Scotsman NDE550 Service Manual

INTRODUCTION

NDE550 & NDE650

To the own er or user: The ser vice manua l you are
reading is intended to provide you, and the
mainte na nce or serv ic e te c h ni ci a n w i th the
information needed to install, start up, clean,
maintain, and service this ice maker-dispenser.

This ma c hi n e i s a c om b i na ti o n nugget ic e m ake r
and coun te r top dispens e r , w it h the opt i on of wal l
mounting.

The ice making section is equipped with the
followi n g features: electron i c con t rols for bin l ev e l
and low w at er ; thermostatic ex pansion va l ve; front
service for most co m ponent s; and R-404A (HP62)
refrigerant. The ice dispensing section i s a
seamless plastic storage bin, with a stainless steel
rotating vane to sweep the ice into the dispensing
chute.

Table of Contents

FOR THE INSTALLER: Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . 2

FOR THE INSTALLER: Environmental Limitations . . . . . . . . . . . . . . . . . . . 3

FOR THE INSTALLER: Wall Mount Kit . . . . . . . . . . . . . . . . . . . . . . . . . 5

FOR THE INSTALLER: Soda Valve Kit . . . . . . . . . . . . . . . . . . . . . . . . . 6

FOR THE PLUMBER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

FOR THE ELECTRICIAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

FOR THE INSTALLER: Final Check List . . . . . . . . . . . . . . . . . . . . . . . . 9

INITIAL START UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

COMPONENT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

COMPONENT DESCRIPTION: Control Box . . . . . . . . . . . . . . . . . . . . . . . 13

ELECTRICAL SEQUENCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

OPERATION: Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

OPERATION: Refrigeration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

OPERATION: Ice Vending . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

CLEANING and SANITIZING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

MAINTENANCE AND CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

SERVICE DIAGNOSIS: Condition - No Ice Being Produced . . . . . . . . . . . . . . 21

SERVICE DIAGNOSIS: Condition - Low Ice Production . . . . . . . . . . . . . . . . 24

SERVICE DIAGNOSIS: Condition - Poor or No Ice Dispensing . . . . . . . . . . . . . 25

REMOVAL AND REPLACEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

REFRIGERATION SERVICE: HP62 . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

REFRIGERATION SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

CIRCUIT BOARD TESTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

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

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

Note this symbol when it appears.

It marks a possible hazard.

April 1997

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NDE550 & NDE650

FOR THE INSTALLER: Env ironmental Limitations

Installation Limitations

This ice system is designed to be installed indoors,
in a cont r oll e d environm en t.

Minimum Maximum

0

Air Temp 50
Water Temp 40

F. 1000F.

0

F. 1000F.
Water Pressure 20 PSI 80 PSI
Voltage (115v) 104 126
Operating the machine outside of the above

limitations, or ou tdoors, is po tentially da m ag i ng to
the machine; also it is misuse of the machine,
which may void the warranty.

Scotsman Ice Systems are designed and
manufactured w ith the highest regard for safety
and performanc e. They meet or exceed the
standards of UL, NSF, and CUL.

Scotsman assumes no liability or responsibility of
any kind for pr o du c t s ma nu fa c t ur e d by Sc otsman
that ha ve been alt e r ed in any way, including the
use of any pa r t and/or other compon ents not
specifically ap pr oved by Scotsman.

Scotsman reserves the right to make design
chang es and/or improvem ents at any time.

Specifications and design are subject to change
without notice.

CUT AWAY

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 cool e d m od el s i n a l ocation wh ere there is le ss
than 6" c learan ce to the left and right of the
cabinet.

CEILING

CUT AWAY

WALL

SPACE
ABOVE

FOR

SERVICE

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. Filt er th e w at er used to produ ce i c e . T ha t i s the
water go i ng to th e " potable" wat er c o nn ec t i on .
Water filters vary greatly in ability and function.
Install one that filters out suspended solids to a
dimension of 5 mi cr on s or sm al l e r . The f i ne r the
filter the better, but finer filters will clog sooner
than course ones. It may be necessary to add a
course filter ah ead of the fi ne filter to pr olong fi lter
life.

2. Chec k wi t h a w at er tr e atment spec ialist for a
water test, and recommendations regarding filters
and treat m en t.

6" SPACE

FOR AIR

(A/C)

Airflow

SPACE

FOR

UTILITIES

6" SPACE

FOR AIR

(AIR COOLED)

April 1997

Page 3

NDE550 & NDE650

FOR THE INSTALLER

Location

After uncrating and insp ection, the unit is ready for
installation. It is important that the machine be
install ed in a location where it has enough space
above an d be hi n d i t for service . Air c o ol e d m od el s
requi r e a minimum of 6 inches to the left an d right
of the machine for air circulation.

Machi ne Stand Installat ion

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-dis pe nser 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 coun te r top to m atch the outs i de edg e 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.

Follow the instructions packed with the machine
stand fo r pr op er c on ne ction to the di spenser.

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
assemb l y onto the two si nk bracket s , an d pr e s s
onto th e bead of sealant. Wipe off and neatly
smooth any excess sealant from un der the sink
edge.

SEAL TH E

UNIT TO

THE

COUNTER

OR STAND

April 1997

Page 4

NDE550 & NDE650

FOR THE INSTALLER: Wal l Mount Kit

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

install ation 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 w al l and of adequat e s tr e ng th to support
the weight of the machine when in use.

