Scotsman MCM1462R Installation Manual

MCM1462R

INTRODUCTION

To the owner or user: This service manual 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.

Table of Contents

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

For the Installer

Location & Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Stacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

For the Electrician . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

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

Final Check List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Initial Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Freeze Cycle Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Harvest Cycle Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Component Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Service Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Removal and Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

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

This manual was printed on recycled paper.

April, 1993

Page 1

MCM1462R

FOR THE INSTALLER

The MCM1462R will fit Scotsman ice storage bin
MDB900 and is stackable with stacking kit
KSMCM48.
Either a Scotsman remote condenser or a Mac 6
condensing system are required to for this ice
system.

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

Scotsman assumes no liability or
responsibility of any kind for products
manufactured by Scotsman that have
been altered in any way, including the
use of any parts and/or other
components not specifically approved
by Scotsman.

Other items required:

•• Precharged tubing kit

•• Power cord and receptical

•• Condenser power cord

•• If stacking two units, a stacking kit

•• If using one unit, a caster kit for the bin.

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

Back View

Model Number Dimensions

(without bin)
W" x D" x H"

MCM1462RS-3A

48 x 24

3

⁄8 x 271⁄2

Basic
Electrical

208-230/60/3 R-22 20.5 30 256 oz. Remote Air

Refrigerant
Type

Minimum
Circuit
Ampacity*

Maximum
Fuse Size

Refrigerant
Charge**
R-22

Condenser
Type

* Minimum Circuit Ampacity is used to determine wire size and type per the National Electric Code.
** The unit is shipped with the full charge in the receiver. For re-charging purposes, if the nameplate charge

is different than this number, go by the nameplate.
Use Scotsman remote condenser RC1422, or Mac 6. Use precharged tubing kit MLS2255 (55’) or

MLS2265 (65’) or MLS2275 (75’).
Power Cord is kit number: MPC
Caster Kit is number: KBC9
This ice system (except remote condenser) is designed to be installed indoors, in a controlled environment.

MINIMUM MAXIMUM
Air Temperature 50
Water Temperature 40
Water Pressure 20 psi 80 psi
Voltage -5% +10%

0

F. 1000F.

0

F. 1000F.

April, 1993

Page 2

FOR THE INSTALLER: Location & Assembly

SHIPPING

BRACKETS

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. Try to avoid
hot, dirty and crowded locations. Be sure that the
location for the machine is within the
envrionmental limitations.

MCM1462R

Storage Bin:

Tip the storage bin on its back, using parts of the
carton to protect the exterior finish. Install the
casters, use a heavy duty leg kit if stacking two ice
machines on one bin.

1. Arrange for proper electric, water and drain.
See instructions for the plumber and for the

electrician.

2. After mounting the casters, position the ice
storage bin in the selected location:

Note: Allow enough space to the left and back to
service the machine. Do NOT push the bin into
postion, instead, lift it there. Pushing a bin may
damage the legs and leg mounts.

Level the bin in both the front to rear and side to
side directions by adjusting the leg levelers.

3. Inspect the bin top mounting gasket which
should be flat, with no wrinkles, to provide a good
water seal when the cuber is installed on top of the
bin.

ICE MACHINE AND BIN ASSEMBLY

4. Install the bin bumpers onto the top edge of the
bin, so that they hang-over the back.

Ice Maker:

Install the modular cuber on top of the bin using
care to be sure a good seal is made between the
two cabinets. Use of a mechancial lift is
recommended. Align the holes in the bottom rear
of the cabinet to mate with the two mounting holes
on the top rear of the bin.

Use bolts and straps found on the back of the ice
machine to secure the ice machine to the bin.
When alignment and leveling are completed,
tighten the bolts to secure the mounting straps.

Remove the front panel, and remove the
evaporator shipping brackets and hardware.

April, 1993

Page 3

MCM1462R

FOR THE INSTALLER: Location & Assembly

Stacking Instructions

A stacking kit, KSMCM48, is required to
interconnect the ice level controls, seal the
freezing compartments, support the bin with heavy
duty legs, and retain the front panels.

Follow the installation instructions of the stacking
kit, but in general:

The first thing to do when adding a unit is to
replace the bin casters (if the unit has been
installed with casters) wtih heavy duty legs.

Casters must not be used with two ice
machines on one bin.

When stacking two units, remove the top panel
and the evaporator cover from the lower icemaker.

STACKING

(The top removed from the lower icemaker will no
longer have any function.)

Add a strip of gasket (from the stacking kit) to the
top edge of the bottom ice machines evaporator
compartment.

Install the panel retaining bracket onto the bottom
ice machine before placing the upper unit on it.

Place additional gasket onto the top edges of the
bottom ice machine.

Carefully lift the uncrated top unit onto the bottom
one and align the two cabinets. Use of a
mechanical lift is recommended for this step.

At the back of the two icemakers, bolt the upper
icemaker cabinet to the lower icemaker cabinet
using the mounting straps and bolts from the
hardware package.

Add the relay kit to interconnect the two ice
machine’s bin control circuits.

PANEL RETAINING

BRACKET

EVAPORATOR COVER

April, 1993

Page 4

FOR THE INSTALLER: Scotsman Remote Condenser

MCM1462R

Locate the condenser as near as possible to
the interior location of the ice maker.

Location of the condenser is limited by the specific
length of precharged refrigerant tubing supplied for
the application. The pre-charged tubing connects
the icemaker to the remote condenser. The
condenser must be above the ice maker.

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

Meet all applicable building codes.
Roof Attachment:

Install and attach the remote condenser unit 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.

REFRIGERANT
CONNECTIONS

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 instructions.

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

1. Each set of precharged refrigerant lines 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, the end without
access valves goes to the icemaker.

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 1.75". 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.

TYPICAL

INSTALLATION

LOCATE CONDENSER

NO LOWER THAN ICE

MACHINE

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

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 any excess length of
pre charged tubing inside the
building. Use a horizontal spiral
to avoid any traps in the lines.

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

6. The flexible end of the tubing
must be installed behind the
icemaker; it is to be looped
down from the ice machine
connection area then back up
the wall behind the ice machine.
This allows un-stacked units to
be pulled out for service.

