Scotsman SLC300 Installation Manual

Introduction

SLC300

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 SLC300 is an ice machine that produces
cubed ice on 4 vertical cube freezing surfaces.

When harvested, the cubes fall individually into the
ice storage bin. The SLC300 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 R-502 as the
refrigerant.

Table of Contents

Specifications page 2

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

Installation

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4

Bin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 5

SLD dispenser . . . . . . . . . . . . . . . . . . . . . . . . . . page 6

RS or IS dispenser . . . . . . . . . . . . . . . . . . . . . . . . page 7

Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 8

Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 9

Final Check List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 10

Component Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 11

Initial Start Up page 12

Electrical Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 13

Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 14

Water/ Refrigeration Schematic . . . . . . . . . . . . . . . . . . . . . . . . . page 16

Technical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . page 18

Service Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 19

Removal and Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . page 21

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.

November 1994

Page 1

Water

Inlet

Serial Number

Plate

SLC300

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

SLC300 Cabinet

3

1

⁄8"

Electrical

Inlet

3 3⁄4"

SLC300 Back View

(Air Cooled Model Shown)

20"

Specifications:

The SLC300 will stack onto a

1

4

⁄4"

variety of ice storage bins, see
sales literature for proper ice
storage bin.

7

There is an optional stainless
steel panel kit, SPKSLC, for this

22"

⁄8"

Drain

machine.

Model Number Dimensions

W" x D" x H"

Condenser

Type

Basic

Electrical

Minimum

Circuit

Ampacity*

Maximum
Fuse Size (or
HACR circuit

Refrigerant

Charge. R-502

breakers)

SLC300AE-1E 22 x 23 x 20 Air 115/60/1 19.7 20 15 ounces
SLC300WE-1E 22 x 23 x 20 Water 115/60/1 18.2 20 16 ounces

* Minimum Circuit Ampacity is used to determine
wire size and type per the National Electric Code.

January 1993

Page 2

For The Installer: Environmental Limitations

23"

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

Minimum Maximum

0

Air Temp 55
Water Temp 40
Water Pressure 20 PSI 60 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. 900F.

SLC300

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 back.

Dashed Lines Show

Outline of Ice Drop

Area.

Bin Control Mounts to

Right of Ice Drop Area.

7"

3"

6

12"

1

⁄2"

SLC300

Top View

Do not install where this air flow is obstructed.

6" Space Required for

Air Flow (Air Cooled

Only) and Utility

Connections

November 1994

Page 3

SLC300

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 drains out some of the
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.

Location

This ice machine may be installed in the open or
under a counter. Clearance may be required at the
sides or top beyond what’s needed to place the
cabinet into position. Air cooled models take air in
the right side and exhaust out the back. Space is
required for 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.
Polyphosphate feeders are usually effective in
many water conditions.

Have the water tested. Acidic water or alkaline
water will both cause corrosion. Dissolved solids
cannot be filtered out. Softened water is not
recommended. Never use de-ionized water.
Reverse-osmosis water must be treated with
buffering agents before use in the ice machine.
Check with a water treatment specialist regarding
testing, treatment and filters.

January 1993

Page 4

Installation: Ice Storage Bin

SLC300

Assembly:

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

2. Be sure that the top edge of the bin has a good
gasket on it.

3. Place the ice machine onto the storage bin.

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

5. If on a Scotsman bin, attach the ice machine to
the bin using the straps and bolts shipped with the
ice machine. Drill two 1/8" holes in the back of the
bin and secure with sheet metal screws provided.
If on another brand bin, follow the directions
included with that bin.

Bin Thermostat Installation:

1. Remove thermostat bracket from package.

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 to the right of the cube drop area.

Stacking:

This machine will stack onto any SLC300 or
SLC400. Note: Do not use casters when stacking.

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

2. Remove knock out plug from top right panel.

3. Place gasket material around the top of the
bottom unit’s cabinet & evaporator compartment.

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

5. Align the two ice maker cabinets.

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

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

8. Route the bin thermostat capillary tube from the
upper unit, through the hole in the base, through
the lower unit and into the bin thermostat bracket.
Discard upper unit bracket.

