Scotsman ND550 Operator’s Manual

INTRODUCTION

ND550

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 ND550 is a combination nugget ice maker and
countertop dispenser, with the option of wall
mounting. A water station may be added, if desired.

The ND550 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 R502
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.

TABLE OF CONTENTS

For the Installer

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Environmental Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Wall Mount Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Glass Filler Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Soda Valve Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

For the Plumber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

For the Electrician . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

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

Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Component Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

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

Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Maintenance and Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Service Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Removal and Replacement

Water Reservoir . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Bin Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Breaker and Bearing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Auger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Water Seal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Evaporator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Gearmotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Electronic Tester . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Parts Lists and Wiring Diagrams are printed on yellow paper in the center of this manual.

December, 1988

Page 1

115/60/1
115/60/1
115/60/1
115/60/1

16.7

16.2

16.7

16.2

Minimum

Circuit

Ampacity+

Basic

Electrical

20.5"

6.43"

ND550

FOR THE INSTALLER: Specifications

This ice maker-dispenser is designed to be
mounted on a machine stand, or a countertop, or
using wall mounting kit KWB3, hung from a wall.
The sink may be retained, or removed and the
optional longer splash panel (KSP1B) installed in
place of the original. Instructions for each kit are
included in this service manual.

NAMEPLATE

on inside of

right side panel

14.06"

1.88"dia

Before beginning the installation, check that all the
materials and kits required are available at the
installation location.

3.54"

4.5"

2.56"
3/8" FPT

Condenser
Water Inlet
(Water Cooled)

ELECTRCIAL JUNCTION BOX

Optional for water and

drain lines

22.5"

1/2" FPT
Cond. Drain
(Water Cooled)

3/4" FPT
Drain

SPECIFICATIONS

Model Number Cabinet

Dimensions

(w/o stand)

Ice

Type

H" x W" x D"

ND550AE-1A

ND550WE-1A

ND550AS-1A

ND550WS-1A

41 x 26 x 22.5

same
same
same

NUGGET

same
same
same

Condenser

Type

Air

Water

Air

Water

Finish

Painted

Painted
Stainless
Stainless

3/8" Flare
Potable Water Inlet

12.27"

1.12"

5.12"

3.12"

Maximum

Fuse

Size

20
20
20
20

+ Minimum Circuit Ampacity is used to figure wire size and type per National Electric Code.

August, 1989

Page 2

6" SPACE

FOR AIR

(AIR COOLED)

6" SPACE

FOR AIR

(A/C)

ND550

FOR THE INSTALLER: Environmental Limitations

Installation Limitations

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.

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.

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

Specifications and design are subject to change
without notice.

Water Limitations

An ice machine is a food manufacturing plant; it
takes 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. This section is not intended as a
complete resource for water questions, but it does
offer these general recommendations:

1. Filter the water used to produce ice. That is the
water going to the "potable" water connection.
Water filters vary greatly in ability and function.
Install one that filters out suspended solids to a
dimension of 5 microns or smaller. The finer the
filter the better, but finer filters will clog sooner
than course ones. It may be necessary to add a
course filter ahead of the fine filter to prolong filter
life.

2. Check with a water treatment specialist for a
water test, and recommendations regarding filters
and treatment.

Service Limitations

Do not install in a location where the top of the
machine is within 6" of a fixed ceiling. Do not install
air cooled models in a location where there is less

CUT AWAY

December, 1988

than 6" clearance to the left and right of the
cabinet.

CEILING

CUT AWAY

WALL

SPACE

FOR

UTILITIES

Page 3

SPACE
ABOVE

FOR

SERVICE

ND550

FOR THE INSTALLER

Location

After uncrating and inspection, the unit is ready for
installation. It is important that the machine be
installed in a location where it has enough space
above and behind it for service. Air cooled models
require a minimum of 6 inches to the left and right
of the machine for air circulation.

Machine Stand Installation

Tip the stand on it’s 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 "feet" on the icemaker-dispenser.
Place the cabinet onto the machine stand, so that
the unit "snaps" into place.

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.

SEAL THE

UNIT TO

THE

COUNTER

OR STAND

August, 1989

Page 4

BASE
HOLE

ND550

FOR THE INSTALLER: Wall Mount Kit

/////////////////////////WARNING///////////////////////////////
It is recommended that the wall mounting

installation be done by an experienced contractor.
The weight of the machine when in use may
exceed 350 pounds. The unit should be mounted
on a solid, rigid wall with proper fasteners for that
type of wall and of adequate strength to support
the weight of the machine when in use.

