Scotsman UF424A-1A User manual

Technical Manual for
Model UF424 and UN324

UF424 / UN324 Technical Manual
September 2017
Page 2
To the owner or user: the service manual is intended
to provide you and the maintenance or service
technician with the information needed to install,
startup, clean, maintain and repair this product.
Observe any caution or warning notices. They are
important and provide notice of potential hazards.
Keep this manual for future reference.
If additional technical information is needed, go to
Scotsman’s website, www.scotsman-ice.com.
Note: This is a commercial product. If service is
needed on a unit in a residence, warranty may be
limited. Use a commercial service company. Locate
one from the Scotsman website: www.Scotsman-ice.
com
Table of Contents
Specications .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 3
Cabinet Drawing. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 4
Plan and Front Views .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 5
Side and Back Views.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 6
Operational Data .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 7
Placement.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 8
Installation . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 9
Initial Start up .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 10
Maintenance and Cleaning .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 11
Condensers and Air Filter Cleaning.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 13
Operation .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 14
Basic Troubleshooting . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 15
Controller Functions . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 16
Controller Details .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 17
Controller Diagnostics . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 18
Electrical Sequence.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 19
Testing Compressor.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 20
Replace Compressor .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 21
Replace Fan Motor .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 22
Testing Sensors.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 23
Panel Removal .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 24
Remove Ice Storage Bin. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 25
Remove Gear Reducer .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 26
Remove Auger. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 27
Replace Evaporator.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 28
Replace Auger Motor .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 29
Prep to Replace Water Seal or Bearings .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 30
Replace Water Seal and Auger Bearings .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 31
Replace Electrical Components . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 32
Schematic Diagram .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 33
Wiring Diagram .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 34
Introduction

UF424 / UN324 Technical Manual
September 2017
Page 3
Specications
This ice maker is designed to be installed indoors,
in a controlled environment. Although it can operate
in a wide range of air and water temperatures, it
will provide the best performance if not subject to
extremes.
Air Temperature Limitations
• Maximum: 100o F or 38oC
• Minimum: 50oF or 10oC
Water Temperature Limitations
• Maximum: 100oF or 38oC
• Minimum: 40oF or 4.4oC
Water Pressure, Potable
• Maximum: 80 PSI or 5.5 BAR
• Minimum: 20 PSI or 1.3 BAR
Water Pressure, Condenser inlet
• Maximum: 145 PSI or 10 BAR
• Minimum: 20 PSI or 1.3 BAR; can be as low as
5 PSI or 0.3 BAR if clean and supplied with 45oF
water.
Condenser GPM
• 70oF or 21oC water: 0.25 GPM or 0.95 LPM
• 50oF or 10oC water: 0.15 GPM or 0.57 LPM
Voltage 115 volt models
• Maximum 126 VAC
• Minimum 104 VAC
Water Conductivity:
• Minimum:10 micro Siemens/CM
RO water may be supplied to the potable water
system, but if it has less than the above conductivity,
the water level sensor will not detect water and the
unit will not make ice.
Deionized water is not recommended due to its
potential corrosive nature and any damage caused by
DI water will not be covered by warranty.
Operating the machine outside of any of the above
limitations is considered abuse and any resulting
damage is not covered by warranty and could cause a
complete loss of warranty coverage.
Warranty Information
The warranty statement for this product is provided
separately from this manual. Refer to it for applicable
coverage. In general warranty covers defects
in material or workmanship. It does not cover
maintenance, corrections to installations, or situations
when the machine is operated in circumstances that
exceed the limitations printed above.
Product Information:
The UF424 produces aked ice and the UN324
produces nugget ice. The ice is stored in an insulated
bin with ice level automatically maintained by the
control system.
A back ow preventer may be required by local
plumbing codes.
Has a 5.5 ft. power cord with NEMA 5-15P plug.
Air cooled models ows in the right front and out the
left front and include a cleanable air lter.
Legs are provided, thread size is 5/8-11. Replacement
leg kit number is KLP7.
Machine may be installed without legs.
For available options and kits, see sales literature.
Scotsman Ice Systems are designed and
manufactured with the highest regard for safety and
performance. They meet or exceed UL563, veried by
Intertek, ETL.