Bin Thermostat

Installation

Bin Thermostat

Bracket

Thermostat

Capillary Tube

3. Locate and uncoil a portion of the
bin thermostat capillary tube. Route
the end of the capillary tube into the
plastic tube in the base of the ice
machine (next to the compressor) and
through the bin thermostat bracket.

Note: SLB150: Use thermostat

bracket packed with that bin.

Stacking

Routing Hole

Capillary Tube

Fasten Cabinets

Together At Back

With Straps &

Screws.

Bin Thermostat

Bracket

November 1994

Page 5

Bin Thermostat Capillary

Tube Installation

SLC300

Installation: SLD150 Hotel Dispenser

Assembly

The ice machine must be placed onto the top of
the dispenser, and the bin thermostat capillary
tube routed into the bracket in the dispenser.

1. Check that the dispenser has a gasket all
around the perimeter of the top, 22" wide by 23"
deep.

2. Locate the inlet hole of the thermostat bracket,
and make sure that it is open.

3. Place a corner post from the ice machine carton
at the front of left and right sides of the hotel
dispenser top.

4. Use a mechanical lift and place the ice machine
onto the dispenser. The cardboard corner posts
should keep the front edge of the ice machine up.

5. Remove the front panel of the ice machine.

6. Locate the bin thermostat capillary tube and
uncoil about 18" of tubing.

7. Locate plastic tube in base of ice
machine, next to compressor and
push the end of the capillary tube thru
the tube, watch the capillary as it
comes out of the base, line it up with
the inlet hole of the thermostat
bracket and push it into the hole.
Move the cabinet of the ice machine
until the capillary tube is going
straight down into the inlet hole.

8. Carefully remove the corner posts.

9. Push the capillary tube into the
thermostat bracket tube until about
14" of capillary tube is in the tube.

9 Remove the hardware package
from the machine, remove brackets.

10. At the back of the dispenser,
fasten brackets to the ice machine.

11. Using brackets for templates, drill
1/8" holes into the back of the
dispenser.

Route Capillary Tube

Through Plastic

Tube In Base

Bin Thermostat

Bracket Mounted In

Dispenser

Temporarily

Support Machine

With Corner Posts

To Observe Cap

Tube Installation

12. Secure brackets to the dispenser
with sheet metal screws from the
hardware package.

13. Follow other installation
instructions from the SLD150.

January 1993

Page 6

Installation: Scotsman IS or RS Dispenser

SLC300

Assembly:

The assembly of the ice machine onto the
dispenser requires two additional parts: an adapter
kit and a thermostat stand off kit.

1. Mark two spots on the inside left liner of the
dispenser: 2" down from the top, 4" from the back,
and 4" apart.

2. At the two marked spots, drill two 1/4" holes thru
the plastic liner only.

3. From the stand off kit, locate the stand offs and
plastic anchors. Thread the stand offs partially into
the plastic anchors.

4. Push the anchors/stand offs into the holes.

5. Screw the stand offs all the way into the
anchors. Be sure that the holes in the stand offs
are horizontal.

6. Place a bead of silastic (from the kit) around the
stand offs.

7. From the adapter kit, place the stainless steel
adapter onto the top of the dispenser. Follow all
directions included with the kit.

8. After the ice machine has been placed on the
dispenser, remove the front panel and uncoil all of
the bin thermostat capillary tube.

9. Route the capillary tube thru the front hole in the
base of the ice machine, to the left side if the
dispenser towards the stand offs.

10. Route the end of the capillary tube thru the
stand offs, bend the tube around the stand offs so
that it does not fall off.

11. Check that the routing of the capillary tube is
away from the ice chute and up high near the base
of the ice machine.

Installation of Bin Thermostat

Capillary Tube

K1 Kit Adapter

Stand Offs From Kit K6

Drill 2 Holes For

Stand-Offs:

2" From Top Of

Dispenser &

4" From Back &

4" Apart

Route Capillary

Tube Through Front

Plastic Tube

RS or IS

Dispenser

Route Capillary

Tube Through

Stand Offs

November 1994

Page 7

3/8" FPT Inlet

Water Cooled

Condenser Plumbing

Connections

SLC300

Installation

For The Plumber

Supply:

Screw the 3/8" male flare (fitting shipped in
package inside cabinet) into the 1/4" FPT fitting at
the back of the cabinet (thread tape
recommended). Connect cold potable water to the
water inlet. A hand shut off valve for inlet water
should be installed near the machine. 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.

