Scotsman NME650R User Manual

INTRODUCTION

NME650R

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 system.

The NME650R is a remote condenser modular ice
system that fits a variety of Scotsman storage bins.
It features: front service for the freezer, gearmotor,
control box, water reservoir, and bin control; an
electronic circuit for monitoring ice and water level;
a thermostatic expansion valve; and HP62 as the
refrigerant.

Table of Contents

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

FOR THE INSTALLER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

REMOTE CONDENSER SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

FOR THE INSTALLER: Remote Condenser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

FOR THE PLUMBER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

FOR THE ELECTRICIAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

FOR THE INSTALLER: Completed Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

START UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

COMPONENT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

ELECTRICAL SEQUENCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

OPERATION: Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

OPERATION: Refrigeration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

CLEANING & SANITIZING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

MAINTENANCE AND CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

OPERATING CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

SERVICE DIAGNOSIS: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

REMOVAL AND REPLACEMENT: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

REFRIGERATION SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

CIRCUIT BOARD TESTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

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

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

Note this symbol when it appears.

August 1993

Page 1

It is an alert for important safety

information on a potential hazard.

NME650R

FOR THE INSTALLER

The NME650R is designed to fit the following
Scotsman storage bins:

••BH550 using bin top KBT14 or KBT20

••B90 with bin top KBT18.

••BH800 using bin top KBT15 (one unit).

••BH800 if using two units, no bin top needed.

••BH900 using bin top KBT24

When installing a new system, check to be sure
that you have everything you need before
beginning:

••Correct Bin

••Correct Ice Machine

••Correct Bin Top

••All kits, legs, and information required for the

specific job.

SPECIFICATIONS: ICEMAKER

Model Dimensions

W" x D" x H"

NME650RE-1A 21" x 24" x 27" 115/60/1 Nugget R-404a 208 ounces 35 22.5
* Minimum Circuit Ampacity is used to determine wire size and type per National Electric Code.
The Standard Finish is Enamel - Sandalwood. There is an optional stainless steel panel kit, SPKFM21
available to convert the unit to Stainless Steel. It is field installed.

Basic
Electrical

Ice Type Refrigerant

Type

June 1994

Page 2

Refrigerant
Charge

Max. Fuse
Size

Min..
Circuit
Ampacity

FOR THE INSTALLER

NME650R

Installation Limitations:

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

Min. Max.

0

Air Temperature 50
(Not including the remote condenser)
Water Temperature 40
Water Pressure 20 PSIG 80 PSIG
Voltage -5% +10%
(Compared to the nameplate)

Operating the machine outside of the limitations is
misuse and can 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.

F 1000F

0

F 1000F

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
around it to be accessible for service, usually a
minimum of 6 inches. Try to avoid hot, dirty and
crowded locations. Be sure that the location for the
machine is within the limitations described.

Storage Bin

Tip the storage bin on its back, using parts of the
carton to protect the exterior finish. Install the legs
into the threaded holes in the bottom of the bin.
Turn the leg levelers all the way in preparation for
leveling later. Return the bin to the upright position,
remove paper covering the bin gasket.

Install the bin top according to the directions with
the bin top.

Note: Do not push bin into position, but lift it there.
Pushing a bin, especially one with ice in it, can
cause damage to the legs and the leg mounts.

Ice Maker

The machine is heavy, so the use of a mechanical
lift is recommended for lifting the machine high
enough to install on top of the bin. After the unit is
placed on the bin, line it up so it is even with the
back side. Secure the machine to the bin with the
hardware provided with the machine.

Remove the front panel and remove any shipping
blocks.

Note: Be sure to allow a 6" minimum space
above the top of the machine for service.

August 1993

Page 3

19 7⁄8"

ERC DIMENSIONS

Model A B F G
ERC101

33 3⁄8" 10 3⁄4" 16 3⁄4" 11 5⁄8"

NME650R

REMOTE CONDENSER SPECIFICATIONS

23 13⁄16"

Model Use with Basic Electrical
RCE501-1 1 NME650R 115/60/1
ERC101-1 SAME 115/60/1

RTE25 Precharged line set, 25’, R-404A
RTE40. Precharged line set, 40’, R-404A

ICEMAKER NAMEPLATE

LOCATED ON BACK PANEL

SERIAL PLATE LOCAT ED

BEHIND FRONT PANEL

June 1995

Page 4

FOR THE INSTALLER: Remote Condenser

REMOTE CONDENSER

SPIRAL

EXCESS

TUBING

INSIDE

BUILDING

NME650R

Location

Limited to a 40 foot or a 25 foot length of
precharged refrigerant tubing connecting the
icemaker to the remote condenser. The
condenser must be above or level with the
icemaker.