April, 1993

Page 5

ELECTRICAL

CONNECTION TO

ICE MACHINE

MCM1462R

FOR THE INSTALLER: Mac 6 Remote Condenser

MAC 6 INSTALLATION

DISCHARGE LINE

FROM ICE

MACHINE

LIQUID LINE

TO ICE

MACHINE

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 instructions.

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

1. Each set of precharged refrigerant lines 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, the end without
access valves goes to the icemaker.

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 1.75". 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 any 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.

6. The flexible end of the tubing must be installed
behind the icemaker; it is to be looped down from
the ice machine connection area then back up the
wall behind the ice machine. This allows
un-stacked units to be pulled out for service

Mac 6 Connections:
The condenser circuits used for the ice machine

are located in the area shown, and are labeled.
This Scotsman ice machine uses R-22, be certain

that the circuit being used also contains R-22, not
dry air or R-502.

If in doubt about the type of refrigerant, do not
complete the connections at the ice machine end
until the tubing and condenser circuit have been
connected, evacuated and a few ounces of R-22
added.

April, 1993

Page 6

FOR THE INSTALLER: Coupling Instructions

MCM1462R

////////////////////////////////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”.

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.

TIGHTENING THE QUICK CONNECTS

SCHRADER

VALVES

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

icemaker fitting marked “discharge line”.

••

The 3/8 inch liquid line goes to the icemaker
fitting marked “liquid line.”

LIQUID LINEDISCHARGE LINE

INSULATION

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.

April, 1993

Page 7

DETAIL OF JUNCTION BOX

MCM1462R

FOR THE ELECTRICIAN

SEE NAMEPLATE for current requirements to
determine wire size to be used for electrical
hookup. When the cuber and the remote
condenser are connected, each must be grounded
to the other using the ground screws provided in
the respective junction boxes. The cuber then
requires a solid chassis to chassis earth ground
wire. See Wiring Diagram.
Be certain the cuber is connected to its own
electrical circuit and individually fused. Voltage
variation should not exceed ten percent of the
nameplate rating, even under starting conditions.
Low voltages can cause erratic operation and may
be responsible for serious damage to the
icemaker.

ELECTRICAL CONNECTIONS

The Scotsman remote condenser is designed to
be powered from the ice machine. There is a
separate electrical junction box at the back of the
ice maker for the remote condenser. Wire the
remote condenser to the ice maker in accordance
with local and national electric codes. All outdoor
wiring must be in rainproof conduit.

The Mac 6 is connected to the ice machine’s
electrical circuit, but draws no power from it.

The condenser fan motor will run whenever the
compressor is running.

Electrical connections are made at the rear of
the icemaker, inside the junction box.

All external wiring should conform to the
national, state and local electrical code
requirements. Usually an electrical permit and
services of a licensed electrician will be
required.

GROUND

SCREW

HAND

DISCONNECT

SWITCH

POWER

SUPPLY

INTERCONNECTING

WIRES

REMOTE CONNECTION

April, 1993

Page 8

FOR THE PLUMBER

MCM1462R

The recommended water supply line is a 3/8-inch
O.D. copper tubing with a minimum operating
pressure of 20 PSIG and a maximum of 80 PSIG.

Connect to cold water supply line with standard
plumbing fittings, with shut off valve installed in an
accessible place between the water supply and
the cuber. ln some cases a plumber will be
required.

Water Limitations:

An ice machine is a food manufacturing plant, it
takes in a raw material, water, and turns it into a
food product, ice. The purity of the water is very
important in obtaining pure ice and in maximizing
product life. It is generally better to filter the water,
although there is no one filter that will cure all
water problems. A good filter combined with a
polyphosphate feeder gives about the best overall
performance.

DRAIN

Connections: All drains are gravity type and must
have a minimum of 1/4-inch fall per foot on
horizontal runs. The drains to be installed to
conform with the local plumbing code. Install a
vertical open vent on drain line high point to insure
good draining. The ideal drain receptacle is a
trapped and vented floor drain. Recommended bin
drain is 5/8 inch O.D. copper tubing and should be
vented and run separately. Insulation for high
humidity areas is recommended.

The ice machine sump drain is 3/4" FPT. There
must be a vent at this connection for proper sump
draining.

POTABLE

WATER

SUPPLY

HAND

SHUT OFF

VALVE

AIR GAP BETWEEN

DRAIN LINES AND

BUILDING DRAIN

SUMP DRAIN MUST

BE VENTED

3/4" FPT

OPTIONAL

FILTER

3/8" MALE FLARE

BIN

DRAIN

WATER SUPPLY AND DRAIN CONNECTION

April, 1993

Page 9

LEVEL

ASSEMBLY

SUMP DRAIN

OPTIONAL

FILTER

MCM1462R

FINAL CHECK LIST

1. Is the cabinet in a room where ambient
temperatures are within the minimum and
maximum temperatures specified?

2. Is there clearance at the left and back sides of
the cabinet for service access?

3. Has water supply pressure been checked to
insure a minimum of 20 PSIG and a maximum of
80 PSIG operating pressure?

4. Is the cabinet level?

5. Check that any shipping material has been
removed from inside the
cabinet.

6. Check that the reservoir is
properly secured to the bottom
of the evaporator plates.

7. Have all electrical, water and
drain connections been made?

8. Is the water supply line shut
off valve installed and electrical
wiring properly connected?

FINAL INSTALLATION

9. Check all refrigerant lines
and conduit lines, to guard
against vibration or rubbing and
possible failure.

10. Have the bin and cabinet
been wiped clean?

11. Has the Manufacturers
Registration form been properly
filled out? Check for correct
model and serial numbers from
Serial nameplate, then mail to
the SCOTSMAN factory.

12. Has the owner/user been
given the Service Manual and
instructed how to operate and
maintain the icemaker?

13. Has the owner been given
the name and telephone
number of the authorized
SCOTSMAN Service Agency
serving him?

PRECHARGED

LINES

CONNECTED

HAND SHUT

OFF VALVE

BIN DRAIN

April, 1993

Page 10

INITAL START UP

TIMER

FREEZE

PORTION

MCM1462R

Before Start Up:

1. Check that the ICE-OFF-WASH rocker switch
and the COMPRESSOR ON-OFF toggle switch
are in the OFF position, on the control box.

