Scotsman CME500 SERVICE MANUAL

Introduction

CME500

To the owner or user: This service manual is
intended to provide you, and the maintenance or
service technician, with the information needed to
install, start up, clean, maintain and repair this
product.

The CME500 is an ice machine that produces
cubed ice on 4 vertical cube freezing surfaces. The
ice falls as vertical strips of cubes into the ice
storage bin where they break up into individual
cubes. The CME500 automatically maintains the
level of ice by turning on when the ice level falls,
and switches off when the bin is full.

The refrigeration system uses HP62 as the
refrigerant. HP62 models use polyolester
refrigerant oil.

Information on HP62 is located on page 22.

Table of Contents

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2

Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 3

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4

Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 6

Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 7

Final Check List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 8

Component Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 9

Initial Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 10

Electrical Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 11

Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 12

Water/ Refrigeration Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 15

Technical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 17

Service Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 18

Removal and Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 20

Parts lists and wiring diagrams are located in the
center of this manual, printed on yellow paper.

Note the warning symbol where it appears in this
manual.

It is an alert for important safety information on a
hazard that might cause serious injury.

Keep this manual for future reference.
This manual was printed on recycled paper.

October 1994

Page 1

CME500

Specifications

Information regarding Model Number, Serial
Number, Ampacity and Maximum Fuse Size are
located on the nameplate of the ice machine. The
model number, serial number and refrigerant
charge are also listed on
the serial number plate
just behind the front
panel.

If recharging, always
use the charge listed on
the ice machine.

Nameplate

Serial Number

Plate

CME500 Cabinet

The CME500 will stack onto a variety of ice
storage bins, see sales literature for proper ice
storage bin. Examples of bins this machine will fit
are:

••*BH550

••*HTB500, HTB350, HTB250

••BH800 (with bin top KBT23)

••BH900 (with bin top KBT22)

••BH1360

It will also fit these Scotsman Dispensers:

••CD200

••IS150 (with KADCM1)

••RS150 (with KADCM1)

* These smaller bins are recommended.
There is an optional stainless steel panel kit,

SPKCMD-1, for this machine.

Specifications:

Model Number Dimensions

W" x D" x H"

CME500AE-1A 30 x 24 x 27 Air 115/60/1 19 20 32 ounces
CME500WE-1A 30 x 24 x 27 Water 115/60/1 19 20 20 ounces

Condenser
Type

Basic
Electrical

August 1994

Page 2

Minimum
Circuit
Ampacity

Maximum Fuse
Size (or HACR
circuit breakers)

Refrigerant
Charge. HP-62
(R-404a)

For The Installer: Environmental Limitations

The ice machine must be installed indoors in a
controlled environment.

Minimum Maximum

0

Air Temp 50
Water Temp 40
Water Pressure 20 PSI 80 PSI
Voltage 103.5 126.5
Operating the ice machine outside of the above

limitations, or outdoors, is potentially damaging to
the machine, and it is misuse of the machine. This
may void the warranty.

Scotsman Ice Systems are designed and
manufactured with the highest regard for safety
and performance. They meet or exceed the
standards of UL, NSF, and CSA.

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 part and/or other components not
specifically approved by Scotsman.

F. 1000F.

0

F. 1000F.

CME500

Scotsman reserves the right to make design
changes and/or improvements at any time.

Specifications and design are subject to change
without notice.

Airflow on air cooled models is:

••Intake through the right side grill.

••Exhaust through the left side grill.

Do not install where this air flow is obstructed. A
clearance of 6 inches is required at the back and
sides.

October 1994

Page 3

CME500

Installation

Water
The water supply for this ice machine has been in
contact with many materials since it fell from the
sky as rain. All rain is slightly acidic, and tends to
dissolve the materials it comes in contact with.
During water’s journey to the ice machine, it has
flowed over and through the ground, been picked
up by a municipal or private pump, forced through
a series of pipes of differing construction and may
have been treated by the municipality providing
the water.

The water supplied to this ice machine will then
contain a variety of substances that will likely show
up as solids during the ice making process. These
solids are similar to those found when water is
boiled out of a saucepan. Only the water boils
away, and the minerals that were in the water
solidify in the pan. During ice making only the
water is frozen into ice, the minerals stay behind in
the reservoir. This machine pumps out the water in
the reservoir every cycle to minimize the amount of
minerals in the water system, but after time the
minerals will appear and have to be dissolved by
ice machine cleaner, then flushed away during the
cleaning process.

Air cooled models blow air in and out through the
grills at the sides (in the right and out the left).
Space is required for air flow at the sides and utility
connections at the back.

The ice machine is not designed for outdoor
use. It must be installed indoors, in a
controlled environment. The air and water
temperatures must not exceed rated limits.

Pre-installation:

1. Inspect the place where the ice machine is to be
installed. Check for:

••space for the cabinet,

••water supply,

••drain availability

••and electrical power supply.

No extension cords are allowed. The building drain
inlet must be lower than the drain outlet of the ice
bin. The water supply must have a hand shut off
valve accessible when the unit is installed.