Select the best available location, protecting the
condenser from extremes of dirt, dust, and sun.

Meet all applicable building codes. Usually the
services of a licensed electrician are required.

Roof Attachment

1. Install and attach the remote condenser to the
roof of the building, using the methods and
practices of construction that conform to the local
building codes, including having a roofing
contractor secure the condenser to the roof.

2. Have an electrician connect the remote
condenser fan motor to the icemaker, using the
junction box at the back of the icemaker.

PRECHARGED LINE ROUTING

///////////////////////////////CAUTION////////////////////////////////
Do not connect precharged tubing until all routing

and forming of the tubing is complete. See the
coupling instructions for connecting information.

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

1. Each set of precharged refrigerant lines (either
25 foot or 40 foot) consists of a 3/8 inch diameter
liquid line and a 1/2 inch diameter discharge line.
Both ends of each line have quick connect
couplings, one end has a schrader valve
connection, that end goes to the condenser.

Note: The openings in the building ceiling or wall,
listed in the next step, are the minimum sizes
recommended for passing the refrigerant lines
through.

2. Have the roofing contractor cut a minimum hole
for the refrigerant lines of 1 3/4 inch. Check local
codes, a separate hole may be required for the
electrical power to the condenser.

///////////////////////////////CAUTION////////////////////////////////
DO NOT KINK OR CRIMP REFRIGERANT

TUBING WHEN INSTALLING IT.
///////////////////////////////////////////////////////////////////////////////

3. Route the refrigerant lines through the roof
opening.

Follow straight line routing whenever possible.
Any excess tubing MUST be retained within the

building.

4. Spiral the excess length of pre charged tubing
inside the building. Use a horizontal spiral (need
not be as tight as illustrated) to avoid any traps in
the lines.

5. Have the roofing contractor seal the holes in
the roof per local codes.

LOCATE REMOTE

CONDENSER

ABOVE ICEMAKER

August 1993

Page 5

NME650R

FOR THE INSTALLER: Coupling Instructions

////////////////////////////////CAUTION////////////////////////////////
The couplings on the sets of precharged lines are

self sealing when installed properly. Carefully
follow the instructions:

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

Initial Connections

1. Remove the protector caps and plugs. Wipe the
seats and threaded surfaces with a clean cloth to
be certain that no foreign matter remains on them.

2. Lubricate the inside of the couplings, especially
the O-Rings with refrigerant oil.

••The 1/2 inch discharge line (schrader valve

end) goes to the remote condenser fitting
marked "discharge line"

••The 3/8 inch liquid line (schrader valve end)

goes to the remote condenser fitting marked
"liquid line".

••The 1/2 inch discharge line connects to the

icemaker fitting marked "discharge line".

••The 3/8 inch liquid line connects to the

icemaker fitting marked "liquid line."

Final Connections

3. Begin tightening the couplings together by
hand, then using two wrenches (it is important that
ONLY the nut on the precharged lines be turned,
the other parts of the couplings must NOT be
allowed to turn or the process will tear out the
diaphragms and they will be loose in the
refrigeration system) tighten the coupling until it
bottoms out or a definite increase in resistance is
felt.

4. Using a marker or pen, mark a line lengthwise
from the coupling union nut to the bulkhead. Then
tighten the coupling and additional 1/4 turn. As the
nut turns, the line will show when 1/4 turn is made.

5. After all connections are made, and after the
king valve has been opened, check the couplings
for leaks.

Note: The system charge is contained in the
receiver tank of the ice machine. Only "holding"
charges are present in the "pre-charged" tubing or
the condenser.

The RCE501-1A is a single circuit, 115 volt, 1 ton
condenser.

