Scotsman NM1852R Installation Manual

INTRODUCTION

NM1852R

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 NM1852R is a remote condenser modular ice
system. 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
R-22 as the refrigerant.

TABLE OF CONTENTS

For the Installer

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

Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Remote Condenser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

For the Plumber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

For the Electrician . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Final Check List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Component Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

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

Maintenance & Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Service Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Removal and Replacement

Water Reservoir & Bin Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Thrust Bearing & Breaker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Auger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Water Seal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Evaporator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Gearmotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Refrigeration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Circuit Board Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

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

December 1992

Page 1

Drain 3/4" FPT

18.28"

NM1852R

FOR THE INSTALLER

The NM1852R is designed to fit the
following Scotsman storage bins:

••B90 and extentions, with bin top

KBT18.

••BH800 no bin top needed.

••BH900 using bin top KBT14.

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.

There are two separate ice making

and refrigeration systems in this
model. The liquid and discharge

lines from each system must go to

separate circuits in one remote

condenser (RC1222).

TOP VIEW

Ice Chute

6.7" x 6.2"

BACK VIEW

Allow 6" of space behind the machine

for utility connections.

34.84"

Liquid Line
Connection

(right system)

15.53"

3.1"

21"

3.1"

13.84"

Discharge Line

Connection

(left system)

Allow 6"

above

machine for

service.

20.84"

5.25"

3"

Remote Condenser

17.8"

18.8"

21.66"

Electrical Inlet

Water Inlet 3/8" Flare

SPECIFICATIONS: ICEMAKER

Model

Number

NM1852RE-32A

NM1852RE-3A

Dimensions

(w/o bin)

H X W X D

27" x 42" x 24"

same

Basic

Electrical

208-230/60/1
208-230/60/3

Ice

Type

NUGGET

same

Cond.

Type

R/Air
R/Air

The Standard Finish is Enamel - Sandalwood. There is an optional stainless steel panel kit, SPKFM42
available to convert the unit to Stainless Steel. It is field installed.

December 1992

Page 2

4.5"

9.43"

Junction Box

FOR THE INSTALLER

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.

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 is not intended as a complete
resource for water related questions, but it does
offer these general recommendations:

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

2. In most cases, the water used to make ice
should be filtered or treated, depending upon the
water.

There is no one type of water filter that

will be effective in all situations.

water test is important.

F 1000F

0

F 1000F

That is why a

NM1852R

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.

1.25"

December 1992

Page 3

Typical Storage Bin - B90

21.12"

Drain

3/4"
FPT

19.86"

NM1852R

REMOTE CONDENSER SPECIFICATIONS

1/2" MALE QUICK CONNECT

COUPLING FOR USE WITH

RT2225 OR RT2240

PRECHARGED LINE SET

22"

5.75"

5.38"

32.56"

27.81"

5.0"

MODEL USE WITH MINIMUM CIRC.

RC1222 27.8" X 22 X 37.94" 1 NM1852R 2 208-230/60/1

+Included with the ice maker’s minimum circuit ampacity. Use this

value to determine wire size between icemaker and fan motor.

DIMENSIONS
H" X W" X D"

6.5"

3.5"

1.9"
LIQUID LINE 3/8" MALE

QUICK CONNECT

COUPLING FOR USE WITH

RT2225 OR RT2240

PRECHARGED LINE SET

RT-2225 Precharged line set, 25’, R-22 - 2 required.
Or: RT-2240. Precharged line set, 40’, R-22 - 2 required.

7.5"

AMPACITY+

BASIC

ELECTRICAL

ICEMAKER NAMEPLATE

LOCATED ON BACK PANEL

SERIAL PLATE LOCATED

BEHIND FRONT PANEL

December 1992

Page 4

FOR THE INSTALLER

Typical Storage Bin with Extension and Bin Top

NM1852R

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 on page

3.

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.

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.

December 1992

Page 5

REMOTE CONDENSER

SPIRAL

EXCESS

TUBING

INSIDE

BUILDING

NM1852R

FOR THE INSTALLER: Remote Condenser

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, next page for connecting
instructions.

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

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 (as
illustrated) to avoid any traps in the lines.

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

Note: Tight spiral shown not required. Bend tubing

as tight as is practical.

