gaskets (if any) and
door frame.

6. Pour excess sanitizer into the bin to flush the
drain system.

7. If the approved sanitizer requires a rinse, rinse
all interior surfaces with potable water.

3. Remove the front panel.

4. Unplug the electrical connection of the inlet
water valve.

5. Remove the screws holding the inlet water valve
to the cabinet.

6. Remove outlet tube from inlet water valve.

7. Rotate inlet water valve from inlet fitting and
remove valve from machine.

8. Examine the inlet screen, if dirty, brush off
screen. Note: Screen is not replaceable, and may
only be removed by taking off the covering
bracket. The bracket forms part of the inlet water
system, and must be water tight to the valve body,
removal is not recommended.

9. Reverse to reassemble.

To drain reservoir (if desired):

1. Remove front panel.

2. Push and hold the Off button.

3. Push and hold the Clean button until the
reservoir is empty.

4. Push and release Freeze button.

5. Return the front panel to its original position.

December 2000

Page 25

CME456R

Additional Maintenance: Ice Sensors, Condenser

The ice sensors use a system of infrared emitting
and receiving components to sense the build up of
ice in the bin. They are located at the bottom of the
ice outlet port. They must be free of mineral build
up to function properly. To check:

1. Remove front panel.

2. Push and release the harvest button.

3. Wait for the machine to stop.

Upper Splash

Cover

Lower Splash

Cover

5. Locate the
front ice sensor.

Push the sensor
from the front (at
the wire area) to
the back until it
releases from the
holder.

6. Locate the
back ice sensor
Pull on the
rectangular tab to
release it from its
mounted position.

7. Examine the bottom of the brackets, there are
two sensors in each bracket, check that they are
clear of mineral build up. They may be wiped clean
with ice machine cleaner to assist in removal of the
build up.

Note: Do NOT use abrasive materials or cleaner
on the ice sensor lenses. A soft toothbrush works
well to get into the hard to reach spots.

Back Ice Sensor Port (step 6)

4. Remove the evaporator cover.

8. Reverse steps 1-6 to reassemble.

To Clean the Remote Air Cooled
Condenser

1. Disconnect and lock out the electrical power.

2. At the remote condenser, check for loose debris
on the roof, remove any near the condenser.

3. Check the fan blade and condenser for grease
or dust build up. Brush the intake surfaces
(outside) of the condenser coils with a nylon brush
to remove surface dirt. Use a fin comb to
straighten any bent fins.

Note: Air flow is UP, towards the fan. If grease is
present, use coil cleaner on the condenser. Be
sure to wipe up any excess coil cleaner.

4. Reconnect the electrical power.

December 2000

Page 26

Lens Location in Ice Sensor

Service Diagnosis: Diagnostic Light Analysis

Problem or Symptom Possible Cause Probable Correction

Machine is off Bin is full Use some ice

Bin full light is ON, no ice
in cube port

Bin thermostat is closed Check thermostat

Power is off, check
Lights.

Transformer is open If all Lights are out and there is power, check

Unit has been switched
off or has finished a
Clean cycle, Off Light is
glowing

Unit has Shut Down Check for Refrigeration or Water Error

Unit is off on a Water
Error

Unit is off on a
Refrigeration Error

Unit runs and both
Diagnostic lites are ON

Same, only 1 light on Reservoir temp. wrong Check water temp. and sensor.

Water supply inadequate Check water Light, if the Light blinks 2 times

Water pump malfunction Check that pump hose is attached and if pump

Water level sensor may
have failed.

Low discharge or long
freeze cycle

Harvest problem Check refrigeration Light. If the Light blinks

High Discharge Temp Check refrigeration Light. If the Light blinks 3

Unit does not go into
harvest - exceeds
maximum freeze time

Exceeds maximum
harvest time

Temperature sensors
out of range

Check optional thermostat, check ice sensor
lens for scale.

If all Lights are out, check power supply,
restore power if off

transformer output for 24 vac

Push and release Freeze button

and repeats, check the water inlet valve for
proper water flow.**

is plugged in and working.

Check float stem, reset machine. If it will not
reset or gives another water error and
everything else is OK, replace the water level
sensor.

Check refrigeration Light. If the Light is
glowing, there is a probable refrigeration
problem - fan motor could have failed.

once and repeats, look for a harvest problem.
where some cubes were sensed.**

Check refrigeration Light. If the Light blinks two
times and repeats, look for a harvest problem. ­no cubes sensed**

times and then repeats, check for a reason for
high discharge temperatures - fan motor hot
ambient.