/////////////////////////////////////////////////////////////////////////
Clearance between the wall and the icemaker is a

maximum of 1 inch. Check utility connections first.
The electrical junction box will have to be
removed, and the electrical connections made
inside the cabinet in compliance with local codes.
The plumbing connections may be made through
the base, or at either side through the pre-punched
holes, using standard plumbing practices.

Interior plumbing lines must be disconnected from
the original connections and plugged when routing
through the side or base.

1. Remove machine top. Attach bracket "A" to
machine using (3) nuts, (3) flat washers, (3)
lockwashers, and (3) 5/16-18 bolts received with
the kit.

30"

7.58"

SIDE

ROUTING

1" CLEARANCE

16"

16"

A

DO NOT LIFT ON SINK

2. Mount brackets "B" and "C" to the wall at the
dimensions shown for the unit. (hardware for this is
not included).

B

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

Use fasteners and wall of sufficient strength to
carry the use and weight of the
icemaker-dispenser.

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

3. Lift unit up and hook bracket "A" over bracket

12"

12"

"B". Slide unit until the two remaining holes are
aligned and secure with the remaining (2) 1/4-20
bolts, flat washers and lockwashers.

C

December, 1988

Page 5

ADAPTER

FILLER

PLATE

ND550

FOR THE INSTALLER: Water Glass Filler Kit

Installation Instructions for KWGF

///////////////////////////CAUTION////////////////////////////////
Shut off potable water supply to icemaker -

dispenser.
/////////////////////////////////////////////////////////////////////////
///////////////////////////WARNING////////////////////////////

Disconnect electrical power to icemaker ­dispenser.

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

1. Remove screws, and remove top panel

2. Remove screws, and remove both front panels.

3. Remove screws, and remove the filler
plate-scrap the plate.

4. Locate water solenoid valve assembly and two
red wires in the kit. Attach the (2) red wires to the
solenoid terminals.

5. Locate the water line assembly and the water
line adapter. Connect to water solenoid valve.
Fitting size will determine location.

6. Remove plug from potable water line.

7. Install valve plate and switch assembly to the
dispenser, replace the filler plate removed in step

3.

8. Attach the water solenoid
assembly to the underside of the
upper compartment using (2)
screws and lockwashers into the
threaded holes provided.

9. Attach the water line adapter
and solenoid valve assembly to
water line where plug was removed
in step 6.

10. Attach clamp and #8-32 x 3/4
phillips machine screw to secure
the water line assembly.

11. Insert glass filler lever through
the square slot in the valve plate
and switch assembly. Attach to
dispenser with (2) arm clamps and
(2) #6-32 x 1/2 machine screws.

12. Check and adjust the
microswitch so that the glass filler
lever pushes the micro-switch
button.

13. Attach the glass filler lever
spring to glass filler lever. The large
hook goes to the filler lever, the
small one to the hole in the
dispenser base directly below.

PLUG

August, 1989

Page 6

14. Attach the red wire connected to the solenoid
to the switch on the valve plate. Attach the blue
wire to the switch on the valve plate.

••Route the free red wire from the solenoid,

attach to the terminal strip to the second
terminal from the left.

••Route the blue wire from the switch to the

control box, attach the red wire to the terminal
strip and attach the blue wire to the leftmost
terminal.

15. Turn on water, check for leaks. Replace
panels, switch on power supply, check operation.

TOP PANEL

ARM CLAMPS

SPRING

SWITCH

PLATE

ASSEMBLY

VALVE

CLAMP

WATER

LINE

ND550

FOR THE INSTALLER: Soda Valve Kit

Installation Instructions

Note: Carbonator and carbonated product cooling
system are not included.

//////////////////////////WARNING////////////////////////////

Disconnect electrical power to the icemaker ­dispenser.

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

1. Remove cabinet top panel, front panel, and
splash panel.

2. Remove screws and remove filler plate from the
ice maker dispenser.

3. Remove large plug from base of
icemaker-dispenser.

4. Install valve assembly in the ice machine with
two screws through the same holes that held on
the valve cover plate. Install 1-3/8" ID insulation
tube over the syrup and carbonated lines.

5. Route product lines through the hole in the base.

6. Make all required connections soda line
connections, using field supplied materials. All
lines should be insulated. A carbonated water
recirculating line is provided and recommended to
insure that high quality drinks are dispensed.

7. Install transformer in upper compartment of
icemaker-dispenser, using screws provided. It may
be necessary to pre-drill holes.

8. Route drink valve assembly electrical leads up
to the transformer.

9. Connect wire leads from the drink valves to the
24 volt output side of the transformer.

10. Locate a 115 volt continuous power source
from within the icemaker control box. Route white
and black leads from the 115 volt input side of the
transformer and connect to the 115 volt power
source.