An ice machine is a food manufacturing plant; it
takes a raw material, in this case water, and
transforms it into a food product, ice. The purity of
the water is very important in obtaining pure ice
and in maximizing product life.

The water to the ice machine should be filtered.
Water filters vary greatly in ability and function.
Install one that filters out suspended solids to a
dimension of 5 microns or less. The finer the filter
the better, but finer filters may plug-up sooner than
course ones. It may be necessary to add a course
filter ahead of the fine filter to prolong filter life.

Have the water tested. Acidic water or alkaline
water will both cause corrosion. Dissolved solids
cannot be filtered out. Check with a water
treatment specialist regarding testing, treatment
and filters.

August 1994

Page 4

Reservoir

Bin Thermostat

Installation

Installation

Assembly:

1. Attach the legs, or optional casters, onto the ice
storage bin. Units that are stacked should only use
legs, not casters.

CME500

2. Place the ice machine onto the storage bin.

3. Line up the ice machine, check that there is a
good seal between the ice machine and the
storage bin.

4. If on a Scotsman bin, attach the ice machine to
the bin using the straps and bolts shipped with the
ice machine. If on another brand bin, follow the
directions included with that bin.

Bin Thermostat Installation:

1. Remove rubber cap from the end of the
thermostat bracket.

2. Attach the bin thermostat bracket to the bottom
of the ice machine using the thumb screws
provided. There are pre-drilled and tapped holes
located just behind the cube drop area. The end of
the bin thermostat bracket with the plastic tubing
on it will fit into the hole in the base of the machine.

3. Locate and uncoil a portion of the bin thermostat
capillary tube. Route the end of the capillary tube
into and through the bin thermostat bracket tube. It
should be inserted the full length of the tube, but
not past the end.

Thermostat

Capillary Tube

Bin Thermostat

Bracket

Stacking

Stacking:

This machine will stack onto any CM250,
CME250, CM450, CM500, CME500, CM650 or
CME650 with the same cabinet depth (24").

1. Remove and discard the top panel from the
lower unit.

2. Carefully lift the uncrated top unit onto the
bottom unit. Use of a mechanical lift is
recommended for this step.

3. Align the two ice maker cabinets.

4. Secure the top unit to the bottom one with the
hardware and straps shipped with the upper
machine.

5. Locate and uncoil all of the bin thermostat
capillary tube.

6. Route the bin thermostat capillary tube from the
upper unit, through the hole in the back of the
reservoir, through the lower unit and into the bin
thermostat bracket. Discard upper unit bracket.

Strap

Bin Thermostat Bracket

Capillary Tube

Routing Hole

October 1994

Page 5

CME500

Installation

For The Plumber

1. Connect cold potable water to the 3/8" male
flare at the back of the cabinet. A water filter is
recommended. Flush the water line prior to
connecting to the ice machine.

If water cooled, connect a separate water inlet line
to the water cooled condenser inlet fitting. It should
also have a hand shut off valve.

A loop of copper tubing may be used between the
ice machine and the water supply. This will allow
the ice machine to be pulled out from its installed
location without disconnecting the water line. No
back-flow preventer should be needed in the inlet
potable water line because provision for that is
incorporated in this N.S.F. listed product (the tube
from the inlet water valve has an air break in it, is
above the reservoir wall and cannot siphon).

2. Connect a drain tube to each drain. The drain
tubes from these connections must be run
separately. There are two connections, one is the
bin drain and the other is the reservoir drain. The
reservoir drain is a 3/4" F.P.T. brass fitting.

Drain tube material must be rigid and meet local
code.

Traps in the bin drain line without vents ahead of
them will cause poor draining.

The bin drain must be vented if there is a long
horizontal run (5’ or more). The reservoir drain
must be vented and not connected to the bin drain.
All drains are gravity, and must have a minimum
fall of 1/4" per foot of horizontal run. The water
cooled condenser drain is not vented, and is
routed separately.

Maintain the air gap required by local code
between the end of the drain tubes and the
building drain receptacle.

Note: Drain tubing should be insulated to prevent
condensation from forming on the tubing.

CONFORM TO ALL LOCAL CODES

3/8 Male Flare

Water Inlet

Water Shut

Off Valve

Reservoir Drain

3/4" FPT, Must Be Vented.

Bin Drain. May Be Routed From

The Bottom On Some Model

Bins. Fitting May Be Plastic.

DO NOT OVERHEAT.

3/8" FPT Inlet

1/2" FPT

Outlet

Water Cooled

Condenser Plumbing

Connections

Ice Storage Bin

(Typical)

Water Supply and Drain Connections

August 1994

Page 6

Installation

For The Electrician

This unit must be on a separate 115 volt AC 60
cycle single phase power supply. The maximum
fuse size for this circuit is listed on the nameplate,
and per the nameplate use fuses, or HACR circuit
breakers.

Electrical connections are made at the rear of the
ice maker, inside the junction box.

Recommendation: If using wire nuts, cut off the
"tinned" ends of the wires and strip off 1/2" of
insulation from the end of the wires so there is a
copper to copper connection.

Follow All Local Codes - This Unit Must Be
Grounded

required to connect the electrical service.