UF424 / UN324 Technical Manual
September 2017
Page 4
Cabinet Drawing
DRAIN
POWER
CORD
WATER INLET
ACCESS

UF424 / UN324 Technical Manual
September 2017
Page 5
61cm
24.0in
72.3cm
28.4in
99cm
39.0in
84.7cm
33.4in
50.8cm
20.0in
AIR
EXHAUST
AIR
INLET
Plan and Front Views

UF424 / UN324 Technical Manual
September 2017
Page 6
15.1cm
6.0in
51.4cm
20.3in
5.3cm
2.08in
UTILITY
CLEARANCE
72.8cm
28.7in
16.8cm
6.6in
7.8cm
3.1in
17.5cm
6.9in
24.5cm
9.7in
13.6cm
5.4in
11.9cm
4.7in
WATER INLET
3/8 FLARE
UNIT DRAIN
3/4" FPT
POWER
CORD
CONDENSER WATER
INLET 3/8-18NPT
CONDENSOR
WATER DRAIN
CONNECTION
1/2-14 NPT
WATER REGULATOR
ADJUSTMENT ACCESS
Side and Back Views

UF424 / UN324 Technical Manual
September 2017
Page 7
Model
Electrical
(Volts/Hz/Phase)
Condenser
High Pressure
Switch (PSIG) Refrigerant
Charge
(R-134a)
Ounces
Maximum Fuse Size
or Breaker (Amps)
Cut Out Cut In
UF424A-1A / UN324A-1A 115/60/1 Air 260 190 12 15
UF424W-1A / UN324W-1A 115/60/1 Water 260 190 12 15
UF424A-6A / UN324A-6A 230/50/1 Air 260 190
Model Typical Watts Typical Amps Auger Motor Amps Compressor Amps
UF424A-1A / UN324A-1A 560 - 690 6.3 - 7 1.1 - 1.4 5 - 5.8
UF424W-1A / UN324W-1A 540 - 575 6.1 - 6.7 1.1 - 1.4 5 - 5.8
UF424A-6A / UN324A-6A
Model Condenser 70/50 Suction
Pressure
(PSIG)
90/70 Suction
Pressure
(PSIG)
70/50
Discharge
Pressure
(PSIG)
90/70
Discharge
Pressure
(PSIG)
UF424A-1A / UN324A-1A Air 6 - 8 8 - 9 130-135 180 - 185
UF424W-1A / UN324W-1A Water 6 - 8 6 - 8 135 135
Note: 70/50 and 90/70 refer to the air and water temperatures (in degrees F) the machine was tested in. All
eld conditions are unique, but at temperatures near those listed a eld machine will have similar results.
Operational Data

UF424 / UN324 Technical Manual
September 2017
Page 8
Placement
The location of the equipment should be selected
with care. Consideration should be given to allow
adequate space for air cooled models to breathe.
The ice machine is not designed for outdoor
use. It must be installed indoors, in a controlled
environment. The air and water temperatures must
not exceed rated limits.
Scotsman assumes no liability or responsibility of
any kind from products manufactured by Scotsman
that have been altered in any way, including the use
of any part and/or other components not specically
approved by Scotsman.
Scotsman reserves the right to make design changes
and/or improvements at any time.
Specications and design are subject to change
without notice.
Airow on air cooled models:
Intake from the right grill
Exhaust from the left grill
Do not install where this air ow is blocked.
The power outlet should be located within the length
of the supplied power cord. If legs will be used, allow
space for the total cabinet height.
Air cooled models in a small room will require
ventilation to exhaust heat from the condenser. The
condenser fan and motor will generate some noise
while the machine is running. Noise sensitive areas
should consider water cooled equipment or locate
the machine where the noise from ice making will not
objectionable.
Unpack
1. Separate the carton from the shipping pallet
2. Inspect for any hidden shipping damage. If any
is found, retain carton and notify carrier for potential
claim. Shipping damage is not covered by warranty.
Caution: Tip Over hazard to prevent injury or
damage to the machine please use caution when
lifting the unit. It will easily tips to the rear.
3. Remove bolts holding machine to pallet.
4. Install the legs. The legs are to be screwed into the
same holes the shipping bolts were removed.
5. Remove the protective plastic covering the panels.
The longer it is left on the panel, the more di󰀩cult it
will be to remove it.
Spacing:
No additional spacing is required at the top or sides.
However, suggested minimum side clearance for the
installation is 1/8’’ or 3.2 mm and suggested minimum
top clearance is 1/4” or 6.4 mm.
The machine may be installed with 0 clearance at the
back. Do not block louvers at the front of the cabinet.
Pre Installation:
Water supplied to the ice machine should be ltered.
Install a lter system that lters out suspended solids.
It may be necessary to add a coarse pre-lter ahead
of the ne lter.
Inspect the place where the ice machine is to be
installed. Check for:
• Space for the cabinet
• Water Supply
• Drain Availability
• Electrical Power Supply
Airow