11. Turn on power and soda equipment, check
operation and check for leaks. Adjust valves for
proper mixture.

115 VOLT
CONNICTION

ATTACH DRINK VALVE
ASSEMBLY HERE

TRANSFORMER

24 VOLTS

SODA VALVES

SODA
LINES

December, 1988

Page 7

ND550

FOR THE PLUMBER

CONFORM TO ALL APPLICABLE CODES

Water Inlet

Air Cooled Models: The recommended water

supply is clean, cold water. Use 3/8" O.D. copper
tubing, connect to the 3/8" male flare at the back
of the cabinet. Install a hand valve near the
machine to control the water supply.

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: A separate 3/8" O.D.
copper line is recommended, with a separate hand
valve to control it. It is connected to a 3/8" FPT
condenser inlet at the back of the cabinet. The
water pressure to all lines must always be above
20 psig, and below 120 psig.

WATER INLET

CABINET

DRAIN

OPTIONAL

WATER

FILTER

Drains

Air Cooled Models: There is one 3/4" FPT drain

at the back of the cabinet, the drain line is of the
gravity type, and 1/4 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 3/4" rigid
tubing.

Water Cooled Models: In addition to the above
mentioned drain, a separate condenser drain must
be installed. Connect it to the 1/2" condenser drain
connection at the back of the cabinet.

WATER INLET

SHUT OFF

VALVE

VENTED

DRAIN TUBE

FLOOR DRAIN

WATER COOLED DETAIL

CONDENSER

WATER INLET

August, 1989

Page 8

POTABLE

WATER INLET

CABINET

DRAIN

CONDENSER

DRAIN

FOR THE ELECTRICIAN

CONFORM TO ALL APPLICABLE CODES

The electrical power to the unit is
supplied through 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.

ND550

ELECTRICAL

POWER

JUNCTION

BOX

December, 1988

Page 9

ND550

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?

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

BACK VIEW OF COMPLETED INTSTALLATION

ELECTRICAL?

LEVELED?

ICEMAKER

DISPENSER

PLUMBING?

Wall mounted only: Is the machine properly

installed and secured to the wall?

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

8. Have all of the shipping blocks been removed?

MACHINE

STAND

August, 1989

Page 10

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).

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 master switch on. The electrical start
up sequence is now on automatic:

A. There will be a short (15 second) delay before
the gearmotor starts.

B. After the gearmotor starts, the compressor will
start.

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.

5. The unit should soon be making ice. If desired,
the low side pressure may be checked: it should
be 30 PSIG + or - 4 PSIG.

The air cooled discharge pressure will depend
upon air and water temperatures, but should be
between 200 PSIG and 280 PSIG.

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

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

ND550

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.

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

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 by wiping
it with a mixture of 1 ounce of household bleach to
1 gallon of water, allow to air dry. Replace all
covers and panels. Switch the icemaker-dispenser
back on.

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 warranty registration card, and mail
it in to Scotsman.

11. Fill out the field Quality Audit form, and mail it
to Scotsman.

December, 1988

Page 11

EVAPORATOR

HIGH PRESSURE

CUT OUT

ND550

COMPONENT DESCRIPTION

Control Box: Contains the electrical controls that
operate the machine.

High Pressure Cut Out Switch: A manual reset
switch sensing the high side refrigeration pressure.
It is set to shut the machine off, and illuminate the
reset switch light 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.

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 over the chute.

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

Portion Control Knob:

CONDENSER

Turning this knob adjusts the
length of time of dispense.

Low Pressure Cut Out
Switch: A manual reset

LOW PRESSURE

control that shuts off the ice machine when the low
side pressure drops below a preset point, 0-4 psig.

ICE LEVEL SENSORS

CUT OUT

August, 1989

PORTION

CONTROL

Page 12

WATER LEVEL

SENSOR

RESERVOIR

CONTROL

BOX

DRAIN TUBE

ICE STORAGE BIN

GLASS FILLER LEVER

COMPONENT DESCRIPTION

ND550

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.

Motor: A permanent split capacitor 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

EVAPORATOR

AUGER

WATER SEAL

MOTOR

December, 1988

Page 13

PORTION

CONTROL

MODULE

ND550

COMPONENT DESCRIPTION: 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. The reset switch
is mounted on the circuit
board.

On/Off Switch: Manual
control for the machine.

Transformer: Supplies low
voltage to the circuit board.

Potential Relay: The
compressor start relay.