Push and release Off button. Push and release
Freeze button. Check operation.

Push cube size float down and check
operation.

Check for cause of long harvest cycle**

Replace the temperature sensor set (water and
discharge).

CME456R

* Machine may be reset by pushing and releasing the Off button, then pushing and releasing the
Freeze button. ** See following pages

December 2000

Page 27

CME456R

Service Diagnosis

Problem or Symptom Possible Cause Probable Correction

Unit is off because of a
“Harvest Problem”

Cubes are too large Cube size control float is

Cubes are too small Not enough water Check for leak in reservoir

Low ice capacity Dirty condenser Clean condenser

Unit does not shut off Ice sensing system may

Ice sensors did not sense
ice falling, unit stayed in
harvest until the maximum
harvest time ran out.

Bin controls or AutoIQ
Controller may have failed.

Other components may
have failed

sticking.

Inlet water valve leaking
thru (slowly)

Recirculation of air Block air re-circulation or move condenser

Low refrigerant charge Check system. If there is a low charge, find

Too much water Check for inlet water valve leak thru

have failed.

Check ice sensors. If the bin full light is on or
blinking the bin controls may be dirty. Clean if
dirty. The board and bin controls may also
need to be checked.

Check evaporators for lime scale build up.
Clean evaporators and bin controls if dirty.

Push and release Off button. Push and
release Freeze button. Check machine
operation. Check if ice is made and harvests.

See “Unit does not shut off” below..

Check the next page

Check/clean

Check hose from water valve for slow drip.
Replace valve if dripping.

Check for a leak thru the purge valve

the leak, recover the refrigerant, repair the
leak, replace the dryer, evacuate and weigh in
the nameplate charge.

Check controls. Unplug thermostat and check
bin full light, if off, place something between
the electric eyes. The bin full light should
begin to blink (after 20 seconds of continuous
blockage it will glow steadily). If not, check
operation of electric eyes by unplugging #4
and jumping out the two pins on the controller
(touch the tool to the cabinet to discharge
static electricity before contacting the
controller). If the bin full light blinks, replace
the bin controls. If it does not blink, replace
the controller. Note: Leaving #4 unplugged
and jumped for 20 seconds will shut the
machine down on a bin full (at the end of the
harvest cycle). It will restart after 4 minutes or
may be reset by pushing the Freeze button.

December 2000

Page 28

Service Diagnosis: Components

Problem or Symptom Possible Cause Probable Correction

Fan motor does not
turn.

Pump motor does not
turn

Hot Gas Valve does
not open.

Hot Gas Valve leaks
thru (warm tube
temperatures on both
sides of valve during
freeze)

Water Inlet Valve does
not open

Water Inlet Valve does
not flow enough water

Water Inlet Valve
leaks thru

Compressor does not
work

Open motor windings, or
seized bearings

No power to fan motor Contactor may not close.

Open motor windings, or
seized bearings

No power to pump Check electrical connections. In Freeze, the

Open solenoid coil. Replace hot gas valve

Stuck valve Replace hot gas valve

No power to coil in Harvest Check wire connections, if ok, replace AutoIQ

Mechanical problem in
valve

Open solenoid coil Replace valve

Stuck valve Replace valve

No power to valve (best
checked at the beginning
of Freeze)

Restriction in water supply Check water filters and/or inlet screen.

Mechanical problem in
valve

Unit in Clean cycle Push and release Freeze button.

Contactor coil open Replace contactor

Open starting components Check and replace

Open windings Check and replace compressor

Internal valve failure Replace compressor

Replace fan motor

Replace pump

pump should have power to it. If not, replace
the AutoIQ Controller.

Controller

Replace valve

Check wire connections, if ok, replace AutoIQ
Controller

Replace valve

CME456R

December 2000

Page 29

CME456R

Service Diagnosis

Problem or Symptom Possible Cause Probable Correction

Poor Harvest Scale in water system. Clean water system.

Water or Air Temperatures too
cold

Low system charge Recover and weigh charge.