Drains:

Connect a drain tube to the reservoir drain fitting at
the back of the cabinet. The drain tube from the
fitting must be run separately from any other drain
tube. 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.

Water Cooled: 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.

1/2" FPT

Outlet

Ice Storage Bin

(Typical)

Water Supply and Drain Connections

January 1993

Page 8

Installation

SLC300

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.

To make the electrical connections:

1. Remove the right top panel.

2. Remove the junction box cover.

3. Make the electrical connections to the wires in
the junction box. A ground screw is provided in the
junction box.

Hand Disconnect Switch

Junction Box

Follow All Local Codes - This Unit Must Be
Grounded. Usually a licensed electrician will be

required to connect the electrical service.

November 1994

Page 9

SLC300

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 and cabinet been wiped clean and
sanitized?

11. 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.

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

January 1993

Page 10

Component Location

ICE/OFF/WASH Switch

Bin

Thermostat

Ice/Off/Wash

Switch

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 pan

•• Ice size control adjustment

••

ICE/OFF/WASH switch

•• Control box

Ice Size

Thermostat

Compressor

Relay

SLC300

Control Box Detail

High

Pressure

Cut Out

Harvest

Relay

Water Distributor

Pan

Bin Thermostat

Bracket

Ice Thickness Control

Control Box

Bin Thermostat

Water Inlet Valve

& Strainer

Component Location

Water Pump

Drain Elbow

November 1994

Page 11

Correct Size &

Shape

Cube Size Diagram

Set

Screws

SLC300

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; the inlet water
valve will open, and water will flow into the
reservoir..

Ice Thickness

Probe Adjustment

2. Switch on the electrical power.

3. Remove the front panel.

3. Locate the ICE/OFF/WASH switch, switch

Up for LARGER

Down for SMALLER

it to WASH.

4. The water pump will begin to pump water over
the evaporators.

5. Allow the reservoir to refill. Normal water level is
1/8" below the high point of the lower curve of the
siphon u-tube.

6. Switch the ICE/OFF/WASH switch to OFF.

7. Check the action of the siphon. The water level
in the reservoir should drop to the bottom curve of
the U-bend (normal water level) in about 2
minutes. If not, check for proper drain tube
connections.

Ice Size Adjustment

Plate:

Cubes Too

Thick

8. Switch the ICE/OFF/WASH switch to ON.

9. On air cooled models the fan motor will begin to
turn, and warm air will be discharged from the
back of the ice machine.

On water cooled models warm water will begin to
flow from the condenser drain.

10. The water temperature in the reservoir will
soon be 32

0

F., and ice should begin to form on the

evaporators.

11. Allow the ice machine to operate for about
15-20 minutes. The ice should be fully formed and
should be harvested within a few minutes.

12. After harvest, check the ice cube size.

Compare a fresh cube to the diagram on the
back of the front panel. If needed, adjust the

cube size by loosening the two set screws and
moving the ice thickness probe plate.

Move the plate down for smaller cubes and up
for larger. Re-tighten set screws.

For proper operation, the ice thickness should be
set to the 1

11

⁄16" diameter.

The machine is designed to harvest cubes of
only the correct thickness.

1 11⁄16"

Cubes Too

Thin

January 1993

Page 12

Initial Start Up

SLC300

Note: If the first batch of cubes are not all uniform
discs, some ice machine cleaner should be added
to the reservoir.

1. After ice has been harvested, but before new
cubes begin to form, switch the ICE/OFF/WASH
switch to WASH.

2. Add 4 oz. of ice machine cleaner to the
reservoir. Allow unit to operate that way for 10
minutes.

3. Switch ICE/OFF/WASH switch to OFF

4. Shut the water supply off.

5. Remove the splash guard, and drain the
reservoir by removing the drain elbow.

7. Replace all parts, turn on the water and move
ICE/OFF/WASH switch to ICE. The next batch of
ice should be uniform.

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

14. Check operation of the bin control circuit by
holding ice on the bin control tube in the bin.

If the ice maker does not stop within 1 minute,
while keeping ice on the thermostat, rotate the bin
thermostat shaft counter clockwise until the ice
maker does stop. Remove the ice from the
capillary tube; the ice maker should restart within 2
minutes. If it does not, rotate the adjusting shaft
clockwise until the machines starts.