. Usually a licensed electrician will be

CME500

Junction Box

Hand Disconnect Switch

October 1994

Page 7

CME500

After Utility Connections

1. Level the cabinet, use the leg levelers on the
end of the legs to adjust the cabinet height. (Legs
should have been installed when the bin was
unpacked).

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

Final Check List

1. Is the ice maker cabinet in a room where
ambient temperatures are within the minimum and
maximum temperatures specified?

2. Has the water supply been connected?

3. Is the water pressure adequate?

4. Have the water connections been checked for
water leaks?

5. Have the drain connections been made?

6. Have the drain connections been checked for
leaks?

7. Is the cabinet level?

8. Is the ice machine connected to a 115 volt
electrical power supply and is the ice machine the
only load on that circuit?

9. Has all of the shipping material been removed
from the inside of the cabinet?

10. Has the bin thermostat bracket been attached
to the bottom of the ice machine, and the capillary
tube routed thru the bracket?

11. Has the bin and cabinet been wiped clean and
sanitized?

12. Has the Customer Evaluation & Warranty
Registration form been properly filled out? Check
for correct model and serial numbers from the
nameplate, then mail the completed form to
Scotsman.

13. Has the owner/user been given the name and
telephone number of the authorized Scotsman
Service Agency serving that location?

August 1994

Page 8

Component Location

Bin Thermostat Bracket

Overflow

Standpipe

The ice machine is designed for front service.
Many components are serviceable from the front
without removing the side panels.

Behind the front panel:

•• Water pump

•• Inlet water valve

•• Reservoir

•• Evaporators

•• Water distributor

•• Control box with cube size control adjustment

•• ON/OFF switch

•• Compressor switch

Inside the control box is control system for the ice
machine.

CME500

Timer

Cube Size Control

Master Switch

Control Box

Bin Thermostat

Compressor Switch

Bin Thermostat

Water

Distributors

Drain Trough

Component Location

Water Pump

Water Inlet Valve

October 1994

Page 9

Freeze

Cam Follower

CME500

Initial Start Up

After the final check list has been gone through,
the ice machine may be started up.

1. Open the water shut off valve.

Timer

2. Switch on the electrical power.

2. Remove the front panel.

4. Remove the control box cover.

5. Locate the timer and

Control Box

rotate the cam clockwise
until the timer is in the
Harvest Position.

6. Switch the compressor
switch to OFF.

3. Locate the ON/OFF
switch, switch it to ON.

4. The inlet water valve will
open, and water will flow
into the reservoir. The
water pump will begin to
pump water over the
evaporators.

5. Allow the reservoir to fill.

6. Switch the compressor
switch to ON.

Cam

Timer Shown In Harvest Position

Harvest

Cube Size

Control Knob

Cubes Too

Thick

Bin

Thermostat

7. On air cooled models the fan motor will begin to
turn, and warm air will be discharged from the left
side of the ice machine. On water cooled models
warm water will begin to flow from the condenser
drain.

Note: To optimize the balance between ice
production and water use, the water cooled
discharge pressure must be 245 P.S.I.G. Check
discharge pressure and adjust water regulating
valve to obtain 245 P.S.I.G. discharge pressure.

8. The water temperature in the reservoir will soon

0

be 32

F., and ice should begin to form on the
evaporators. Note: In some cases some slush will
form in the reservoir. This is temporary and normal.

9. Allow the ice machine to operate for about 22
minutes. The ice should be fully formed and should
be harvested within a few minutes.

10. After harvest, check the ice cube size. If
needed, adjust the cube size by rotating the
adjustment knob of the cube size control. Rotate it
1/8 turn clockwise to make the cubes thicker, and
rotate it 1/8 turn counterclockwise to make the
cubes thinner.

The machine is designed to only harvest

cubes that are the correct thickness.

Correct Size & Shape

At this size, the typical batch

weight will be 5.5 lb. per cycle.

Cubes Too

Thin

August 1994

Page 10

Initial Start Up

CME500

11. Check harvest time. The machine will have
to harvest all of the cubes before it goes back
into the freeze cycle.

Cam Follower

Cam

Timer Shown In Harvest Position

Freeze

Increase the Harvest Time if there is less than 15
seconds of harvest time after the last cube has
fallen into the bin. The machine ships set at 2
minutes of harvest time.

Decrease the Harvest Time if there is much more
than 15 seconds of harvest time after the last cube
has fallen into the bin. Note: Harvest time is
dependent upon the water and air temperatures at
the ice machine. Colder air and water will result in
faster ice making, but longer harvest cycles. Do
NOT adjust harvest time too short, as this will case
a freeze up of the evaporators.