////// ///////////////////////////////////////////////////////////////////////
Clear an ce between the w all an d the icemake r is a

maximum of 1 inch. Check utility connections first.
The electrical junction box will have to be
removed, and the electrical connection s made
inside the cabinet in compliance with local codes.
The plu m bing conn ections may be made through
the base, or at either side through the pre-punched
holes , us ing standa r d pl u m bi n g pr actices.

Interi or pl u m bi n g l ine s m ust be discon ne cted from
the origi nal connections and plugg ed when routing
through the side or base.

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

X"

7.58"

1" CLEARANCE

BASE
HOLE

SIDE

ROUTING

X = 30" for NDE550

X = 38.6" for NDE650

16"

16"

A

DO NOT LIFT ON SINK

2. Mount brackets "B" and "C" to the wall at the
dimen sions shown for the unit. (hardware for this is
not inc luded).

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
aligne d an d s e cur e wi t h th e r em a i ni n g ( 2) 1/ 4- 2 0
bolts, flat washers and lock washers.

C

April 1997

Page 5

NDE550 & NDE650

FOR THE INSTALLER: Sod a Valve Kit

Installa t io n Ins t ru c tio ns

Note: C arbonator and carb onate d pr oduct cooling
system are not included (for 115v models only).

Electrical Shock Hazard.

Disconnect electrical
power to the icemaker ­dispenser before
beginning.

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

2. Remove water glass filler lever from machine.

3. Remov e w at er ou tl e t tu be f rom m achine.

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

5. Remove large pl ug from base of
icemaker-dispenser.

6. 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 carb onated lines.

7. Route product l ines through the hole in th e base.

8. Make all required connections soda line
connections, usi ng fi el d sup pl i e d m at er i a l s . All
lines should be insulated. A carbonated water
recirculating line is provided and recommended to
insure t ha t hi g h qu al i t y dri nks are dis pe nse d.

9. Install trans fo r m er i n up pe r com p ar tment of
icemaker-dispenser, using screws provided. It may
be necessary to pre-drill holes.

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

11. Conne c t wir e leads from th e dr i n k v alves to the
24 volt output side of the transforme r.

12. Locate a 115 volt continuous power source
from within the icemaker control box. Route white
and blac k l ea ds from the 11 5 vol t input sid e of the
trans fo r m er an d connect to th e 11 5 v olt power
source.

13. Turn on po w er an d so da equipment, check
operat i o n an d c h eck for leak s. Adjust valves for
proper m i xture.

115 VOL T
CONNECTION

ATTACH DRINK VALVE
ASSEMBLY HERE

TRANSFORMER

24 VOLTS

SODA VALVES

SODA
LINES

April 1997

Page 6

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, connec t 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 w at er fil t er of
some type will be useful. In areas where the water
is highl y c o nc e nt r ated with mi ne r al s t he wa te r
should be t est ed by a water treat ment special is t,
and the recommendations of the specialist
regard i ng fi l tr a ti o n an d/or treat m en t should be
followed.

Water Cooled Models: A separat e 3/ 8" O. D.
copper l i ne is r ecommend ed , w i th a se pa r ate hand
valve to con tr o l it . It is c o nn ected to a 3/8" FPT
conden s er i nl e t at the back of th e c a bi n et . T he
water pressure to all lines must always be above
20 psig, and below 80 psig.

NDE550 & NDE650

WATER INLET

CABINET

DRAIN

OPTIONAL

WATER

FILTER

Drains

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

at the bac k of th e c a bi n et , th e dr a i n li ne is of the
gravity type, and 1/4 inch per foot fall is an
acceptable pitch for the drain tubing. Ther e
should be a vent at the highest point of the drain
line, an d th e i de al dr a i n r ec eptacle wou l d be a
trapped and vented floor drai n. Use only 3/4" rigi d
tubing.

Water Cooled Models: In additi on t o th e ab ove
mentioned drain, a separate condenser drain must
be inst al led. Connect it to the 1/2" c on de nser drain
connection at the back of the cabinet.

WATER IN LET

SHUT OFF

VALVE

VENTED

DRAIN TUBE

FLOOR DRAIN

WATER COOLED D ETAIL

CONDENSER

WATER INLET

April 1997

Page 7

POTABLE

WATER INLET

CABINET

DRAIN

CONDENSER

DRAIN

NDE550 & NDE650

FOR THE ELECTRICIAN

CONFORM TO ALL APPLICABLE CODES

The electrical power to the unit is
suppl ied through th e j un cti o n box at the
rear of the machine.

Check the nameplate (located on the
back panel) for the v o l ta ge
requi r ements, and for the mi nimum
circuit ampacit y. The machine requires
a solid c ha s si s to earth gr ou nd wi r e .

The ice maker should be connected to
its own el e c tr ical circuit so it woul d be
individually fused. Voltage variation
must remain within design limitations,
even under starti ng conditions.

All external wiring mus t conform t o
nation al , state, and lo ca l el ectrical
codes. The use of a licensed
electrician is required to perform the
electr i ca l in s t al la t io n.

ELECTRIC AL

POWER

JUNCTION

BOX

April 1997

Page 8

NDE550 & NDE650

FOR THE INSTALLER: Final Check List

1. Is the icemaker-dispenser installed indoors, in a
location where the air and water tem peratures are
contro lled, and where th ey do not go beyond
design limitations?