2. Switch on the electrical power. Electrical power
must be supplied to the ice machine for 12 hours
before starting the compressor for the first time.

The crankcase heater will now heat the
compressor’s oil. The oil is warmed to evaporate
any refrigerant that may have collected in it. If
there is refrigerant in the oil when the compressor
starts, the oil will foam and will not lubricate the
compressor properly, shortening its life.

Do NOT start the compressor for the first time
unless the dome of the compressor is warm.

Start Up

1. Remove front panel by removing screws at the
base and pulling out.

2. Remove two screws and the control box cover.

3. OPEN the water supply line shut off valve.

FRONT VIEW OF TIMER

ACTUATOR

BUTTON

CAM

MICROSWITCH

HARVEST

PORTION

4. Open the “king” valve on the receiver.

5. Inside the control box is the shaft of the timer
and the switch assembly. Rotate the shaft of the
timer and switch assembly clockwise to start the
timer. The timer starts when the actuator arm on
the microswitch drops off outer cam into cam slot.
See “Front View of Timer”.

6. Move the ICE-OFF-WASH to the ICE position.

7. Observe water fill cycle: Water pump operates
and water inlet solenoid valve OPENS, incoming
water flows from the valve through the tubing, the
reservoir fills and excess water is overflowed
through the stand pipe. This continues through the
harvest cycle (about 3 and a half minutes). When
the freeze cycle is started, the timer and relay will
close the water inlet solenoid valve and the water
fill cycle is complete. If the sump is not full, rotate
the timer once again to repeat the harvest cycle.
During any cycle the water pump is moving water
through the tygon tubes, up to the water distributor
at the top of each evaporator plate, where water is
uniformly dispensed and cascades down both
sides of the evaporator plates and drains back into
the sump assembly for recirculation.

8. When the sump has filled, move the compressor
ON-OFF toggle switch, to the ON position.

CONTROL BOX

CUBE SIZE

CONTROL

ICE/OFF/WASH

April, 1993

Page 11

MCM1462R

INITAL START UP

9. Check operation of the freezing cycle: The
compressor is operating.The icemaking process
begins; feeling the metal parts of the evaporator
plate reveals cold temperature, very shortly ice
begins to form. Tubing will become frosted at the
top of the evaporator plate. Freezing time will
range between 12 and 15 minutes. Longer time for
temperatures above 70 degrees F. and shorter
time required whentemperatures are below
70-degrees F. Average complete cycle time is
about 14 minutes.

10. Check Cube Size
There is exactly enough water available in the

reservoir to make one full sized batch of cubes.
The water pump may pick up some air at the end
of the freezing cycle: this is normal. If the water
pump runs out of water before the end of freeze,
the cube size control may be set too cold, or the
water system may be leaking water.

To produce SMALLER sized ice cube:

CUBE SIZE DIAGRAM

JUST RIGHT

When the cubes are the correct size,

they will be connected together

vertically, and drop off in strips.

Make them as large as the reservoir

water available will allow.

TOO SMALL

Locate cube size control knob, in the front of the
control box. Rotate one eighth of a turn
COUNTER Clockwise. Observe size of the ice in
the next ice cube harvest and adjust in one eighth
turn or less increments, until correct ice cube is
achieved.

CONTROL BOX

To produce LARGER ice cube:
Locate cube size control on the front of the control

box Rotate screw head one eighth of a turn
Clockwise. Observe size of ice cubes in the next
cube harvest and adjust in one eighth turn or less
increments, until correct ice cube size is achieved.

11. Bin Ice Level Control Operation: With the
icemaker in the harvest cycle, place something
directly below the transducer socket. The machine
should switch off at the END OF THE HARVEST
CYCLE. Within seconds after removal of the
obstruction, the icemaker will restart. This control
has four postions, full, three quarters, one half, and
one quarter. It will not fill up closer than 8" from the
bottom of the ice machine, and will not work on
bins taller than 8’. Note: Even when full the unit will
make one batch of ice when the ICE/OFF/WASH
switch is moved from ICE to OFF to ICE.

12. Replace control box cover and all cabinet
panels and screws.

BIN ICE LEVEL

SWITCH

CUBE SIZE

CONTROL

April, 1993

Page 12

13. Explain to the owner/user the significant details
of the icemaker; start up, operation, and the
cleaning instructions. Answer all questions about
the icemaker by the owner; and inform the owner
of the name and telephone number of the local
authorized SCOTSMAN Distributor, or service
agency.

FREEZING CYCLE OPERATION

MCM1462R

Water from the sump assembly is pumped to the
water distributor system at the top of each
evaporator plate. From the water distributor the
water cascades by gravity over all cells of the plate
and to the sump assembly below.

At the beginning of the freezing cycle, the electrical
circuit is completed to the compressor and the
water pump. The water pump operates
continuously, through both the freezing cycle and
the harvest cycle.

During the freezing cycle, the hot gas solenoid
valve is CLOSED and the water inlet solenoid
valve is CLOSED. When the ice cubes are partially
formed, the cube size control will sense the
temperature at which it is preset to CLOSE. This
will complete the electrical circuit to the timer. The
timer then controls the remainder of the freezing
cycle. The timer will keep the icemaker operating
in the freezing cycle for a selected length of time.
This will give the ice cubes time to fully form. after
that selected length of time, the timer will switch
the icemaker into the harvest cycle, through the
contacts of the timer assembly microswitch.

Low Temperature Freeze:

When the outside air temperature is low, the Head
Pressure Regulator will close off the liquid line to
the receiver, causing liquid refrigerant to back up
into the condenser unitl the head pressure builds
up to 220 PSIG. While this is occuring, the head
pressure regulator passes discharge gas into the
receiver to keep the refrigerant flowing.