Timer

Harvest

2

⁄

3

Electrical Sequence:

This describes the sequence through a complete
cycle.
Freeze Cycle:
During the first part of the freeze cycle, the ice
machine compressor, fan motor if air cooled, and
water pump are operating. The relay in the middle
of the circuit board is energized.
Timed Freeze:
Cube size control closes, connecting power to the
timer motor, and after a few (4.5-5.5) minutes this
timer opens the circuit to the relay on the circuit
board. This starts the harvest cycle.
Harvest:
In the harvest cycle, the water pump and
compressor stay operating, and these two valves
are energized:

•• Hot gas valve

•• Inlet water valve

The unit stays in the harvest cycle until the timer
has turned the cam which has pushed the timer
micro switch button IN. If the bin thermostat is
OPEN, the ice machine will stop. If the bin
thermostat is CLOSED, the relay will energize, and
the unit will make another batch of cubes.

To Adjust Harvest Time:

1. Disconnect electrical power.

2. Locate time cam in control box.

3. Loose set screw holding the two halves of the
cam together, and rotate the front half to increase
or decrease the harvest portion of the cam (low
part).

4. Re tighten the set screw.

5. Reconnect power and check cube size of the
next cycle, as it may require adjustment after the
harvest time has been set.

12. Check operation of the bin control circuit by
holding ice on the bin control tube in the bin. This
simulates bin full and the ice machine should
switch itself off at the end of a harvest cycle.

13. Replace all the panels. The ice machine is now
ready for automatic operation..

October 1994

Page 11

CME500

Maintenance and Cleaning

Cleaning Schedule:

••Scrub the outside of the cabinet once a week

with soap and water.

••Wash off the bin door, frame and gaskets daily.

••Sanitize the bin interior once a month.

••Clean the water system and air cooled

condenser a minimum of twice per year. If in an
area of high mineral concentration in the water
supply, clean water system 4 times a year.

This ice machine will perform at its best when kept
clean. There are two areas to keep clean: The
water system including the water reservoir,
distributor tube and evaporator surface; and the
air cooled condenser filter and the condenser itself.

Inlet Water Valve Screens

If a restriction of incoming water is suspected, the
screen on the inlet side of the water valve should
be inspected & cleaned. Some models also have a
strainer in the water line; the strainer screen
should also be inspected for restricting minerals.

Inlet Water Valve

Air Filter (air cooled only):

1. Remove the grill on the right side of the unit.

2. Remove the filter pad from in front of the
condenser.

3. Wash the surface of the filter off with cold water,
or, if torn or so dirty it can’t be cleaned, replace
with a new filter.

4. Return the filter to its installed position.

5. Replace the grill. Do not operate the unit without
the filter in place.

Note: If the unit has been operated without the
filter in place, the fins of the condenser will
become fouled with dirt, and must be cleaned. A
vacuum cleaner with a soft brush attachment will
extract most loose dust stuck to the surface of the
condenser fins. If there is any doubt about dirt
inside the fins of the condenser, the cabinet should
be removed and a qualified service agent should
clean the condenser.

Water cooled units:

The water cooled condenser may, over time and
under certain water conditions, become internally
restricted by minerals. These will have to be
dissolved by acid or the condenser replaced. Only
a qualified service agent should attempt this type
of service.

Inlet Screen

August 1994

Page 12

Cleaning: Ice Storage Bin

CME500

The interior liner of the bin is in contact with a food
product: ice. The storage bin must be cleaned
regularly to maintain a sanitary environment.

Every 30 days, the liner should be sanitized with a
commercial ice machine sanitizer, according to the
directions of the sanitizer, or with a solution of
household bleach and water:

1. Mix the bleach and water using the ratio of one
ounce of bleach to two gallons of water.

2. Wipe all interior surfaces of the ice storage bin
with the bleach and water.

3. Allow to air dry.
Note: If the ice baffle was removed from the bin

during cleaning it must be reinstalled in the bin.

To Remove Scale:

1. Mix a cleaning solution of 4 ounces of Scotsman
Ice Machine Cleaner to 4 pints of hot

0

(95

F.-1100F.) water.

2. Using rubber gloves, dip a nylon scouring pad
into the cleaning solution and scrub the scale off
the liner.

Stainless Steel Components Inside Bin

The stainless steel parts in the bin also require
periodic cleaning. Chemicals in the water supply,
such as chlorine, cause brown stains to appear on
the surface of the stainless steel parts.

1. General Cleaning - staining is usually removed
by washing the parts with ordinary cleaning
powder such as Bon-Ami or Copper-Glo and
water. After cleaning, rinse with clear water.

2. Water treatment. The chlorine enters the
machine from the municipal water supply. It can be
removed from the water supply by using a
charcoal or activated carbon water filter to treat the
water to the ice machine. If staining is severe,
filters of this type are recommended.

Exterior Cabinet Cleaning:

The exterior cabinet may be cleaned by scrubbing
with soap and water. Do not use cleaners
containing petroleum products.

A nylon type brush may be used to scrub stubborn
deposits.

3. After the scale has been removed, rinse all
surfaces inside the bin with clean, potable water.

October 1994

Page 13

Water

Distributor

Removal of Water Distributor

CME500

Cleaning: Ice maker

1. Remove front panel.

2. Remove control box cover, and turn the timer
cam clockwise until the unit is in a harvest cycle. At
the end of the harvest cycle switch the master and
compressor switches to OFF. Replace the control
box cover.