BACK VIEW OF COMPLETED INSTALLATION

ELECTRICAL?

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 com pa r ed to na m ep l ate require m en ts ?

3. Have all of the plumbing co nnectio ns been
made and c h ec ked for lea k s?

4. Has the machine been leveled?

5. Is there a minimum of 6 inches of clearance at
the left an d r ight sides of an air c o ol e d m ach i ne ?

6. Is there a minimum of 6 inches of clearance at
the top an d ba ck of the machine for ser vice and
utility connections?

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?

LEVELED?

ICEMAKER

DISPENSER

PLUMBING?

8. Have all of the ship ping blocks been removed?

MACHINE

STAND

April 1997

Page 9

NDE550 & NDE650

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 al l packing tape (che ck 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 sequ ence 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 dischar ge warm water down the drain.

4. Inspect the interior of the machine for loose
screw s or w i r es. Ch eck that no re fr igerant lin es are
rubbi ng 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.

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

6. There ar e no adjus tments to mak e, so repla ce
the pane ls .

7. Check ice dispensing by pushing in on the glass
filler lever. Ice dispenses are portion controlled; by
turnin g a kn ob , the length of ti me th e unit
dispenses when the glass filler lever is pushed
(and the am o un t of ic e di s p en s e d) is adj u sted.

8. Switch off the icemaker-dispenser, remove the
top panel and th e top of the ice storag e bi n.
Sanitize the interior of the ice storage bin by wiping
it with a mixt ur e of 1 ounce of househ ol d bleac h to
2 gallon s of water, all o w to ai r dr y. Replace al l
covers and panels. Switch the icem aker-dispenser
back on .

5. The uni t s h ou l d soo n be making ic e. If de si r e d,
the low side pressure may be checked: it should
be 38 PSIG + or - 2 PSIG.

The air cooled discharge pressure will depend
upon air and water temperatures, but should be
between 240 PSIG and 340 PSIG.

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

9. Give the ow ne r /user the se r vi ce manual, ins tr u c t
him/her in the op er ation and maintenance
require m en ts of the unit. Ma k e su r e th ey k n ow
who to call for service.

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

April 1997

Page 10

COMPONENT DESCRIPTION

NDE550 & NDE650

Control Box: Conta ins th e el e c t r i cal controls th at

operate the machine.
High Pressure Cut Out Switch: A manual reset

switc h sensing the hi g h si d e r efrigeration press ur e .
It is set to shut the machine off if the discharge
pressure should ever exc eed 450 psig.

Evaporator: A vertical stainle ss steel tu be,
refrigerated, and water filled. In it there is a
stainless steel auger.

Reservoir: Float operated, it maintains the water
level i n th e ev a po r at or at a constant le vel, 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
machin e off it there is no ne .

Ice Level Sensor: An
electronic "eye", it senses the
presence of ice in the bottom of
the ice discharge chute.

ICE LEVEL SENSORS

Operates to turn the ice
machine on and off
automatically as the level of ice
in the bin changes.

Drain Tube: When uncapped
and lowe r ed , dr a i ns the
evapor a t o r .

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 sens ors,
and the ice making will stop.
Ice is dispensed through a
chute at the bottom f ront when
the bin vane sweeps the ice
over th e chu t e .

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

Portion Control Knob: Turning this knob adjusts
the length of time of di sp ense.

Note: Portion Control Optional after 4/97.

Low Pressure Cut Out Switch: A manual reset

control that shuts off the ice machine when the low
side pr e ss u r e dr o ps be l ow a pr e s e t po i nt, 0-4 psig.

WATER LEVEL

SENSOR

EVAPORATOR

RESERVOIR

CONTROL

BOX

DRAIN TUBE

HIGH PRESSUR E

CUT OUT

CONDENSER

LOW PRESSURE

CUT OUT

ICE STORAGE B IN

GLASS FILLER LEVER

PORTION

CONTROL

April 1997

Page 11

NDE550 & NDE650

COMPONENT DESCRIPTION

Evaporator: A refrigerated vertical tube filled with
water an d c o nt ai n i ng a wa te r se al and auger.

Auger: A solid sta i nl e ss st e el double spi r al au ge r ,
it push es th e i ce crystals up to th e to p of t he
evapor ator.

Water Seal : A two part "fa ce" seal , the top half
rotat ing with the au ge r , th e bo ttom half stationar y,
the sealing action being where the two seal "faces"
meet.

Ice Swee p : A plastic cap with "fingers". It revolves
with the auger to "sweep" the ice int o the ice chute.

Breaker: Where the ic e i s c ompressed and mu ch
of the extra water is squeezed out of it before it is
discha r ge d i nt o the bin.

Motor: A permanent split capacitor motor that
drives th e ge ar r ed ucer.

Thrust Bearing: As the ic e i s pu s he d 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

April 1997

Page 12

NDE550 & NDE650

COMPONENT DESCRIPTION: Control Box

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

Circuit Board: Controlling
the ice machine through
sensors and relays. The
senso r s ar e f or i c e l ev el and
water level. The relays are for
the gear motor (with a built in
time delay to clear the
evapor a to r of i c e when the
unit tur ns off) and for the
compressor.