UF424 / UN324 Technical Manual
September 2017
Page 9
Installation
Note: The building drain inlet must be lower than
the drain outlets at the back of the ice machine.
The water supply must have a hand shut o󰀨 valve
accessible when the unit is installed.
For the Plumber
1. Connect cold potable water to the 3/8’’ male
are behind the lower back panel. A water
lter is recommended. Flush the water line
prior to connecting to the ice machine.
A loop of copper tubing may be used between the ice
machine and the water supply. This will allow the ice
machine to be pulled out from its installed location
without disconnecting water. No back ow preventer is
required in the potable water line. This is provided by
the reservoir seat, which is above the reservoir water
level and cannot be siphoned
2. Connect a drain tube to the drain tting. Drain
tubes for a water cooled machine should be
run separately. The bin drain tting is 3/4’’
FPT. And it is plastic. Do not overheat.
• Drain tube material must be rigid and meet
local code.
• Traps in the bin drain line without vents
ahead of them will cause poor draining
• The bin drain must be vented if there is a
long horizontal run 5 feet or more. All drains
are gravity and must have a minimum fall of
1/4’’ per foot of horizontal run.
• Maintain the air gap required by local code
between the end of the drain to, and the
building drain receptacle.
• Drain tubing should be insulated to prevent
condensation from forming on the tubing.
3. Water cooled models have a separate 3/8”
FPT tting for condenser water inlet. DO
NOT FILTER water to this connection. The
condenser drain is1/2’’ FPT and does not
need a vent.
For the Electrician
This is a cord-connected unit and must be on a
separate single phase power supply. Check the name
plate for the correct voltage. The maximum fuse size
for this circuit should be 15 A, per the nameplate use
fuses or HACR circuit breaker.
Follow all local codes. This unit must be
grounded. Do not use extension cords and
do not disable or bypass the ground pin on
electrical plug.
After utility connections
1. Level the cabinet, use the leg levelers on
the end of the legs to adjust to cabinet height.
Legs should have been installed when the unit
was unpacked.
2. Wash the bin and hood. If desired, the interior
of the bin could be sanitized.
3. Locate the scoop, wash it and have it
available for use when needed.
Water
Inlet
Drain
Utility Connections

UF424 / UN324 Technical Manual
September 2017
Page 10
Initial Start up
Start up:
1. Remove louvered front panel.
2. Open bin door and remove the inner panel, held in
place by 4 thumb screws.
3. Open the water valve. Observe that water enters
the water reservoir, lls and then shuts o󰀨. Check
for leaks. Repair any leaks before going further.
4. Switch electrical supply on. Lights on controller
will ash and then the power light will remain on.
The code display will show O.
5. Push and release the On/O󰀨 button. The machine
will start the ice making process. The code display
will show F . Air cooled models will discharge
warm air out the left side of the front panel.
Water cooled models will discharge warm (about
1200F/48
0
C) water out of the condenser drain. In
a few minutes, ice will begin to fall into the bin.
6. Push the on/o󰀨 button to switch the machine o󰀨.
Scoop out any ice in the bin.
7. Create a solution of sanitizer. Mix 4oz/118ml of
NuCalgon IMS III and 2.5gal/9.5L of (90
0
F/32
0
C
to 110
0
F/43
0
C) potable water to create a 200 ppm
solution.
8. Sanitize bin by wiping all surface areas with the
sanitizer solution. Allow to air dry.
9. Turn the ice maker on by pressing the on button.
10. Replace inner panel, front cover and louvered
panel.
11. Give the owner/user this manual, instruct him/her
in the operation and maintenance requirements
of the unit. Make sure they know who to call for
service.
Fill out the Customer Evaluation and Warranty
Registration form, and mail it in to Scotsman or
register the unit at Scotsman’s website (www.
scotsman-ice.com).
Once started, the ice machine will automatically
make ice until the bin level sensors are blocked.
This will happen once the ice piles up to the sensors.
The typical ice level when the machine is o󰀨 will be
several inches below the door. When ice level drops
from use or meltage, the ice machine will resume
making ice.
Tip: To maximize ice storage scoop the ice to the
sides of the bin.
Noise:
This is a commercial ice machine. It contains a
powerful compressor, heavy duty gear reducer and,
if air cooled, a fan motor. It will produce some noise
when it is making ice. Every e󰀨ort was made during
its design to minimize the sound level but some is
unavoidable.
Final check list:
Ice machine is installed indoors with air
and water temperature controlled within
the limitations detailed in this manual
Ice machine is level in its nal position
Electrical disconnect (switch or plug as
required) is within sight of the installed
machine
Electrical circuit is dedicated to this ice
maker
Voltage has been conrmed within the
specications in this manual and the name
plate on the ice maker
Plumbing connections are complete and
tested for leaks
Ice maker is installed with proper
clearance, allowing for service and utility
connections
Water shut o󰀨 valve installed near the ice
maker