Bypass solenoid does not open Check solenoid operation

Check valve leaks back Replace check valve

Hot gas valve does not open Check for power to the coil, if

Head pressure control valve
does not maintain enough
pressure (in freeze)

Low capacity High discharge pressure, from a

dirty condenser or faulty fan
motor

Extreme hot location Relocate the cabinet

Extremely hot condenser
location

Overcharge of refrigerant Recover, evacuate and weigh in

Hot gas valve leaks thru, unit off
on refrigeration error

Liquid and discharge lines are
in contact with each other

Compressor cycles on and off Compressor overheats Low on refrigerant, locate leak,

Check temps. Unit cannot
operate with water and air
temps below stated limits.

there is power, replace the hot
gas valve

Replace the head pressure
control valve

Clean the condenser, repair the
fan motor

Move condenser or provide
shade

the nameplate charge

At the end of the freeze cycle,
there should be a definite
difference in temperature
between the inlet and outlet of
the Hot Gas Valve. If not,
replace the hot gas valve

Separate and insulate them

recover refrigerant, repair leak,
replace drier, evacuate and
weigh in the nameplate charge.

TXV superheat too high, check
charge, if charge is OK, replace
TXV

Mechanical fault with
compressor, replace
compressor

Internal relief valve opened,
check for cause of high
discharge pressure

December 2000

Page 30

Operational Characteristics: CME456R

Cycle Times:

CME456R

70oF. condenser air 70oF. indoor

o

air, 50

Freeze 15 to 17 minutes 17 to 19 minutes

Harvest 3 ½ minutes 2 minutes

F. water

o

F. condenser air 90oF. indoor

90

o

air, 70

F. water

System Pressures (PSIG) (minutes):

70oF. condenser air 70oF. indoor

o

air, 55

Suction: End of Freeze 30 to 36 PSIG 34 to 38 PSIG

Suction: Peak in Harvest 75 to 85 PSIG 80 to 90 PSIG

Discharge: 5 minutes into Freeze 225 to 235 PSIG 230 to 240 PSIG

F. water

o

F. condenser air 90oF. indoor

90

o

air, 70

F. water

Number of Evaporators:

2

•

Refrigerant Charge

• 192 ounces of R-404A

Typical Compressor Amps,

•

7-13

Typical Harvest Ice Weight

•

5-7

Superheat

•

5 to 15 degrees

Hi Pressure Control - Automatic Reset

•

Hi Pressure Cut Out - 450 PSIG

•

Hi Pressure Cut In - 350 PSIG

Headmaster Valve

•

Setting is 217 PSIG

December 2000

Page 31

CME456R

Removal and Replacement

Inlet Water Valve

1. Remove the front and left side panels.

2. Shut off the water supply.

3. Push and release the OFF button.

4. Pull the wire harness off the inlet water valve.

5. Remove screws holding the inlet water valve to
the back panel.

6. Pull the valve away from the cabinet and
disconnect the outlet tube.

7. Unscrew the water valve from the water inlet
tubing. Hold the barbed inlet fitting and rotate the
valve.

8. Reverse to reassemble.

9. Push and release the Freeze button.

10. Replace the front panel.

Water Pump

1. Disconnect the electrical power.

5. Pull the inlet and outlet hoses off the purge
valve and remove it from the machine.

6. Reverse to reassemble. There are no internal
parts available for this valve.

Purge Valve Timer

The purge valve timer is sensitive to electrostatic
discharge. Be certain to touch a grounded surface
before touching this component. Do the same
when handling the replacement part.

1. Touch a grounded surface.

2. Remove front panel.

3. Disconnect electrical power.

4. Remove high voltage box cover.

5. Locate timer board at the bottom of the high
voltage box.

6. Unplug all the wires to the board.

7. Compress each of the four stand-off posts to
release the board from the stand-offs.

2. Remove the front panel.

3. Unplug water pump from its electrical
connection.

4. Remove 1 plastic bolt and the reservoir cover.

5. Lift water pump up and disconnect outlet tube.

6. Pull float ball from float stem (it is a snap fit).
Pull stem out.

7. Locate water level sensor mounting tabs,
compress together to release sensor from bracket.

8. Remove water pump brackets from pump.

9. Reverse to replace.

10. Replace front panel.

11. Re-connect electrical power.

Purge Valve

1. Disconnect electrical power.

2. Remove front panel.

8. Remove the board from the unit.

Reverse to reassemble.

Transformer and Compressor Starting
Components

Single phase compressors use a PTCR and run
capacitor. All are located in a sheet metal box to
the right of the AutoIQ Controller. The compressor
contactor is also located in that box.