3. Remove all ice from the bin.

4. Remove 4 thumbscrews and the evaporator
cover.

5. Remove water pump discharge hose from
evaporator water inlet, direct hose into bin or
bucket and switch the master switch ON until
reservoir is empty of water. Replace hose on inlet.

6. Replace evaporator cover.

Scotsman Ice Machine
Cleaner contains acids.
These compounds may
cause burns.

If swallowed, DO NOT
induce vomiting. Give
large amounts of water or
milk. Call Physician
immediately. In case of
external contact, flush
with water.

KEEP OUT OF THE
REACH OF CHILDREN.

15. Switch master and compressor switches ON.

16. Replace the front panel

17. Discard the next batch of cubes to make sure
all of the acid & sanitizer is gone.

/////////////////////////////////CAUTION///////////////////////////////
DO NOT use ice cubes produced from the

cleaning or sanitizing solutions. Be sure none
remain in the bin.

/////////////////////////////////////////////////////////////////////////////////

18. Pour hot water into the storage bin to melt the
cubes and also clean out the bin drain.

19. Wash the bin liner with a solution of household
bleach (1 ounce of bleach to 2 gallons of water)
and warm (95

o

F. - 115oF.)water. Allow to air dry.

20. The unit will now continue automatic operation.

Water Distributor:

Note: The water distributor may need to be
cleaned separately.

1. Remove evaporator cover.

2. Remove water distributor assembly by pushing
the assembly to the right until the left end clears
the retaining tab.

7. Mix 8 ounces of Scotsman Ice Machine Cleaner
with 1 gallon of warm (95

0

F. - 1150F.) water and

pour into the reservoir until full.

8. Switch the master switch ON, and operate the
unit for 20 minutes, then switch the unit OFF.

9 Repeat steps 4 and 5.

10. Wash the plastic and stainless liners of the
freezer section with a solution of household bleach
(1 ounce of bleach to 2 gallons of water) and warm

o

(95

F. - 115oF.) water. Allow to air dry.

1

11. Pour

⁄2 gallon of the solution mixed in step 10

into the reservoir. Replace the evaporator cover.

12. Switch the master switch back ON, operate the
unit for 5 minutes. Switch unit OFF.

13. Repeat steps 4, 5 and 6.

14. Pour about 1/2 gallon of clean potable water
into the reservoir, and switch the master switch
ON. After 5 minutes switch the master switch OFF
and repeat steps 4, 5 and 6.

Retaining

Tab

3. Lift up the left end of the water distributor
assembly and pull the assembly to the left.

4. Un-snap the water distributors from the "T", and
inspect for mineral deposits. Clean as required.

5. Reverse above steps to reassemble. Be certain
that water distributors are in place and secure.

Scale that may form on the plastic liner can be
removed by scrubbing the surface with a mixture
of Scotsman Ice Machine Cleaner and hot water.
Remove any scale prior to cleaning.

August 1994

Page 14

Refrigeration Schematic:

Hot Gas Valve

Suction Line

Compressor

CME500

Freeze Cycle:

From the compressor, hot discharge gas is
pumped to the condenser, either air or water
cooled.

At the condenser, heat from the refrigerant flows
into the cooling medium, either air or water, and
the refrigerant condenses into a liquid. From the
condenser the liquid refrigerant flows through the
liquid line to the metering device - a thermostatic
expansion valve.

At the expansion valve, liquid refrigerant passes
from a high pressure zone to one of relatively low
pressure, and in the low pressure zone it
evaporates. The low pressure zone where the
refrigerant evaporates is the evaporator. When the
refrigerant evaporates, it absorbs heat from the
metal parts of the evaporator and the water flowing
over it.

From the evaporator, the refrigerant flows back to
the compressor through the suction line.

Water Schematic:
Water flows into the ice machine from its inlet

connection at the back of the cabinet, through the
inlet water valve and into the reservoir. The water
in the reservoir is pumped up and through the
water distributor tube at the top of the evaporators.
From there, the water flows over both sides of the
evaporators and back into the reservoir.

Evaporator

Water
Pump

Inlet

Water

Valve

Water Reservoir

Water Distribution

System

Thermo Exp.

Discharge Line

Refrigeration Schematic

Liquid Line

Condenser

Fan Motor

Valve

Dryer

October 1994

Page 15

Hot Gas Valve

(OPEN)

Suction Line

Compressor

Hot Gas

Valve
Filter

CME500

Harvest Cycle:

During the harvest cycle, the refrigerant flows from
the compressor, through the discharge line to a
branch in the line containing the Hot Gas Valve.
This valve is Open during the harvest cycle,
allowing the hot discharge gas to bypass the
condenser and enter the evaporator at its inlet.

The hot discharge gases warm up the evaporator
enough to allow the surface of the ice frozen to the
evaporator to melt. The remaining ice will then fall
off into the bin.

During the Harvest Cycle, the inlet water valve
opens, filling the reservoir and allowing the
reservoir to overflow the drain.

Evaporator

Water
Pump

Inlet

Water

Valve

(OPEN)

Water Reservoir

Water Distribution

System

Thermo. Exp.

