Scotsman NDE754 Owner’s Manual

INTRODUCTION

NDE754

To the owner or user: The service manual you are
reading is intended to provide you, and the
maintenance or service technician with the
information needed to install, start up, clean,
maintain, and service this ice maker-dispenser.

The NDE754 is a combination nugget ice maker
and countertop dispenser. A water station is
standard.

Table of Contents

FOR THE INSTALLER: Specifications ······························ Page 2

FOR THE INSTALLER ······································ Page 3

FOR THE PLUMBER ······································· Page 4

FOR THE ELECTRICIAN ····································· Page 5

FOR THE INSTALLER: Final Check List ····························· Page 6

INITIAL START UP ········································ Page 7

COMPONENT DESCRIPTION ·································· Page 8

COMPONENT DESCRIPTION ·································· Page 9

Control Box ············································ Page 10

ELECTRICAL SEQUENCE ···································· Page 11

OPERATION: Water ······································· Page 12

OPERATION: Refrigeration ···································· Page 13

OPERATION: Ice Vending ···································· Page 14

CLEANING and SANITIZING ··································· Page 15

SENSOR MAINTENANCE ···································· Page 16

BEARING MAINTENANCE ···································· Page 17

AUGER MAINTENANCE ····································· Page 18

SERVICE DIAGNOSIS ······································ Page 19

CONTROL SYSTEM DIAGNOSTICS ······························ Page 20

REMOVAL AND REPLACEMENT ································ Page 21

REMOVAL AND REPLACEMENT: Bearing And Breaker ···················· Page 22

REMOVAL AND REPLACEMENT ································ Page 23

REMOVAL AND REPLACEMENT: Water Seal ·························· Page 24

REMOVAL AND REPLACEMENT ································ Page 25

TO REMOVE AND REPAIR THE GEARMOTOR ASSEMBLY ·················· Page 26

REFRIGERATION SERVICE ··································· Page 27

The NDE754 ice making section is equipped with
the following features: electronic controls for bin
level and low water; thermostatic expansion valve;
front service for most components; and R-404a
(HP62) refrigerant. The ice dispensing section is a
seamless plastic storage bin, with a stainless steel
ice agitator at the bottom to sweep the ice into the
dispensing chute.

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

Note this symbol when it appears.

It marks a possible hazard.

March 2000

Page 1

NDE754

FOR THE INSTALLER: Specifications

This ice maker-dispenser is designed to be
mounted on a machine stand, or a countertop.
Before beginning the installation, check that all the
materials and kits required are available at the
installation location.

Scotsman Ice Systems are designed and
manufactured with the highest regard for safety
and performance. They meet or exceed the
standards of U.L., N.S.F., and C.U. L.

3/8" FPT

Cond. Water

Inlet

(W/C)

1/2" FPT

Cond. Drain

(W/C)

3/4 FPT

Drain

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.

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

BACK VIEW

Water Limitations:

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

General recommendations

Electrical Junction

Box

3/8" Flare

Water Inlet

are:

1. Filter the water used to
produce ice.

2. Check with a water
treatment specialist for a water
test, and any

6.63"

12.5"

4.63"

recommendations regarding
filters and treatment.

.75"

Model

Number

3/4" FPT

Drain

5.59"

17.59"

Dimensions

(w/o stand)

H"xW"xD"

3.84"

Condenser

Type

2.63"

Refrigerant

Charge

(R-404A)

7.93"

Basic

Electrical

Minimum

Circuit

Ampacity*

NDE754AS-1 45.74 x 35.18 x 29.26 Air 32 115/60/1 18.1 25
NDE754WS-1 same Water 22 same 16.5 20

*Minimum circuit ampacity is used to determine wire size and type per National Electric Code.
Options: Machine stand DMS31. Portion control kit KPC750.

March 2000

Page 2

Maximum
Fuse Size

FOR THE INSTALLER

NDE754

Location

This ice system is designed to be installed indoors,
in a controlled environment.

Minimum Maximum

0

Air Temp 50
Water Temp 40

F. 1000F.

0

F. 1000F.
Water Pressure 20 psi 80 psi
Voltage 104 126
Operating the machine outside of the above

limitations, or outdoors, is potentially damaging to
the machine; also it is misuse of the machine
which may void the warranty.

Service Limitations

Do not install in a location where the top of the
machine is within 6" of a fixed ceiling. Air cooled
models require a minimum of 6 inches to the left
and right of the machine for air circulation. It is
important that the machine be installed in a
location where it has enough space above and
behind it for service.

After uncrating and inspection, the unit is ready for
installation.

Machine Stand Installation

Tip the stand on its back and install the legs, return
the stand to the upright position. Adjust leg levelers
so that the stand does not “rock”.

Counter Top or Machine Stand Installation

The base of the icemaker-dispenser must be
sealed to the object it rests upon. Food grade
silastic sealant such as Scotsman part number
19-0529-01 is recommended.

Place a bead of the sealant on the machine stand
or counter top to match the outside edge of the
cabinet base and sink.

The icemaker-dispenser is heavy: use of a
mechanical hoist is recommended to lift it to the
height required to install it.

The DMS machine stand has holes in the top that
match up with threaded holes in the base of the
machine. Secure the machine stand to the base
with 4 5/16" bolts.

In both counter top and machine stand
installations, wipe off and neatly smooth any
excess sealant. Level the machine stand and
cabinet.