WATER DISTRIBUTION

INLET

WATER

VALVE

DRAIN

RESERVOIR

WATER SCHEMATIC

REFRIGERATION SCHEMATIC

April, 1993

Page 13

MCM1462R

HARVEST CYCLE - HOT GAS BYPASS

When the timer switches the icemaker into the
harvest cycle, high pressure, high temperature gas
refrigerant being discharged from the compressor
is diverted from the condenser through the hot gas
solenoid valve into each evaporator plate. During
this cycle, the refrigerant bypasses the condenser.
ln the electrical circuit, both the compressor and
the water pump are operating and the hot gas
solenoid valve is energized and OPEN and the
water inlet solenoid valve is OPEN.
The finished ice cubes are released from the sides
of each evaporator plate by the warming effect of
the hot gas condensing in each evaporator plate
and the water cascading over the ice cubes. The
released ice cubes drop into the ice storage bin
below. At the end of the harvest cycle, the timer
cam will push the actuator arm to the microswitch
IN. If the ice level control is still CLOSED, a whole
new cycle will begin. If the ice level control is
OPEN, the icemaker will begin to shut OFF.

Pump Down Cycle:

When the ice level control is open at the end of the
harvest cycle, power is removed from the liquid
line valve coil, and the pump down cycle begins.
The compressor will continue to run until the pump
down control, sensing low side pressure, opens at
20 PSIG.

WATER

DISTRIBUTION

INLET

WATER

VALVE

DRAIN

RESERVOIR

WATER SCHEMATIC

REFRIGERATION SCHEMATIC

April, 1993

Page 14

COMPONENT DESCRIPTION

TIMER &
SWITCH

MCM1462R

Cube Size Control

This reverse acting thermostat controls the length
of the freezing cycle. It is sensing the temperature
of the suction line. When the suction line gets cold
enough, the cube size control closes (on
temperature fall) and starts the timer. A change in
either ambient air or incoming water temperature
will affect the efficiency of the refrigeration system,
and this will vary the length of time it takes the
evaporator to reach the temperature at which the
cube size control is preset to close. See CUBE
SIZE ADJUSTMENT BEFORE attempting to
adJust the control.

Relay

The multi-function, three pole, double throw,
plug-in relay is installed directly into a receptacle
on the printed circuit board in the control box. The
relay functions in part to by-pass the bin
thermostat control to prevent the icemaker from
shutting OFF, when the bin thermostat opens
during the freezing cycle. The bypass action
serves to ensure full-sized ice cubes with each
harvest cycle.

Timer - Timer & Switch Assembly

The function of the timer begins when activated by
the cube size control. The outer surface, or large
diameter lobe of the timer cam, determines the
timer cycle for finish freezing of the ice cubes,
while the inner surface, or small diameter lobe,
determines the time cycle for the harvest cycle.

When the microswitch button is pushed in there is
power connected to the coil of the relay, and the
unit is in the freeze cycle. When the microswitch
button is released, the power to the relay is
stopped, and the unit goes into harvest. The
microswitch is actuated by a cam assembly
directly connected to the timer motor.

One complete rotation of the cam will take eight
minutes. Harvest is preset at three and one half
minutes, but is adjustable.

High Pressure Safety Control

This is a manual reset control that shuts down the
icemaker, should the discharge pressure ever
reach 400 PSIG. Located below the control box.

Low Pressure Control (Pump Down)

CONTROL BOX

This pressure control connects power to the
compressor contactor coil. Its Cut In is 35 PSIG
and its Cut Out is 20 PSIG. Located below the
control box.

CUBE

SIZE

CONTROL

RELAY

BIN ICE LEVEL

SELECTOR SWITCH

April, 1993

Page 15

MCM1462R

COMPONENT DESCRIPTION

Bin Level Control
This electronic control uses sound waves to

measure the distance between the bottom of the
ice machine and the top of the ice in the bin. It is
designed to control the machine’s ice production to
maintain that distance.

The control is adjustable so that the ice machine
will maintain a certain height of ice. When set at
FULL it will not allow the machine to fill the bin any
closer to the ice machine than about 8", and it will
not work if the distance to the bottom of the bin is
greater than 8 feet.

SONAR SCHEMATIC

ICE/OFF/WASH SWITCH

Because it uses sound waves, a slight “ticking”
sound can be heard coming from the bottom of the
machine.

There are three parts to the control, the
transducer, the circuit board, and the ice level
control switch.

THE USER MAY

SELECT THE

AMOUNT OF ICE TO

BE MAINTAINED IN

THE BIN.

BIN ICE LEVEL

SELECTOR

SWITCH

SOUND WAVES

8"

FULL

3

⁄

4

1

⁄

2

1

⁄

4

April, 1993

Page 16

COMPONENT DESCRIPTION

MCM1462R

Water Inlet Solenoid Valve

The water inlet solenoid valve fills the sump
assembly with water and excess water overflows
out the standpipe and down the drain. This action
fills and rinses the sump during each harvest
cycle. The flow rate is 1 g.p.m.

Water Distribution System

The water distribution system evenly supplies
water to all cells of the evaporator plates. The
water pump pumps water from the sump up the
vertical tygon tube to the tee. From there water is
channeled through the water manifold to the water
distributors, above each evaporator plate, and
from six holes within each distributor, water flows
to the cells of each side of the evaporator plates.
Gravity flow returns the unfrozen excess portion of
water to the sump reservoir for recirculation.

Hot Gas Solenoid Valve

The hot gas solenoid valve functions only during
the harvest cycle, to divert the hot discharge gas
from the compressor, by passing the condenser,
for direct flow in the evaporator plates to release
ice cubes from the ice cube molds. The hot gas
solenoid valve is installed in a branch of the
discharge line. When the harvest cycle begins the
energized solenoid coil lifts the valve stem within
the valve body, to cause the hot discharge gas to
be diverted to the evaporators.

Strainer

A water strainer is located in the potable inlet water
line before the water inlet solenoid valve. Clean
the water strainer frequently.

SUMP STAND PIPE

OPTIONAL

WATER FILTER

HAND

VALVE

WATER

DISTRIBUTORS

SUMP

PUMP

COMPONENT LOCATION

April, 1993

DRAIN CAP

Page 17

MCM1462R

CLEANING

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

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

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

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

CLEANING: ICEMAKER

1. Remove screws and the front panel.

2. Switch the compressor switch to OFF. Switch

Electrical Shock Hazard.
Electrical shock can

cause personal injury.
Cleaning procedures are

done with the power ON.