On/Off Switch: Manual
control for the machine.

Transformer: Supplies low
voltage to the circuit board.

Potent ia l Rel ay : The
compressor start relay.

Portion Control Module:

Controls the amount of time
the dis pe nsi n g dr i ve motor is
on. The time is varied by
adjus ti n g th e po r ti o n c on tr o l
knob. Optional after 4/97.

POTENTIAL

RELAY

TRANSFORMER

ON-OFF SWITCH

CIRCUIT

BOARD

PORTION

CONTROL MODULE
(Optional After 4/97)

CONTACTOR

April 1997

Page 13

NDE550 & NDE650

ELECTRICAL SEQUENCE

Refer the wiring diagram as needed.

If the machine is switched off at the master switch,
but is ot he r w i se r ea dy to go, switching the m aster
switch to on does the following:

The bin em pty light on the circuit board goes on

•

There is a 15 sec o nd del a y

•

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 m ot or starts, an d th e ce ntrifuga l

•

switch closes, connecting power to the
compressor contactor coil.

The cont actor is ener gized, 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

•

more minutes, clearing out ice in the
evapor a to r , and then

The auger m otor relay op en s , 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.

Anothe r pur p ose of the circuit boar d is to tu r n th e
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"

When the water refills the reservoir, the

•

machine will start up again.

Separate from the circuit board:

If the high pressure control (cut out sw i tch)

•

opens, the machine will stop immediately
(through the relays on the circuit board). It must
be manually reset.

If the low pressure control (cut out switch)

•

opens, the machine will stop immediately
(through the relays on the circuit board). It must
be manual ly reset .

The mast er s w it c h i s t he ma nu al co ntrol 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 a circuit to the bin drive motor.
Dispensing continues until the lever is released.

If ther e is an opt i on al po r t ion control , ho l di n g

•

the glass filler lever in will not cause additional
dispe ns i ng . R el e asi n g and re-pus hi n g th e gl a s s
filler lever will repeat the dispense cycle. The
portion control may be set to continuous.

April 1997

Page 14

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 wa ter then goes out
the bottom of the reservoir tank to the bottom of
the evap or a tor.

Reservoir overf low, evaporator condensation and
water in the sink are all routed to the drain. Water
cooled models have a separate water circuit fo r
the cooli n g w at er : it ent er s th e fitting at the re ar ,
goes to the water regulating valve, then to the
water c o ol e d c on de nser and dow n the drain.

There is al so an ad di tional wat er c ir c u i t to an
electric valve. When the water station glass filler
lever is pushed, a switch closes a circuit to the
elect r i c wa te r val ve, and water i s di spensed.

NDE550 & NDE650

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

1

" above and

⁄

8

1

" below the line.

⁄

4

float arm.

WATER RESER VOIR

WATER INLET

WATER DRAIN

WATER

LEVEL

WATER LINE FOR

WATER STATION

April 1997

Page 15

NDE550 & NDE650

OPERATION: Refr igeration

Beginni n g at the compr es s or , the refrig er ant is
compressed int o a high temper at ur e gas. The
disch ar ge line directs th i s gas to the co ndenser . At
the cond en s er ( air or w at er cooled) th e ga s is
cooled by either air or water and it then condens es
into a li qu i d. Th is hi g h pr e ss u r e l iquid then goe s
through the liquid line to the expansion val ve.

The ther m ostatic expansio n va l v e m et er s liquid
refri ge r an t i nt o the evapora t o r , th e vol u m e of liquid
refrigerant depending upon the temperature of the
evaporator; warmer evaporators get more
refrigerant and colder evaporators get less.

REFRIGE R A TION

SCHEMATIC

At the evaporator, the refrigerant enters an area of
relatively low pressure, where it can easily "boil
off" or ev a po r at e. As it evapo r at es, 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 , go es th r ou gh the s uction line ba c k to
compressor, where the cycle is repeated.

SUCTION LINE

LIQUID LIN E

CONDENSER

DISCHARGE

LINE

COMPRESSO R

EVAPORATOR

THERMOSTA T IC

EXPANSION VALVE

April 1997

Page 16

OPERATION: Ice Vending

When the i c e dispensing gl a s s
filler lever is pushed, an electrical
circuit is made to the portion
control module in the control box.
That module will energize the
dispense drive motor for a certain
length of time, depending upon the
setting of the portion control knob.

The dispensing takes place when
the dispensing vane sweeps the
ice over the ice dispensing chute:
ice will continue to discharge out
this chute as long as the vane is
turning. It stops when the
dispensing vane stops.

NDE550 & NDE650

Ice Dispensing

Vane

VEND SWITCH

GLASS FILLER

LEVER

BIN BOTTOM

ICE CHUTE

DRIVE MOTOR

SINK

April 1997

Page 17

NDE550 & NDE650

CLEANING and SANITIZING

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 RESPONSIBILI TY t o 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.

Sanitizing of the ice storage bin should be scheduled for a

Electrical power will be ON when doing in place cleaning.
ICEMAKING SYSTEM: In plac e cleaning

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

2. Remove screws and re m ov e th e upper fron t
panel.

3. Move the ON-O FF 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 att ached 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 Scots m a n Ice Machine Cle aner with thr e e
quart s of hot water. The wa te r sh ou l d be bet w ee n
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 im mediately. In
case of external contact,
flush with water. Keep out
of the reach of children.