SERVICE PORTS

REMOTE CONDENSER

3/8" LIQUID LINE

1/2" DISCHARGE

LINE

SCHRADER

VALVE

TO REMOTE

CONDENSER

NO SCHRADER

VALVE

TO ICEMAKER

June 1994

Page 6

FOR THE INSTALLER: Location

ICEMAKER

TYPICAL INSTALLATION

EXCESS

PRECHARGED

TUBING INSIDE

BUILDING

NME650R

REMOTE

CONDENSER

ROOF

CUTAWAY

SERVICE

ACCESS

SERVICE ACCESS

SIDE AND BACK

WALL

CUTAWAY

August 1993

Page 7

FIELD

SUPPLIED

WATER FILTER

NME650R

FOR THE PLUMBER

CONFORM TO ALL APPLICABLE CODES

Water Inlet

HAND SHUT

OFF VALVE

CONNECT TO

COLD WATER

WATER INLET

3/8" MALE

FLARE

VENT

ICEMAKER

DRAIN,

3/4" FPT

The recommended water supply is
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.

Drains

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.

Storage Bin: A separate gravity type
drain needs to be run. Insulation of
this drain line is recommended.

VENT BIN DRAIN

3/4" FPT

FLOOR DRAIN

June 1994

Page 8

FOR THE ELECTRICIAN

CONFORM TO ALL APPLICABLE CODES

NME650R

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.

Electrically the remote condenser fan motor is
connected to the icemaker at the contactor

TERMINAL STRIP

FOR REMOTE

CONDENSER

ICEMAKER

JUNCTION BOX

terminals for the compressor and the fan motor
operates whenever the compressor operates.

Electrical connections are made at the junction
box at the back of the icemaker and at the junction
box on the remote condenser.

The remote condenser must be wired to the
icemaker in accordance with local and national
electrical codes with a minimum of 18 Awg. wire
with an ground bonding wire connected to the
ground screws provided in both the condenser and
machine field wiring boxes. All outdoor wiring
must be in rainproof conduit.

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.

GROUND

THE

CHASSIS

POWER

SUPPLY

RAIN PROOF

CONDUIT

August 1993

Page 9

INSULATED
PRECHARGED
REFRIGERANT

TUBING

NME650R

FOR THE INSTALLER: Completed Installation

A typical installation should generally appear as
illustrated below. The remote condenser must be
located above the icemaker and the precharged
lines installed per the instructions on page 6.

ROOF

CUT-AWAY

June 1994

Page 10

FOR THE INSTALLER: Final Check List

1. Is the ice system installed
indoors in a location where the
air and water temperatures are
controlled, and where they do
not exceed the design
limitations?

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

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

4. Has the machine and bin been
leveled?

5. Is there a minimum of 6"
clearance at the rear, left, and
right of the machine for proper
service access and air
circulation?

6. Is the water pressure a
minimum of 20 psig?

7. Has the machine been
secured to the bin?

8. If two units on one condenser,
has the relay kit been installed?

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

10. Is the remote condenser
installed per local building codes,
and in a place where it has
adequate ventilation and minimal
solar heat gain?

11. Has all shipping material and
literature (inside the front panel)
been removed from the units?

12. Have the remote condenser
and precharged lines been
properly installed?

13. Has the electrical connection
between the icemaker and the
condenser been made?

14. Verify that the master switch is in the OFF
position.

REMOTE

CONDENSER

SECURED?

PLUMBING?

15. Switch on the electrical power.

16. Refer to Pre-Start instructions, the next page.

NME650R

ROOF

HOLES

SEALED?

POWER

SUPPLY?

LEVELED?

August 1993

Page 11

NME650R

START UP

Pre-Start Inspection

1. Remove the front, left , an d righ t side service
panels.

2. Check that an y sty rofo am sh ipping block s hav e
been removed.

3. Inspect the interio r of the mach ine for loos e
screws or wires. Check that no refrige rant lines
are rubbing ea ch oth er. Che ck th at the fan blad e
turns freely (remot e conden ser).

Start Up

1. Go through the pre-start inspection.

2. Open the ha nd v alve , ob serve that water enter s
the water reservoir, fills the tube from the reservoir
to the evaporator, and then shuts off. Check for
leaks.

4. Check that the refrige ran t line s are properly
installed .

5. Check that the electrica l powe r has been on for
at least 4 hours.

6. Check that the unit is insta lled correctly
according to the fin al check list on page 11.

6. The unit should so on be making ice , if de sired
the low side pressure can be checked, it should be
30 psig + or - 4 psig. The discharge pressure will
depend upon air and water temp eratures, but
should be between 180 psig and 300 psig.

3. Ope n the Kin g Valve.

4. Turn the master swit ch on.
The electrical start up sequence is now on

automatic.
A. There should be a short (15 second) delay

before the gearmotor sta rts.
B. After the gearmotor sta rts, the liquid line va lve

will open, the low pressure cont rol will close and
the compressor will start.