Unpack and install the sink brackets. Fit the sink
assembly onto the two sink brackets, and press
onto the bead of sealant. Wipe off and neatly
smooth any excess sealant from under the sink
edge. Connect the sink drain to the dispenser drain
system.

Airflow

SEAL

ICEMAKER-

DISPENSER TO

THE COUNTER

TOP OR

MACHINE STAND

March 2000

Page 3

NDE754

FOR THE PLUMBER

CONFORM TO ALL APPLICABLE CODES

Water Inlet

Air Cooled Models: Connect a clean, potable

and cold water supply to the
back of the cabinet. Install a hand valve near the
machine to control the water supply. Use
copper tubing.

Water Treatment: In most areas, a water filter of
some type will be useful. In areas where the water
is highly concentrated with minerals the water
should be tested by a water treatment specialist,
and the recommendations of the specialist
regarding filtration and/or treatment should be
followed.

Water Cooled Models: Connect a separate
O.D. copper line, with a separate hand valve to

3

control it, to the

” FPT condenser inlet at the

8

back of the cabinet. The water pressure to all lines
must always be above 20 psig, and below 120
psig.

3

” male flare at the

8

3

8

“ O.D.

3

“

8

INLET WATER

Drains

Air Cooled Models: Connect a drain tube to the

3

“ FPT drain fitting (plastic) at the back of the

one

4

cabinet, the drain line is of the gravity type, and
inch per foot fall is an acceptable pitch for the
drain tubing. There should be a vent at the
highest point of the drain line, and the ideal drain
receptacle would be a trapped and vented floor
drain. Use only

WATER COOLED

CONDENSER

WATER INLET

Water Cooled Models: In addition to the above

mentioned drain, a separate condenser drain line
must be installed. Connect it to the ½ " condenser
drain connection at the back of the cabinet.

3

” rigid tubing.

4

CONDENSER

DRAIN

1

4

VENTED

DRAIN

OPTIONAL

WATER

FILTER

SHUT OFF VALVE

FLOOR DRAIN

March 2000

Page 4

FOR THE ELECTRICIAN

CONFORM TO ALL APPLICABLE CODES

Connect the electrical power supply for the unit to
the wires in the junction box at the rear of the
machine.

Check the nameplate (located on the back panel)
for the voltage requirements, and for the minimum
circuit ampacity. The machine requires a solid
chassis to earth ground wire.

The ice maker should be connected to its own
electrical circuit so it would be individually fused.
Voltage variation must remain within design
limitations, even under starting conditions.

All external wiring must conform to national,
state, and local electrical codes. The use of a
licensed electrician is required to
perform the electrical installation.

NDE754

POWER SUPPLY

ELECTRICAL

CONNECTION

March 2000

Page 5

NDE754

FOR THE INSTALLER: Final Check List

1. Is the icemaker-dispenser installed
indoors, in a location where the air and
water temperatures are controlled, and
where they do not go beyond design
limitations?

2. is there an electrical service
disconnect within sight of the installed
machine? Is the machine on a separate
circuit? Has the voltage been checked
and compared to nameplate
requirements?

3. Have all of the plumbing connections
been made and checked for leaks?

4. Has the machine been leveled?

5. Is there a minimum of 6 inches of
clearance at the left and right sides of an
air cooled machine?

ELECTRICAL?

LEVELED?

6. Is there a minimum of 6 inches of
clearance at the top and back of the
machine for service and utility
connections?

7. Is there a water shut off valve installed
near the machine?

8. Have all of the shipping blocks been
removed?

WATER

INLET?

DRAINS?

March 2000

Page 6

INITIAL START UP

Pre Start Inspection

1. Remove the two front panels.

2. Check that all shipping blocks have been
removed.

3. Remove any and all packing tape (check inside
the storage bin).

4. Inspect the interior of the machine for loose
screws or wires. Check that no refrigerant lines are
rubbing each other. Check that the fan blade on air
cooled models turns freely.

5. Check that the machine is installed correctly
according to the final check list.

Start Up

1. Go through the pre start inspection.

2. Open the water hand valve, observe that water
enters the water reservoir, fills the tube from the
reservoir to the evaporator and then shuts off.
Check for leaks.

3. Switch the mode switch to ON. The auger drive
motor and compressor start, beginning the ice
making process.

4. On air cooled models, warm air will begin to flow
from the condenser. Water cooled models will
begin to discharge warm water down the drain.

NDE754

7. Check ice dispensing by pushing in on the glass
filler lever. Ice dispenses are portion controlled; by
turning a knob, the length of time the unit
dispenses when the glass filler lever is pushed
(and the amount of ice dispensed) is adjusted.

8. Switch off the icemaker-dispenser, remove the
top panel and the top of the ice storage bin.
Sanitize the interior of the ice storage bin with a
locally approved sanitizer. A possible sanitizer is a
mixture of 1 ounce of household bleach to 2
gallons of water. Wash the interior of the bin with
the sanitizing solution. Replace all covers and
panels. Switch the icemaker-dispenser back on.

5. The unit should soon be making ice. If desired,
the low side pressure may be checked: it should be
38 PSIG + or - 4 PSIG.

The air cooled discharge pressure will depend
upon air and water temperatures, but should be
between 200 PSIG and 300 PSIG.

Water cooled discharge pressure should be about
245 PSIG. If needed, adjust the water regulating
valve.

The above numbers are for new, clean machines.
Field values may be somewhat higher or lower.