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

Siphon Tube Schematic

U-Tube Adjusted

Here = No Purge

Siphon Breaker Hole

U-Tube Here =

Maximum Purge

Water Level

At Harvest

Water Level With

Pump ON

Water Inlet

1/8 - 1/4

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.

Assume the bin thermostat is closed.
The ice size thermostat contact 2-3 are closed,

connecting power to:

••The fan motor (thru relay)

••The pump motor (thru relay and ice/off/wash

switch.

The Harvest Termination Thermostat is closed, but
there is no power thru it.

The ice size thermostat heater is on.

Harvest:

In the harvest cycle, the compressor is operating,
and the hot gas valve is energized. The water
pump is off, and air cooled models switch the fan
off.

The bin thermostat is still closed.
When the ice near the ice size thermostat sensing

tube grows large enough to force water over the
sensing tube, that tube looses heat, and at 38
contacts 2-3 open and 2-1 close.

This removes power from the water pump and fan
and connects power to the relay coil. When the
relay coil has power, it connects power to the:

o

••Hot gas valve coil

The harvest termination switch is closed, and
power flows thru it to the relay coil. This keeps the
relay energized, even when the ice size thermostat
switches contact position as a result of ice falling
away from the sensing tube.

The ice size thermostat heater is on.
The unit stays in the harvest cycle until the

thermodisc on the suction line warms up to 55
At that time the harvest cycle is terminated, and
the unit will go back into the freeze cycle.

Whenever there is ice on the bin thermostat, it
opens and stops the ice making process.

o

F.

F.,

Drain Outlet

Elbow

Bottom of
Reservoir

November 1994

Page 13

SLC300

Maintenance, Cleaning and Sanitizing

Cleaning Schedule:

••Scrub the outside of the cabinet once a week

with soap and water.

••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.

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. There is a strainer in the
water line; the strainer screen should also be
inspected for restricting minerals.

Air Cooled condenser (air cooled only):

Remove the right side panel.
The air flow thru the condenser is from front to

back, so dust will build up on the fan side of the
condenser fins.

The fan motor, bracket and part of the shroud may
be removed as an assembly:

1. Unplug the fan motor.

2. Remove 3 screws at the right edge of the fan
shroud.

3. Pull the assembly out the right side. The
condenser fins are then visible for cleaning.

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..

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.

Ice Storage Bin

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.
Once a week cleaning with soap and water, a hot
water rinse and an air dry is a basic procedure.

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 two
ounces 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.

To Remove Scale:

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

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.

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

Stainless Steel Bin Liner

The stainless steel liner of the bin will 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.

January 1993

Page 14

Cleaning: Ice Machine Water System

SLC300

Dissolve and Remove Minerals:

1. Remove front panel.

2. Move the ICE/OFF/WASH switch to OFF.

3. Remove the splash guard.

4. Shut the water supply off by pushing the water
valve button in.

5. Drain the water from the sump by removing the
drain elbow.

6. Disconnect hose from the water distributor pan,
and remove the water distributor pan.

7. Mix a solution of 5 oz. ice machine cleaner and
1 gallon of warm (95

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.

8. Wash the splash guard, drain elbow and water
distributor pan with the ice machine cleaner/water
solution.

9. With the solution of ice machine cleaner and
water, wash the refrigeration tubing, liner,
evaporators, support brackets and the water pump
assembly. Use the brush and/or a clean cloth.

