INTRODUCTION
NM1250R
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 NM1250R is a remote condenser modular
ice system that produces up to 1400 lbs. of
nugget ice in 24 hours at 90
water.
0
F. air and 700 F.
It features: front service for the freezer,
gearmotor, control box, water reservoir, and
bin control; stackable with kit KSTACK30; an
electronic circuit for monitoring ice and water
level; a thermostatic expansion valve; and
R-502 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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Component Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Maintenance & Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Service Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Removal and Replacement
Water Reservoir & Bin Controls . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Bearing & Breaker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Auger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Watert Seal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Evaporator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Gearmotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Circuit Board Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Parts Lists and Wiring Diagrams are located in the center of this manual, printed on yellow
paper.
November, 1988
Page 1
BASIC
ELECTRICAL
208-230/60/1
208-230/60/3
MINIMUM
CIRCUIT
AMPACITY+
9.5
na
NM1250R
FOR THE INSTALLER
The NM1250R is designed to fit the following
Scotsman storage bins:
B590 and extensions (with bin top KBT18)
HTB500 or BH500
BH800 using bin top KBT15
BH1000 using bin top KBT16
When installing a new system, check to be
sure that you have everything you need
Correct Condenser
Correct Bin
Correct Ice Machine
Correct Bin Top (if required)
Correct Precharged line set
Fan Relay kit (if needed)
All kits, legs, and information required for the
specific job.
before beginning:
SPECIFICATIONS: ICEMAKER
MODEL DIMENSIONS
(without bin)
H" x W" x D"
NM1250RE-32A
NM1250RE-3A
27 x 30 x 24
same
COND.
TYPE
REM0TE-
AIR
COMP.
H.P.
1.75
same
ICE
TYPE
NUGGET
same
+ Minimum Circuit Ampacity is used to determine wire size per National Electric Code.
The standard finish is enamel sandalwood. A stainless steel panel kit, SPKCMD-1, may be field
installed to convert the unit to a stainless steel finish.
November, 1988
Page 2
MAXIMUM
FUSE
SIZE
20
na
FOR THE INSTALLER
24"
32"
5"
NM1250R
1.19"
Typical Storage Bin: BH800
Back View
21"
Drain
3/4"
FPT
4.56"
Side View
14.69"
22.38"
31.5"
Installation Limitations:
This ice system is designed to be installed indoors,
in a controlled environment:
Min Max
Air Temperature 50
Water Temperature 40
Water Pressure 20 psi 80 psi
Voltage 5% +10%
(Compared to the nameplate)
The temperature limitations do not apply to the
remote condenser. It will work between -20
degrees F, and 120 degrees F.
Operating the machine outside of the limitations is
misuse and can void the warranty.
Scotsman Ice Systems are designed and
manufactured with the highest regard for safety
and performance. They meet or exceed the
standards of UL, NSF, and CSA.
Scotsman assumes no liability or responsibility of
any kind for products manufactured by Scotsman
that have been altered in any way, including the
use of any part and/or other components not
specifically approved by Scotsman.
Scotsman reserves the right to make design
changes and/or improvements at any time.
Specifications and design are subject to change
without notice.
0
F 1000F
0
F 1000F
Front View
42"
44"
6"
November, 1988
Page 3
32.56"
NM1250R
FOR THE INSTALLER: Remote Condenser
1/2" MALE QUICK CONNECT
COUPLING FOR USE WITH RT625
OR RT640 PRECHAGED LINE SET
22"
5.75"
19.88"
5.38"
27.81"
7.94"
5"
3.5"
6.5"
LIQUID LINE 3/8" MALE QUICK CONNECT
7.5"
COUPLING FOR USE WITH RT625 OR
RT640 PRECHARGED LINE SET
SPECIFICATIONS: REMOTE CONDENSER
MODEL DIMENSIONS
H" x W" x D"
RC1051-32A
RC1052-32A
27.81" x 22" x 37.94"
same
USE WITH BASIC
ELECTRICAL
1 NM1250R
1 or 2 NM1250Rs
208-230/60/1
same
MINIMUM CIRC.
AMPACITY+
2
same
SHIPPING
WEIGHT
84 lbs.
same
+ Included with minimum circuit ampacity for the icemaker. Use this valve to determine wire size
and type between ice maker and fan motor.
RT625 Precharged line set, 25’. R502.
RT640 Precharged line set, 40’. R502.
KCMR230 Fan relay kit used when two icemakers are on one two circuit condenser.
ICEMAKER NAMEPLATE
LOCATED ON BACK PANEL
SERIAL PLATE LOCATED
BEHIND FRONT PANEL
November, 1988
Page 4
FOR THE INSTALLER
LEVEL THE ASSEMBLY
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.
NM1250R
Storage Bin:
Tip the storage bin on its back, using
parts of the carton to protect the exterior
finish. Install the legs into the threaded
holes in the bottom of the bin. Turn the
leg levelers all the way in preparation
for leveling later. Return the bin to the
upright position, remove paper covering
the bin gasket.
Install bin top if required, follow the
directions included 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, left, and right sides. Secure
the machine to the bin with the
hardware provided with the machine.
Remove the front panel and remove the
styrofoam shipping blocks from under
the gearmotor, the top of the ice chute, and
from between the gearmotor and the right side
panel.
HARDWARE SUPPLIED
GASKET
FASTEN THEMACHINE
TO THE BIN WITH THE
WITH THE ICEMAKER
November, 1988
Page 5
LOCATE REMOTE
CONDENSER
ABOVE ICEMAKER
NM1250R
FOR THE INSTALLER: Remote Condenser Installation
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
highest (if stacked) 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.
//////////////////////////////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.