Reset Switch: Part of Circuit
Board, manual reset. Lights up
when unit shuts off from: ice
discharge chute being
overfilled (opening the
microswitch at the top of the
chute); low or high pressure
switches opening.

Portion Control Module:

Controls the amount of time
the dipensing drive motor is
on. The time is varied by
adjustine the portion control
knob.

POTENTIAL

RELAY

TRANSFORMER

ON-OFF SWITCH

CIRCUIT

BOARD

RESET

SWITCH

CONTACTOR

August, 1989

Page 14

ELECTRICAL SEQUENCE

ND550

Refer the wiring diagram as needed.

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

••

The bin empty light on the circuit board goes on

••There is a 15 second delay

••If there is enough water in the reservoir, the

circuit board will allow the machine to start up.

Start up consists of:

••The compressor relay and auger motor relay

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

••The auger motor starts, and the centrifugal

switch closes, connecting power to the
compressor contactor coil.

••The contactor is energized, connecting power

to the compressor, and the compressor starts.

••As ice goes past the ice level sensors, the bin

empty light will stay on, and the machine will
continue to run, unless the ice stays between
the sensors for more than 15 seconds (bin full).
At that point, the bin empty light goes out, and
the machine shuts down.

Shut Down consists of:

••The compressor relay opens.

••The compressor contactor opens

••The compressor stops

••The auger motor is run by the circuit board for

2.5 more minutes, clearing out ice in the
evaporator, and then

••The auger motor relay opens, and the auger

motor stops.

If the ice level sensor is clear (bin empty) for more
than 15 seconds, the machine will start up again.

Another purpose of the circuit board is to turn the
machine off if there is not enough water in the
machine.

••When the water level in the reservoir falls

below the water level sensor, the machine will
"shut down"

••If the high pressure control (cut out switch)

opens, the machine will stop immediately
(through the relays on the circuit board) and
cause the reset switch on the circuit board to
light up. It must be manually reset at the
control and at the reset switch on the circuit
board.

••If the low pressure control (cut out switch)

opens, the machine will stop immediately
(through the relays on the circuit board) and
cause the reset switch on the circuit board to
light up. It must be manually reset at the
control and at the reset switch on the circuit
board.

••If the spout switch opens, the machine will stop

immediately (through the relays on the circuit
board) and cause the reset switch on the circuit
board to light up. After it re-closes the reset
switch on the circuit board must be manually
reset.

••The master switch is the manual control for the

complete machine, but it is not a service
disconnect.

Ice Vending

••When the glass filler lever is pushed in the vend

switch closes. That energizes the portion
control module, which, depending upon the
setting of the portion control knob, will power
the agitator drive motor for a set length of time.

••Holding the glass filler lever in will not cause

additional dispensing. Releasing and
re-pushing the glass filler lever will repeat the
dispense cycle.

••When the water refills the reservoir, the

machine will start up again.

Separate from the circuit board:

December, 1988

Page 15

ND550

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.

Those models with a water dispensing station
have an additional water circuit to an electric valve.
When the water station glass filler lever is pushed,
a switch closes a circuit to the electric water valve,
and water is dispensed.

Adjustment of the Water Level

WATER RESERVOIR

WATER INLET

WATER DRAIN

WATER

LEVEL

WATER LINE FOR

OPTIONAL WATER

STATION

August, 1989

Page 16

OPERATION: Refrigeration

EVAPORATOR

ND550

Beginning at the compressor, the refrigerant 502 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.

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

REFRIGERATION

SCHEMATIC

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

LIQUID LINE

CONDENSER

HIGH

PRESSURE

CUT OUT

DISCHARGE

LINE

COMPRESSOR

THERMOSTATIC

EXPANSION VALVE

December, 1988

Page 17

AGITATOR

ND550

OPERATION: Ice Vending

When the ice dispensing glass
filler lever is pushed, an electrical
circuit is made to the portion
control module in the control box.
That module will energize the
agitator drive motor for a certain
length of time, depending upon the
setting of the portion control knob.

The dispensing takes place when
the agitator sweeps the ice over
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.

VEND SWITCH

GLASS FILLER

LEVER

BIN BOTTOM

ICE CHUTE

DRIVE MOTOR

SINK

August, 1989

Page 18

ND550

MAINTENANCE AND CLEANING

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
A Scotsman Ice System represents a sizable investment of time and money in any company’s

business. In order to receive the best return for that investment, it MUST receive periodic
maintenance.

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.

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

/////////////////////////////WARNING////////////////////////////

Electrical power will be ON when doing in
place cleaning. Switch it OFF before
completing the cleaning procedures.