5. The remote condenser fan turns, and the
condenser begin s to discha rge warm air.

7. THERE ARE NO ADJUSTMENTS TO MAKE,
so replace the panels.

8. Clean and/or sanitize the storage bin interior,
wipe off the exterior with a clean, damp cloth.

9 Give the owner/use r the serv ice man ua l, ins truc t
him/her in the operatio n of the unit , and mak e sure
they know who to call for service.

10. Fill out the manufacturers registration card,
and mail it to the Scotsman Factory.

11. Fill out the field quality audit form, and mail it to
the Scotsman fac to ry .

April 1995

Page 12

COMPONENT DESCRIPTION

CLEANING

DRAIN TUBE

EVAPORATOR

GEAR MOTOR

ICE CHUTE

NME650R

Control Box: Contains the electrical controls that

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

sensing the high side refrigeration pressure. It is
set to shut the machine off at 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.

CONTROL BOX

Ice Discharge Chute: Directs the ice produced

by the evaporator into the storage bin.
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.

Gear Motor: An oil filled, speed reduction
gearbox, driving the auger.

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

Compressor: The refrigerant vapor pump.
Expansion valve: The refrigerant metering

device.

HIGH PRESSURE

CUT OUT

COMPRESSOR

EXPANSION VALVE

WATER LEVEL

SENSOR

RESERVOIR

ICE LEVEL

SENSOR

August 1993

Page 13

NME650R

COMPONENT DESCRIPTION: Control Box

Contactor: A definite purpose contactor
connecting the compressor and the remote
condenser fan motor to the power supply.

Circuit Board: The circuit board receives input
signals from several sensors and tranlsates them
to control the electrical power to the various loads.

The sensors inlcude:

••ice level in the bin (with electric eyes)

••Water level in the reservoir (with a thermisitor)

••Amp draw of the auger drive motor

ON/OFF SWITCH

PUMP DOWN CONTROL

The loads include:

••Liquid line coil

••Auger drive motor

Pump Down Control: An automatic reset
pressure switch connected to the low side of the
refrigeration system. Controls the compressor.

Potential Relay: The compressor start relay.
On/Off Switch: Manual control for the machine.

POTENTIAL RELAY

TRANSFORMER

CIRCUIT

BOARD

CONTACTOR

June 1994

Page 14

ELECTRICAL SEQUENCE

NME650R

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 liquid line relay and auger motor relay

become energized, connecting power to the
liquid line solenoid coil and to the windings of
the auger motor.

••The liquid line solenoid opens, raising the low

side pressure.

••The pump down control closes.

••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 liquid line solenoid closes, lowering the

suction pressure.

••The pump down control 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
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"

••When the water refills the reservoir, the

machine will start up again.
Separate from the circuit board:

••The high pressure control will stop the machine

immediately if it opens. It is manually reset at

the control and at the reset switch on the circuit

board.

••The master switch is the manual control for the

complete machine, but it is not a service

disconnect.

August 1993

Page 15

NME650R

OPERATION: Water

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

Water Level: The correct water level should be

checked when the machine is making ice. Locate the

water level in the reservoir and compare it to the

horizontal line molded into the side of the reservoir.

The correct level should be between

1

⁄4" below the line. If needed, bend the float arm up or

down to adjust the water level.

RESERVOIR

1

⁄8" above and

DRAIN TUBE

Reservoir overflow or evaporator condensation is
routed to the drain.

WATER

INLET

WATER LEVEL

DRAIN

June 1994

Page 16

OPERATION: Refrigeration

THERMOSTATIC

EXPANSION

VALVE

NME650R

Beginning at the compressor, the refrigerant is
compressed into a high temperature gas. The
discharge line directs this gas to the condenser.
At the remote condenser the gas is cooled by air
and condenses into a liquid. This high pressure
liquid then goes through the liquid line to the head
pressure control valve, into the receiver, through
the liquid line valve and then through the
expansion valve.

Refrigeration Schematic

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
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.