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

9. As the i ce m aker begin s to use water fr o m 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 , sw i tch the master sw i t ch to O FF .

11. After draining the reservoir, as in step 6, wash
and rinse the water res e r voir.

To Sanitize:

Repeat steps 8-11, only use an approved
sanit i zi ng s olution in pla ce of the cleani ng
solut i on . A po s si b l e san i ti zing solut i on to use could
be 1 ounce of household bleach mixed with 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 i ce making for at least 15 minutes, to
flush ou t any cleaning solution. Check ice for ac id
taste - continue ice m aki n g until ice t ast es 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 war m w at er to the ice storage bi n and
thoroug hl y wash and ri ns e al l sur faces within the
bin.

17. Sanitize the bin cover, dispensing vane, bin
botto m , and interior with an approved sanit i zer
using the directions for that sanitizer.

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

minimum of 4 times a year.

o

F. - 115oF.) water.

April 1997

Page 18

MAINTENANCE AND CLEANING

Moving Parts Hazard.

Disconnect electrical
power to the icemaker ­dispenser before
beginning.

1. Air Cooled Models: Check the air cooled
condenser for lint, dirt or grease build-up. Clean
with vacuum or soft brush until light can be seen
thru the fins.

NDE550 & NDE650

Slide UP To

Remove

Reservoir

BIN CONTROL

SENSOR

2. The ice machine s e nses water l ev e l by a pr obe
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.

3. 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.

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

A. Check the bearing by:

removi n g the ice chut e cover

•

BIN CONTROL

SENSOR

BIN TOP

CLEAN WATER

SENSOR PROBE

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

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

Inspect the assembly, looking for wear.

ICE SWEEP

unscrewing the ic e s weep

•

removing the water shed

•

unscrewing the breaker cover.

•

unscrewing the auger stud

•

See Removal and Replacement to replace
bearin g or seals. Reverse to reas s em b l e.

5. Check and tighten all bolts and screws.

April 1997

Page 19

NDE550 & NDE650

MAINTENANCE AND CLEANING

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

Moving Parts Hazard.

Disconnect electrical
power to the icemaker ­dispenser before
beginning.

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 r em o v ed so the parts ca n
be inspected.

Note: Water filters can filter out suspended solids,
but not dissolved sol i ds. "Soft" w at er m ay no t be
the complete answer. Check with a water
treatm en t s p eci a l i st re ga r di n g w at er 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. Push bail clamp off of cover and remove cover.

3. Unscrew and remove ice sweep.

4. 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. Repl ace the wat er seal.

8. Reverse to reassemble.

ALLEN

HEAD

SCREWS

BREAKER

AND AUGER

ASSEMBLY

April 1997

Page 20

NDE550 & NDE650

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

STATUS:

Check:

A.

Check: The

B.

Check: The

C.

machine still does not start, check the high and the low s ide pressures.

Check the

D.

Low refrigerant charge

•

The auger not turn ing

•

Restricted system

•

TXV not opening

•

1. Check the low si de pressur e, the low pressur e cut out opens at pre ss ure below 4 psig.
If open , r eset and:

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

repla ce it. Replace the drier, evac uate, an d weigh in the namep late cha r ge.

ICE MAKER DOES NOT OPERATE

Voltage

low pressure cut out,

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

b. Check for low charge, add some refrigerant, if the unit will operate, (normal
low side pressure being about 38-40 psig) stop and look for a leak, repair, replace the

does not operate:

to the unit, restore power if there is none. Compare to the nameplate.

master switch
reset swi tc h e s

Check for internal damage, repair an d replace in the mac hine.

Check for a restricted system, replace the drier, evacuate, and weigh in a
nameplate charge.
Check for a The rmos tati c Expansion Valve that does not open, if defective,

, switch ON if off.

, (high and low pressure): depress and release each switch. If the

if closed, go to

if it is open, it coul d be due to

E;

:

Check the

E.

1. The pressure control opens at 450 psig. Check the high side pressure, reset the control,
and obse r ve: on wate r cooled, that water soon be gins 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 45 0 psig, repl a c e th e control. If th e pr e s su r es ri s e abo ve th e tr i p out
point, an d th e un i t s hu ts down:

filter. If th e ai r fl o w is po or because of th e i nstallat ion, advise the user th at the unit
should be moved, or the air around it kept cooler.

. Check the

F

reservoir.

high pressure cut out,

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 co oled. Clean the condenser and (if us ed) the

Check the fan motor for tight bearings and proper rotation.
Check that the fan blade s are clean, and the fan secur e to the fan motor s haft.

water level

1. Resto r e/ adjust wat er l eve l . See the next step.

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

if closed, go to F; if open:

April 1997

Page 21

NDE550 & NDE650

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

STATUS:

. Chec k : The gear

H

Check: The indicator lights on the circuit board, the bin empty light shoul d be ON, the no water light
shoul d be OF F .

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

side should have between 110-120 volts (60 cycle units). If the line side has the correct voltage
the load s ide does not, repl a c e the transfor m er .

2. If the tr ansfor m er is good, and the bin empty light is OFF, check the ice le vel sensors.

Tester M od el N M 1 into the circuit board .