6. There are no adjustments to make, so replace
the panels.

March 2000

9. Give the owner/user the service manual, instruct
him/her in the operation and maintenance
requirements of the unit. Make sure they know who
to call for service.

10. Fill out the Customer Evaluation and warranty
Registration form, and mail it in to Scotsman.

Page 7

NDE754

COMPONENT DESCRIPTION

ICE LEVEL SENSOR

EVAPORATOR

DRAIN

TUBE

RESERVOIR

WATER

LEVEL

SENSOR

ICE STORAGE BIN

CONTROL BOX

GLASS FILLER

LEVER

CONDENSER

HI

PRESSURE

CUT OUT

LOW

PRESSURE CUT

OUT

Control Box: Contains the electrical controls that

operate the machine.
High Pressure Cut Out Switch: An automatic

reset switch sensing the high side refrigeration
pressure. It is set to shut the machine off if the
discharge pressure should ever exceed 450 psig.

Evaporator: A vertical stainless steel tube,
refrigerated, and water filled. In it there is a
stainless steel auger.

Reservoir: Float operated, it maintains the water
level in the evaporator at a constant level, it also
contains the water level sensor.

Water Level Sensor: Senses if there is water in
the reservoir to make ice out of. Will shut the
machine off it there is none.

Low Pressure Cut Out Switch: An automatic
reset control that shuts off the ice machine when
the low side pressure drops below a preset point,
15 psig.

Ice Level Sensor: An electronic “eye”, it senses
the presence of ice in the bottom of the ice
discharge chute. Operates to turn the ice machine
on and off automatically as the level of ice in the
bin changes.

Drain Tube: When uncapped and lowered, drains
the evaporator.

Condenser: Air or water cooled, where the heat
removed in ice making is discharged.

Ice Storage Bin Assembly: A plastic lined,
insulated cylinder that receives, stores and
dispenses the ice. Fresh ice enters at the top, and
when the bin is full enough the ice will be between
the ice level sensors, and the icemaking will stop.
Ice is dispensed through a chute at the bottom
front when the agitator assembly sweeps the ice
through the chute.

Glass Filler Lever: Pushing in on this lever
causes the ice dispensing cycle to occur.

March 2000

Page 8

COMPONENT DESCRIPTION

NDE754

Evaporator: A refrigerated vertical tube filled with

water and containing a water seal and auger.
Auger: A solid stainless steel double spiral auger,

it pushes the ice crystals up to the top of the
evaporator.

Water Seal: A two part “face” seal, the top half
rotating with the auger, the bottom half stationary,
the sealing action being where the two seal “faces”
meet.

Ice Sweep: A plastic cap with “fingers”. It revolves
with the auger to “sweep” the ice into the ice chute.

Breaker: Where the ice is compressed and much
of the extra water is squeezed out of it before it is
discharged into the bin.

ICE CHUTE

Motor: A split phase motor that drives the gear

reducer.
Thrust Bearing: As the ice is pushed up the

evaporator, the auger is thrust down, and pressure
from the auger thrust is taken up by this bearing.

ICE SWEEP

BEARING

BREAKER

AUGER

WATER SEAL

WATER INLET

GEAR MOTOR

EVAPORATOR

March 2000

Page 9

NDE754

Control Box

Contactor: A definite purpose contactor
connecting the compressor to the power supply.

Circuit Board: Controlling the ice machine
through sensors and relays. The sensors are for
ice level and water level. The relays are for the
gear motor (with a built in time delay to clear the
evaporator of ice when the unit turns off) and for
the compressor.

Mode Switch: Manual control for the machine.
Potential Relay: The compressor start relay.

Water OK Light

Control Board

Power Light

Service Light

Freeze Light

Bin Full

Light

LED1

Compressor

Relay

LED3

Auger

Relay

March 2000

Page 10

ELECTRICAL SEQUENCE

NDE754

There are 7 indicator lights on the control board:

WTR-OK. Water OK. Normal = Glowing. Glows

·

when there is water in the reservoir.

PWR-OK. Power OK. Normal = Glowing. Glows

·

when the control board has power and is
functional.

Service. Normally Off.

·

Freeze. Normally Glowing when making ice.

·

Bin Full. Normally Off when making ice.

·

LED1. Normally Glowing when making ice.

·

LED3. Normally Glowing when making ice.

·

If the machine is switched off at the mode switch,
but is otherwise ready to go, switching the mode
switch to ON does the following:

The PWR-OK light glows.

·

If there is water in the reservoir the WTR-OK

·

light glows.

After 10 seconds the Freeze, LED1 and LED3

·

lights glow and the machine starts up.

Start Up:

· The compressor relay and auger motor relay

become energized, connecting power to the
windings of the auger motor and contactor coil.

·

The contactor is energized, connecting power to
the compressor, and the compressor starts.

·

During normal operation ice passes between
the ice level sensors but only interupts their
infrared beam momentarily. The bin full light
remains off and the machine stays on until ice
builds up in the bin and blocks the path between
the sensors for 6 seconds or longer. When that
occurs the bin full light glows and the machine
shuts down.

Ice Vending

When the glass filler lever is pushed in the vend
switch closes connecting power to the ice chute
door solenoid and agitator drive motor.

Optional Portion Control: The portion control
module will power the agitator drive motor for a set
length of time. The amount of time is controlled by
the setting of the portion control knob,.