REMOTE CONDENSER

DISCHARGE

LINE

HEAD

PRESSURE

CONTROL

VALVE

LIQUID LINE

DETAIL OF HEAD

PRESSURE CONTROL

VALVE

LIQUID LINE

VALVE

EVAPORATOR

KING

VALVE

SUCTION

LINE

RECEIVER

COMPRESSOR

August 1993

Page 17

THERMOSTATIC

EXPANSION

VALVE

REMOTE CONDENSER

EVAPORATOR

NME650R

OPERATION: Refrigeration

Low Condensing Temperature

The refrigeration system under low condenser air
temperatures is much the same as it is under
higher temperatures, with the exception that the
resulting low head pressures cause the head
pressure control to close off the liquid line between
the condenser and the receiver.

DISCHARGE

LINE

LIQUID LINE

This forces more refrigerant into the condenser
(with a small amount of discharge gas going into
the receiver to maintain pressure until the head
pressure is built back up to the rated gauge
pressure of 180 psig). At that pressure the valve
opens up the liquid line from the condenser to the
receiver.

Refrigeration Schematic

DETAIL OF HEAD

PRESSURE CONTROL

VALVE

HEAD

PRESSURE

CONTROL

VALVE

LIQUID LINE

VALVE

KING

VALVE

SUCTION

LINE

RECEIVER

COMPRESSOR

June 1994

Page 18

OPERATION: Refrigeration

REMOTE CONDENSER

THERMOSTATIC

EXPANSION

VALVE

EVAPORATOR

NME650R

PUMP DOWN

During the pump down cycle (usually initiated by
the circuit board de-energizing the liquid line valve)
the discharge gases flow through their normal path
to the remote condenser, through the head
pressure control, and into the receiver.

DISCHARGE

LINE

LIQUID LINE

At this point the refrigerant flow is stopped by the
closed liquid line valve. This action forces the
refrigerant into the receiver and keeps it out of the
compressor. The pump down continues until the
low pressure control turns the compressor off.

Refrigeration Schematic

HEAD

PRESSURE

CONTROL

VALVE

LIQUID LINE

VALVE

KING

VALVE

SUCTION

LINE

RECEIVER

COMPRESSOR

August 1993

Page 19

NME650R

CLEANING & 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 RESPONSIBILITY to see that the
unit is properly maintained. It is always preferable,
and less costly in the long run, to avoid possible

Note: Electrical power will be ON when doing in place cleaning.
ICE MAKING SYSTEM: In place cleaning

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

2. Remove screws and the front and top panels.

3. Move the ON-OFF switch to OFF.

4. Remove all the ice from the storage bin.

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

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

7. Prepare the cleaning solution: Mix eight
ounces of Scotsman Ice Machine Cleaner with
three quarts of hot water. The solution should be

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

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

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.

11. Repeat step 6 to drain the reservoir. Wash and
rinse the water reservoir.

Sanitizing:
To sanitize, use an approved sanitizing solution or

mix one ounce of household bleach with 2 gallons
of warm (95
8-11 using the sanitizer solution in place of the
cleaning solution.

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.

///////////////////////////////CAUTION///////////////////////////////
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 panels.

o

F. to 115oF.) water. Repeat steps

between 90 and 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.

June 1994

Page 20

MAINTENANCE AND CLEANING

SLIDE UP

TO REMOVE

NME650R

ICE CHUTE

Electrical Shock
Hazard.

Electrical shock can
cause personal injury.
Disconnect electrical
power before beginning.

1. 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 base of the ice chute,
and wipe the inside clean, as illustrated.

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

RESERVOIR

ICE LEVEL

SENSORS

SLIDE LEFT TO

REMOVE

Inspect the assembly, looking for wear

4. Clean the remote condenser. Use a vacuum
cleaner or coil cleaner if needed.

Do NOT use a wire brush.

5. Check and tighten all bolts and screws.

WATER LEVEL

SENSOR

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

CAUTION: THE TIP

IS MADE OF GLASS

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

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

Check the breaker bearing by:

••removing the ice chute cover

unscrewing the ice sweep

••

••removing the water shed

••unscrewing the breaker cover (left hand thread)

••

unscrewing the auger stud

ICE

SWEEP

BREAKER

COVER

August 1993

Page 21

NME650R

MAINTENANCE AND CLEANING

In some areas the water supply to the icemaker
will have a great deal of minerals in it, 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 and
replacement of these parts, see REMOVAL
AND REPLACEMENT.

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

2. Move bail clamp holding ice chute cover to ice
chute, and remove cover.

Bail Clamp

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. Replace the water seal.