REMOTE CONDENSER
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.
SPIRAL
EXCESS
TUBING
INSIDE
BUILDING
November, 1988
Page 6
FOR THE INSTALLER
SERVICE PORTS
REMOTE
CONDENSER
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, then using two wrenches (it is important
that ONLY the nut on the precharged lines be
turned, the other parts of the couplings must
NOT be allowed to turn or the process will tear
out the diaphragms and they will be loose in
the refrigeration system) tighten the coupling
until it bottoms out or a definite increase in
resistance is felt.
4. Using a marker or pen, mark a line
lengthwise from the coupling union nut to the
bulkhead. Then tighten the coupling and
additional 1/4 turn. As the nut turns, the line
will show when 1/4 turn is made.
NM1250R
5. Connect the 3/8 inch liquid line (schrader
valve end) to the remote condenser fitting
marked "liquid line".
6. Connect the other end of the liquid line to
the icemaker fitting marked "liquid line."
7. Connect the 1/2 inch discharge line
(schrader valve end) to the remote condenser
fitting marked "discharge line".
8. Connect the other end of the liquid line to
the icemaker fitting marked "discharge line".
9. After all connections are made, and after
the king valve has been opened, check the
couplings for leaks.
SCHRADER VALVE
TO REMOTE
CONDENSER
NO SHRADER
VALVE
TO ICEMAKER
3/8" LIQUID LINE
1/2" DISCHARGE LINE
November, 1988
Page 7
NM1250R
FOR THE INSTALLER: Stacking
////////////////////////////WARNING///////////////////////////
ELECTRICAL POWER MUST BE OFF
WHEN CONNECTING WIRES
/////////////////////////////////////////////////////////////////////////
1. Install the lower unit onto the bin.
2. Remove the top panel from the lower unit.
3. With the aid of a mechanical hoist, lift the
upper machine onto the top of the lower unit.
Align the rear, left, and right side panels.
4. Secure the bottom machine to the top
machine with the hardware provided with the
top unit: 4 cap screws, and 2 metal straps.
5. Use stacking kit KSTACK30:
a) In the lower unit, remove the ice chute
cover.
b) In the upper unit, temporarily remove the
ice discharge chute.
c) In the lower unit, insert the chute from the
kit into the hole in the base of the upper unit,
temporarily push it up into the base.
d) In the lower unit, install the new ice chute
cover, then slide the connecting chute down
into the hole in the new cover.
e) In the upper unit, reinstall the ice chute and
cover. Remove the upper unit bin control
sensors from their circuit board connections.
Install the relay from the kit in the location
illustrated.
f) Install interconnecting wires from the kit
between the upper unit circuit board "opto"
(purple wire) and "LED" (yellow wire)
connections and the relay:
Purple to terminal 9.
Yellow to terminal 6.
Install wire harness from lower unit through
the hole in the base, and connect to the relay
terminals A & B.
g) In the lower unit, remove the wire harness
from the transformer to the circuit board.
Connect new wire harness (just routed from
the upper unit) onto transformer and circuit
board.
Replace the front panels.
Note: When started, the lower unit will start
first, then the upper.
November, 1988
Page 8
FOR THE PLUMBER
ICEMAKER DRAIN
3/4" FPT
CONFORM TO ALL APPLICABLE CODES
NM1250R
Water Inlet
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.
WATER
INLET
3/8" FLARE
HAND
SHUT OFF
VALVE
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.
CONNECT TO
COLD WATER
FIELD INSTALLED
BIN DRAIN
3/4" FPT
FILTER
(OPTIONAL)
November, 1988
Page 9
NM1250R
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 terminals for the
compressor and the fan motor
operates whenever the compressor
operates.
Electrical connections are made at the
junction box at the back of the
icemaker and at the junction box on
the remote condenser.
The remote condenser must be wired
to the icemaker in accordance with
local and national electrical codes with
a minimum of 18 Awg. wire with an
ground bonding wire connected to the
ground screws provided in both the
condenser and machine field wiring
boxes. All outdoor wiring must be in
rainproof conduit.
All external wiring must conform to
national, state, and local electrical
codes. The use of a licensed
electrician is required to perform
the electrical installation.
REMOTE CONDENSER
WATERPROOF
(LIQUID TIGHT)
CONDUIT
ICEMAKER
JUNCTION BOX
POWER
SUPPLY
November, 1988
Page 10
FOR THE ELECTRICIAN
NM1250R
FAN RELAY KIT
To install the KCMR230 fan relay kit when
using (2) NM1250R icemakers and one 230
volt, two circuit remote condenser.
//////////////////////////////WARNING//////////////////////////
Do all wiring with electrical power OFF.
//////////////////////////////////////////////////////////////////////////
See the remote condenser nameplate for
current requirements to determine wire size to
be used for electrical hookup. Refer to wiring
diagram.
All external wiring should conform to the
national, state and local electrical codes.
Usually an electrical permit and services of a
licensed electrician will be required.
1. Mount the control box in a convenient
location.
2. Attach a solid earth ground wire to the
ground screw.
3. Route connecting wires from the first ice
maker junction box
(marked condenser fan) and connect it to the
KCMR230 terminal strip marked: NO. 1 ICE
MACHINE.
4. Route connecting wires from the second
machine junction box
(marked condenser fan) and connect it to the
KCMR230 terminal strip marked: NO. 2 ICE
MACHINE.
5. Route connecting wires from KCMR230
terminal strip marked: TO REMOTE FAN and
connect at the remote condenser junction box.