Holding the glass filler lever in will not cause
additional dispensing, unless the portion control is
set for continuous dispensing. Releasing and
re-pushing the glass filler lever will repeat the
dispense cycle.

March 2000

Shut Down:

The compressor relay opens, LED1 goes out.

·

The compressor contactor opens

·

The compressor stops

·

The auger motor stays on for 1 more minute,

·

clearing out ice in the evaporator, and then

The auger motor relay opens, LED3 goes out

·

and the auger motor stops.

The compressor will not restart until 2 minutes or
more have passed after the last shut down. If the
path between the ice level sensors remains clear
for more than 10 seconds the machine will restart.

Another purpose of the control board is to turn the
machine off when necessary:

When the water level in the reservoir falls below

·

the water level sensor’s tip, the WTR-OK light
goes out and the machine shuts down. When
water refills the reservoir the WTR-OK light
glows and the machine starts up again.

If the auger drive motor current becomes

·

excessive the compressor and auger drive
motor will be switched Off and the Service light
will blink. The control board will restart the auger
drive motor in 4 minutes. If during the first 60
seconds after restart the auger motor current
stays within limits, the compressor is restarted
and the machine returns to normal operation. If
the current is excessive within 60 seconds after
the restart, the process will be repeated once
more. If after that try the current is still
excessive the machine shuts down and must be
manually reset. The service light will then be
glowing continuously.

To Reset: Disconnect and reconnect power to
the ice machine.

Separate from the circuit board:

·

If the high pressure cut out switch opens the
machine stops immediately. It automatically
resets when the pressure drops below its cut in
point.

·

If the low pressure cut out switch opens the
machine will stop immediately. It automatically
resets when the pressure rises over its cut in
point.

·

The mode switch is the manual control for the
complete machine, but it is not a service
disconnect.

Page 11

NDE754

OPERATION: Water

Water enters the machine through the 3/8" male
flare at the rear of the cabinet, goes to a strainer
and then to the water reservoir which it enters
through the float valve. The water then goes out
the bottom of the reservoir tank to the bottom of
the evaporator.

Reservoir overflow, evaporator condensation and
water in the sink are all routed to the drain. Water
cooled models have a separate water circuit for the
cooling water: it enters the fitting at the rear, goes
to the water regulating valve, then to the water
cooled condenser and down the drain.
The water dispensing station adds an additional
water circuit. When the water station glass filler
lever is pushed, a switch closes a circuit to an
electric water valve, and water is dispensed.

Note: The correct water level is determined when

the machine is operating. Check the water level
and compare it to the line molded into the side of
the reservoir. The water level should be between

If needed, adjust the water level by bending the

WATER LEVEL

1

" above and

8

1

" below the line.

4

float arm.

RESERVOIR

RESERVOIR

OVERFLOW DRAIN

WATER

INLET

BIN DRAIN

SINK DRAIN

WATER VALVE

WATER SCHEMATIC

March 2000

Page 12

OPERATION: Refrigeration

NDE754

Beginning at the compressor, the refrigerant is
compressed into a high temperature gas. The
discharge line directs this gas to the condenser. At
the condenser (air or water cooled) the gas is
cooled by either air or water and it then condenses
into a liquid. This high pressure liquid then goes
through the liquid line to the expansion valve.

The thermostatic expansion valve meters liquid
refrigerant into the evaporator, the volume of liquid
refrigerant depending upon the temperature of the
evaporator; warmer evaporators get more
refrigerant and colder evaporators get less.

REFRIGERATION SCHEMATIC

(AIR COOLED SHOWN)

At the evaporator, the refrigerant enters an area of
relatively low pressure, where it can easily “boil off”
or evaporate. As it evaporates, it absorbs heat
from the evaporator and whatever is in contact with
it (such as the water inside it). After the evaporator,
the refrigerant, now a low pressure vapor, goes
through the suction line back to compressor, where
the cycle is repeated.

SUCTION LINE

THERMOSTATIC

EXPANSION VALVE

LIQUID LINE

CONDENSER

FAN MOTOR

DISCHARGE

LINE

EVAPORATOR

COMPRESSOR

March 2000

Page 13

NDE754

OPERATION: Ice Vending

When the ice dispensing glass filler lever is
pushed, an electrical circuit is made to the ice
chute door solenoid causing the ice chute door to
open. At the same time power is connected to the
agitator drive motor.

Dispensing takes place when the agitator sweeps
the ice through the ice dispensing chute: ice will
continue to discharge out this chute as long as the
agitator is turning. It stops when the agitator stops.

ICE DISCHARGE CHUTE

DOOR

SOLENOID

STORAGE BIN

ICE CHUTE

DOOR

ICE CHUTE

AGITATOR

AGITATOR

DRIVE MOTOR

VEND SWITCH

GLASS FILLER

LEVER

SINK

March 2000

Page 14

NDE754

CLEANING and SANITIZING

It is the USER’S RESPONSIBILITY to see that the unit is properly maintained. It is always preferable, and
less costly in the long run, to avoid possible down time by keeping it clean; adjusting it as needed; and by
replacing worn parts before they can cause failure. The following is a list of recommended maintenance
that will help keep the machine running with a minimum of problems.

Cleaning should be scheduled at a minimum of twice per year.

Sanitizing of the ice storage bin should be scheduled for a minimum of 4 times a year.

Electrical power will be ON when doing in place
cleaning.