7. Pour the cleaning solution into the reservoir until
full.

8. Move the master switch to the WASH position.

9. Let the unit operate for 30 minutes.
During the wash cycle, if the machine runs out of

solution, mix 2 more gallons of solution per step 6,
refill the sump and continue the wash cycle for the
remainder of the 30 minutes.

10. Move the ICE-OFF-WASH switch to the OFF
(center) position.

11. Remove the cap and drain the cleaning
solution from the sump. Replace the drain cap.

the ICE-OFF-WASH rocker switch to OFF.

3. Remove the control box cover, and rotate the
shaft of the timer and switch assembly
CLOCKWISE advancing to the freezing cycle.
(Beginning of the higher part of the cam against
the microswitch).

4. Open the ice storage bin door and discard all
the ice.

5. Remove the hose clamp, rubber cap and drain
all the water from the sump assembly into the bin.

Replace the rubber cap and hose clamp.

6. Mix 24 ounces of Scotsman Ice Machine
Cleaner with 2 gallons of warm (95
water.

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.

0

F. - 1150F.)

12. Rotate the shaft of the timer and switch
assembly CLOCKWISE to the harvest position
(low part of the cam against microswitch). Move
the ICE-OFF-WASH switch to the ICE position to
start the Harvest cycle.

If after completing this procedure one or more
evaporator plates does not have a full flow of water
for each vertical column of cubes, shut down the
operation and remove and clean all water
distributor manifolds. Reinstall the water distributor
manifolds.

Note: The ice making portion of the water system
should be sanitized after cleaning by repeating
steps 2-12 and substituting a sanitizing solution for
the cleaning solution.

13. Move the compressor switch to the ON
position to start the icemaking process.

///////////////////////////////////CAUTION///////////////////////////////
DO NOT use ice produced from the cleaning

solution. Be sure none remains in the bin.
///////////////////////////////////////////////////////////////////////////////////

14. Check the next ice cube harvest to be certain
that the ice cubes are clear and the acid taste is
gone.

15. Add hot water to the bin to melt the ice.

16. Replace all panels.

April, 1993

Page 18

CLEANING

MCM1462R

Remote Condenser

1. Shut off the ice machine.
The fan blade can cause

personal injury.
Disconnect power

before beginning to
clean condenser.

2. Remove dirt and debris that might be under the

condenser.

3. Brush off the bottom of the condenser fins. Do

not use a wire brush.

4. Check to see that the inside of the condenser is

clean; light should be visible through the fins. If
not, clean the internal parts by vacuum, pressure
washer and/or coil cleaner.

Ice Storage Bin

The interior liner of the bin is in contact with a food
grade product: ice. The storage bin must be
cleaned regularly to maintain a sanitary
environment. Once a week cleaning with soap and
water, a hot water rinse and and air dry is a basic
procedure. Scale that may form on the plastic liner
of a bin may be removed by scrubbing the surface
of the line with a mixture of Scotsman Ice Machine
Cleaner and hot water. Remove any scale prior to
sanitizing.

To remove scale:

1. Mix a cleaning solution of 4 ounces of Scotsman
Ice Machine Cleaner to 4 pints of hot (95

0

110

F.) water.

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.

2. Remove all ice from the bin.

3. Using rubber gloves, dip a nylon scouring pad
into the cleaning solution, and scub the scale off of
the liner.

4. After the scale has been removed, rinse all of
the surfaces inside the bin with clean, potable
water.

To sanitize the bin and ice machine:

0

F. to

Follow local codes for frequency of sanitizing. Use
an approved sanitizer and follow the directions and
warnings of that santitizer or use the following
instructions for use of household bleach, if it meets
local codes:

1. Remove all ice from the bin.

2. Mix a sanitizing solution of 1 ounce of
household bleach to 2 gallons of water.

3. Using clean rubber gloves and a clean cloth,
wipe all interior surfaces of the ice machine and
ice storage bin with the sanitizing solution.
Immerse any small parts in the sanitizing solution
and wash the parts, flushing the solution
thoroughly in, over and through all parts and
surfaces of the parts being cleaned.

4. Allow to air dry.

April, 1993

Page 19

MCM1462R

SYSTEM SPECIFICATIONS

The following numbers can be used as a guideline when servicing the CMS1402. There will be some
variation from unit to unit, so allow for that.

THIS MACHINE USES REFRIGERANT 22

Components:
Timer, 1 revolution of the cam takes 8 minutes, harvest time is factory set at 3
Inlet water valve, water flow in g.p.m. = 1

CUT IN CUT OUT

0

Cube size control, reverse acting temperature range . . . . . . . (0

High pressure safety, Manual . . . . . . . . . . . . . . . . . . . 400

Bin or Ice Level Control

Maximum Full Height: . . . . . . . . . . . . . . . . . . . . 8" from the base of the ice machine

Maximum Storage Bin Interior Height . . . . . . . . . . . . 8 feet from the base of the ice machine

F. to +250F.)

Characteristics:

Freeze Cycle (90/90/70)

Average Discharge Pressure . . . . . . . . . . . . . . . . . . . . 270 - 240 PSIG

1

⁄2 minutes, but is adjustable.

Average Suction Pressure at the end of freeze . . . . . . . . . . . 22 - 24 PSIG

Average Amps . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Average Freeze Cycle Time . . . . . . . . . . . . . . . . . . . . 15 minutes

Harvest Cycle

Average Discharge pressure . . . . . . . . . . . . . . . . . . . . 180 - 200 PSIG

Average Suction Pressure . . . . . . . . . . . . . . . . . . . . . 75 80 PSIG

Average Amps . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.6 (3 phase)

Average Harvest Time . . . . . . . . . . . . . . . . . . . . . . . 2.25 minutes

Refrigerant Charge: 16 lbs. of R-22. If the nameplate charge is different, go by the nameplate.

April, 1993

Page 20

ADJUSTMENTS

Electrical power present
in the control box can
cause personal injury.

Disconnect power before
beginning to adjust timer.