Discharge Line

Refrigeration Schematic

Liquid Line

Condenser

Fan Motor

Valve

Dryer

August 1994

Page 16

Technical Characteristics

Typical Cycle Time

•• 24 minutes @ 90

•• 19 minutes @ 70

Typical Harvest Ice Weight

•• 5.5 - 6 pounds.

Typical Low Side Pressure Just Before Harvest

•• Air cooled = 40 PSIG; Water cooled = 35 PSIG

Typical Freeze Cycle Air Cooled Discharge Pressure

•• 275 - 290 PSIG @ 90

Refrigerant Charge:

•• Air cooled = 32 ounces R-404A

•• Water cooled = 20 ounces R-404A

Harvest Time

•• Pre-set at 2 and

Typical Low Side Pressure, in harvest:

•• Air cooled = 105 PSIG; Water cooled = 85 PSIG

o

F. air and 70oF. water

o

F. air and 50oF. water

o

F. air and 70oF. water

2

⁄3 minutes. Adjustable to match field requirements.

CME500

Typical Peak Discharge Pressure, in harvest:

•• 200-210 PSIG

Hi Pressure Cut Out Point:

•• 450 PSIG, air cooled; 400 PSIG, water cooled

Fan Pressure Switch

•• 240 PSIG C.I.

•• 190 PSIG C.O.

Hi Temperature Cut Out Point:

o

•• 140

Typical Compressor Amp Draw:

F. (at hot gas valve)

•• 10-12 during the freeze cycle and 12-15 during the harvest cycle (115 v).

Compressor:

•• Copeland: RS55C1E-PAA-213

Water Inlet Valve Flow Rate:

••

.75 g.p.m.

Cube Size Thermostat:

•• Adjustable Cut In as needed to obtain correct cube size, C.I. range between 42

o

F. and 5oF

Bin Thermostat

•• Adjustable; C.I. range between 38.5

Thermostatic Expansion Valve

••Not adjustable

o

F. and 43.5oF, C.O. range between 33.5 oF. and 38.5 oF

October 1994

Page 17

CME500

Service Diagnosis:

SYMPTOM POSSIBLE CAUSE PROBABLE FIX

No ice is made, nothing operates Unit off, due to no power Restore power

Unit off, due to master switch in
OFF position

Unit off, due to bin thermostat
open

Unit off, due to hi pressure cut out
open

Unit off, due to hi temperature cut
out open

Unit off, due to circuit board open Check for short circuit and

No ice is made No water due to water turned off. Reconnect water supply

No water due to water filter
plugged.

No water due to inlet water valve
screen plugged

No water due to strainer screen
plugged

No water due to Inlet water valve
coil open

No water due to inlet water valve
will not open

Water in reservoir, but no water
over evaporators

No cooling at evaporator due to
compressor switched off

No cooling at evaporator due to
too much heat load because inlet
water valve leaks thru

No cooling at evaporator due to
hot gas valve leaking thru

No cooling at evaporator due to
fan not turning

No cooling at evaporator due to
dirty condenser

Switch master switch to ON

Check temperature at bin
thermostat bracket, if warmer
than 40
closed. Adjust/replace thermostat.

Reset and check for dirty
condenser, hot location, or water
interruption (if water cooled).

Hot gas valve leaking thru,
replace hot gas valve.

replace circuit board.

Replace water filter

Clean out inlet screen

Clean out inlet screen

Replace valve

Replace valve

Water pump does not work,
replace pump

Switch compressor on.

Replace inlet water valve

Replace hot gas valve

Check & replace fan motor or fan
control switch

Clean condenser

o

F., thermostat should be

August 1994

Page 18

CME500

Service Diagnosis

SYMPTOM POSSIBLE CAUSE PROBABLE FIX
No ice is made No cooling due to low refrigerant

charge

Will not harvest due to hot gas
valve not opening.

No cooling due to compressor not
operating

Will not harvest due to not
enough harvest time.

Will not harvest due to lack of
water.

Makes ice, but very little High discharge pressure, due to

dirty condenser, faulty fan motor,
fan pressure switch, not enough
water thru water cooled
condenser.

Inlet water temperatures and
room ambient very high

Compressor inefficient Check/replace compressor

Cubes are wrong size/shape Cube size control not adjusted

properly
Water system is restricted with

minerals
Not enough water Check water supply pressure

Ice fused together in bin Ice in bin too long Advise user to pour water on ice

Too many minerals in water Suggest water treatment to user.

Water drips on ice Water distributors loose Set water distributors in place on

Some water is normal. Advise user.
Cube size too small Adjust thicker.
Water system is dirty Clean water system with ice

Locate leak, recover remaining
refrigerant, replace dryer,
evacuate and weigh in nameplate
charge.

Check for voltage to coil in
harvest, if there is voltage check
coil, if coil is ok, replace hot gas
valve

Check compressor for voltage,
continuity, and operation.
Replace if found to be faulty.

Adjust harvest time longer.

Check water supply & distribution
system. Clean water system with
Scotsman Ice Machine Cleaner.