///////////////////////////////////////////////////////////////////////////
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.

///////////////////////////WARNING//////////////////////////////

Scotsman Ice Machine Cleaner contains
Phosphoric and Hydroxyacetic acids. These
compounds are corrosive and 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.

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

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.

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.

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.

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.

//////////////////////////////WARNING///////////////////////////

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 with an approved
sanitizer using the directions for that sanitizer.

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

December, 1988

Page 19

ND550

MAINTENANCE AND CLEANING

///////////////////////////WARNING/////////////////////////////

Disconnect electrical power before beginning.
//////////////////////////////////////////////////////////////////////////

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
buildup.

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 grommets in the ice
chute, and wipe them clean.

BIN

CONTROL

SENSOR

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

A. Check the bearing by:

BIN CONTROL

SENSOR

BIN TOP

••removing the ice chute cover

CLEAN WATER

SENSOR PROBE

////////CAUTION//////

THE TIP IS
MADE OF GLASS
//////////////////////////////

ICE SWEEP

••unscrewing the ice sweep

••removing the water shed

••using a spanner wrench and unscrewing the

breaker cover.

••unscrewing the auger stud

Inspect the assembly, looking for wear.
See Removal and Replacement to replace

bearing or seals. Reverse to reassemble.

4. Check and tighten all bolts and screws.

August, 1989

Page 20

MAINTENANCE AND CLEANING

ND550

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.

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

2. Remove 3 hex studs holding ice chute cover to
ice chute, and remove cover.

3. Unscrew and remove ice sweep.

4. Loosen band clamp under ice chute, and
remove ice chute from evaporator.

5. Remove 4 allen screws holding breaker to
evaporator.

6. 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.

7. Replace the water seal.

8. Reverse to reassemble.

ALLEN

HEAD

SCREWS

BREAKER

AND AUGER

ASSEMBLY

December, 1988

Page 21

ND550

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

STATUS:

A. Check: Voltage to the unit, restore it if there is none. Compare to the nameplate.
B. Check: The master switch, switch ON if off.
C. Check: The 3 reset switches, (circuit board, high and low pressure): depress and release each

switch. If the still does not start, check: the spout switch; the high and the low side pressures.
D. Check the low pressure cut out, if closed, go to E; if it is open, it could be due to:

ICE MAKER DOES NOT OPERATE

••Low refrigerant charge

••The auger not turning

••Restricted system

••TXV not opening

1. Check the low side pressure, the low pressure cut out opens at pressure below 4 psig.
If open, reset and:

a. Check if the auger is turning, if it is not, remove the gearbox and:

Check for internal damage, repair and replace in the machine.
b. Check for low charge, add some refrigerant, if the unit will operate,(normal
low side pressure being about 30 psig) stop and look for a leak, repair, replace the

drier, evacuate, and weigh in the nameplate charge. If, with added charge, the unit

does not operate:

Check for a restricted system, replace the drier, evacuate, and weigh in a

nameplate charge.

Check for a Thermostatic Expansion Valve that does not open, if defective,

replace it. Replace the drier, evacuate, and weigh in the nameplate charge.

E. Check the high pressure cut out, if closed, go to F; if open:

1.The pressure control opens at 450 psig. Check the high side pressure, reset the control,
and observe: on water cooled, that water soon begins to flow from the condenser drain;
or, on air cooled, that the fan is forcing air through the condenser. If the unit trips out on
pressures below 450 psig, replace the control. If the pressures rise above the trip out
point, and the unit shuts down:

a. Check for adequate water flow on water cooled, if adequate, clean the interior
of the condenser. If the pressures are still too high replace the water regulating valve.
b. Check for adequate air flow on air cooled. Clean the condenser and (if used) the

filter. If the air flow is poor because of the installation, advise the user that the unit
should be moved, or the air around it kept cooler.

Check the fan motor for tight bearings and proper rotation.

Check that the fan blades are clean, and the fan secure to the fan motor shaft.

F. Check the spout switch. It opens from excess pressure of ice inside the ice chute: this should only
happen when the machine does not shut off when the ice storage bin is full. This switch will reset
when the ice melts, but the machine will not restart until the reset switch on the circuit board is
pressed.

G. Check the water level in the reservoir. The machine will not run if there is not enough water in the
reservoir.

August, 1989

Page 22

ND550

1. Restore/adjust water level. See the next step.

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

STATUS:

H. Check: The gear motor, if it will not run, the compressor will not run. If no power to it:

Check: The indicator lights on the circuit board, the bin empty light should be ON, the no water light
should be OFF .