Adjustment Of The Timer & Switch Assembly

One complete revolution of the cam on the timer
takes eight minutes. The normal setting is three
and one-half minutes, as set at the factory. lt is
important that the length of the harvest cycle allow
enough time for all the ice cubes to fall from the
evaporator. Too short of a time will cause the
evaporator to freeze up and stop ejecting ice into
the bin. Too much time wastes icemaking capacity,
energy and water. Adjustment of the harvest cycle
may require a corresponding adjustment of the
cube size control. Rotating the shaft of the timer
cam clockwise will allow putting the machine into
either the freezing cycle or harvest cycle, as
required in the cleaning instructions.

MCM1462R

MICROSWITCH

To Adjust The Timer & Switch Assembly:

The length of the harvest cycle can be changed by
loosening the set screw on the cam, and then
rotating the shaft so that the opening between the
cams change. More of an opening between the
cams = more harvest time. The harvest time may
be reduced if not needed. This will yield more ice
per day.

CLOSE UP

VIEW OF TIMER

SWITCH

ACTUATOR

CAM

ADJUSTING TIMER

TIMER

CAM

April, 1993

Page 21

MCM1462R

SERVICE DIAGNOSIS: Water

SYMPTOM POSSIBLE CAUSE PROBABLE FIX

No ice is made Inlet water valve will not open or is

dirty
No water being pumped over

evaporators.

Water inlet valve leaks thru at high

rate
Cubes are not uniform in shape Water distributors are dirty Clean water system
Long Freeze Cycle Inlet water valve leaks through Replace inlet water valve

See electrical/adjustment See electrical/adjustment
Makes thick ice/freezes up Water inlet valve restricted Clean or replace valve

Low water pressure Check water filter or supply

Sump covers out of position Re-position sump covers
Cubes too large Inlet water valve leaks through Replace inlet water valve

See electrical/adjustment See electrical/adjustment
Low Capacity Incoming water very warm Check water temperature to building

Lack of water See unit runs out of water
Unit runs out of water Reservoir leaks Repair leak

Inlet water valve restricted Clean or replace valve

Short harvest cycle Adjust timer

Water pressure too low Check supply

Clean inlet screen, check coil,
replace valve if required

Check pump motor, replace pump if
motor will not run.

No water in reservoir, check inlet
water valve, check reservoir for leak.

Replace inlet water valve

April, 1993

Page 22

MCM1462R

SERVICE DIAGNOSIS: Electrical and/or Adjustments

SYMPTOM POSSIBLE CAUSE PROBABLE FIX

Machine does not operate No power Reconnect power

High pressure control open Reset, check machine

High temperature cut out open Hot gas valve leaks thru, replace

P. C. Board Open Replace board

Master switch open Test/replace

Timer contacts open Replace timer

Bin ice level control holding machine

off
Makes thick ice/freezes up Harvest Cycle too short Adjust timer

Low water pressure Check water filter or supply

Hot gas valve defective Replace hot gas valve

Sump covers out of position Re-position sump covers

Cubes too small Adjust cube size

Cube size control stuck open Replace cube size control
Runs, makes no ice Pump problem or water leak in

reservoir

Water inlet valve either lets in no

water or leaks through

Timer stuck Replace timer

Relay does not energize; unit stuck in

harvest
Long freeze cycle Water inlet valve leaks through Replace inlet water valve

Water temperature too high Advise user
Cubes too small Cube size set wrong Adjust cube size

Cubes size control stuck closed Replace cube size control
Cubes too large Water inlet valve leaks through Replace inlet water valve and adjust

Compressor cycles on and off on
pump down control

Compressor will not run Low pressure control will not close Check pump down control for proper

Unit cycles on and off anytime in any
cycle

Low refrigerant charge Locate leak, repair, replace drier,

Liquid line valve or drier restricted Check and replace

TXV restricted Check and replace

Head pressure control valve not

working (low condensing temp.)

Contactor coil open Check/replace contactor

Compressor windings open Check replace compressor

Loose connection in PC board Replace PC board

See page 24

Check water system and pump

Replace inlet water valve

Replace relay

cube size control

evacuate and weigh in nameplate
charge.

Check/replace head pressure control
valve

operation

April, 1993

Page 23

MCM1462R

SERVICE DIAGNOSIS: Refrigeration and/or Mechanical

SYMPTOM POSSIBLE CAUSE PROBABLE FIX

Poor harvest Hot gas valve does not open Check for power to the coil, check for

not opening, replace

Head pressure control valve does not

maintain enough head pressure.
Unit cycles off during freeze or

harvest
Low capacity High head pressure, from dirty

Unit shuts off before bin is full Bin Ice level control is set to “Partial” Move bin Ice level rocker switch to

Compressor cycles on and off Low pressure control opening and

Frost on compressor Some frost will not hurt Do nothing

Hi temperature switch opens and

closes

condenser, faulty fan motor

Non condensable gas in the system Purge system, evacuate and weigh in

Extreme hot location Relocate the cabinet

Overcharge of refrigerant Evacuate and weigh in nameplate

Hot gas valve leaks thru At the end of the freeze cycle there

Liquid and discharge lines are in

contact with each other

closing

Compressor overheats TXV not letting enough refrigerant

TXV meters too much refrigerant Adjust or replace TXV

Replace head pressure control valve.

Hot gas valve leaks thru, replace it

Clean condenser, repair fan motor

nameplate charge

charge

should be frost on the evaporator end
of the hot gas tubes, if not replace the
hot gas valve

Separate and insulate them

“Full”.
Check low side pressure, liquid line

valve must open and low side
pressure raise over 35 PSIG before
pump down control will close to run
compressor

into evaporators, adjust or replace
TXV

Mechanical fault with compressor,
replace compressor

April, 1993

Page 24

Electrical Shock Hazard
Can Cause Personal Injury.

Disconnect Power Before
Servicing.

Bin Thermostat Posts at
Line Voltage.

MCM1462R

SERVICE DIAGNOSIS: Bin Ice Level Control

CONDITION DETERMINE CAUSE PROBABLE CORRECTION

Ice Machine does not run, it has
power to it, the high pressure control
is closed, the on/off switch is set to
ON (the compressor will not operate
until the liquid line valve opens, but
the pump should be working if there
is no ice in the bin).