Check for causes of high
discharge pressure and correct.

Advise user, suggest additional
room cooling.

Adjust cube size control

Clean water system with
Scotsman Ice Machine Cleaner

Check water supply for restrictions

to ease removal

top of evaporator.

machine cleaner.

October 1994

Page 19

Replacement of Cube Size

CME500

Removal and Replacement

Cube Size Control:

Before replacing the cube size control, it should be
positively determined that it is at fault.

If it does not open when warm, replace it.

1. Disconnect electrical power.

Electrical shock hazard.

Electrical shock can
cause personal injury.

Disconnect power before
beginning to service
components.

2. Remove the front panel.

3. Remove the control box cover.

4. Locate the cube size control.

5. Remove the two screws holding the control to
the control box, and lift the control out.

6. Pull the two wires off the posts of the cube size
control.

7. Follow the capillary tube of the cube size control
and remove it from the grommet in the back of the
control box.

Suction Line

Cube Size Pig-Tail

Socket

8. Locate bulb on suction line.

9. The end of the cube size control is inserted in a
socket attached to the suction line. Pull it out of the
socket.

10. Replace the cube size control with the proper
part number, following the above steps from 9-1.

August 1994

Page 20

Removal and Replacement

CME500

Water Pump

The pump provides the force to move the water
from the reservoir to the freezing surface. The
pump does not need oil, but if it becomes noisy,
overheats, or will not pump it should be replaced.
Be certain to confirm electrical faults with a
voltmeter or ohmmeter before replacing the pump.
The pump should be operating whenever the
compressor is.

1. Unplug or disconnect the electrical power.

Electrical shock hazard.

Electrical shock can
cause personal injury.

Disconnect power before
beginning to service
components.

2. Unplug the pump from its connection.

Inlet Water Valve

The valve water to enter the reservoir during
harvest but not during freeze. The valve may
plug-up from minerals in the water, and may be
cleaned rather than replaced.

1. Shut off the water supply.

2. Unscrew the fitting at the back of the valve, and
pull the water inlet tube out of the valve body.

3. Remove the screws holding the valve to the
bracket.

4. Unplug the electrical connection from the valve.

5. Remove the valve from the ice machine.

6. Reverse the above steps to reassemble.

3. Loosen the two fasteners holding the bracket to
the wall.

4. Pull discharge hose from pump discharge port.

Replacement of Water

Pump

5. Remove pump from ice machine.

6. Remove bracket from pump.

7. Reverse above steps to replace.

Inlet Water Valve

October 1994

Page 21

CME500

REFRIGERATION SYSTEM: HP62 (R-404A) Refrigerant

THIS ICE MACHINE USES HP62 REFRIGERANT
AND POLYOLESTER COMPRESSOR OIL

DO NOT USE MINERAL OIL IN THIS
REFRIGERATION SYSTEM.

••HP62 is a "Near Azeotrope", and therefore

liquid charging is required.

¤ Weigh in as much of the charge (as liquid) as

possible into the discharge size.

¤ Install a sight glass between the suction side

and the gage manifold. Use the manifold
valve to "flash off" the liquid refrigerant before
it enters the ice machine. Do this until the
proper charge is weighed into the system.

••When the system is serviced, a special liquid

line dryer is required (see parts list).

••Polyolester oil absorbs water very easily, and

therefore when the system is opened for
service, it must be re-sealed as soon as
possible (15 minutes maximum).

••Special leak detection equipment is required to

locate small refrigerant leaks. Usually a leak
detector capable of detecting a Halogenated
refrigerant or HFC-134a will work. Check with
the leak detector manufacturer if in doubt.

••Do NOT mix with air for leak testing.

Pressure-Temperature Chart for HP62

VAPOR VAPOR
TEMP. PRESSURE TEMP. PRESSURE
(DEG F) (PSIG) (DEG F) (PSIG)