1. If the bin empty and no water lights are off, check the transformer.

side should have between 110-120 volts. If the line side has the correct voltage and the

2. If the transformer is good, and the bin empty light is OFF, check the ice level sensors.

Testor Model NM1 into the circiut board.

3. If the transformer is fine, and the "no water" light is ON, check the water level sensor.

ICE MAKER DOES NOT OPERATE

a. Transformer "load" side should have 12 to 15 volts. If not, check the "line" side. The line

load side does not, replace the transformer.

a. Remove sensors by pulling them out of the ice chute grommets. Visually inspect them,
clean if needed.
b. Look through the ice chute "eye" hole for something blocking the ice chute.
c. If the unit still does not run, replace the ice level sensors.
d. If the bin empty light is still OFF, check the circuit board.

1. Unplug "opto trans" and "LED" connectors from the circuit board.

2. Plug "opto trans" and "LED" connectors from the Scotsman Electronic Control

a.Move the "bin full" switch on the tester to the full position. The bin full light
on the tester should be ON, if not, replace the circuit board.
If the bin full light on the tester is ON, move the tester switch to "bin empty"
the light on the tester should go OFF and the bin empty light on the circuit
board should go ON. If not, replace the circuit board. If it does as above,
and the machine still does not run, replace the ice level sensors.

a. Check the water level in the reservoir, restore if low. If the water level is ok:
b. Remove the water level sensor from the reservoir and clean the tip if dirty.
CAUTION: THE TIP IS MADE OF GLASS
c. Replace the water level sensor. If the no water light is still on, check that the
"water sen" plug is firmly plugged into the circuit board.
d. If the no water light is still on,

1. Unplug the "water sen" connector from the circuit board.

2. Plug "water sen" connector from the Scotsman Electronic Control tester into

the circuit board.

a. Move the water switch on the tester to "no water" and the no water light
on the circuit board should go on. If not, replace the board.
b. Move the water switch to the "water" position, the no water light should
go off, if not, replace the circuit board.
c. If after the above, the machine still will not run, replace the water level
sensor

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

MORE INFORMATION ON THE CIRCUIT BOARD TESTER IS LOCATED AT THE END OF THE
MANUAL.

December, 1988

Page 23

ND550

STATUS:

A. Check the compressor relay.

The relay is on the circuit board, if it does not supply power to the contactor coil, the
compressor will not run.

1. Check for power at the contactor coil, if none:

2. Check the contactor coil. If the coil is open, replace the contactor.

3. Check the auger drive motor centrifugal switch. If, when the drive motor is running,
contact 4 (black wire removed) has no power, and all of the above switches have been
checked, replace the centrifugal switch, or the drive motor.

4. If the compressor relay on the circuit board has power on the NO contact, but not on the COM contact,

replace the circuit board.

B. Check the compressor

1. Check the compressor start relay.

2. Check the start capacitor.

3. Check the windings of the compressor for open windings or shorts to ground.
Replace those items found defective.

GEARMOTOR OPERATES, COMPRESSOR DOES NOT

a. Check for power at the compressor relay at the circuit board.
If there is power at the relay, but none at the contactor coil,

Check for an open wire between the relay and the contactor.

August, 1989

Page 24

ND550

SERVICE DIAGNOSIS: Condition - Low Ice Production

STATUS:

A. Check the air cooled condenser for dirt. Clean as required. Check the head pressure on water

cooled. Adjust as required. If the head pressure is very high:

1. Air cooled. Check for high air temperatures, or restrictive air flow. Correct as needed.

B. Check the evaporator

1. Clean the evaporator, the mineral build up will adversely affect the ice machines production.

3. Check the low side pressure; normal is about 30 psig. If low, assume a refrigerant leak,

EVERYTHING IS OPERATING

2. Water cooled. Check for high water temperatures, or low water pressure.
Correct as needed.

3. The refrigerant may contain non condensable gases, purge, evacuate, and
recharge per nameplate.

2. Check the evaporator for water leaks, replace the water seal if found to be leaking.

locate, repair and recharge.

If no leak, the TXV may be restricted, defective or not adjusted properly. If needed,

replace the TXV, evacuate, and recharge per nameplate.

4. Check the insulation on the evaporator. It should be dry, with no wet spots or frost.
If the insulation has failed: replace the evaporator or add extra insulation in the form

C. Check the compressor.

b. if the amp draw is normal, pinch off the suction line to check the pull down capability

of the compressor. The compressor should pull down to 25 inches of vacuum and hold

of foam tape to the evaporator.

1. The compressor may be inefficient.
a. Check the amp draw, if low change the compressor.

there for three to five minutes.