Machine runs, makes ice, switches
on and off, but ice level cannot be
controlled.

Machine runs, but will not shut off. Board relay stuck closed. Check

A. Listen for a ticking sound from

transducer.

B. Remove front panel(s), twist

transducer 1/4 turn and pull out. DO

NOT UNPLUG with power

connected. Examine the transducer,

the inside must be clean and dry.

C. Check power to bin level control

board.

D. Disconnect electrical power and

test ice machine circuit by attaching a

jumper wire between bin thermostat

posts on circuit board part no.

12-1912-01 (the circuit board with the

timer on it). Reconnect power.

E. Transducer or ice level board

assembly defective.

Ice level switch may be defective. On

boards with a light, check by moving

switch & watching light.

relay.

If no noise, go to C. If there is a
noise, check for a light on the board
(models built after 4/93). If there is a
light on, check relay contacts N.O.
and COM. The contacts should be
CLOSED. If closed, go to D. If not,
replace the board. If light is off, or
prior model, go to B.

If the inside of the transducer (above
screen) was wet, replace it. Set bin
level to FULL and aim at an object
about 1-3 feet away. Machine should
restart, if not go to D.

Should be 12 volts from transformer,
if not replace transformer. If there is
power go to D.

If machine does not start go back to
machine circuit. If machine starts,
disconnect electrical power, remove
jumper wire and reconnect electrical
power. Then go to E.

Replace transducer. Set bin level to
FULL and aim at an object about 1-3
feet away. Machine should restart. If
this does not repair unit, replace the
board.

Replace ice level switch

If COM and N.O. are closed when
power is off, replace board. If open,
go to B above.

PARTIAL
VIEW OF
CIRCUIT

BOARD

12-1912-01

TIMER

PLUG - IN

RELAY

BIN THERMOSTAT

POSTS MENTIONED IN

“D” ABOVE

April, 1993

Page 25

NOTCH IN BACK OF

CONTROL BOX

MCM1462R

REMOVAL AND REPLACEMENT

Cube Size Control

To remove the cube size control:

Electrical Shock Hazard.
Electrical shock can

cause personal injury.
Disconnect power

before beginning to
service components.

Water Distributor Tubes And Manifold Tubes
To remove the water distributor tube and manifold

tube:

1. Remove the front panel.

2. Slide the water distributor tube to the front about
1/8-inch along the top of the evaporator plate, until
the water distributor tube can be unsnapped from
the flexible notch and lifted upward.

WATER DISTRIBUTOR

1. Remove front panel.

2. Remove cover from control box.

3. Trace capillary tube, from the cube size control
to the refrigerant suction line.

CUBE SIZE

CONTROL

REPLACEMENT OF THE CUBE SIZE CONTROL

3. Unsnap and disconnect water distributor tubes
from the water manifold section. To replace the
water distributor tubes and manifold tubes, reverse
the removal procedure. BE SURE the notches in
the water manifold tubes properly engage the
alignment keys in the tee. BE SURE the water
distributor tube is securely fastened at the notch at
both sides of the evaporator plate. Check identical
attachment for the left water distributor tube and
notch; also, that the distributor/manifold
connections at the top center of each evaporator
plate is snug against the top of the plate.

4. Remove the coiled capillary tube bulb from the
tube well on the suction line.

5. Remove electrical leads from the cube size
control.

6. Remove screws and pull the capillary tube
through the notch in the back of the control box.
Remove the cube size control. To replace the cube
size control, reverse the removal procedure.

April, 1993

Page 26

REMOVAL AND REPLACEMENT

MCM1462R

Inlet Water Solenoid Valve Assembly

To remove the inlet water solenoid valve assembly:

Electrical Shock Hazard.
Electrical shock can

cause personal injury.
Disconnect power

before beginning to
service components.

Water Pump

1. Remove front panel.

2. Unplug water pump electrical connection.

3. Drain water reservoir.

4. Use corbin clamp pliers to loosen and slide
corbin clamps on hoses away from pump.

5. Remove screws retaining pump to bracket.

6. Pull pump out of ice machine.

7. Reverse to reassemble.

8. Replace front panel.

8. Reconnect electrical power.

1. Shut OFF water supply to machine.

2. Loosen and remove outlet water line from the
inlet water solenoid valve assembly.

3. Remove screws and pull the water solenoid
valve out to gain access.

INLET WATER

VALVE

STRAINER

REMOVAL OF THE

INLET WATER VALVE

Transducer

1. Disconnect electrical power BEFORE removing
transducer.

2. Remove the front panel and locate the
transducer socket.

3. Twist inner portion of transducer
counter-clockwise and push up gently.

4. Unplug transducer and remove from the
machine.

5. Reverse steps 1-4 to reassemble.

4. Pull electrical cord from solenoid coil terminals.

5. Remove inlet water fitting from the water
solenoid valve. To replace the inlet water valve
assembly, reverse the removal procedures.

Bin Ice Level Control Circuit Board

1. Disconnect Electrical Power before removing
circuit board.

2. Remove front panel.

3. Remove control box cover.

4. Remove wires from circuit board connections.

5. Unlock circuit board fasteners by twisting 1/2
turn.

6. Pull circuit board of off fastener posts.

7. Reverse to reassemble, refer to wiring diagram
as needed.

April, 1993

Page 27

MCM1462R

REFRIGERATION SERVICE

General:

••Scotsman recommends that any work on the

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

••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 wasted to the

atmosphere, but recovered.

••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.

••When brazing the tubing connections to the hot

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

Specifically:

Recover, reclaim or recycle refrigerant. The
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. Reclaim programs are available thru
most refrigerant wholesalers.

Use conservation minded service procedures:

••Refrain from checking refrigeration pressures

without reason. There are many 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.

••If gauges must be used, do not 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 much more
important on an ice machine than is the high
side.

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

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

••If hi side pressure must be checked, use a

quick connect at the end of the discharge hose
to minimize the release of refrigerant, J/B
Industires part number A33000 works well.

••Scotsman’s schrader valve caps must be

tightened to 70 inch - pounds to insure that the
valves will not leak.