SUGGESTED
LOCATION
FOR KCMR230
CONTROL BOX
November, 1988
Page 11
NM1250R
FOR THE ELECTRICIAN (Do this after Start Up)
6. Check phasing of the electrical circuit as
follows:
A. The phasing of the wiring MUST now be
checked, as incorrect phasing will result in a
failure of the kit relay.
Below is an illustration of the KCMR230
terminal strip. Note that each terminal is
marked: 1-2-3-4-5-6. For proper phasing:
Terminals #1 and #3 must be connected to
the same side of the line (such as L1)
Terminals #2 and #4 must be connected to
the same side of the line (such as L2).
B. Make a test with a volt meter as follows:
1. Switch on icemaker #1 first, then switch on
icemaker #2.
(The compressors must be operating for this
test. Do this after start up.)
2. Test with a volt meter between terminals
#2 and #4, then between terminals #1 and #3.
Compare the readings obtained to the ones in
the following list:
C. Test terminals 1-2 = Full Voltage (208-230)
Test terminals 1-3 = No voltage
Test terminals 2-3 = Full Voltage
Test terminals 2-4 = No voltage
Test terminals 3-4 = Full voltage
Test terminals 1-4 = Full voltage
D. If there is full voltage where there should
be no voltage, turn off icemaker #2, (both
switches) Then turn off icemaker #1 (both
switches). The connections at the KCMR230
terminal strip marked icemaker #1 must be
reversed (put the wire that was on 1 on 2 and
the wire that was on 2 on 1).
November, 1988
Page 12
FOR THE INSTALLER: Completed Installation
A typical installation should generally appear
as illustrated below. The remote condenser
must be located above the icemaker and the
precharged lines installed per the instructions
on page 6.
NM1250R
ROOF
CUT-AWAY
INSULATED PRECHARGED
REFRIGERANT TUBING
November, 1988
Page 13
LEVELED?
NM1250R
FOR THE INSTALLER: Final Check List
1. Is the ice system installed
indoors in a location where the air
and water temperatures are
controlled, and where they do not
exceed the design limitations?
2. Is there an electrical service
disconnect within sight of the
installed machine? Has the
voltage been checked, and
compared to nameplate
requirements?
3. Have all the plumbing
connections been made and
checked for leaks?
4. Has the machine and bin been
leveled?
5. Is there a minimum of 6"
clearance at the rear, left, and right
of the machine for proper service
access and air circulation?
6. Is the water pressure a
minimum of 20 psig?
7. Has the machine been secured
to the bin?
8. If stacked, has the stacking kit
been installed?
9. Is there a water shut off valve
installed near the machine?
10. Is the remote condenser
installed per local building codes,
and in a place where it has
adequate ventilation and minimal
solar heat gain?
11. Has all shipping material
(under and next to the gearmotor,
and on top of the ice chute) and
literature (inside the front panel)
been removed from the units?
12. Have the remote condenser
and precharged lines been
properly installed?
13. Has the electrical connection
between the icemaker and the condenser
been made?
14. Verify that the master switch is in the OFF
postion.
POWER SUPPLY?
PLUMBING?
DRAINS?
15. Switch on the electrical power.
16. Refer to Pre-Start instructions, the next
page.
November, 1988
Page 14
START UP
Pre-Start Inspection
1. Remove the front, left, and right side
service panels.
2. Check that the styrofoam shipping blocks
under the gearmotor, on top of the ice
dischage chute, and between the gearmotor
and the right side panel have been removed.
NM1250R
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 dome is warm.
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 reservoir, fills the tube from
the reservoir to the evaporator, and then shuts
off. Check for leaks.
3. Open the King Valve.
4. Turn the master switch on, and press the
start/reset switch.
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 pump down control will
close and the compressor will start.
6. Check that the unit is installed corerectly
according to the final check list on page 14.
discharge pressure will depend upon air and
water temperatures, but should be between
200 psig and 280 psig.
Gearmotor amps should be about 1.2.
Compressor (single phase) amps should be
about 7.1
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.
5. The remote condenser fan turns, and the
condenser begins to discharge warm air.
6. The unit should soon be making ice, if
desired the low side pressure can be checked,
it should be 30 psig + or - 4 psig. The
November, 1988
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.
Page 15
RESET SWITCH
GEAR MOTOR
EVAPORATOR
ICE LEVEL SENSORS
NM1250R
COMPONENT DESCRIPTION
Control Box: Contains the electrical controls
that operate the machine.
High Pressure Cut Out (control): A manual
reset switch sensing the high side refrigeration
pressure. It is set to shut the machine off at
450 psig.
Reset Switch: Manual reset. Glows when the
unit shuts off from ice discharge chute being
overfilled (opening the microswitch at the top
of the chute), or if either of the pressure cut
out switches opens.
Evaporator: A vertical stainless steel tube,
refrigerated, and water filled. In it there is a
stainless steel auger.
Reservoir: Float operated, it maintains the
water level in the evaporator at a constant
level, it also contains the water level sensor.
Water Level Sensor: Senses if there is water
in the reservoir to make ice out of. Will shut
the machine off it there is none.
Ice 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.
RESERVOIR
WATER LEVEL SENSOR
(INSIDE RESERVOIR)
COMPRESSOR
HIGH PRESSURE
CUT OUT
ICE CHUTE
EXPANSION VALVE
CLEANING DRAIN
TUBE
November, 1988
Page 16
COMPONENT DESCRIPTION: Control Box
TRANSFORMER
NM1250R
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.
Transformer: Supplies low voltage to the
circuit board.
POTENTIAL
RELAY
Pump Down Control: A switch to control the
compressor, depending upon low side
pressure: closes at 18 PSIG, and opens at 8
PSIG.
Potential Relay: The compressor start relay.