Refrigerant charge is in the ice machine receiver.

Only a holding charge is in the "pre-charged" lines.

LOCATE REMOTE

CONDENSER

ABOVE ICEMAKER

December 1992

Page 6

FOR THE INSTALLER: Precharged Lines

COUPLING INSTRUCTIONS

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

self sealing when installed properly. Carefully
follow the instructions:

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

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.

3. Begin tightening the couplings together by
hand,

••Connect the 3/8 inch liquid line (schrader valve

end) to the remote condenser fitting marked
"liquid line".

••Connect the other end of the liquid line to the

icemaker fitting marked "liquid line."

••Connect the 1/2 inch discharge line (schrader

valve end) to the remote condenser fitting
marked "discharge line".

••Connect the other end of the liquid line to the

icemaker fitting marked "discharge line".

4. 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.

5. 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.

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

NM1852R

SERVICE PORTS

REMOTE CONDENSER

3/8" LIQUID LINE

1/2" DISCHARGE

LINE

3/8" LIQUID LINE

SCHRADER

VALVE

CONDENSER

TO REMOTE

1/2" DISCHARGE

LINE

NO SCHRADER

VALVE

TO ICEMAKER

December 1992

Page 7

ICEMAKER

NM1852R

FOR THE INSTALLER: Location

CONTACT ROOFING

CONTRACTOR

EXCESS

PRECHARGED

TUBING INSIDE

BUILDING

REMOTE

CONDENSER

ROOF

CUTAWAY

SERVICE

ACCESS

SERVICE ACCESS

SIDE AND BACK

WALL

CUTAWAY

December 1992

Page 8

FOR THE PLUMBER

CONFORM TO ALL APPLICABLE CODES

NM1852R

Water Inlet

CONNECT TO

COLD WATER

FIELD

SUPPLIED

WATER FILTER

HAND SHUT

OFF VALVE

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

December 1992

Page 9

NM1852R

FOR THE ELECTRICIAN

CONFORM TO ALL APPLICABLE CODES

The electrical power to the unit is supplied through
the junction box at the rear of the machine.

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

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

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

TERMINAL STRIP

FOR REMOTE

CONDENSER

ICEMAKER

JUNCTION BOX

POWER

SUPPLY

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 rain proof 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

RAIN PROOF

CONDUIT

December 1992

Page 10

FOR THE INSTALLER: Completed Installation

INSULATED

PRECHARGED

REFRIGERANT

TUBING

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.

NM1852R

December 1992

Page 11

NM1852R

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, right
and above the machine for
proper service access?

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

7. Has the machine been
secured to the bin?

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

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

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

11 Have the remote condenser
and precharged lines been
properly installed?

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

13. Verify that the master
switches are in the OFF position.

14. Switch on the electrical
power.

REMOTE

CONDENSER

SECURED?

LEVELED?

PLUMBING?

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

ROOF

HOLES

SEALED?

POWER

SUPPLY?

December 1992

Page 12

START UP

NM1852R

Pre-Start Inspection

1. Remove the front, left, and right side service
panels.

2. Check that any styrofoam shipping blocks have
been removed.

3. Inspect the interior of the machine for loose
screws or wires. Check that no refrigerant lines
are rubbing each other. Check that the fan blade
turns freely (remote condenser).

Start Up

1. Go through the pre-start inspection.

2. Open the hand valve, observe that water enters
the water reservoirs, fills the tubes from the
reservoirs to the evaporators, and then shuts off.
Check for leaks.

4. Check that the refrigerant lines are properly
installed.

5. Check that the electrical power has been on for
at least 12 hours and that the compressor domes
are warm.

6. Check that the unit is installed correctly
according to the final check list on page 12.

6. The unit should soon be making ice, if desired
the low side pressure of each system can be
checked, it should be 25 psig + or - 2 psig. The
discharge pressure will depend upon air and water
temperatures, but should be between 200 psig and
280 psig.

3. Open each King (receiver service) valve.

4. Switch each master switch on.
The electrical start up sequence is now on

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

before the gearmotor starts.
B. After the gearmotor starts, the liquid line valve

will open, the low pressure control will close and
the compressor will start.