••If using recycled refrigerant, it must meet ARI

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

If the refrigeration system must be serviced, the
quality of service must insure that there will not be
a repeat failure, as repeat failures will cause
refrigerant to be discharged into the air by the
failure or when the failure is corrected:

••If there has been a compressor burn out, check

for acid in the oil. If acid is indicated, extra steps
must be taken to clean up the system.

••Never use refrigerant, such as R-11, to clean

up or flush out a refrigeration system. When
system clean-up is required, the use of suction
line filter-dryers and liquid line filter-dryers are
recommended.

••Always replace the dryer when repairing a leak

or replacing a refrigeration component.

••Evacuate the system with a good vacuum

pump to 500 microns or less. If the triple
evacuation method is used, the vacuum should
be broken each time with dry nitrogen, not
refrigerant. Evacuation must be from both sides
of the system.

••Weigh in or measure in the nameplate charge.

Recharge into the high side.

••Check for leaks with a high quality, electronic

leak detector. Halide torches will not locate the
very small leaks.

••Scotsman’s schrader valve caps must be

tightened to 70 inch - pounds to insure that the
valves will not leak.

If an ice machine is to be discarded and still
contains refrigerant, Scotsman recommends that
the refrigerant be recovered, reclaimed, or
recycled so that it is not discharged into the air.

April, 1993

Page 28

SERVICE PORT

REMOVAL AND REPLACEMENT

MCM1462R

Thermostatic Expansion Valve

1. Before replaceing this valve, be certain that the
valve is the cause of the problem, and cannot be
adjusted.

2. Remove the front panel.

3. Discharge and recover the refrigerant.

4. Locate the TXV bulb (on the suction line),
remove the clamps and bulb from the tube.

5. With the refrigeration system open, unsweat the
TXV from the tubing.

6. Place the new TXV in position.

7. Wrap the new TXV body with heat sink material.
Do not get any moisture in the valve.

8. Carefully braze the valve to the tubing. Examine
the joints, if they look good procede to the next
step, if not, re-do them.

9. Install a new dryer, and braze it in place also.

10. Reattach the TXV bulb to the suction line in the
same place as the old one.

11. Evacuate the system to 500 microns.

12. Weigh or measure the nameplate charge into
the receiver.

13. If the machine has been off on the breaker
there may be refrigerant trapped in the oil of the
compressor, so do not restart until the compressor
has been warmed by the crankcase heater for 12
hours. If the compressor was warm throughout the
replacement process, the ice machine may be
restarted without waiting to re-warm the
compressor.

Hot Gas or Liquid Line Valve.

1. Before replaceing this valve, be certain that the
valve is the cause of the problem.

2. Remove the front panel.

3. Discharge and recover the refrigerant.

4. Unplug the coil of the valve.

5. With the refrigeration system open, unsweat the
valve from the tubing.

6. Place the new valve in position.

7. Wrap the new valve body with heat sink
material. Do not get any moisture in the valve.

8. Carefully braze the valve to the tubing. Examine
the joints, if they look good procede to the next
step, if not, re-do them.

9. Install a new dryer, and braze it in place also.

10. Plug the power cord back onto the coil.

11. Evacuate the system to 500 microns.

12. Weigh or measure the nameplate charge into
the receiver.

13. If the machine has been off on the breaker
there may be refrigerant trapped in the oil of the
compressor, so do not restart until the compressor
has been warmed by the crankcase heater for 12
hours. If the compressor was warm throughout the
replacement process, the ice machine may be
restarted without waiting to re-warm the
compressor.

Refrigerant:
NO liquid refrigerant may be put into this system

anywhere except the receiver. DO NOT use the
Schrader valves at the front of the machine for
weighing in the charge: use the “king” or receiver
service valve. All liquid R-22 must be weighed

into the receiver through the “front seated”
receiver outlet service valve.

FRONT SEATED VALVE

April, 1993

Page 29

MCM1462R

REFRIGERATION SERVICE

General:

••Scotsman recommends that any work on the

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

••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.

••Although this system uses R-22, it should not

be wasted to the atmosphere, but reclaimed.

••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.

••When brazing the tubing connections to the hot

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

Specifically:

Recover, reclaim or recycle refrigerant. The
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. Reclaim programs are available thru
most refrigerant wholesalers.

Use conservation minded service procedures:

••Refrain from checking refrigeration pressures

without reason. There are many 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.

••If gauges must be used, do not 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 much more
important on an ice machine than is the high
side.

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

Minimal refrigerant discharged into the hoses

equals minimal refrigerant discharged into the
air.

••If hi side pressure must be checked, use a

quick connect at the end of the discharge hose
to minimize the release of refrigerant, J/B
Industires part number A33000 works well.

••Scotsman’s schrader valve caps must be

tightened to 70 inch - pounds to insure that the
valves will not leak.

••If using recycled refrigerant, it must meet ARI

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

If the refrigeration system must be serviced, the
quality of service must insure that there will not be
a repeat failure, as repeat failures will cause
refrigerant to be discharged into the air by the
failure or when the failure is corrected:

••If there has been a compressor burn out, check

for acid in the oil. If acid is indicated, extra steps
must be taken to clean up the system.

••Never use refrigerant, such as R-11, to clean

up or flush out a refrigeration system. When
system clean-up is required, the use of suction
line filter-dryers and liquid line filter-dryers are
recommended.

••Always replace the dryer when repairing a leak

or replacing a refrigeration component.

••Evacuate the system with a good vacuum

pump to 500 microns or less. If the triple
evacuation method is used, the vacuum should
be broken each time with dry nitrogen, not
refrigerant. Evacuation must be from both sides
of the system.

••Weigh in or measure in the nameplate charge.

Recharge into the receiver.

••Check for leaks with a high quality, electronic

leak detector. Halide torches will not locate the
very small leaks.

••Scotsman’s schrader valve caps must be

tightened to 70 inch - pounds to insure that the
valves will not leak.

If an ice machine is to be discarded and still
contains refrigerant, Scotsman recommends that
the refrigerant be recovered, reclaimed, or
recycled so that it is not discharged into the air.

April, 1993

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