10. Replace the drain elbow.

11. Open the water supply by pushing the water
valve button in to the original position and allow
the sump to refill.

12. Add 5 oz. ice machine cleaner to the sump
area.

13. Replace the water distributor pan and splash
guard. Be certain the hose to water distributor pan
is connected to pan.

o

F. - 115oF.) water.

15. Shut the water supply off by pushing the water
valve button in.

16. Drain the water from the sump by removing the
drain elbow.

Sanitize:

17. Remove the water distributor pan.

18. Mix a sanitizer solution of 1 ounce of
household bleach to 2 gallons of warm (95

o

115

F.) water

19. Wash the splash guard and the water
distributor pan with the solution of sanitizer. Allow
to air dry.

20. With the sanitizer solution, wash the
refrigeration tubing, liner, evaporators, support
brackets and water pump assembly; use the brush
and/or a clean cloth.

21. Replace the water distributor pan and splash
guard. Be certain that the hose to the water
distributor pan is tightly connected to the pan, and
that the flow washer in the hose is not in sideways.

22. Replace the drain elbow.

23. Add ice machine sanitizer solution to the sump
area until it is full.

24. Move the ICE/OFF/WASH switch to WASH
add more sanitizer solution to the sump area until
it is full again.

25. After 5 minutes, move the ICE/OFF/WASH
switch to OFF.

26. Remove the splash guard.

27. Drain the water from the sump by removing the
drain elbow.

28. Replace the drain elbow and splash guard

29. Open the water supply by pushing the water
valve button in (to the original position) and allow
the sump to refill.

30. Move the ICE/OFF/WASH switch to ICE.

31. Replace the front panel.

32. Discard first batch of ice and all other batches
until all traces of cleaner and sanitizer disappear.

o

F. -

14. Move the ICE/OFF/WASH switch to wash and
allow the solution to circulate for 15 minutes, then
move the ICE/OFF/WASH switch to OFF.

17. Remove the splash guard.

November 1994

Page 15

Discharge Line

Fan Motor

(On)

SLC300

Refrigeration Schematic:

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, the 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.

Melted ice and water spills into the bin flow
through a drain in the base of the bin to the
exterior drain connection at the back of the cabinet.

Evaporators

Inlet Water

Valve &

Strainer

Float

Valve

Water Distribution

System

Water
Pump

(On)

Thermostatic

Expansion Valve

Suction Line

Hot Gas Valve (Closed)

Condenser

Compressor

Dryer

Water Reservoir

Siphon

Tube

Refrigeration Schematic

January 1993

Page 16

Harvest Cycle:

Discharge Line

Fan Motor

(Off)

SLC300

The ice maker continures to freeze the water into
ice unitl the ice next to the ice size thermostat
probe has become thick enough to force water
over the probe. After the cold water has reduced
the temperature of the probe to 38

o

F., the ice size
thermotstat will switch the machine into the harvest
cycle.

During the harvest cycle, the refrigerant flows from
the condenser, 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.

Water Distribution

System

During the Harvest Cycle, the water level rises,
filling the reservoir over the siphon tube and
siphoning some of the reservoir water out to the
drain.

The harvest cycle continues until the suction line
warms up enough to cause the harvest termination
thermostat to switch the machine back into the
freeze cycle.

Evaporators

Inlet

Water

Valve

Water Reservoir

Water
Pump

(Off)

Siphon

Tube

(Draining)

Thermostatic

Expansion Valve

Suction Line

Hot Gas Valve (Open)

Condenser

Compressor

Dryer

Refrigeration Schematic

November 1994

Page 17

SLC300

Technical Characteristics

Typical Cycle Time

••16 minutes @ 90

Typical Harvest Ice Weight

••2.4 pounds .

Typical Low Side Pressure

••18-20 PSIG just before harvest

Typical Freeze Cycle Discharge Pressure

••190 - 240 PSIG @ 70

••250 - 290 PSIG @ 90

••250 for water cooled

Refrigerant Charge:

Air cooled = 15 ounces R-502; Water cooled = 16 ounces R-502

••

Harvest Time

••Normally 1

o

F. air and 70oF. water; 13 minutes @ 70oF. air and 50oF. water

o

F. air and 50oF. water

o

F. air and 70oF. water

1

⁄2 to 2 minutes. Depends upon time required to warm suction line to 55oF.