5. The remote condenser fan turns, and the
condenser begins to discharge 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/user the service manual, instruct
him/her in the operation of the unit, and make 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 factory.

December 1992

Page 13

NM1852R

COMPONENT DESCRIPTION

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 400 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.

NOTE: THERE ARE TWO OF

EACH OF THE LISTED

COMPONENTS IN A NM1852R

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.

EXPANSION VALVE

WATER LEVEL

SENSOR

ICE CHUTE

RESERVOIR

HEAD PRESSURE
CONTROL VALVE

COMPRESSOR

CLEANING

DRAIN TUBE

EVAPORATOR

GEAR MOTOR

ICE LEVEL

SENSOR

CONTROL BOX

HIGH PRESSURE

CUT OUT

December 1992

Page 14

COMPONENT DESCRIPTION: Control Box

There are two control boxes in the machine.

NM1852R

Contactor: A definite purpose contactor

connecting the compressor and the remote
condenser fan motor to the power supply.

Circuit Board: Controlling the ice machine

through sensors and relays. The sensors are: ice
level, and water level. The relays are for the gear
motor (with a built in time delay to clear the
evaporator of ice when the unit turns off) and for
the liquid line valve.

ON/OFF SWITCH

PUMP DOWN CONTROL

Transformer: Supplies low voltage to the circuit

board.

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

December 1992

Page 15

NM1852R

ELECTRICAL SEQUENCE

Refer the wiring diagram as needed.
The two ice making systems operate

independently except for the fan motor of the
remote condenser. If either one of the systems is
operating, the fan will be ON.

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 fan motor relay.

••The fan motor and the compressor start.

••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 and fan motor stop (unless the

other ice making system is on, then the fan
motor stays ON).

••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 .

••The spout switch will stop the machine

immediately if it opens. It is a manual reset

reset switch.

••A master switch is the manual control for each

system, but it is not a service disconnect.

December 1992

Page 16

OPERATION: Water

NM1852R

Water enters the machine through the 3/8" male
flare at the rear of the cabinet, divides into two inlet
lines to each water reservoir which it enters
through the float valve. The water them goes out
the bottom of the reservoir tanks to the bottom of
the evaporators.

Reservoir overflow or evaporator condensation is
combined into a common drain line and routed to
the drain.

ADJUSTMENT OF WATER LEVEL

DRAIN

CHUTE

WATER INLET

ICE

RESERVOIR

EVAPORATOR

WATER

LEVEL

STRAINER

EVAPORATOR

DRAIN

WATER SCHEMATIC

December 1992

Page 17

THERMOSTATIC

EXPANSION

VALVE

NM1852R

OPERATION: Refrigeration

There are two separate refrigeration systems in this machine.

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 it then 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.

The thermostatic expansion valve meters liquid
refrigerant into the evaporator, the volume of liquid

Refrigeration Schematic

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

December 1992

Page 18

OPERATION: Refrigeration

THERMOSTATIC

EXPANSION

VALVE

EVAPORATOR

REMOTE CONDENSER

There are two separate refrigeration systems in this machine.

Low Condensing Temperature

NM1852R

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 220 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

KING

VALVE

RECEIVER

LIQUID LINE

VALVE

December 1992

Page 19

SUCTION

LINE

COMPRESSOR

REMOTE CONDENSER

EVAPORATOR

THERMOSTATIC

EXPANSION

VALVE

NM1852R

OPERATION: Refrigeration

PUMP DOWN

There are two separate refrigeration systems in this machine.

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.

Refrigeration Schematic

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.

DISCHARGE

LINE

HEAD

PRESSURE

CONTROL

VALVE

LIQUID LINE

LIQUID LINE

VALVE

KING

VALVE

SUCTION

LINE

RECEIVER

COMPRESSOR

December 1992

Page 20

NM1852R

MAINTENANCE AND CLEANING

The NM1852R is made up of two separate ice makers; to properly clean and maintain the NM1852R,
these steps must be followed for both systems.