3. If the tr a nsf or m e r is fi ne , an d the "no water" li gh t i s ON , c h eck the water level sensor.

ICE MAKER DOES NOT OPERATE

motor

a. Transformer "load" side should have 12 to 15 vo lts. If not, check the "line " si de. The line

a. Remove sensors by pulling them out of the ice chute grommets. Visually inspect them,
clean if ne ed ed.
b. Look thr ough the ic e chute "eye" hole for somet hing blo ck ing 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. Unplu g "o pt o tr a ns" and "LED " co nn ec t or s from the ci r cuit board.

2. Plug "opto trans" and "L ED" connectors fr om the Scotsman Electronic Control

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.

, if it will not run, the compressor will not run. If no power to it:

a. Move the "bin full" switch on the tester to the full position. The bin full light
on the tester should be ON, if no t, 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. Move th e w at er sw i t c h on the t es ter to "no water " an d the no water li g ht
on the c i rcuit 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

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

April 1997

Page 22

NDE550 & NDE650

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

STATUS:

Check the

A.

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 po w er at the co nt actor coil , i f no ne :

2. Che ck the contactor c o il. If the coil is open, repl ace the contactor.

3. Check the auger drive motor centr i fugal swi tch. If, when the drive motor is running,
contac t 4 (b l ac k wi r e re m oved) has no power, and all of the above switches hav e be en
checked, replace the centrifugal switch, or the drive motor.

4. If the com p r essor rela y on the circui t board has pow e r on th e N O contact, bu t no t on the COM con tact,

replace the circu i t bo ar d .

B. Check the compress or

1. Check the compressor start relay.

2. Check the start capacitor.

3. Check the wind ings of th e compres sor for open windings or shorts to groun d.
Replace those items found defective.

GEARMOTOR OPERATES, COMPRESSOR DOES NOT

compressor relay.

a. Chec k 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 ope n wire between the relay and the contactor.

April 1997

Page 23

NDE550 & NDE650

SERVICE DIAGNOSIS: Condition - Low Ice Production

STATUS:

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

A.

cooled. Adjust as required. If the head pre s s ure is very high:

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

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

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

nameplate.

Check the evaporator

B.

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

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

3. Check the low side pressure; normal is about 38 psig. If low, assume a refrigerant leak,
locate, repair and recharge.

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
of foam tape to the evaporator.

EVERYTHING IS OPERATING

If no leak, the TXV may be restricted, defective or not adjusted properly. If needed,
replace the TXV, evacuate, and recharge per nameplate.

Check the compres sor.

C.

1. The compressor may be inefficient.
a. Check the amp draw, if low change 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
there for three to five minutes.

April 1997

Page 24

NDE550 & NDE650

SERVICE DIAGNOSIS: Condition - Poor or No Ice Di spensing

STATUS:

Check for ice in the b in. If no ice, check the ic e m aking syst em .

A.

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

machine may be needed.

. Check for motion in the agitator when the glass filler lever is pushed, if no motion: Check the vend

B

switch, if it does not close when the glass filler lever pushes in the actuator button, replace the switch.

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

replace the portion control module in the control box. If there is voltage, and the agitator
motor output shaft does not turn, replace the agitator gear motor assembly.

. No por tion contro l ( portion control opti onal after 4/97)

C

There is power to the unit, but no ice dispensed

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.

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,
replace it.

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

April 1997

Page 25

NDE550 & NDE650

REMOVAL AND REPLACEMENT

WATER RESERVOIR

1. Shut of f th e w at er su pply to the ice m ake r .

2. Remove front panel and reservoir cover.

3. Disconnect inlet water line from valve.

4. To remove jus t the float, push the lockin g tab at
the back of the valve mo un ti n g bl o ck i n an d li ft the
valve and block up and out of the reservoir tank.

Note: inside the valve, there is a plunger which
may be replaced separately, if desired.

5. To remove reservoir, remove drain hose from
reservoir.

6. Remove evaporator inlet ho s e fr om r ese r v o i r .

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 pa nel.

3. Remove control box cover.

4. Locat e bi n t op , i n fr o nt of and behind it ar e two
rubber bin control grommets.

5. Pull ea c h bi n con tr ol out, and i n th e co ntrol box,
disconnect the electrical leads connecting the bin
control to the circuit bo ard.

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

BIN CONTROLS

FLOAT VALVE

VALVE

PLUNGER

LOCKING TAB

GROMMETS

BIN TOP

April 1997

Page 26

NDE550 & NDE650

REMOVAL AND REPLACEMENT: Bearing And Breaker

Note: Removal of the auger, water seal,
evapo r ator and gearmotor must begi n at the to p of
the assem b l y .

Moving Parts Hazard.

Disconnect electrical
power to the icemaker ­dispenser before
beginning.

To Remove the Breaker Bearing Assembly:

1. Remove panels and disconnect electrical power.

2. Move bail clamp ba ck 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 bre aker may be re m ov ed f r om 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. Unsc rew 4 al l e n he ad ca p sc r e w s ho l di n g
breake r to evaporator.

d. Lift up , an d r em o ve breaker/ be ar i n g assembly
from auger & evaporator.

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

a. The bear ing is pressed into the break er, to
remove the bearing and replace it an arbor press
is need ed .

b. Replace lower seals before installing new
bearin g i n br e aker.

Note: seals must be pressed in with a tool pushing
against the outer edge only, they will not install by
hand.