Typical Suction Pressure, In Harvest:

••105 -120 PSIG (@75

Typical Discharge Pressure, In Harvest:

o

F. air temp., will be lower in cooler ambients)

••120 - 150 PSIG

Water Cooled High Pressure Cut Out

••Cuts out at 380 PSIG, resets at 315 PSIG

Typical Compressor Amp Draw:

••6-7 during freeze cycle; 9-10 during harvest cycle

Compressor:

••Tecumseh AK9466J

Thermostatic Expansion Valve

••Superheat is 3

Bin Thermostat

••Cut out at 35

Ice Size Thermostat:

o

- 6oF.

o

F., cut in at 39oF.. Adjustable warmer.

•• Switches to harvest cycle with temperature fall to 38

oF.

Resets at 43oF.

Ice Size Heater

••

Adds heat to ice size thermostat to prevent premature harvest. 6,000 ohms resistance.

Harvest Termination Thermostat

•• Opens to switch to freeze cycle with temperature rise to 55

January 1993

Page 18

o

F. Resets at 40oF.

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 ICE/OFF/WASH
switch in OFF position

Unit off, due to bin thermostat
open

Water cooled unit off, due to high
pressure cut out open

No ice, compressor off No cooling due to compressor not

operating

No ice is made, compressor is
operating

No water due to water turned off. Reconnect water supply
No water due to water filter

plugged.
No water due to strainer screen

plugged
No water due to inlet water valve

will not open
Water in reservoir, but no water

over evaporators
No cooling at evaporator due to

hot gas valve leaking thru
No cooling at evaporator due to

fan not turning
Fan and pump do not have

power; hot gas valve opens and
closes.

No cooling at evaporator due to
dirty condenser

No cooling due to compressor not
pumping

Switch ICE/OFF/WASH switch to
ICE

Check temperature at bin
thermostat bracket, if warmer than

o

40

F., thermostat should be

closed. Adjust/replace thermostat.
Lack of water to condenser,

check water supply and water
regulating valve.

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

Check temperature of
compressor, if hot may be lack of
refrigerant, defective TXV or
compressor

Replace water filter

Clean out inlet screen

Replace valve

Water pump does not work,
replace pump

Replace hot gas valve

Check & replace fan motor.

Coil or relay open, replace relay.

Clean condenser

Check system pressures, replace
compressor if not pumping

SLC300

November 1994

Page 19

SLC300

Service Diagnosis:

SYMPTOM POSSIBLE CAUSE PROBABLE FIX

No ice compressor is operating No cooling due to low refrigerant

charge

Ice is made, but not harvested. Ice size thermostat contacts do

not switch position

Ice will not slide down ice rack
due to minerals on rack.

Ice will not slide down ice rack
due to ice rack out of position

Ice will not slide down ice rack
due to bent ice rack

Lack of heat during harvest cycle
due to unit in air temp. less than

0

55

F.

Lack of heat during harvest due to
water flowing thru water cooled
condenser

Lack of heat during harvest due to
lack of refrigerant

Lack of heat during harvest due to
hot gas valve not opening fully.

Ice does not slide down face of
evaporator due to minerals on
evaporator surface

Harvest cycle too short due to
harvest termination thermostat
opens at too low a temperature.

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

Ice not made near thermostat
probe due to water distributor
holes restricted. Clean water
distributor pan.

Thermostat defective, replace it
Clean machine with ice machine

cleaner.
Reposition ice rack

Replace ice rack

Warm up air or move machine.

Replace water regulating valve

Check low side pressure during
harvest. If low either the charge is
low or the hot gas valve does not
open fully. If charge is the
problem, locate leak, recover
remaining refrigerant, repair leak,
replace drier, evacuate and weigh
in nameplate charge.

Check low side pressure during
harvest. If low either the charge is
low or the hot gas valve does not
open fully.

Clean water system with ice
machine cleaner

Replace harvest termination
thermostat

January 1993

Page 20

SLC300

Service Diagnosis:

SYMPTOM POSSIBLE CAUSE PROBABLE FIX

Ice is made, but will not harvest Will not harvest due to hot gas

valve not opening.

Slow/incomplete harvest due to
hot gas valve not fully open.

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

dirty condenser; faulty fan motor;
not enough water thru water
cooled condenser, high water
temperatures, water reg. valve set
too high.