ICEMAKING SYSTEM: In place cleaning

1. Check and clean any water treatment devices, if
any are installed.

2. Remove screws and remove the upper front
panel.

3. Move the ON-OFF switch to OFF.

4. Remove the cover to the ice storage bin, and
remove the ice.

5. Remove the cover to the water reservoir and
block the float up.

6. Drain the water reservoir and freezer assembly
using the drain tube attached to the freezer water
inlet. Return the drain tube to its normal upright
position and replace the end cap.

7. Prepare the cleaning solution: Mix eight ounces
of Scotsman Ice Machine Cleaner with three quarts
of hot water. The water should be between 90-115
degrees F.

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.

10. After all of the cleaning solution has been
added to the reservoir, and the reservoir is nearly
empty, switch the master switch to OFF.

11. After draining the reservoir, as in step 6, wash
and rinse the water reservoir.

To Sanitize:

Repeat steps 8-11, except substitute sanitizer
solution for the cleaning solution.

A possible sanitizer solution may be made by
mixing 1 ounce of household bleach and 2 gallons
of warm (95

12. Remove the block from the float in the water
reservoir.

13. Switch the master switch to ON

14. Continue ice making for at least 15 minutes, to
flush out any cleaning solution. Check ice for acid
taste - continue icemaking until ice tastes sweet.

DO NOT USE any ice produced from the
cleaning solution.

Be sure no ice remains in the bin.

15. Remove all ice from the storage bin.

16. Add warm water to the ice storage bin and
thoroughly wash and rinse all surfaces within the
bin.

17. Sanitize the bin interior, cover, door and
agitator with an approved sanitizer using the
directions for that sanitizer.

18. Replace the ice storage bin cover, and the front
panel.

o

F. - 115oF.) potable water.

8. Slowly pour the cleaning solution into the water
reservoir until it is full. Wait 15 minutes, then
switch the master switch to ON.

9. As the ice maker begins to use water from the
reservoir, continue to add more cleaning solution to
maintain a full reservoir.

March 2000

Page 15

NDE754

SENSOR MAINTENANCE

1. The ice machine senses water level by a probe
located in the water reservoir. At least twice a year,
the probe should be removed from the reservoir,
and the tip wiped clean of mineral build-up.

SLIDE SENSORS

UP TO REMOVE

2. The bin control uses devices that sense light,
therefore they must be kept clean enough so that
they can “see”. At least twice a year, remove the
bin control sensors from the ice chute, and wipe
them clean.

March 2000

Page 16

Clean the Probe's Tip with ice
machine cleaner and a clean,
soft cloth.

BEARING MAINTENANCE

NDE754

The bearing in the breaker should also be checked
at least two times per year.

A. Check the bearing by:

removing the ice chute cover

·

Ice Sweep

unscrewing the ice sweep

·

removing the water shed

·

Breaker

Cover

unscrewing the breaker cover.

·

Auger Stud

Cap Screw

unscrewing the auger stud

·

Inspect the bearing. There should be plenty of
grease in sight. If grease is needed the bearing
and breaker should be removed to check the
action of the bearing. It should rotate smoothly.

To remove the breaker remove the lower ice chute
then take out all four allen head cap screws and
pull the breaker off the auger and evaporator.

If the bearing only needs grease, inject grease into
the bearing using Scotsman grease needle pn
02-3559-01 and Scotsman bearing grease
cartridge, pn A36808-001. Be sure to inject grease
evenly and thoroughly.

See Removal and Replacement section to replace
bearing or seals.

Off

Reverse to reassemble.

March 2000

Page 17

Bearing

Needle, pn
02-3559-01

NDE754

AUGER MAINTENANCE

In some areas, the water supply to the ice maker
will contain a high concentration of minerals, and
that will result in an evaporator and auger
becoming coated with these minerals, requiring a
more frequent removal than twice per year. If in
doubt about the condition of the evaporator and
auger, the auger can be removed so the parts can
be inspected.

Note: Water filters can filter out suspended solids,
but not dissolved solids. “Soft” water may not be
the complete answer. Check with a water
treatment specialist regarding water treatment.

For more information on removal of these
parts, see REMOVAL AND REPLACEMENT.

Moving Parts Hazard.

Disconnect electrical
power to the icemaker ­dispenser before
beginning.

BREAKER AND

AUGER ASSEMBLY

Disconnect electrical power, and shut off the
water supply.

Use care when removing the auger, it has
sharp edges.

1. To remove the auger, remove the front and top
panels.

2. Drain evaporator using drain hose.

3. Remove bail clamp from over ice chute cover

and remove cover.

4. Unscrew and remove ice sweep.

5. Remove ice chute from evaporator.

6. Remove 4 allen screws holding breaker to
evaporator.

7. Pull up to remove auger.
After the auger has been removed, allow the auger

to dry: if the auger is not bright and shiny, it must
be cleaned.

Clean the auger and evaporator as required. DO
NOT HONE THE EVAPORATOR.

8. Replace the water seal.

9. Reverse to reassemble.

March 2000

Page 18

NDE754

SERVICE DIAGNOSIS

Symptom Possible Cause Probable Correction

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 low water level. Check water supply, filter, strainer,

Unit off due to ice level sensors
(photo-electric eyes) blocked.

Unit off due to scale on water level
sensor.

Unit off due to high pressure
control open.

Auger motor hums but does not
turn.