Replac e parts as re qu i red. Re-grea s e be ar i n g w it h
Scotsman part no. 19-0609-01 bearing grease.
Replac e top seal, and c h eck the o-ri ng s, r eplace if
cut or torn.

7. Reverse to reassemble: specific tools and
materi a l s ar e re qu i r ed t o ins t al l pr o perly.

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

b. Check the seal to shaft ar eas for cu ts, or rough
spots: none are permitted.

Steps 3 - 5a Step 5 b Steps 5c - 6

ICE

SWEEP

AUGER

STUD

BREAKER

BEARING

BREAKER

April 1997

Page 27

NDE550 & NDE650

REMOVAL AND REPLACEMENT

To Remove the Auger:

Turn off the wat er to the ma chine, and unclip the
evapor ator 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/be ar ing may now be
removed as an assem bl y.

a. Unscrew 4 allen head cap screws holding
breake r to evaporator.

b. Lift up on br e aker and rem o v e au ge r f r om
evapor a t o r .

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

The bre a ker may be re moved from the auge r and
evaporator without disturbing the auger.

a. Unscrew breaker cover from breaker (left hand
threads)

b. Unscrew auger stud from top of auger.
c. Unsc rew 4 al l e n he ad ca p sc r e w s ho l di n g

breake r to evaporator.

d. Lift up & re m ove breake r fr om evaporato r .
e. If the auger is stuck use a slide hammer type

pulle r to pull on the auger a t the threaded hol e.
The siz e of t ha t ho l e i s 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.

////// // // // // // // // ///////WA R NIN G // // // // // // // // ////////// ////
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. Remo ve the water seal top half from the
auger, and inspec t th e au ge r for m i ne r al s clean as
required.

SLIDE HAMMER

PULLER

BREAKER

AND AUGER

ASSEMBLY

April 1997

Page 28

NDE550 & NDE650

REMOVAL AND REPLACEMENT: Water Seal

To Remove the Water Seal:

(Assum i n g al l s t ep s to r em o v e the auger hav e
been performed.)

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

2. Remove the 4 hex head c a p s cr e w s hol d i ng the
evapor a to r t o th e ge ar m o to r ass e m bl y. Lift the
evapor a to r up an d off of the gea r motor.

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

4. Pull or dr ive out the low e r hal f of the water sea l .

To Replace the Wate r Seal:

1. Lubricate the w ater sea l with water, and push
the water s e al into the bottom of the evaporator
slightly past the grove for the snap ring.

3. The part of the water seal that rotates with the
auger mu s t al so be re pl a c e d. Rem o ve the old part
from the auger and clean the m ounting area.

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

5. Carefully push the water seal (rubber side
agains t the auger should er an d th e s il a s ti c.)

WATER

SEAL

RETAINING

RING

2. Replace the snap ring and pull the water seal
down agai n s t it.

FOOD GRADE

SILASTIC

SEALANT

HERE

////// // // // // // // // /////////C A UT IO N// ////////////////// ///////
Do not get an y s i lastic onto the f ac e of t he seal .
////// // // // // ////////////////// ////////////////////////// ///////////////

6. Allow the auger and seal to air dry until the
silastic 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.

April 1997

Page 29

NDE550 & NDE650

REMOVAL AND REPLACEMENT

To Replace the Evaporator:

(Assum i n g al l th e steps for rem o v a l of th e th r ust
bearin g, breake r , au ge r , an d w at er s ea l have been
performed.)

1. Discharge the refrigerant from the ice maker.

2. Unsweat the refrigerant connections:
a) At the thermostati c 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 l iquid 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 le ak s .

8. Instal l auger, br eaker , br eaker be aring
assembly, and ice discharge chute in reverse
order of disassembly.

To Reassemble the Evaporator and Auger

1. After the gearmotor has been inspected, fasten
the evap or a to r to th e ge ar m ot or , be sure that th e
number of s h i m s in di c ated 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.

For Access to the Evaporator to
Gearmotor bolts :

1. Remove upper front and top
panels.

2. Remove screws holding cont rol
box ass em b l y to the cabinet , mov e
the cont r ol bo x out of th e w ay,
temporarily secure to cabinet.

3. Remove the upper half of the ice
chute.

4. Remove the ice sweep.

5. Loosen clamp un der ice chute,
and remo v e the lo w er half of the ice
chute.

6. Remove the 2 screws securing
the front portion of the gearmotor
suppor t to the cabinet

7. Move the the gearmotor ­evaporator to the right: space is now
available for r em o val of the
evapo r ator and gearmotor bolts.
When reassembling, reverse the
above s te ps.

MOVE THE

GEARMOTOR -

EVAPORATOR

CONTROL

BOX

SCREWS

April 1997

Page 30

NDE550 & NDE650

TO REMOVE AND REPAIR THE GEARMOTOR ASSEMBLY

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

Electrical Shock Hazard.

Disconnect electrical
power to the icemaker ­dispenser before
beginning.

1. Remove the el ectr ical 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 dr ive motor attached) up
and away from the gear m o tor 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 li kely
to be fine if the oil is.

GEARCASE

COVER

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.

ROTOR

BEARING

FIRST GEAR &

BEARINGS

GASKET

April 1997

Page 31

NDE550 & NDE650

REFRIGERATION SERVICE: R-404A (HP62)

THIS ICE MACHINE USES HP62 REFRIGERANT
AND POLYOLESTER COMPRESSOR OIL.