On/Off Switch: Manual control for the
machine.
Reset Switch: Manual reset. Glows when the
unit shuts off from ice discharge chute being
overfilled (opening the microswitch at the top
of the chute), or if either of the pressure cut
out switches opens.
PUMP DOWN
CONTROL
SWITCH
OF/OFF
SWITCH
CIRCUIT
BOARD
CONTACTOR
RESET SWITCH
November, 1988
Page 17
NM1250R
ELECTRICAL SEQUENCE
Refer the wiring diagram as needed.
If the machine is switched off at the master
switch, but is otherwise ready to go, switching
the master switch to ON does the following:
••The bin empty light on the circuit board
goes on
••
There is a 15 second delay
••If there is enough water in the reservoir, the
circuit board will allow the machine to start
up.
Start up consists of:
••The liquid line relay and auger motor relay
become energized, connecting power to the
liquid line solenoid coil and the windings of
the auger motor.
••The liquid line solenoid opens, raising the
low side pressure.
••The pump down control closes
••The auger motor starts, and the centrifugal
switch closes, connecting power to the
compressor contactor coil.
••The contactor is energized, connecting
power to the compressor, and the
compressor starts.
••As ice goes past the ice level sensors, the
bin empty light will be 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
machine shuts down.
Shut Down consists of:
••
The liquid line solenoid relay opens,
lowering the suction pressure.
••The pump down pressure control opens.
••The compressor contactor opens
••The compressor stops
••The auger motor is run by the circuit board
for 2.5 more minutes, clearing out ice in the
evaporator, and then
••
The auger motor relay opens, and the
auger motor stops.
If the ice level sensor is clear (bin empty) for
more than 15 seconds, the machine will start
up again.
Another purpose of the circuit board is to turn
the machine off if there is not enough water in
the machine.
••When the water level in the reservoir falls
below the water level sensor, the machine
will "shut down"
••When the water refills the reservoir, the
machine will start up again.
Separate from the circuit board:
••If the high pressure control (cut out) opens,
the machine will stop immediately (through
the relays on the circuit board) and cause
the reset switch on the circuit board to light
up. It must be manually reset at the control
and at the reset switch on the circuit board.
••The pump down control switch will stop &
start the compressor.
••If the spout switch opens the machine will
stop immediately (through the relays on the
circuit board) and cause the reset switch on
the circuit board to light up. It is a manual
reset at the circuit board.
The master switch is the manual control for
the complete machine, but it is not a service
disconnect.
November, 1988
Page 18
OPERATION
WATER LEVEL
NM1250R
Water
Water enters the machine through the 3/8"
male flare at the rear of the cabinet, goes to
the water reservoir which it enters through the
float valve.
The water then goes out the bottom of the
reservoir tank to the bottom of the evaporator.
Reservoir overflow or evaporator
condensation is routed to the drain.
ADJUSTMENT OF THE
WATER LEVEL
RESERVOIR
STRAINER
WATER
INLET
EVAPORATOR
DRAIN
DRAIN
November, 1988
Page 19
NM1250R
OPERATION:
Beginning at the compressor, the refrigerant
502 is compressed into a high temperature
gas. The discharge line directs this gas to the
condenser and to the head pressure control
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 liquid line connection at the
head pressure control. If the head pressure
is high enought the liquid refrigerant will go
through the valve and enter the receiver.
From the receiver, the liquid refrigerant flows
through the liquid line valve and then to the
expansion valve.
The thermostatic expansion valve meters
liquid refrigerant into the evaporator, the
volume of liquid refrigerant depending upon
the temperature of the evaporator; warmer
evaporators get more refrigerant and colder
evaporators get less. At the evaporator, the
refrigerant enters an area of relatively low
pressure, where it can easily "boil off" or
evaporate. As it evaporates, it absorbs heat
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
THERMOSTATIC
EXPANSION
VALVE
EVAPORATOR
RECEIVER
HIGH PRESSURE
CONTROL SWITCH
COMPRESSOR
November, 1988
Page 20
OPERATION: Refrigeration
THERMOSTATIC
EXPANSION
VALVE
LOW CONDENSING TEMPERATURE
NM1250R
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 ththe condenser and the
receiver. This forces more refrigerant into the
DISCHARGE
LINE
LIQUID LINE
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.
REMOTE CONDENSER
DETAIL OF HEAD
PRESSURE CONTROL
VALVE
HEAD
PRESSURE
CONTROL
VALVE
RECEIVER
LIQUID LINE
VALVE
EVAPORATOR
COMPRESSOR
HIGH PRESSURE
CONTROL SWITCH
November, 1988
Page 21
NM1250R
OPERATION: Refrigeration
DISCHARGE
LINE
REMOTE CONDENSER
LIQUID LINE
LIQUID LINE VALVE
(CLOSED)
RECEIVER
PUMP DOWN
During the pump down cycle (usually initiated
by the circuit board de-energizing the liquid
line valve) the discharge gases flow through
their normal path to the remote condenser,
through the head pressure control, and into
the receiver. At this point the refrigerant flow
November, 1988
COMPRESSOR
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 pump down
control, opens turning the compressor off.
Page 22
NM1250R
MAINTENANCE AND CLEANING
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
A Scotsman Ice System represents a sizable investment of time and money in any company’s
business. In order to receive the best return for that investment, it MUST receive periodic
maintenance.
It is the USER’S RESPONSIBILITY to see that the unit is properly maintained. It is always
preferable, and less costly in the long run, to avoid possible down time by keeping it clean;
adjusting it as needed; and by replacing worn parts before they can cause failure. The following
is a list of recommmended 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/////////////////////////////
Electricial power will be ON when doing in
place cleaning. Switch it OFF before
completing the cleaning process.