December, 1988

Page 25

ND550

SERVICE DIAGNOSIS: Condition - Poor or No Ice Dispensing

STATUS:

A. Check for ice in the bin. If no ice, check the ice making system.

If the ice making system is normal, the demand for ice may exceed the quantity the icemaker

dispenser can produce. Check with the user on ice usage: advise the user that another

B. Check for motion in the agitator when the glass filler lever is pushed, if no motion: Check the vend
switch, if it does not close when the glass filler lever pushes in the actuator button, replace the switch.

replace the portion control module in the control box. If there is voltage, and the agitator

There is power to the unit, but no ice dispensed

machine may be needed.

1. If the vend switch does close, check for voltage at the agitator drive motor: if none,

motor output shaft does not turn, replace the agitator gear motor assembly.

If the agitator moves when it is supposed to, and there is ice, the dispensing cycle

should be fine. If no ice is dispensed, check for an obstruction in the ice chute.

C. No portion control.

1. Continuous dispensing when the glass filler lever is pushed in: Check for an open
potentiometer (portion control). If open, replace it.

If it is not open, replace the portion control module in the control box.

2. Very short dispensing: Check for a shorted potentiometer (portion control). If shorted,

If it is not shorted, replace the portion control module in the control box.

replace it.

August, 1989

Page 26

REMOVAL AND REPLACEMENT

ND550

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 mounting screws from reservoir

bracket, and remove reservoir from icemaker.

8. Reverse to reassemble.

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.

BIN CONTROLS

FLANGE HOLE

GROMMETS

FLOAT ASSEMBLY

BIN TOP

December, 1988

Page 27

Steps 5c - 6

ND550

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:
//////////////////////////////WARNING////////////////////////////
Disconnect the electrical power to the machine

at the building source BEFORE proceeding
with any repair.

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

1. Remove panels and disconnect electrical power.

2. Unscrew three studs and remove ice chute

cover.

3. Unscrew and remove ice sweep.

4. Remove insulation halves from outside of ice

chute, loosen band clamp under ice chute, lift up
and remove ice chute.

5. The breaker may be removed from the auger

and evaporator without disturbing the auger.
a. Use spanner wrench and 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, 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. 19-0609-01 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.

Steps 3 - 5a Step 5 b

ICE

SWEEP

BREAKER

BEARING

BREAKER

AUGER

STUD

August, 1989

Page 28

REMOVAL AND REPLACEMENT

ND550

//////////////////////////////WARNING/////////////////////////
Disconnect electrical power.
Note that the auger has very sharp edges,

handle with care.
//////////////////////////////////////////////////////////////////////////
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.

1. The top panel must be removed.

2. Remove ice chute cover.

3. Unscrew ice sweep.

4. Loosen band clamp and re move ice chute
body.

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

a. Unscrew 4 allen head cap screws holding
breaker to evaporator.

b. Lift up on breaker and remove auger fr o m
evaporator.

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

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

a. Use spanner wrench and unscrew
stainless breaker cover from brea ker (l ef t
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.

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 .

/////////// //// //// //// //// WARNI NG/// //// //// //// //// //// //// ///
Ice machine cleaner is an acid. Handle it with

extre me 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
fro m the auger, and inspect the auger for
minerals clean as required.

SLIDE HAMME R

PULLER

BREAKER

AND AUGER

ASSEMBLY

December, 1988

Page 29

FOOD GRADE

SILASTIC

SEALANT

HERE

ND550

REMOVAL AND REPLACEMENT: Water Seal

To Remove the Water Seal:

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

1. The gearmotor/eva porator 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 reta iner from
the grove under the water seal.

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

3. The part of the water seal that rot ates w ith
the auger must also be replaced. R emove the
old part fro m 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.

WATER

SEAL

RETAINING

RING

To Replace the Water Seal:

1. Lubricate the water seal with wate r, and
push the water seal into the bottom of the
evaporator slight ly past the grove for the snap
ring.

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

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

/////////////////////////////CAUTION///////////////////////////
Do not get any silastic onto the face of the

seal.
/////////////////////////////////////////////////////////////////////////

6. Allow the auger and seal to air dry unti l the
silastic is dry on the surface.

7. If the origin al wat er seal wa s leaki ng, it
would be a good idea to inspect the interior of
the gearmotor.

August, 1989

Page 30

REMOVAL AND REPLACEMENT

ND550

To Replace the Evaporator:

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

1. Discharge the refrigerant from the ice
maker.

2. Unsweat the refrigera nt connect ions:
a) At the thermostatic expansion valve outlet.
//////////////////////////////CAUTION///////////////////////////

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 disch arge chute in reverse
order of disassembly.