DO NOT USE MINERAL OIL IN THIS
REFRIGERATION SYSTEM.

HP62 is a "Near Azeotrope", and therefore

•

liquid charging is required.

Weigh i nt o th e di scharge sid e as much as possible
of the char ge as liquid refrigerant.

Install a sight glass between the manifold and ths
suction side hose. Carefully meter liquid refrigerant
into the suction side, using the manifold valve to
"flash of f" th e l i qu i d be fo r e it en te r s the ic e
machine. Do this until the proper charge has been
weighed into the system.

When the system is serviced, a special liquid

•

line dryer is required.
Polyolester oil absorbs water very easily, and

•

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

Special leak detection equipment is required to

•

locate small refrigerant leaks. Usually a leak
detect or c a pa bl e of detecting a H al o ge na ted
refrigerant or HFC-134A will work. Check with
the leak detector manufacturer if in doubt.

As with any other refrigerant, do NOT mix HP62

•

with pressurized air when leak testing.
The vacu um pu m p or r ecovery un i t sho ul d us e

•

polyolester oil. Evacuate to 300 microns.

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

-20 17 70 146

-18 18 72 150

-16 20 74 155

-14 21 76 161

-12 23 78 166

-10 24 80 171

-8 26 82 177

-6 28 84 182

-4 29 86 188

-2 31 88 194
033 90 200
235 92 206
437 94 212
639 96 219
841 98 225
10 43 100 232
12 46 102 239
14 48 104 246
16 50 106 253
18 53 108 260
20 55 110 268
22 58 112 275
24 60 114 283
26 63 116 291
28 66 118 299
30 69 120 307
32 72 122 316
34 75 124 324
36 78 126 333
38 81 128 342
40 85 130 351
42 88 132 360
44 91 134 370
46 95 136 379
48 99 138 389
50 102 140 399
52 106 142 409
54 110 144 420
56 114 146 430
58 118 148 441

Pressure-Temperature Chart for HP62

April 1997

Page 32

REFRIGERATION SERVICE

NDE550 & NDE650

General Information:

Work on t he re fr igeratio n sy s tem should on l y be
done when it is certain that the system needs
repair.

Refrain from checking refrigeration

•

pressures without reason. Visual inspection
of the water system, observation of the ice
formation, amp dr aw, voltage, and other
techniques will lead to proper diagnosis.
Scots m a n al so re c o m m en ds th at, at the tim e of
initial start up, gauges not be used.

If gauges must be used, don’t always check the

•

high sid e pr e s sure. If the c o nd en s er is cl ea n
and see m s to be operating corr ectly, i t mo st
likely is. The low side pressure is more
important on an ice machine than the high side.

If gaug es must be used, use ver y short hoses to

•

mini mi z e r ef r i ge r an t di s c ha r ge d i nt o th e ai r .
Refrigerant should not be added except as a

•

way to de te r m i ne the pr op er op er a t ion of the
produc t . If the syst em w as l ow on refriger a nt,
there i s a leak, and it must be found and
repai r ed.

This system has a cri tical cha rge, it must be

•

recharged with the correct amount of refrigerant
as listed on the name plate of the ice mach ine,
or performance will suffer.

Anytime the refrigeration system has been

•

opened, the dryer should be replaced. Note:
Only a HFC type dryer should be used.

Recover, reclaim or recycle refriger ant. The

method chosen is up to the service com pany. Any
refrigerant placed into a Scotsman ice machine
must meet ARI spec 700. Reclaim programs are
available through most refrigerant wholesalers.

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 t he va lve and repla ce th e caps w hen t he
job is finished. The valve must be closed and
the caps must be on or the valve will leak.

Allen

Wrench

Torque Stem to

6-8 ft. lb.

Torque Stem Cap to

8-12 ft. lb.

Torque

Core Cap to

7-12 ft. lb.

Access Valves

Note: There are no valve

cores in this valve.

When brazing the tubing connections to

•

components such as the TXV, the component
must be pr ot ected by heat s ink m at er i a l .

April 1997

Page 33

NDE550 & NDE650

TESTING ELECTRONIC CIRCUIT

INSTRUCTIONS FOR USING TESTER

(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.)

Electrical Shock Hazard.

Disconnect electrical
power to the icemaker ­dispenser before
connecting tester.

Bin Control

Note: All testing is done with the
elect r i cal po w er on , th e m aster swit c h on, and all
reset switches "reset" .

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

2. Plug "photo trans" and "LED" connectors from
the test er i nt o th e ci r cuit board.

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

The light on the tester should be ON.

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

If the li ght on the tester is not on, th e ci r cuit board
shoul d be re pl a c ed .

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”

April 1997

Page 34

TESTING ELECTRONIC CIRCUIT

NDE550 & NDE650

Water Level

1. Unplu g " water sen" connector from c ontrol
board.

2. Plug "w at er s en " conn ector from Scotsman
tester into circui t bo ar d .

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
shoul d go OF F. I f no t r ep l ace t he ci r cui t board. If
the ligh t do es go off, repl a c e th e w at er l evel sensor .

LIGHT OFF

SWITCH TO

“NO WATER”

SWITCH TO

“WATER”

April 1997

Page 35