/////////////////////////////////////////////////////////////////////
ICEMAKING SYSTEM: In place cleaning
1. Check and clean any water treatment
devices, if any are installed.
2. Pull out and remove 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 postion and replace the end
cap.
///////////////////WARNING//////////////////////////////////
Scotsman Ice Machine Cleaner contains
Phosphoric and Hydroxyacetic acids.
These compounds are corrosive and may
cause burns. If swallowed, DO NOT induce
vomiting. Give large amounts of water or
milk. Call Physician immediately. In case
of external contact, flush with water. KEEP
OUT OF THE REACH OF CHILDREN.
///////////////////////////////////////////////////////////////////
7. Prepare the cleaning solution: Mix eight
ounces of Scotsman Ice Machine Cleaner with
three quarts of hot water. The solution should
be between 90 and 115 degrees F.
8. Slowly pour the cleaning solution into the
water reservior 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 reservior is
nearly empty, switch the master switch to OFF.
11. After draining the reservior, as in step 6,
wash and rinse the water reservoir.
12. Remove the block from the float in the
water reservoir.
13. Switch the master switch to ON
14. Continue ice making for at least 15
minutes, to flush out any cleaning solution.
Check ice for acid taste - continue icemaking
until ice tastes sweet.
///////////////////////////WARNING/////////////////////////
DO NOT USE any ice produced from the
cleaning solution.
Be sure no ice remains in the bin.
/////////////////////////////////////////////////////////////////////
15. Remove all ice from the storage bin.
16. Add warm water to the ice storage bin and
throughly 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.
November, 1988
Page 23
SLIDE IN AND
OUT
ICE
SWEEP
NM1250R
ICEMAKER MAINTENANCE:
////////////////////////////WARNING/////////////////////////////
Disconnect electrical power before begining.
//////////////////////////////////////////////////////////////////////////
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.
WATER
RESERVOIR
WATER
LEVEL
SENSOR
ICE DISCHARGE
CHUTE
ICE LEVEL
SENSORS
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: SENSOR TIP
IS MADE OF GLASS
///////////////////////////////////////////
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 buildup.
3. The top bearing in the breaker should also
be checked at least two times per year.
Check the thrust bearing by:
••removing the ice chute cover
••unscrewing the ice sweep
••removing the water shed
••using a spanner wrench and unscrewing
the breaker cover
••unscrewing the auger stud
SPANNER
WRENCH
BREAKER
COVER
BREAKER
November, 1988
Page 24
MAINTENANCE: Auger
NM1250R
////////////////////////////WARNING/////////////////////////////
Disconnect electrical power before begining.
//////////////////////////////////////////////////////////////////////////
In some areas the water supply to the
icemaker will have a great deal of minerals in
it, and that will result in an evaporator and
auger becoming coated with these minerals,
requiring a more frequent removal than twice
per year. If in doubt about the condition of the
evaporator and auger, the auger can be
removed so the parts can be inspected.
Note. Water filters can filter out suspended
solids, but not dissolved solids. "Soft" water
may not be the complete answer. Check with
a water treatment specialist regarding water
treatment.
ALLEN
SCREWS
For more information on removal of these
parts, see REMOVAL AND REPLACEMENT.
1. To remove the auger, remove front and top
panels. If top panel cannot be removed, or if
there is less than 6" clearance over the top of
the machine, the gearmotor/evaporator may
be slid out for service access. See Removal
and Replacement.
2. Remove 3 hex studs holding the ice chute
cover to the ice chutebody, and remove the
cover.
3. Unscrew and remove ice sweep.
4. Loosen band clamp under ice chute, and
remove ice chute body from evaporator.
5. Remove 4 allen screws holding breaker to
evaporator.
6. Pull up on breaker to remove auger.
Allow the auger to dry, the stainless steel of
the auger and evaporator must be clean and
bright.
Clean the auger and evaporator as required.
DO NOT HONE THE EVAPORATOR.
7. Replace the water seal.
8. Reverse to reassemble.
BREAKER &
BEARING &
AUGER
ASSEMBLY
November, 1988
///////////////////////////WARNING//////////////////////////////
The auger has sharp edges, handle with
gloves.
//////////////////////////////////////////////////////////////////////////
Page 25
NM1250R
SERVICE DIAGNOSIS: Condition - No Ice Being Produced
STATUS:
A. Check: Voltage to the unit, restore it if there is none. Compare to the nameplate.
B. Check: The master switch, switch ON if off.
C. Check: The 2 reset switches (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.
1. This pressure switch opens at 450 psig. Check the high side pressure, reset the switch and
observe that the fan is forcing air through the condenser. If the switch opens at pressures below
450 psig, replace the switch. If the pressures rise above the trip out point, and the unit shuts down:
NOTHING OPERATES
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. After the ice melts, the switch will reset but the machine will not restart until
the reset switch in the control box is pressed. 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.
November, 1988
Page 26
NM1250R
SERVICE DIAGNOSIS: Condition - No Ice Being Produced
STATUS:
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.
voltage and the load side does not, replace the transformer.
2. If the transformer is good, and the bin empty light is OFF, check the ice level sensors.
them, clean if needed.
Testor Model NM1 into the circiut board (see page 38).
3. If the transformer is fine, and the "no water" light is ON, check the water level sensor.
NOTHING OPERATES
a. Transformer "load" side should have 12 to 15 volts. If not, check the "line" side.
The line side should have between 208-230 volts. If the line side has the correct
a. Remove sensors by sliding them sideways out of the ice chute. Visually inspect
b. Look through the ice chute "eye" hole for something blocking the ice chute.
c. If the unit still does not run, replace the ice level sensors.
d. If the bin empty light is still OFF, check the circuit board.