1. Disconnect electrical power.

2. Remove front panel.

3. Remove 2 screws at the front edge of the metal
box, and pull the cover forward and out.

4. To check components, reconnect electrical
power.

Note: The contactor coil is 24 volt.

3. Unplug wire harness from purge valve coil.

4. Locate and remove the two screws securing the
purge valve to the machine.

December 2000

Page 32

Removal and Replacement: AutoIQ Controller

1. Disconnect the electrical power.

2. Remove the front panel.

3. Remove mounting screw holding controller to
cabinet.

4. Touch a metal surface to discharge any static
electricity.

5. Pull controller out slightly and unplug all
electrical connections.

Note: Do NOT touch the back of the controller.

6. Carefully remove the new controller from its
packaging. Again, do NOT touch the back of the
controller.

7. Plug all electrical connectors into the new
controller.

8. Re-attach the controller to the cabinet.

CME456R

9. Switch on the electrical power. All Lights should
lite up.

10. Push and release the Freeze button.

11. Replace the front panel.

Electric Eyes (Ice Sensors)

These must be replaced as a set.

1. Remove front panel.

2. Push and release the Off button.

3. Remove evaporator cover.

4. Remove cascading shield.

5. Locate the front and back ice sensors. Each has
a rectangular tab that was holding the cascading
shield. Pull on that tab until each sensor has been
removed.

6. Unplug sensors from controller connections 3
and 4.

7. Remove sensors from machine. Note: Some
cable ties may have to be cut and side panels
removed.

8. Reverse to reassemble. Be sure that the color
codes of the connecting wires match.

December 2000

Page 33

CME456R

Removal and Replacement: Water Level Sensor

Water Temperature Sensor

Note: This sensor is replaced as a set with the
Discharge Temperature Sensor.

1. Remove left side and front panel.

Electrical Shock Hazard

Disconnect Electrical
Power Before Beginning

1. Remove front panel.

2. Push and hold the OFF button. Release it when
the machine stops.

3. Trace wire harness from water level sensor to
the Controller (#2). Unplug the harness from the
controller.

4. Lift the pump and mounting plate up enough to
remove the float from the stem.

5. Remove two screws holding the sensor to the
pump bracket and lift the sensor up and out of the
machine.

6. Reverse to reassemble.

Discharge Line Temperature Sensor

1. Remove front panel, push and release the Off
button.

2. Push and release Off button.

3. Remove 1 plastic bolt and the reservoir cover.

4. Locate water temperature sensor (inserted into
pump discharge hose).

5. Pull out to remove.

6. Trace back to AutoIQ Controller, unplug from
#5.

7. Remove the Discharge Line temperature
sensor.

8. Reverse to reassemble.

Note: Do not push sensor tip in too far. There
should be about an 1/8" gap between the tip and
the inner wall of the water discharge hose.

2. Remove top and left side panels.

3. Locate discharge line sensor. It is attached to
the discharge line of the compressor, 6" from the
compressor discharge port.

4. Un-snap the clip holding the sensor to the
discharge line.

5. Trace the sensor wires back to the controller,
they are plugged into #5 with the water
temperature sensor, and must be replaced with it.

6. Reverse to replace, be sure that the discharge
line sensor is 6" up from the compressor discharge
port. The discharge line sensor is marked with
yellow tape.

Note: Route wires so they do NOT contact the
discharge line.

December 2000

Page 34

Refrigerant

CME456R

1. This ice machine uses R-404A or HP62 as a
refrigerant. It has several unique characteristics.

A. It is a near-azeotrope, and must be liquid
charged.

B. It must use polyol ester refrigerant oil, and that
oil is very water absorbent. The system must not
be open for more than 15 minutes.

C. An electronic leak detector capable of locating
HFC-134a type refrigerant must be used to locate
refrigerant leaks.

D. A special HFC type liquid line dryer must be
used.

E. When brazing, a dry nitrogen purge is required.

F. When evacuating, use of an electronic micron
gage is recommend. Evacuate to 300 microns.

Recovering the Refrigerant

Because of the check valves, liquid refrigerant
must be recovered thru the liquid line valve and
the low side access valve.

1. Low Side: Remove the stem cap and insert a
3/16" allen wrench. Check that the valve is closed.

Liquid Line: Remove the stem cap. Use a
refrigeration wrench and check that the valve stem
is fully UP or OUT. If recovering, remove the
schrod core before opening the valve.