A Scotsman Ice System represents a sizable investment of time and money in any company’s
business. In order to receive the best return for that investment, it MUST receive periodic
maintenance.
It is the USER’S RESPONSIBILITY to see that the unit is properly maintained. It is always
preferable, and less costly in the long run, to avoid possible down time by keeping it clean;
adjusting it as needed; and by replacing worn parts before they can cause failure. The following
is a list of recommended maintenance that will help keep the machine running with a minimum of
problems.
Maintenance and Cleaning should be scheduled at a minimum of twice per year.

WARNING
Electrical power will be ON when doing in

place cleaning. Switch it OFF before
completing the cleaning process.

ICE MAKING SYSTEM: In place cleaning

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

2. Remove screws and the front panel.

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.

WARNING
Scotsman Ice Machine Cleaner contains

acids. These compounds are corrosive and
may cause burns. If swallowed, DO NOT
induce vomiting. Give large amounts of
water or milk. Call Physician immediately.
In case of external contact, flush with water.
KEEP OUT OF THE REACH OF CHILDREN.

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

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

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

13. Switch the master switch to ON

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

WARNING
DO NOT USE any ice produced from the

cleaning solution. Be sure no ice remains in
the bin.

15. Remove all ice from the storage bin.

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

17. Sanitize the bin interior with an approved
sanitizer using the directions for that sanitizer.

18. Replace the front panel.

December 1992

Page 21

NM1852R

MAINTENANCE AND CLEANING

The NM1852R is made up of two separate ice makers; to properly clean and maintain the NM1852R,
these steps must be followed for both systems.

WARNING
Disconnect electrical power before beginning.

ICE CHUTE

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.

SLIDE UP

TO REMOVE

RESERVOIR

WATER LEVEL

SENSOR

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.

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

CAUTION: THE TIP

IS MADE OF GLASS

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

3. The top bearing in the breaker should also be
checked at least

Check the breaker bearing by:

two times per year.

••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

December 1992

Page 22

MAINTENANCE AND CLEANING

NM1852R

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.

ALLEN

SCREWS

BREAKER

& BEARING

& AUGER

ASSEMBLY

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.

Shut off water and electrical supply.

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

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

3. Unscrew and remove ice sweep.

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

5. Remove 4 allen screws holding breaker to
evaporator.

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

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

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

7. Replace the water seal.

8. Reverse to reassemble.

December 1992

Page 23

NM1852R

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 2 reset switches (spout switch, or on prior models, the circuit board; and high

pressure): depress and release each switch. If the unit still does not start, check the spout switch,
or high side pressure.

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

1. This pressure switch opens at 400 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 400 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 220 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 spout switch.

1. This switch will open if the bin control (ice level sensor) does not shut the machine off when the ice
storage bin is full of ice: ice backs up in the ice chute, and internal pressure opens the switch, stopping the
machine. If the machine does start, check:

a. The ice level sensors, they may need cleaning (see maintenance).
b. The circuit board, see next page.

F. 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.

December 1992

Page 24

NM1852R

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

STATUS:

NOTHING OPERATES

G. 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.

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

a
The line side should have between 208-230 volts. 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

. Remove sensors by sliding them sideways out of the ice chute. Visually inspect

a

them, clean if needed.

. Look through the ice chute "eye" hole for something blocking the ice chute.

b
c. If the unit still does not run, replace the ice level sensors.

. If the bin empty light is still OFF, check the circuit board.

d

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

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.

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

3

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

. Replace the water level sensor. If the no water light is still on, check that the

c
"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

bin empty light is OFF, check the ice level sensors.

.

MORE INFORMATION ON THE TESTER MAY BE FOUND ON PAGE 35.

December 1992

Page 25

NM1852R

SERVICE DIAGNOSIS: Condition - No Ice Being Produced

(Work on each system separately)

STATUS:

GEARMOTOR OPERATES, COMPRESSOR DOES NOT

A. Check the pump down control switch.

1. This pressure switch opens at 0-4 psig, and closes at 14-20 psig. If open check the low side pressure, if
after running the machine the switch opens at a pressure higher than 5 psig, replace the switch. If the liquid
line solenoid valve is open, the low side pressure should be above 20 psig, and the pump down (low
pressure) control should be closed. If the low side pressure is below 20 psig:

a. Check if the

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 25 psig) stop and look for a leak, recover, repair, replace the drier,
evacuate, and weigh in the nameplate charge. If, with added charge,
the unit does

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

nameplate charge.