Unit is shut down Circuit board has shut ice machine

Low pressure control open Auger not turning due to: motor

No power to circuit board. Check harness

Circuit Board gear motor relay will
not close

Water level or ice level sensor
failed.

No ice, auger motor is turning Compressor contactor coil is open Check/replace contactor

Compressor will not start Check start capacitor.

Circuit board compressor relay will
not close.

Unit makes ice, but very slowly. High discharge pressure because

of a dirty condenser
Low capacity because the auger

and evaporator are coated with
mineral scale

Low suction pressure due to low
refrigerant charge

March 2000

Page 19

Switch master switch to ON.

float valve. Correct water supply.
Check/clean ice level sensors.

Clean water level sensor.

Check for water interruption (water
cooled) or fan motor failure (air
cooled).

Auger can’t turn. Circuit board has
not yet shut unit down.

down due to high auger motor amp
draw. Check for cause of high amp
draw, including bearings,
gearmotor condition and scale on
auger and in evaporator.

failure; auger relay failure on circuit
board; or gears stripped. Check
drive train.

TXV restricted or not metering.
Check bulb temperature.

Lack of refrigerant. Check for leak.
Check for a restricted system

HI or low pressure cut out open
Check, replace board

Check, replace sensor

Check start relay
Check compressor windings
Check, replace board

Clean the air filter and condenser.

Clean the water system

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

NDE754

CONTROL SYSTEM DIAGNOSTICS

The control system consists of:

Control Board

·

Water Sensor

·

Ice Sensors

·

High Pressure Cut Out

·

Low Pressure Cut Out

·

If the unit is OFF, check the control board:

1. Is the Power OK light on? If not check power to
the unit. If it has power, and the Power OK light is
NOT on, check the high pressure and low pressure
cut outs. If they are both closed, replace the board.
If the Power OK light is ON, go to the next step.

2. Is the Water OK light on? If it is, go to the next
step. If not, check the water level in the reservoir. If
there is water in the reservoir, check that the water
sensor is plugged in. To check the water sensor:

A. Unplug water sensor.
B. Pull water sensor from reservoir.
C. Place one ohmmeter lead on the sensor's plug

and the other on the sensor's tip. The meter should
show nearly zero resistance. If it reads infinite
resistance, check the tip for corrosion. If it is clean
and still reads open, replace the sensor.

OR connect a copper wire to the wire where the
water sensor plugs into and place the other end in
the water. The water OK light should go ON. If it
does not, replace the control board.

3. Ice sensor check. Is the Bin Full light Off? If it is
OFF and the Service light is Off, and the unit is not
running, replace the control board.

If it is OFF and the auger motor is running but the
compressor is not, check the compressor contactor
coil.

If it is on, the ice sensors may be blocked. Remove
them and check for mineral scale. Scotsman's test
box can also be used to determine if the ice
sensors or board are defective.

Using the tester:
A. Disconnect the ice sensors at the connection by

the ice chute. Connect the LED and PHOTO
TRANS wires to the control board's wires.

B. With the On - Off (mode) switch in either
position, move the Bin Full switch on the tester to
Bin Full - the tester's light will blink and after a few
seconds the bin full light on the control board will
come on. If not, replace the board.

Move the Bin switch on the tester to Bin Empty.
The light on the tester will go out, and after a few
seconds the Bin Full light on the board will go out.
If master switch is ON, the unit should start.

4. High pressure cut out check.
Disconnect electrical power.
Pull the wires off the high pressure cut out.
Use an ohmmeter to determine if the switch is

OPEN, If it is, check the discharge pressure. If the
discharge pressure is less than 300 PSIG, replace
the high pressure cut out.

If the high pressure cut out is open and the system
has high discharge pressure, check for the cause.

5. Low pressure cut out check.
Disconnect electrical power.
Pull the wires off the low pressure cut out.
Use an ohmmeter to determine if the switch is

OPEN, If it is, check the suction pressure. If the
suction pressure is greater than 35 PSIG, replace
the low pressure cut out.

If the low pressure cut out is open and the system
has low suction pressure, check for the cause.

March 2000

Page 20

REMOVAL AND REPLACEMENT

WATER RESERVOIR

1. Shut off the water supply to the icemaker.

2. Remove front panel and reservoir cover.

3. To remove float only, pry the mounting flanges
apart enough to lift one float pivot pin out of the
flange hole, and pull float up and out of the
reservoir.

4. To remove reservoir, disconnect water inlet
compression fitting at reservoir inlet.

5. Remove drain hose from reservoir.

6. Remove evaporator inlet hose from reservoir.

7. Remove water level sensor probe.

8. Remove mounting screws from reservoir
bracket, and remove reservoir from icemaker.

9. Reverse to reassemble.

FLOAT

ASSEMBLY

NDE754

Water

Sensor

LOCKING

TABS

BIN CONTROLS (Ice Level Sensors)

1. Disconnect electrical power.

2. Remove front panel.

3. Remove control box cover.

4. Locate bin top, in front of and behind it are two
rubber bin control grommets.

5. Pull each bin control out, and in the control box,
disconnect the electrical leads connecting the bin
control to the circuit board.

6. Reverse to reassemble, be certain that the bin
controls are aligned so that the ice level sensors
are visible (centered) through the holes in the ice
chute.

March 2000

Page 21

NDE754

REMOVAL AND REPLACEMENT: Bearing And Breaker

Note: Removal of the auger, water seal, evaporator
and gearmotor must begin at the top of the
assembly.