Inlet water temperatures and
room ambient very high

Long freeze cycle due to hot gas
valve leaking thru.

Compressor inefficient Check/replace compressor

Cubes are wrong size/shape Ice size thermostat not adjusted

properly
Freeze cycle too short due to

heater open
Water system is restricted with

minerals
Ice thickness probe tube covered

with minerals
Not enough water Check water supply pressure

Too much superheat Check superheat, replace TXV if

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.

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

Check low side pressure in
harvest, replace hot gas valve if
too low with correct ref. charge.

Check for causes of high
discharge pressure and correct.

Advise user, suggest additional
room cooling.

Check temperature of tubes to
and from hot gas valve; there
should be a temperature drop
across the valve in the freeze
cycle. Replace valve if temps are
nearly equal.

Adjust ice size thermostat; use
gauge shipped with machine

Check/replace heater on ice size
thermostat probe tube.

Clean water system with
Scotsman Ice Machine Cleaner

Clean tube with ice machine
cleaner

Check water supply for restrictions

too high.
Check hot gas valve for leak-thru;

replace if leaks thru.

to ease removal

November 1994

Page 21

Replacement of Ice Size Thermostat

Probe Tube

& Bracket

SLC300

Removal and Replacement

Ice Size Thermostat:

Before replacing the ice size thermostat, it should
be positively determined that it is at fault.

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 ice size thermostat.

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

Primary Resistor (Heater)

1. Disconnect electrical power.

2. Disconnect the primary resistors yellow wire
from terminal #4 and the white wire from terminal
#1. Pull the two wires out of the control box and
thru the insulated wall.

3. Mark location of adjustment bracket.

4. Remove two screws and the ice size thermostat
probe tube bracket.

5. Remove the evaporator side plastic sleeve and
heater from the tube.

6. Reverse the prior steps to replace. Probe tube
must be inserted into plastic guide attached to
evaporator.

7. Place adjustment bracket in its original position.
Check ice size.

Evaporator

Heater

6. Pull the three wires off the posts of the ice size
thermostat.

7. Locate bulb on suction line.

8. Follow the capillary tube of the ice size
thermostat: the end of the ice size thermostat is
inserted in a tube. Pull it out of the tube.

9. Pull the capillary tube of the ice size thermostat
thru the grommet in the side of the control box.

10. Remove the ice size thermostat from the
control box.

11. Replace the ice size thermostat with the proper
part number, following the above steps from 10-1.

Capillary

Tube

January 1993

Page 22

Removal and Replacement

SLC300

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
machine is in the freeze cycle.

1. Unplug or disconnect the electrical power.

Electrical shock hazard.

Electrical shock can
cause personal injury.

Disconnect power before
beginning to service
components.

Inlet Water Valve

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 top of the valve, and
pull the water inlet tube out of the valve body.

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

4. Remove the valve from the ice machine.

5. Reverse the above steps to reassemble.

2. Unplug the pump from its connection.

5. Loosen the two fasteners holding the cover to
the wall.

6. Remove pump cover from the machine.

7. Pull discharge hose from pump discharge port.

8. Remove pump from ice machine.

9. Reverse above steps to replace.

Shut Off Valve

Inlet Water Valve &

Strainer

Float Valve

Siphon "U" Tube

Pump Cover

Thumb

Screws

Replacement of Water

Pump

November 1994

Page 23

SLC300

Removal and Replacement: Refrigeration System

General:

••Scotsman recommends that any work on the

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

••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 must not be vented 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.

••When brazing the tubing connections to the hot

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

Specifically:
Recover, reclaim or recycle refrigerant. 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
spec 700. Reclaim programs are available through
most refrigerant wholesalers.

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

••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.

••If hi side pressure must be checked, use a

quick connect at the end of the discharge

to minimize the release of refrigerant, J/B

hose

Industries part number A33000 works well.

••If using recycled refrigerant, it must meet ARI

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

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, such as R-11, 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.

••Always replace the dryer when repairing a leak

or replacing a refrigeration component.

••Evacuate the system with a good vacuum

pump to 500 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. Halide torches will not locate the
very small leaks.

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.

January 1993

Page 24