Check for a

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

c. Check the liquid line solenoid valve, it should have power 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.

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

not operate:

Thermostatic Expansion Valve that does not open, if defective,

December 1992

Page 26

SERVICE DIAGNOSIS: Condition - Low Ice Production

NM1852R

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 25 psig. If low, assume a refrigerant leak, locate, recover
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
drops. The only correct way to charge this unit is to weigh in the nameplate charge.

undercharged when the outside air temperature

December 1992

Page 27

FLOAT

ASSEMBLY

NM1852R

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, pry the mounting flanges

apart enough to lift one float pivot pin out of the
flange hole, and pull float up and out of the
reservoir.

4. To remove reservoir, disconnect water inlet

compression fitting at reservoir inlet.

5. Remove drain hose from reservoir.

6. Remove evaporator inlet hose from reservoir.

7. Remove mounting screws from reservoir

bracket, and remove reservoir from icemaker.

8. Reverse to reassemble.

SLIDE BIN

CONTROLS IN

AND OUT

ICE

CHUTE

FLOAT

MOUNTING

FLANGES

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.

December 1992

Page 28

REMOVAL AND REPLACEMENT: Bearing And Breaker

Step 5-c and Step 6

NM1852R

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

To Remove the Breaker Bearing Assembly:
//////////////////////////////WARNING////////////////////////////
Disconnect the electrical power to the

machine at the building source BEFORE
proceeding with any repair.

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

1. Remove panels and disconnect electrical power.

2. Unscrew three studs and remove ice chute

cover.

3. Unscrew and remove ice sweep.

4. Remove insulation halves from outside of ice

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

5. The breaker may be removed from the auger

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

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

breaker to evaporator.

d. Lift up, and remove breaker/bearing assembly
from auger & evaporator.

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

a. The bearing is pressed into the breaker, to
remove the bearing and replace it an arbor press
is needed.

b. Replace lower seals before installing new
bearing in breaker.

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

Replace parts as required. Re-grease bearing with
Scotsman part no. 19-0609-01 bearing grease.
Replace top seal, and check the o-rings, replace if
cut or torn.

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

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

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

Step 5-a Step 5-b

ICE

SWEEP

AUGER

STUD

ALLEN

SCREWS

December 1992

Page 29

DRIVE SLIDE UP AGAINST
STOP TO LOOSEN AUGER

SLIDE HAMMER

PULLER REMOVING

AUGER

NM1852R

REMOVAL AND REPLACEMENT: Auger

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

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.

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.

BREAKER

BEARING

ASSEMBLY

December 1992

Page 30

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 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.

Note: Repeat the above for each evaporator.

STOP

THREAD

INTO

AUGER

REMOVAL AND REPLACEMENT: Water Seal

PLACE A BEAD OF

FOOD GRADE

SEALANT HERE

NM1852R

To Remove the Water Seal:

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

1. The gearmotor/evaporator assembly will have to

be exposed (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

WATER SEAL

RETAINING

RING

December 1992

Page 31

NM1852R

REMOVAL AND REPLACEMENT: Evaporator

WARNING
Disconnect electrical power, and shut off the

water supply before beginning.

To Replace the Evaporator:

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

1. Discharge the refrigerant from the ice maker.

2. Unsweat the refrigerant connections:

a) At the thermostatic expansion valve outlet.
CAUTION

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

Head Pressure Control Valve

1. Purge 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 “220"

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.

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

3. Disconnect the water inlet tube, and 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”

Charging Procedures

Extra care must be taken when recharging this
remote system. No liquid refrigerant may be
placed in the system at the compressor. DO NOT
use the access valves at the front of the unit for
weighing in the charge. All liquid R-22 must be
weighed into the receiver through the “front
seated” king valve.

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.

Repeat the above, as required, for each system.

December 1992

Page 32

REMOVAL AND REPLACEMENT: Gearmotor Assembly

WATER SHED

SEAL

DRIVE MOTOR

OUTPUT GEAR,

OUTPUT SHAFT,

AND BEARINGS

BEARING

NM1852R

Note: There are two gearmotors in each
NM1852R.