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 rea ssembly by reversing the
disassembly for the breaker & thrust bearing
assembly.

For Access to the Evaporat or
to Gearmotor bolts:

1. Remove upper front and top
panels.

2. Remove screws holding
control box assembly to the
cabinet, move the cont rol b ox out
of the way, temporarily secure to
cabinet.

3. Remove the upper half of the
ice chute.

4. Remove the ice sweep.

5. Loosen clamp under ice chute ,
and remove the lower half of the
ice chute.

6. Remove the 2 screws securing
the front porti on of the gear mot or
support to the cabinet

7. Move the the gearmotor ­evaporator to the righ t: space is
now available for re moval of the
evaporator and gearmotor bolts.
When reassembling, reverse the
above steps.

MOVE THE
GEARMOTOR ­EVAPORATOR

CONTROL

BOX

SCREWS

December, 1988

Page 31

ND550

TO REMOVE AND REPAIR THE GEARMOTOR ASSEMBLY

/////////////////////////////WARNING////////////////////////////
Disconnect electrical power before begining

removal procedures.
//////////////////////////////////////////////////////////////////////////

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

1. Remove the electrical wires from the gear drive
motor.

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 (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.

Note: If the gearcase cover or the gearmotor
assembly was replaced, the replacement part
MAY HAVE BEEN shipped with a certain number
of shims. The number of shims used must match
the number written on the gearcase cover. If there

were no shims on the new parts, do not use
any shims. Do not use the old shims.

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

August, 1989

Page 32

CENTRIFUGAL

SWITCH

ND550

TO REMOVE AND REPAIR THE GEARMOTOR ASSEMBLY

WATER SHED

GREASE SEAL

DRIVE MOTOR

GEARCASE

COVER

FIRST
GEAR AND
BEARINGS

SECOND GEAR

AND BEARINGS

ROTOR BEARING

ROTOR SHAFT

SEAL

GASKET

GEARCASE

/////////////////////////////WARNING////////////////////////////
Disconnect electrical power before begining

removal procedures.
//////////////////////////////////////////////////////////////////////////

December, 1988

Page 33

ND550

REMOVAL AND REPLACEMENT

INSTRUCTIONS FOR USING TESTER MODEL FC1 (Optional, order part no. A33942-001)
(These instructions assume that the unit will not run, and prior investigation of electric power,

controls, and mechanical parts indicates that the electronic circuit may be at fault.)
/////////////////////////////////////////////////////////////////////////////WARNING/////////////////////////////////////////////////////////////
These procedures require the machine to be connected to the power supply. The voltages of the

electronic circuit are very low, but HIGHER VOLTAGES ARE PRESENT IN THE UNIT. For
example, the relays on the circuit board are at line or high voltage. Do not touch anything but the
tester while the unit is being checked out.

Make all connections to the circuit board with the ELECTRICAL POWER OFF.

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

Bin Control

electrical power on, the master switch on, and all
reset switches "reset" .

1. Unplug "photo trans" and "LED" connectors
from the circuit board.

2. Plug "photo trans" and "LED" connectors from
the tester into the circuit board.

a. Move the "bin full" switch on the tester to Full.

The light on the tester should be ON.
If the light on the tester is not on, the circuit board

should be replaced.

Note: All testing is done with the

b. If the light on the tester IS on, move the "bin
full" switch to Bin Empty. The light on the tester
should go OFF, and the Bin Empty light on the
circuit board should go ON.

If the Bin Empty light is ON, wait 10-20 seconds for
the machine to start. If the machine starts, replace
the ice level sensors.

If the Bin Empty light does not come ON, the
circuit board should be replaced.

LED

SWITCH TO

“FULL”

PHOTO TRANS

LIGHT GOES

ON

LIGHT GOES ON

LIGHT GOES

OFF

SWITCH TO

“BIN EMPTY”

August, 1989

Page 34

REMOVAL AND REPLACEMENT

SWITCH TO

“NO WATER”

ND550

Water Level

1. Unplug "water sen" connector from control
board.

2. Plug "water sen" connector from Scotsman
tester into circuit board.

a. Move "water" switch on tester to No Water
position. The No Water light on the circuit board
should go ON. If not, replace the circuit board.

LIGHT ON

WATER SENS

b. Move the "water" switch on the tester to the
Water position. The No Water light on the board
should go OFF. If not replace the circuit board. If
the light does go off, replace the water level sensor.

LIGHT OFF

SWITCH TO

“WATER”

December, 1988

Page 35