To Remove the Breaker Bearing Assembly:

Moving Parts Hazard.

Disconnect electrical
power to the icemaker ­dispenser before
beginning.

1. Remove panels and disconnect electrical power.

2. Unscrew three studs and remove ice chute
cover.

3. Unscrew and remove ice sweep.

4. Lift up and remove ice chute.

5. The breaker may be removed from the auger
and evaporator without disturbing the auger.

a. Unscrew breaker cover from breaker (left hand

threads)

b. Unscrew auger stud from top of auger.
c. Unscrew 4 allen head cap screws holding

breaker to evaporator.

ICE SWEEP

STEP 5-A STEP 5-B STEPS 5-C

d. Lift up, and remove breaker/bearing assembly

from auger & evaporator.

6. Service the bearing. Check for rust, rough spots
and damage.

a. The bearing is pressed into the breaker, to

remove the bearing and replace it an arbor press is
needed.

b. Replace lower seals before installing new

bearing in breaker.
Note: seals must be pressed in with a tool pushing

against the outer edge only, they will not install by
hand.

Replace parts as required. Re-grease bearing with
Scotsman part no. A36808-001 bearing grease.
Replace top seal, and check the o-rings, replace if
cut or torn.

7. Reverse to reassemble: specific tools and
materials are required to install properly.

a. Add food grade grease such as Scotsman part
number 19-0569-01 to the seal area before
installing on the auger.

b. Check the seal to shaft areas for cuts, or rough
spots: none are permitted.

BEARING

AND 6

March 2000

Page 22

BREAKER

REMOVAL AND REPLACEMENT

NDE754

To Remove the Auger:

Turn off the water to the machine, and unclip the
evaporator drain hose, pull it down and drain the
evaporator into the bin or a container.

Moving Parts Hazard.

Disconnect electrical
power to the icemaker ­dispenser before
beginning.

1. The top panel must be removed.

2. Remove ice chute cover.

3. Unscrew ice sweep.

4. Remove ice chute body.

5. The auger and breaker/bearing may now be
removed as an assembly.

BREAKER/

BEARING/

AUGER

ASSEMBLY

SHARP EDGES!

e. If the auger is stuck use a slide hammer type

puller to pull on the auger at the threaded hole.
The size of that hole is 5/8"-18.

Inspect the auger, the critical areas of the auger
are:

1. The auger body. It should be clean and

shining. Sometimes an auger will appear clean
when wet, but after it is dry it will be seen to be
stained. Scrub the auger with ice machine cleaner
and hot water.

Ice machine cleaner is an acid. Handle it with
extreme care, keep out of the reach of children.

2. The water seal area. Because the auger has

been removed, the water seal will have to be
replaced. Remove the water seal top half from the
auger, and inspect the auger for minerals clean as
required.

SLIDE HAMMER

PULLER

a. Unscrew 4 allen head cap screws holding

breaker to evaporator.

b. Lift up on breaker and remove auger from

evaporator.

Note: If the auger is stuck, the breaker must be
removed from the auger.

The breaker may be removed from the auger and
evaporator without disturbing the auger.

a. Unscrew breaker cover from breaker (left hand

threads)

b. Unscrew auger stud from top of auger.
c. Unscrew 4 allen head cap screws holding

breaker to evaporator.

d. Lift up & remove breaker from evaporator.

March 2000

THREAD INTO

AUGER

Page 23

NDE754

REMOVAL AND REPLACEMENT: Water Seal

To Remove the Water Seal:

(Assuming all steps to remove the auger have
been performed.)

1. The gearmotor/evaporator assembly will have to
be exposed. (See illustration - next page)

2. Remove the 4 hex head cap screws holding the
evaporator to the gearmotor assembly. Lift the
evaporator up and off of the gearmotor.

3. Remove the snap ring or wire retainer from the
grove under the water seal.

4. Pull or drive out the lower half of the water seal.

To Replace the Water Seal:

1. Lubricate the water seal with water, and push
the water seal into the bottom of the evaporator
slightly past the grove for the snap ring.

5. Carefully push the water seal (rubber side
against the auger shoulder and the silastic
sealant.)

Do not get any sealant onto the face of the seal.

6. Allow the auger and seal to air dry until the
sealant is dry on the surface.

7. If the original water seal was leaking, it would

be a good idea to inspect the interior of the
gearmotor.

WATER SEAL

RETAINING RING

2. Replace the snap ring and pull the water seal
down against it.

3. The part of the water seal that rotates with the
auger must also be replaced. Remove the old part
from the auger and clean the mounting area.

4. Place a small bead of food grade silastic sealant
(such as 732 RTV or Scotsman part number
19-0529-01) on the area of the auger where the
water seal is to be mounted.

March 2000

FOOD GRADE

SEALANT HERE

Page 24

REMOVAL AND REPLACEMENT

NDE754

To Replace the Evaporator:

(Assuming all the steps for removal of the thrust
bearing, breaker, auger, and water seal have been
performed.)

1. Recover the refrigerant from the ice maker.

2. Unsweat the refrigerant connections:
a) At the thermostatic expansion valve outlet.

Heat sink the TXV body when unsweating or
resweating the adjacent tubing.

b) At the suction line at the joint about 3" from the

evaporator.

3. Remove the evaporator.

4. Unsweat the drier from the liquid line.

5. After installing a new water

seal in the new evaporator
(see “To Replace the Water
Seal”) sweat in the new
evaporator at the old tubing
connections.