To Remove and Repair the Gearmotor
Assembly:

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

WARNING

Disconnect Electrical Power Before
Beginning

1. Remove the electrical wires from the gear drive

motor.

2. Unscrew the 4 cap screws holding the

gearmotor to the gearmotor plate.

December 1992

SEAL

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. The oil
quantity is 14 fluid ounces, do not overfill.

Page 33

Charging Procedures

Extra care must be taken when recharging this remote system.
No liquid refrigerant may be placed in the system at the
compressor. DO NOT use the valves at the front of the unit for
weighing in the charge. All liquid R-22 must be weighed into the
receiver through the “front seated” king valve.

NM1852R

Removal and Replacement: Refrigeration System

General:

••Scotsman recommends that any work on the

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

••The access valves are at the front of the

cabinet. To use them, remove the cap from the
valve ports and the cap from the top of the
valve body. Attach gauge manifold and then
use a 3/16" allen wrench to loosen the valve.
Although pressure readings may be taken with
the valve cracked open, several turns are
required to completely open the valve.

Close
the valve and replace the caps when the
job is finished.

ALLEN

WRENCH

Torque Stem

to 6-8 ft. lb..

Torque Cap to

8-12 ft. lb..

ACCESS

VALVE

Torque Cap to

7-12 ft. lb..

••Refrigerant should not be added except as a

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

••Refrigerant must not be vented to the

atmosphere.

••This system has a critical charge, it

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

••

Anytime the refrigeration system has
been opened, the dryer should be
replaced.

RECEIVER

••When brazing the tubing connections

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

December 1992

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Specifically:
Recover, reclaim or recycle refrigerant

method chosen is up to the service company.
There are various mechanical devices that may be
used to recycle refrigerant at the field level,
however, Scotsman requires that any refrigerant
placed into a Scotsman ice machine meet ARI
spec 700-88. Reclaim programs are available
through most refrigerant wholesalers.

. The

Use conservation minded service
procedures:

••Refrain from checking refrigeration

pressures without reason.

ways to determine the proper operation of a
Scotsman ice machine without using refrigerant
gauges. Visual inspection of the water system,
observation of the ice formation, amp draw,
voltage, and other techniques will lead to proper
diagnosis. Scotsman also recommends that, at
the time of initial start up, gauges not be used.

There are many

••If gauges must be used, do not always

check the high side pressure.

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

If the

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

Minimal refrigerant discharged into the hoses
equals minimal refrigerant discharged into the
air.

••If using recycled refrigerant, it must meet ARI

spec 700-88 or have been cleaned by a
machine capable of attaining ARI spec 700-88.

FRONT SEATED KING VALVE

SERVICE PORT

CHARGING

CYLINDER

CIRCUIT BOARD TESTING

WARNING

These procedures require the machine to be
connected to the power supply. The voltages of
the electronic circuit are very low, but HIGHER
VOLTAGES ARE PRESENT IN THE UNIT. Do not
touch anything but the tester while the unit is being
checked out. Make all connections to the circuit
board with the ELECTRICAL POWER OFF.

INSTRUCTIONS FOR USING TESTER, model

FC1 (Optional, order part no. A33942-001)

(These instructions assume that the unit will not
run, and prior investigation of electric power,

controls, and mechanical parts indicates that the
electronic circuit may be at fault.)

If the "NO WATER" indicator is lit, but inspection
shows that the water level in the reservoir is above
the top of the water level sensor, OR the "BIN
EMPTY" indicator is off while inspection shows that
the ice level sensors are properly aligned, clean
and not obstructed, use the tester as follows:

Bin Control

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

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

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

Note: All testing is done with the

NM1852R

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.

SWITCH TO

“FULL”

PHOTO TRANS

LED

LIGHT

GOES ON

LIGHT GOES ON

LIGHT OFF

SWITCH TO

“BIN EMPTY”

December 1992

Page 35

NM1852R

CIRCUIT BOARD TESTING

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.

SWITCH TO

“NO WATER”

LIGHT ON

WATER SENS

LIGHT OFF

SWITCH TO

“WATER”

December 1992

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Water Level

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

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

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

NM1852R

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. The machine should start.

December 1992

Page 37