8. Reverse to reassemble.

ALLEN

SCREWS

BREAKER

& BEARING

& AUGER

ASSEMBLY

June 1994

Page 22

OPERATING CHARACTERISTICS

Typical Low Side Pressure

•• 28 - 32 PSIG

Typical Discharge Sid e Pre ss ure

•• 240 PSIG, will vary bewteen 180 and 380 depending upon air and water temperatures

Refrigerant Charge

•• 208 ounces of R-404A

Typical Compressor Amp Draw

•• 8 - 9

Typical Gearmotor Amp Draw

•• 3.5 to 3.8

High Pressure Cut Out

•• 450 PSIG

NME650R

Pump Down Pressure Switc h - af ter May 1995 production

•• Opens at 15 PSIG (was 2 PSIG)

•• Closes at 30 PSIG (was 17 PSIG)

Compressor

•• RS58CiE-PAA-213

Bin Control

••Electric Eye at base of ice chute.

Water Safety

••Thermistor in reservoir

June 1995

Page 23

NME650R

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

STATUS:

NOTHING OPERATES

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 reset switch (high pressure): depress and release the switch. If the unit still does

not start, check the high side pressure.

D. Check the high pressure cut out switch.

1. This pressure switch opens at 450 psig. Check the high side pressure, reset the switch and observe that
the fan is forcing air through the condenser. If the switch opens at pressures below 450 psig, replace the
switch. If the pressures rise above the trip out point, and the unit shuts down:

a. Check for adequate air flow. Clean the condenser. 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.
b. Check the head pressure control valve, it should be maintaining a head pressure
above 180 psig. If the unit has the correct charge, and the condenser is clean, and the
refrigerant lines are not kinked or twisted, and the condenser is not overheated by
external heat loads, the head pressure should be under the trip out point of the head
pressure control switch. If all of the above are found to be good, and the machine
trips out on high head pressure, replace the head pressure control valve.

E. Check the water level. If there is not enough water in the reservoir, the water level sensor will
keep the machine from starting.

a. Check the water level, restore/adjust if low.
b. Check the water level sensor, clean if dirty, (see maintenance).
c. Check the circuit board, see next page.

If the machine does not start, see the next page.

June 1994

Page 24

NME650R

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

STATUS:

NOTHING OPERATES

F. 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.
a. Transformer "load" side should have 12 to 15 volts. If not, check the "line" side.
The line side should be line voltage. If the line side has the correct

voltage and the load side does not, replace the transformer.

2. If the transformer is good, and the bin empty light is OFF, check the ice level sensors.
a. Remove sensors by sliding them sideways out of the ice chute. 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

Tester Model NM1 into the circuit board (see page 36).

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.

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

MORE INFORMATION ON THE TESTER MAY BE FOUND ON THE LAST PAGE OF THE MANUAL.

August 1993

Page 25

NME650R

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

STATUS:

GEARMOTOR OPERATES, COMPRESSOR DOES NOT

A. Check the pump down control switch.

1. This pressure switch opens at 15 psig, and closes at 30 psig. If open check the low side pressure, if after

running the machine the switch opens at a pressure higher than 18 psig, replace the switch.

The pump down control could remain open for any of the f ol lo win g rea so ns : Low refrigerant charge, au ge r

not turning, restricted system, TXV not opening, liquid line valve not opening.

2. Check the low side pre ss u re , the pump down control shou ld remain closed at any pres s ur e hig her than

15 psig. If less than that:

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 begins to 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 charg e.

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

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

c. Check the liq ui d line solenoid valv e, it should hav e p ower to it, if not:

Check the connections on the circuit board. The liquid line (or compressor) relay

on the circuit board may have failed. If so, replace the circuit board.

If there is power to the valve, the coil may be open, or the valve jammed, replace

the valve.

Note: The pump down control setting changed beginning with May 1995 production. CI was 17, CO was 2.

June 1995

Page 26

SERVICE DIAGNOSIS: Condition - Low Ice Production

NME650R

STATUS:

EVERYTHING IS OPERATING

A. Check the condenser for dirt. Clean as required. Check the head pressure. If the head
pressure is very high:

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

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

3. Check the interconnecting refrigerant tubing for kinks or twists.
Check that the discharge and liquid lines are insulated, and do not touch each other
where not insulated.

B. Check the evaporator

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 30 psig. If low, assume a refrigerant leak, 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 of foam tape
to the evaporator.

C. Check the compressor

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.