1. Unplug "opto trans" and "LED" connectors from the circuit board.
2. Plug "opto trans" and "LED" connectors from the Scotsman Electronic Control
a. Move the "bin full" switch on the tester to the full position. The bin full
light on the tester should be ON, if not, replace the circuit board.
If the bin full light on the tester is ON, move the tester switch to "bin empty"
the light on the tester should go OFF and the bin empty light on the circuit
board should go ON. If not, replace the circuit board. If it does as above,
and the machine still does not run, replace the ice level sensors.
a. Check the water level in the reservoir, restore if low. If the water level is ok:
b. Remove the water level sensor from the reservoir and clean the tip if dirty.
////////////////////////////////////////////////////////////////////
CAUTION: THE TIP IS MADE OF GLASS
///////////////////////////////////////////////////////////////////
c. Replace the water level sensor. If the no water light is still on, check that the
"water sen" plug is firmly plugged into the circuit board.
d. If the no water light is still on,
1. Unplug the "water sen" connector from the circuit board.
2. Plug "water sen" connector from the 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
November, 1988
Page 27
NM1250R
SERVICE DIAGNOSIS: Condition - No Ice Being Produced
STATUS:
A. Check the pump down control switch.
1. This pressure switch opens at 6-10 psig, and closes at 16-20 psig. If open check the low side
pressure, if after running the machine the switch opens at a pressure higher than 10 psig, replace
the switch.
The low pressure control switch could remain open for any of the following reasons: Low
refrigerant charge, auger not turning, restricted system, TXV not opening, liquid line valve not
opening.
2. Check the low side pressure, the low pressure cut out switch should remain closed at any
pressure higher than 10 psig. If less than that:
replace it. Replace the drier, evacuate, and weigh in the nameplate charge.
GEARMOTOR OPERATES, COMPRESSOR DOES NOT
a. Check if the auger is turning, if it is not, remove the gearbox and:
Check for internal damage, repair and replace in the machine.
b. Check for low charge, add some refrigerant, if the unit begins to operate, (normal low
side pressure being about 30 psig) stop and look for a leak, repair, replace the drier,
evacuate, and weigh in the nameplate charge. If, with added charge,
the unit does not operate:
Check for a restricted system, replace the drier, evacuate, and weigh in a
nameplate charge.
Check for a Thermostatic Expansion Valve that does not open, if defective,
c. Check the liquid line solinoid 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, replacethe circuit board.
If there is power to the valve, the coil may be open, or the valve jammed, replace
the valve.
November, 1988
Page 28
NM1250R
SERVICE DIAGNOSIS: Condition - No Ice Being Produced
STATUS:
B. Check the compressor relay.
The relay is on the circuit board, if it does not supply power to the liquid line valve coil, the low
pressure control will not close, and the compressor will not run.
1. Check for power at the liquid line valve coil, if none:
at the relay, but none at the coil,
2. Check the coil. If the coil is open, replace the liquid line valve.
3. Check the auger drive motor centrifugal switch. If, when the drive motor is running, contact
4 (black wire removed) has no power, and all of the above switches have been checked, replace
the centrifugal switch, or the drive motor.
4. If the compressor relay on the circuit board has power on the NO contact, but not on the COM
contact, replace the circuit board.
C. Check the compressor contactor.
1. If the liquid line valve is open, and the gearmotor is running, the low pressure control shoud be
closed, and the compressor contactor should be energized. If not:
GEARMOTOR OPERATES, COMPRESSOR DOES NOT
a. Check for power at the compressor relay at the circuit board. If there is power
Check for an open wire between the relay and the coil.
a. Check for power at the gearmotor terminal to the contactor, if none:
Replace the drive motor or the centrifugal switch in the drive motor.
b. Check for power at the high pressure control, if none, check that control.
c. Check the coil of the contactor, if open, replace the contactor.
D. Check the compressor
1. Check for power at the compressor: check the start relay, and start capacitor.
2. Check the windings of the compressor for open windings or shorts to ground.
Replace those items found defective.
November, 1988
Page 29
NM1250R
SERVICE DIAGNOSIS: Condition - Low Ice Production
I. STATUS:
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
B. Check the evaporator
1. Clean the evaporator, the mineral build up will adversely affect the ice machines production.
2. Check the evaporator for water leaks, replace the water seal if found to be leaking.
3. Check the low side pressure; normal is about 30 psig. If low, assume a refrigerant leak, locate,
repair and recharge.
4. Check the insulation on the evaporator. It should be dry, with no wet spots or frost. If the
insulation has failed: replace the evaporator or add extra insulation in the form of foam tape
to the evaporator.
EVERYTHING IS OPERATING
the discharge and liquid lines are insulated, and do not touch each other
where not insulated.
If no leak, the TXV may be restricted, defective or not adjusted properly. If needed,
replace the TXV, evacuate, and recharge per nameplate.
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 definate bearing on this. A unit with a marginal charge in summer, will be undercharged
when the outside air temperature drops. The only correct way to charge this unit is to weigh in the
nameplate charge.
November, 1988
Page 30
REMOVAL AND REPLACEMENT
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.
NM1250R
FLOAT
ICE DISCHARGE CHUTE
SLIDE THE
SENSOR
HODERS LEFT
TO REMOVE
FROM THEICE
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 cube chute.
November, 1988
Page 31
BEARING
NM1250R
REMOVAL AND REPLACEMENT: Bearing And Breaker
Note: Removal of the auger, water seal,
evaporator and gearmotor must begin at the
top of the assembly.