-20 . . . . . . 17 70 . . . . . . . 146

-18 . . . . . . 18 72 . . . . . . . 150

-16 . . . . . . 20 74 . . . . . . . 155

-14 . . . . . . 21 76 . . . . . . . 161

-12 . . . . . . 23 78 . . . . . . . 166

-10 . . . . . . 24 80 . . . . . . . 171

-8 . . . . . . . 26 82 . . . . . . . 177

-6 . . . . . . . 28 84 . . . . . . . 182

-4 . . . . . . . 29 86 . . . . . . . 188

-2 . . . . . . . 31 88 . . . . . . . 194

0 . . . . . . . 33 90 . . . . . . . 200

2 . . . . . . . 35 92 . . . . . . . 206

4 . . . . . . . 37 94 . . . . . . . 212

6 . . . . . . . 39 96 . . . . . . . 219

8 . . . . . . . 41 98 . . . . . . . 225

10 . . . . . . . 43 100 . . . . . . 232

12 . . . . . . . 46 102 . . . . . . 239

14 . . . . . . . 48 104 . . . . . . 246

16 . . . . . . . 50 106 . . . . . . 253

18 . . . . . . . 53 108 . . . . . . 260

20 . . . . . . . 55 110 . . . . . . 268

22 . . . . . . . 58 112 . . . . . . 275

24 . . . . . . . 60 114 . . . . . . 283

26 . . . . . . . 63 116 . . . . . . 291

28 . . . . . . . 66 118 . . . . . . 299

30 . . . . . . . 69 120 . . . . . . 307

32 . . . . . . . 72 122 . . . . . . 316

34 . . . . . . . 75 124 . . . . . . 324

36 . . . . . . . 78 126 . . . . . . 333

38 . . . . . . . 81 128 . . . . . . 342

40 . . . . . . . 85 130 . . . . . . 351

42 . . . . . . . 88 132 . . . . . . 360

44 . . . . . . . 91 134 . . . . . . 370

46 . . . . . . . 95 136 . . . . . . 379

48 . . . . . . . 99 138 . . . . . . 389

50 . . . . . . . 102 140 . . . . . . 399

52 . . . . . . . 106 142 . . . . . . 409

54 . . . . . . . 110 144 . . . . . . 420

56 . . . . . . . 114 146 . . . . . . 430

58 . . . . . . . 118 148 . . . . . . 441

60 . . . . . . . 123 150 . . . . . . 452

62 . . . . . . . 127 152 . . . . . . 464

64 . . . . . . . 132 154 . . . . . . 475

66 . . . . . . . 136 156 . . . . . . 487

68 . . . . . . . 141 158 . . . . . . 499

August 1994

Page 22

REFRIGERATION SERVICE

Torque Stem

Cap to 8-12 ft. lb.

Torque Stem

to 6-8 ft. lb.

CME500

General:

••Scotsman recommends that any work on the

refrigeration system only be done when it is
certain that the system needs repair.

Use

conservation minded service procedures:

••Refrain from checking refrigeration

pressures without reason.

ways to determine the proper operation of a
Scotsman ice machine without using refrigerant
gauges. Visual inspection of the water system,
observation of the ice formation, amp draw,
voltage, and other techniques will lead to proper
diagnosis. Scotsman also recommends that, at
the time of initial start up, gauges not be used.

There are many

••Refrigerant should not be added except as a

way to determine the proper operation of the
product. If the system was low on refrigerant,
there is a leak, and it must be found and
repaired.

••Refrigerant should not be wasted to the

atmosphere.

••This system has a critical charge, it must be

recharged with the correct amount of refrigerant
as listed on the nameplate of the ice machine,
or performance will suffer.

••Anytime the refrigeration system has been

opened, the dryer should be replaced.

Only a HFC type dryer should be used.

Note:

••When brazing the tubing connections to the hot

gas valve, the component must be protected by
heat sink material.

••If gauges must be used, do not always

check the high side pressure.

condenser is clean and seems to be operating
correctly, it most likely is. The low side pressure
is much more important on an ice machine than
is the high side.

If the

••If gauges must be used, use very short hoses.

Minimal refrigerant discharged into the hoses
equals minimal refrigerant discharged into the
air.

Recover, reclaim or recycle refrigerant.

spec 700-88. Reclaim programs are available
through most refrigerant wholesalers.

Access Valves: To use the access valves:
Remove the cap from the stem of the valve, then

use a 3/16" allen wrench to check that the valve is
closed. The core cap may then be removed.

Close the valve and replace the caps when the

Allen

Wrench

Access Valves

Note: There are no Schrader

valve cores in the valve.

job is finished. The valve must be closed and
the caps must be on or the valve will leak.

Torque Core

Cap to 7-12

ft. lb.

The method chosen is up to the service company.
There are various mechanical devices that may be
used to recycle refrigerant at the field level,
however, Scotsman requires that any refrigerant
placed into a Scotsman ice machine meet ARI

October 1994

Page 23

CME500

Removal and Replacement: Refrigeration System

If the refrigeration system must be serviced, the

quality of service must insure that there will
not be a repeat failure, as repeat failures will

cause refrigerant to be discharged into the air by
the failure or when the failure is corrected:

••If there has been a compressor burn out, check

for acid in the oil. If acid is indicated, extra steps
must be taken to clean up the system.

••Never use refrigerant to clean up or flush out a

refrigeration system. When system clean-up is
required, the use of suction line filter-dryers and
liquid line filter-dryers are recommended (they
must be compatable with polyolester oil and
HFC refrigerant).

••Always replace the dryer when repairing a leak

or replacing a refrigeration component.

••Evacuate the system with a good vacuum

pump to 200 microns or less. If the triple
evacuation method is used, the vacuum should
be broken each time with dry nitrogen, not
refrigerant. Evacuation must be from both sides
of the system.

••Weigh in or measure in the nameplate charge.

Recharge into the high side.

••Check for leaks with a high quality, electronic

leak detector capable of locating HP62.

••If using recycled refrigerant, it must meet ARI

spec 700 or have been cleaned by a machine
capable of attaining ARI spec 700-88.

If an ice machine is to be discarded and still
contains refrigerant, Scotsman recommends that
the refrigerant be recovered, reclaimed, or
recycled so that it is not discharged into the air.

August 1994

Page 24