D. Refrigerant charge

On this model the refrigerant charge is adequate whenever the receiver has enough liquid refrigerant to
maintain liquid refrigerant at the TXV. HOWEVER, the condensing temperature will have a definite bearing
on this. A unit with a marginal charge in summer, will be undercharged when the outside air temperature
drops. The only correct way to charge this unit is to weigh in the nameplate charge.

August 1993

Page 27

NME650R

REMOVAL AND REPLACEMENT: Water Reservoir & Bin Controls

WATER RESERVOIR

1. Shut off the water supply to the icemaker.

2. Remove front panel and reservoir cover.

3. To remove float only, disconnect water inlet

compression fitting at reservoir inlet, push in on
locking tab, pull float up and out of the reservoir.

Note: there is a separate plunger/seat inside the
valve assembly that may be replaced.

4. To remove reservoir, disconnect water outlet at

reservoir base.

5. Remove drain hose from reservoir.

6. Remove water level sensor 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 ice chute, at the base of the chute, in
front of and behind it are two plastic bin control
mounts.

5. Slide each bin control to the left, 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.

FLOAT

ASSEMBLY

Valve

Seat/Plunger

LOCKING TAB

ICE

CHUTE

SLIDE BIN

CONTROLS IN

AND OUT

June 1994

Page 28

REMOVAL AND REPLACEMENT: Bearing And Breaker

Step 5-c and Step 6

NME650R

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

To Remove the Breaker Bearing Assembly:

Electrical Shock
Hazard.

Electrical shock can
cause personal injury.
Disconnect electrical
power before beginning.

1. Remove panels and disconnect electrical power.

2. Push bail clamp back and remove ice chute

cover.

3. Unscrew and remove ice sweep.

4. Remove insulation halves from outside of ice

chute, lift up and remove ice chute.

5. The breaker may be removed from the auger

and evaporator without disturbing the auger.
a. Unscrew breaker cover from breaker (left hand

threads)
b. Unscrew auger stud from top of auger.

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

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. A29123-001 bearing grease.
Replace top seal, and check the o-rings, replace if
cut or torn.

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

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

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

Step 5-a Step 5-b

ICE

SWEEP

BREAKER

AUGER

STUD

ALLEN

SCREWS

August 1993

Page 29

DRIVE SLIDE UP AGAINST
STOP TO LOOSEN AUGER

NME650R

REMOVAL AND REPLACEMENT: Auger

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, or, if that is not

possible, the gearmotor and freezer assembly
must be pulled part of the way out from the
cabinet. To do that:

a. Unclip the electrical wires from the hanger near
the drive motor.

b. Remove the bolt holding the gearmotor plate.
c. Pull the assembly out.

2. The auger and breaker/bearing may now be

removed as an assembly.
a. Unscrew 4 allen head cap screws holding

breaker to evaporator.
b. Lift up on

breaker and
remove auger from
evaporator.

BREAKER - BEARING

ASSEMBLY

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

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

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

b. Unscrew auger
stud from top of auger.

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

d. Lift up on breaker to remove from auger.
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:

a. 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.

//////////////////////////////WARNING////////////////////////////////
Ice machine cleaner is an acid. Handle it with

extreme care, keep out of the reach of children.
///////////////////////////////////////////////////////////////////////////////
b. The water seal area. Because the auger has

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

STOP

SLIDE HAMMER

PULLER REMOVING

AUGER

THREAD

INTO

AUGER

June 1994

Page 30

REMOVAL AND REPLACEMENT: Water Seal

WATER SEAL

RETAINING

RING

To Remove the Water Seal:

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

1. The gearmotor/evaporator assembly will have to

be pulled away from the machine (if not yet done).

2. Remove the 4 hex head cap screws holding the

evaporator to the gearmotor assembly. Lift the
evaporator up and off of the gearmotor.

3. Remove the snap ring or wire retainer from the

grove under the water seal.

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

To Replace the Water Seal:

1. Lubricate the water seal with water, and push

the water seal into the bottom of the evaporator
slightly past the grove for the snap ring.

2. Replace the snap ring and pull the water seal

down against it.

3. The part of the water seal that rotates with the

auger must also be replaced. Remove the old part
from the auger and clean the mounting area.

4. Place a small bead of food grade silastic sealant

(such as 732 RTV or Scotsman part number
19-0529-01) on the area of the auger where the
water seal is to be mounted.

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 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.