To Remove the Breaker Bearing Assembly:
//////////////////////////////WARNING////////////////////////////
Disconnect the electrical power to the
machine at the building source BEFORE
proceeding with any repair.
//////////////////////////////////////////////////////////////////////////
1. Remove panels and disconnect electrical
power.
2. Unscrew three studs and remove ice chute
cover.
3. Unscrew and remove ice sweep.
4. Remove insulation halves from outside of
ice chute, loosen band clamp under ice chute,
lift up and remove ice chute.
5. The breaker may be removed from the
auger and evaporator without disturbing the
auger.
a. Use spanner wrench and unscrew breaker
cover from breaker (left hand threads)
b. Unscrew auger stud from top of auger.
c. Unscrew 4 allen head cap screws holding
breaker to evaporator.
d. Lift up, and remove breaker/bearing
assembly from auger & evaporator.
6. Service the bearing. Check for rust, rough
spots and damage.
a. The bearing is pressed into the breaker, to
remove the bearing and replace it an arbor
press is needed.
b. Replace lower seals before installing new
bearing in breaker.
Note: seals must be pressed in with a tool
pushing against the outer edge only, they will
not install by hand.
Replace parts as required. Re-grease bearing
with Scotsman part no. 19-0609-01 bearing
grease. Replace top seal, and check the
o-rings, replace if cut or torn.
7. Reverse to reassemble: specific tools and
materials are required to install properly.
a. Add food grade grease such as Scotsman
part number 19-0569-01 to the seal area
before installing on the auger.
b. Check the seal to shaft areas for cuts, or
rough spots: none are permitted.
SPANNER
WRENCH
Step 5-a Step 5-b Step 5-c & Step 6
ICE SWEEP
BREAKER
AUGER
STUD
BREAKER
COVER
SEALS
November, 1988
Page 32
REMOVAL AND REPLACEMENT: Auger
NM1250R
To Remove the Auger:
Turn off the water to the machine, and unclip
the evaporator drain hose, pull it down and
drain the evaporator into the bin or a container.
1. The top panel must be removed, or, if that
is not possible, the gearmotor and freezer
assembly must be pulled part of the way out
from the cabinet. To do that:
a. Unclip the electrical wires from the hanger
near the drive motor.
b. Remove the bolt holding the gearmotor
plate.
c. Pull the assembly out.
2. The auger and breaker/bearing may now be
removed as an assembly.
a. Unscrew 4 allen head cap screws holding
breaker to evaporator.
b. Lift up on breaker and remove auger from
evaporator.
BREAKER
ASSEMBLY
ALLEN
SCREWS
c. Unscrew 4 allen head cap screws holding
breaker to evaporator.
d. Use a slide hammer type puller to pull on
the auger at the threaded hole. The size of
that hole is 5/8"-18.
Inspect the auger, the critical areas of the
auger are:
a. The auger body. It should be clean and
shining. Sometimes an auger will appear
clean when wet, but after it is dry it will be
seen to be stained. Scrub the auger with ice
machine cleaner and hot water.
///////////////////////////WARNING//////////////////////////////
Ice machine cleaner is an acid. Handle it with
extreme care, keep out of the reach of
children.
//////////////////////////////////////////////////////////////////////////
SLIDE
HAMMER
PULLER
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. Use spanner wrench and unscrew
stainless breaker cover from breaker (left
hand threads)
b. Unscrew auger stud from top of auger.
November, 1988
GEARMOTOR
PLATE SLID OUT
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.
Page 33
NM1250R
REMOVAL AND REPLACEMENT: Evaporator & Water Seal
To Remove the Water Seal:
(Assuming all steps to remove the auger have
been performed.)
1. The gearmotor/evaporator assembly will
have to be pulled away from the machine (if
not yet done).
2. Remove the 4 hex head cap screws holding
the evaporator to the gearmotor assembly.
Lift the evaporator up and off of the gearmotor.
3. Remove the snap ring or wire retainer from
the grove under the water seal.
4. Pull or drive out the lower half of the water
seal.
To Replace the Water Seal:
1. Lubricate the water seal with water, and
push the water seal into the bottom of the
evaporator slightly past the grove for the snap
ring.
2. Replace the snap ring and pull the water
seal down against it.
3. The part of the water seal that rotates with
the auger must also be replaced. Remove the
old part from the auger and clean the
mounting area.
4. Place a small bead of food grade silastic
sealant (such as 732 RTV or Scotsman part
number 19-0529-01) on the area of the auger
where the water seal is to be mounted.
5. Carefully push the water seal (rubber side
against the auger shoulder and the silastic.)
/////////////////////////////CAUTION///////////////////////////
Do not get any silastic onto the face of the
seal.
/////////////////////////////////////////////////////////////////////////
6. Allow the auger and seal to air dry until the
silastic is dry on the surface.
7. If the original water seal was leaking, it
would be a good idea to inspect the interior of
the gearmotor.
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.
//////////////////////////////////////////////////////////////////////////
b) At the suction line at the joint about 3" from
the evaporator.
3. Remove the evaporator.
4. Unsweat the drier from the liquid line.
5. After installing a new water seal in the new
evaporator ( see "To Replace the Water Seal")
resweat the tubing connections.
6. Install an new drier in the liquid line.
7. Evacuate the system until dehydrated, then
weigh in the nameplate charge. Check for
leaks.