4. Be sure that the low side access valve is closed.

5. Open the discharge side manifold valve and
weigh in the name plate charge. After the charge is
weighed in re-check the scale.

Liquid Charging

6. If all of the refrigerant charge has not been
weighed into the discharge side, it must be
carefully added thru the low side. Close the
discharge service access valve.

7. With a sight glass or charge faster in the hose to
the low side port, start the ice machine.

8. Open the low side service access valve.

9. Crack open the low side manifold valve and
watch the scale and sight glass. Open and close
the low side manifold valve to flow liquid into the
manifold but flash off to vapor before it enters the
suction side of the refrigeration system.

10. After the scale = the correct charge, shut off
the valve on the refrigerant cylinder.

11. With the ice machine running and the
discharge access valve closed, open both manifold
valves to allow the refrigerant in the hoses to enter
the system.

12. Shut the suction service access valve.

13. Remove the refrigeration manifold gages.

2. Remove the port caps and attach refrigerant
manifold hoses.

3. Open the valves. Note: Open liquid line valve
half way to access both sides of the liquid line.

4. Recover the refrigerant using the normal
techniques for the recovery machine used.

Evacuation

Evacuate to 300 microns

Charging

1. Use an electronic scale to measure the charge.

2. Place a drum or cylinder of R-404A on the scale
in position to dispense liquid refrigerant.

3. A refrigeration manifold is assumed to be
attached to the service access valves. Attach the
charging hose to the cylinder of R-404A. Open the
cylinder’s valve and purge the hose to the
manifold.

December 2000

Page 35

14. Replace and tighten all caps.

CME456R

Before Calling for Service

Check the following:

1. Has the water supply to the ice machine or building been shut off? If yes, the
ice machine will automatically restart within 25 minutes after water begins to
flow to it.

2. Has power been shut off to the ice machine? If yes, the ice machine will
automatically restart when power is restored.

3. Did the remote condenser’s fan stop turning? If yes, the ice machine may
need to be manually reset.

4. Does the bin control have ice on it? If so, remove the ice and the machine
should start in a few minutes.

To Manually Reset the machine.

1. Remove the front panel.

2. Locate the AutoIQ Controller. If a red
diagnostic light is glowing, note which one
and its blink rate. Then push and release the
off button.

3. Push and release the Freeze button.

4. The machine should begin to operate. If
there is a lack of water it will soon shut off
again.

5. Return the front panel to its normal
position.

If the machine shuts down again, call for
service.

To Shut the Machine Off:

1. Remove the front panel.

89

7

PUSH BUTTON

6

5

4

3

2

1

CONTROL SWITCHES

INDICATOR LIGHTS:

BIN FULL

FREEZE

HARVEST

CLEAN

OFF

DIAGNOSTIC LIGHTS:

WATER

REFRIGERATION

2. Locate the AutoIQ Controller.

3. Push and hold the Off button for 3
seconds or until the machine stops.

December 2000

Page 36

Bulletin Number: PS-4-2002
Bulletin Date: February 2002

SERVICE BULLETIN

Subject: New Ice Sensors in CME1356, CME1656 and CME2006. New Ice
Sensors, new Water Level Sensors and new Controllers in CME306 and
CME456.

Ice Sensors: Scotsman has begun production of ice machines equipped with a new style of ice

sensor. The new sensor is interchangeable with the prior sensors, which are still in use on other
Scotsman modular cubers.

Controllers: Scotsman has also added the new blue controller (see PS-3-2002) to models CME306
and CME456.

Water Level Sensor: A new water level sensor is also being used on CME306 and CME456.
Service parts for the ice sensors and water level sensor have not changed.
Ice machines built prior to this change are not affected.
The new sensors’ use will be phased in by model throughout 2002.
Additional information is on the back of this bulletin.

Ice Sensor

Photo-Eyes in New Ice Sensor

Sensor Holder

Push to Release Photo-Eye

The new ice sensor’s have a photo-eye module that
can be separated from the holder.

Once separated, the lenses of the photo-eyes can
easily be cleaned with a soft cloth or cotton swab. Ice
machine cleaner may be used if needed.

Like the other style of sensor, the photo-eye part can
be placed in the reservoir when the ice machine is
being cleaned with ice machine cleaner.

When re-assembling, be sure that the wire is not
sticking out past the edges of the sensor holder.

Module

Photo-Eye Module Separated

from Holder

Route Wire Under Clip, Push

Module Into Place