REMOVAL OF THE WATER SEAL

NME650R

August 1993

Page 31

NME650R

REMOVAL AND REPLACEMENT: Evaporator

To Replace the Evaporator:

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

1. Discharge and recover the refrigerant from the

ice maker.

2. Unsweat the refrigerant connections:

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”)
resweat the tubing connections.

6. Install an new drier in the liquid line.

7. Evacuate the system until dehydrated, then

weigh in the nameplate charge. Check for leaks.

8. Install auger, breaker, breaker bearing

assembly, and ice discharge chute in reverse
order of disassembly. See “To Reassemble
Evaporator and Auger”

To Reassemble the Evaporator and Auger

1. After the gearmotor has been inspected, fasten

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

2. Lower the auger into the evaporator barrel,

slightly turning it to match up with the drive end.
Do Not Drop Into the Evaporator.

3. Complete the reassembly by reversing the

disassembly for the breaker & thrust bearing
assembly.

Head Pressure Control Valve

1. Recover system of refrigerant

2. Break off process tube on the top of the OLD
head pressure control valve.

3. Unsweat old valve from tubing.

4. Unsweat old dryer from tubing.

5. Install new valve in place, check for correct
connections and be sure the number on the side of
the valve is “180"

6. Wrap the new valve body in wet cloths to heat
sink the valve body.

7. Sweat in the new valve and the new dryer.

8. Evacuate the system, and weigh the nameplate
charge into the receiver.

PLACE A BEAD OF
FOOD GRADE
SEALANT HERE

June 1994

Page 32

REMOVAL AND REPLACEMENT: Gearmotor Assembly

WATER SHED

DRIVE MOTOR

OUTPUT GEAR,

OUTPUT SHAFT,

AND BEARINGS

BEARING

SEAL

GASKET

NME650R

To Remove and Repair the Gearmotor
Assembly:

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

1. Remove the electrical wires from the gear drive

motor.

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.

August 1993

GEARCASE

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 the cover is lowered
onto the lower case, the 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.

Page 33

CHARGING

CYLINDER

Access Valves

Note: There are no valve

cores in this valve.

NME650R

REFRIGERATION SERVICE

General Information:

Work on the refrigeration system should only 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 draw, voltage, and other
techniques will lead to proper diagnosis.
Scotsman also recommends that, at the time of
initial start up, gauges not be used.

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

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

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

to minimize refrigerant discharged into the air.

••Refrigerant should not be added except as a

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

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

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

••Anytime the refrigeration system has been

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

••When brazing the tubing connections to

components such as the TXV, the component

must be protected by heat sink material.
Recover, reclaim or recycle refrigerant. The
method chosen is up to the service company. Any
refrigerant placed into a Scotsman ice machine
must meet ARI spec 700-88. 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 the valve and replace the caps when the
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.

Charging Procedures

Extra care must be taken when recharging this
remote system. No liquid refrigerant may be
placed in the system at the compressor.

RECEIVER

DO NOT use the valves at the front of the unit for
weighing in the charge. All liquid HP62 must be
weighed into the receiver through the “front
seated” king valve".

FRONT SEATED

KING VALVE

SERVICE PORT

June 1994

Page 34

REFRIGERATION SERVICE: R-404A

THIS ICE MACHINE USES R-404A (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 preferred.

••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
detector capable of detecting a Halogenated
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.

August 1993

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Page 35

NME650R

Pressure-Temperature Chart for HP62

NME650R

CIRCUIT BOARD TESTING:

Electrical Shock Hazard.

Electrical shock can cause
personal injury.
Disconnect electrical
power before connecting
tester.

INSTRUCTIONS FOR USING TESTER (Optional,
order part no. A33942-001)

(These instructions assume that the unit will not

PHOTO TRANS

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.

3. Unplug “water sen” connector from control
board.

4. Plug “water sen” connector from Scotsman
tester into circuit board.

Bin Control
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.
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.

Water Level

a. Move “water” switch on tester to No Water
position. The No Water light on the circuit board

LIGHT ON

LED

LIGHT

GOES ON

SWITCH TO

“FULL”

run, and prior investigation of electric power,
controls, and mechanical parts indicates that the
electronic circuit may be at fault.)

Note: Testing is done with the electrical power
on, the master switch on, and all the reset
switches “reset”.

WATER SENS

SWITCH TO

“NO WATER”

should go ON. If not, replace the circuit board.
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.

If the Bin Empty light is ON, wait 10-20 seconds for
the machine to start.

June 1994

Page 36