8. Install auger, breaker, breaker bearing
assembly, and ice discharge chute in reverse
order of disassembly. See "To Reassemble
Evaporator and Auger"
WATER SEAL
RETAINING RING
November, 1988
Page 34
REMOVAL AND REPLACEMENT: Evaporator
PLACE FOOD
GRADE SILASTIC
HERE
CHARGING
CYLINDER
NM1250R
To Reassemble the Evaporator and Auger
1. After the gearmotor has been inspected,
fasten the evaporator to the gear motor, be
sure that the number of shims indicated on the
gear case cover is in place between the
gearcase cover and the drip pan gasket.
Torque the bolts to 110 inch pounds.
2. Lower the auger into the evaporator barrel,
slightly turning it to match up with the drive
end. Do Not Drop Into the Evaporator.
3. Complete the reassembly by reversing the
disassembly for the breaker & thrust bearing
assembly.
Head Pressure Control Valve
1. 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 that the number on
the side of the valve is "220".
REPLACING THE WATER SEAL
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.
CHARGING PROCEDURES
Extra care must be taken when recharging this
remote system. No liquid refrigerant maybe
placed in the system at the compressor. DO
RECEIVER
KING VALVE
8. Evacuate the system, and weigh the
nameplate charge into the receiver.
NOT use the schrader valves at the front of
the unit for weighing in the charge. All liquid
refrigerant must be weighed into the receiver
through the "front seated" king valve.
SERVICE PORT
November, 1988
Page 35
NM1250R
REMOVAL AND REPLACEMENT: Gearmotor
To Remove and Repair the Gearmotor
Assembly:
(Assuming that the procedures through
removal of the water seal have been
performed.)
1. Remove the electrical wires from the gear
drive motor.
2. Unscrew the 4 cap screws holding the
gearmotor to the gearmotor plate.
3. Remove the gearmotor from the icemaker.
To Inspect the gearmotor.
A) Remove the cap screws holding the
gearmotor case halves together and pry the
two cases apart.
B) To lift off the cover, lift up until you can feel
internal contact, then pull the cover towards
the output gear end, and then lift the cover
(with drive motor attached) up and away from
the gear motor case.
Note: The case cover output gear, bearings,
and shaft are one pressed together assembly.
Replace as a unit.
C) Inspect the oil, gears, and bearings. If the
oil level and condition is acceptable, quickly
check the gears and bearings. They are likely
to be fine if the oil is.
If there is evidence of water in the oil (rusty
bearings and gears; the oil having a creamy
white appearance; oil level too high) carefully
inspect the bearings and gears. If in doubt
about the condition of a part, replace it. The oil
quantity is 14 fluid ounces, do not overfill.
Note: The gears and bearings are available
only as pressed together sets.
D) After replacing parts as required, (if any)
reassemble the gearcase. The two smaller
gears and the oil should be in the lower case,
the output gear will be with the cover. As you
lower the cover onto the lower case, cover will
have to be moved closer to the second gear
after the output gear has cleared the second
gear top bearing.
E) After the case is together, and the locating
pins are secure in both ends, replace all cap
screws.
Note: If the gearcase cover was replaced, the
replacement part was shipped with a certain
number of shims. The number of shims used
must match the number on the gearcase
cover. Do not use the old shims unless there
is a shortage.
4. Bench test the gearmotor, check for oil
leaks, noise, and amp draw.
November, 1988
Page 36
DRIVE MOTOR
REMOVAL AND REPLACEMENT: Gearmotor
WATER SHED
NM1250R
OUTPUT
SHAFT SEAL
GEARCASE COVER,
OUTPUT SHAFT,
OUTPUT GEAR, AND
BEARINGS
CENTRIFUGAL
SWITCH
SHIMS
MOTOR BEARING
SHAFT SEAL
1ST GEAR AND
BEARINGS
2ND GEAR AND
BEARINGS
GASKET
GEARCASE
November, 1988
Page 37
NM1250R
ELECTRONIC CONTROL TESTER
INSTRUCTIONS FOR USING TESTER MODEL FC1
(Optional, order part no. A33942-001)
(These instructions assume that the unit will not run, and prior investigation of electric power,
controls, and mechanical parts indicates that the electronic circuit may be at fault.)
/////////////////////////////////////////////////////////////////////////////WARNING/////////////////////////////////////////////////////////////
These procedures require the machine to be connected to the power supply. The voltages of the
electronic circuit are very low, but HIGHER VOLTAGES ARE PRESENT IN THE UNIT. Do not
touch anything but the tester while the unit is being checked out. Make all connections to the
circuit board with the ELECTRICAL POWER OFF.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
Bin Control
Note: All testing is done with the
electrical power on, the master switch on, and
all reset switches "reset" .
1. Unplug "photo trans" and "LED" connectors
from the circuit board.
2. Plug "photo trans" and "LED" connectors
from the tester into the circuit board.
a. Move the "bin full" switch on the tester to
Full. The light on the tester should be ON.
If the light on the tester is not on, the circuit
board should be replaced.
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 machine still does not run, replace the
ice level sensors.
LIGHT GOES ON
SWITCH TO
"FULL"
PHOTO TRANS
LED
LIGHT
GOES ON
LIGHT
GOES OFF
SWITCH TO
"BIN EMPTY"
November, 1988
Page 38
ELECTRONIC CONTROL TESTER
NM1250R
Water Level
1. Unplug "water sen" connector from control
board.
2. Plug "water sen" connector from Scotsman
tester into circuit board.
a. Move "water" switch on tester to No Water
position. The No Water light on the circuit
board should go ON. If not, replace the circuit
board.
LIGHT ON
WATER SENS
b. Move the "water" switch on the tester to the
Water position. The No Water light on the
board should go OFF. If not replace the circuit
board. If the light does go off, replace the
water level sensor.
LIGHT OFF
SWITCH TO
"NO WATER"
SWITCH TO
"WATER"
November, 1988
Page 39
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