6. Install an new drier in the

liquid line.

7. Evacuate the system until

dehydrated, then weigh in the
nameplate charge. Check for
leaks.

8. Install auger, breaker,

breaker bearing assembly,
and ice discharge chute in
reverse order of disassembly.

EVAPORATOR

WATER

SEAL

RETAINING RING

DRIP PAN

To Reassemble the Evaporator and Auger

1. After the gearmotor has been inspected, fasten
the evaporator to the gear motor, be sure that the
number of shims indicated on the gear case cover
is in place between the gearcase cover and the
drip pan gasket. Torque the bolts to 110 inch
pounds.

2. Lower the auger into the evaporator barrel,
slightly turning it to match up with the drive end. Do
Not Drop Into the Evaporator.

3. Complete the reassembly by reversing the
disassembly for the breaker & thrust bearing
assembly.

BREAKER

ICE SWEEP

March 2000

Page 25

BREAKER

BEARING

AUGER

NDE754

TO REMOVE AND REPAIR THE GEARMOTOR ASSEMBLY

(Assuming that the procedures through removal of
the water seal have been performed.)

1. Remove the electrical wires from the gear drive

motor.

Electrical Shock Hazard.

Disconnect electrical
power to the icemaker ­dispenser before
beginning.

2. Unscrew the 4 cap screws holding the

gearmotor to the gearmotor plate.

3. Remove the gearmotor from the

icemaker.

To Inspect the gearmotor.

A) Remove the cap screws holding

the gearmotor case halves together
and pry the two cases apart.

B) To lift off the cover, lift up until

you can feel internal contact, then
pull the cover towards the output
gear end, and then lift the cover

GEARCASE

COVER

(with drive motor attached) up and
away from the gear motor case.

Note: The case cover output gear,
bearings, and shaft are one pressed
together assembly. Replace as a
unit.

C) Inspect the oil, gears, and

bearings. If the oil level and
condition is acceptable, quickly
check the gears and bearings. They
are likely to be fine if the oil is.

If there is evidence of water in the
oil (rusty bearings and gears; the oil
having a creamy white appearance;
oil level too high) carefully inspect
the bearings and gears. If in doubt
about the condition of a part,
replace it. The oil quantity is 14 fluid
ounces, do not overfill.

Note: The gears and bearings are
available only as pressed together
sets.

D) After replacing parts as required, (if any)
reassemble the gearcase. The two smaller gears
and the oil should be in the lower case, the output
gear will be with the cover. As you lower the cover
onto the lower case, cover will have to be moved
closer to the second gear after the output gear has
cleared the second gear top bearing.

E) After the case is together, and the locating pins
are secure in both ends, replace all cap screws.

4. Bench test the gearmotor, check for oil leaks,
noise, and amp draw.

WATER

SHED

MOTOR

GEAR &

BEARINGS

GEAR &

BEARINGS

GASKET

GEAR CASE

SWITCH

BEARING

March 2000

Page 26

REFRIGERATION SERVICE

SCALE

NDE754

General: This ice machine uses R-404A refrigerant
and polyolester oil. Do NOT use mineral oil in this
refrigeration system.

When the system is serviced, a special liquid

·

line drier is required. It is included with
replacement compressors.

R-404A is not compatible with mineral oil so

·

these ice machines use Polyolester oil.
Polyolester oil absorbs water very easily. A
system opened for service 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 Halongenated
refrigerant or HFC-134a will work. Check with
the leak detector manufacturer if in doubt.

Evacuate to 300 microns.

·

Liquid charge the system

·

Access Valves: To use the
access valves:

Remove the cap from the

·

stem, use a 3/16" allen
wrench to check that the
valve is CLOSED. The
remove the core cap.

·

Close the valve and
replace the caps when done. The valve must be
closed and the caps must be on or the valve will
leak.

Sight Glass

Torque stem

to 6-8 ft.-lb.,
caps to 7-12

ft.-lb.

R-404A
Tank Must
Be in Liquid
Dispensing
Position ­Check Tank!

Instructions for Liquid Charging R-404A

In preparation for charging, the low side hose
should have a sight glass, and/or a restricting
device (such as a “Charge Faster”) installed in it for
metering liquid into the low side of the system.

1. After a thorough evacuation shut off the manifold
valves and switch off the vacuum pump.

2. Place a drum of R-404A onto an electronic
scale.

3. Attach the charging hose to the drum.

4. Open the valve on the drum and purge the
charging hose.

5. Zero out the scale.

6. Shut the low side access valve at the ice
machine.

7. Open the discharge manifold valve full open.

8. Watch the scale, when the correct charge is

shown, shut the manifold valve.
Note: If all of the charge will not “go in” the

discharge side:
A. Shut the discharge access valve at the ice

machine.
B. Switch the machine on.
C. Open the low side access valve at the ice

machine.
D. Open the low side manifold valve and observe

the sight glass to be certain that only gas is flowing

into the system.
E. When the proper charge is indicated on the

scale, shut off the manifold valve(s).

9. Shut off the valve on the refrigerant drum.

10. Re-open the manifold valves until all liquid has

flowed out of the hoses.

11. Shut the low side access valve on the ice
machine.

12. Remove hoses from ice machine and replace
all caps.

Hose Connection Schematic for Liquid Charging

March 2000

Page 27