Scotsman | CU3030 | Service manual | Scotsman CU3030 Service manual

CU1526, CU2026, CU3030
Service Manual
Introduction
The design of this cuber is the result of years of
experience and testing. Standard features include
a removable bin for service and an on-off switch at
the front of the cabinet for easy operational control.
Table of Contents
Installation: Product Specifications . . . . . Page 2
Model Number Description. . . . . . . . . . Page 3
Water . . . . . . . . . . . . . . . . . . . . . Page 4
CU1526 and CU2026 Cabinet Layout . . . . Page 5
CU3030 Cabinet Layout . . . . . . . . . . . Page 6
Bin Removal . . . . . . . . . . . . . . . . . Page 7
Plumbing Requirements . . . . . . . . . . . Page 8
Electrical . . . . . . . . . . . . . . . . . . . Page 9
Adjustments . . . . . . . . . . . . . . . . . Page 10
Use and Operation . . . . . . . . . . . . . . Page 11
Control Switches . . . . . . . . . . . . . . . Page 12
Cuber System Information . . . . . . . . . . Page 13
Controller Information . . . . . . . . . . . . Page 14
Component Indicator Light Table . . . . . . Page 15
How It Works - Air Cooled . . . . . . . . . . Page 16
How It Works - Water Cooled . . . . . . . . Page 17
Electrical Sequence - Air or Water Cooled . Page 18
Electrical Sequence - Air or Water Cooled (continued)
. . . . . . . . . . . . . . . . . . . . . . . . Page 19
Electrical Component Details . . . . . . . . Page 20
Refrigeration & Water Systems . . . . . . . Page 22
Control Button Use (from standby - status light off)
. . . . . . . . . . . . . . . . . . . . . . . . Page 26
Test Mode: . . . . . . . . . . . . . . . . . . Page 27
Service Diagnosis . . . . . . . . . . . . . . Page 28
Service Diagnosis - Low ice making capacity - air cooled
. . . . . . . . . . . . . . . . . . . . . . . . Page 31
Cleaning, Sanitation and Maintenance . . . Page 32
Test Procedures - Sensors . . . . . . . . . Page 34
Sensor Testing . . . . . . . . . . . . . . . . Page 35
Test Procedures - Loads . . . . . . . . . . . Page 36
Test Procedures . . . . . . . . . . . . . . . Page 37
Technical Information . . . . . . . . . . . . Page 40
Performance Data, CU1526 . . . . . . . . . Page 41
Performance Data, CU2026 . . . . . . . . . Page 42
Performance Data, CU3030 . . . . . . . . . Page 43
Wiring Diagram, CU1526 and CU2026 60 Hz Page 44
Wiring Diagram, CU3030 60 Hz . . . . . . . Page 45
Wiring Diagram, CU1526 and CU2026 50 Hz Page 46
Wiring Diagram, CU3030 50 Hz . . . . . . . Page 47
Removal and Replacement . . . . . . . . . Page 48
Refrigeration Removal and Replacement Procedures
. . . . . . . . . . . . . . . . . . . . . . . . Page 54
Control Operation . . . . . . . . . . . . . . Page 23
Control Safeties . . . . . . . . . . . . . . . Page 24
Restarts . . . . . . . . . . . . . . . . . . . Page 25
Note any Caution or Warning symbols when they
appear on the product or in this manual. They
indicate potential hazards.
May 2008
Page 1
CU1526, CU2026, CU3030
Service Manual
Installation: Product Specifications
Environmental Limitations
Location Limitations:
The product is designed to be installed indoors, in
a controlled environment. Air cooled models
discharge very warm air into the room. Water
cooled models discharge warm water into the
building’s drain. Space needs to be provided for
service access.
Space Limitations
Do not block air flow at the front.
Minimum
Maximum
Air
temperature
50oF.
100oF.
Water
temperature
40oF.
100oF.
Water
pressure
20 psi
80 psi
Power supply – acceptable voltage ranges
Airflow is in the front left and out the front right.
CU3030 also takes air in from below the cabinet.
Minimum
Maximum
115 volt model
104 volts
126 volts
230 volt model
198 volts
253 volts
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
Air Flow
The product is a self contained cuber with bin. That
type of machine is designed to be free standing
can be built in under the counter.
May 2008
Page 2
CU1526, CU2026, CU3030
Service Manual
Model Number Description
Example:
•
•
•
•
•
•
CU2026SA-1A
C= cuber
U=under the counter type
20= nominal ice capacity in 10s of pounds
26= nominal width of cabinet
S= Cube size. S=small or half dice cube.
M=medium or full dice cube
• A=Condenser type. A=air cooled. W=water
cooled
• -1=115 60 Hz, -32 = 208-230 volt, 60 Hz, -6
= 230 volt, 50 Hz
• A=Series revision code. A=first series
Scotsman ice systems are designed and
manufactured with the highest regard for safety
and performance.
Scotsman assumes no liability of 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.
Note: In some areas of this manual model numbers
may include only the first six characters of the
model number, meaning that the cube size,
condenser type and voltage differences are not
critical to the information listed there.
Product Description & Electrical Requirements
Dimensions
w" x d" x h"**
26.62 x 27.5 x 33
26.62 x 27.5 x 33
30.62 x 30 x 33
Model
Electrical
volts/Hz/phase
Condenser
Total Load
Amps
CU1526SA-1
115/60/1
Air
7.7
15
CU1526SW-1
115/60/1
Water
7.7
15
CU2026SA-1
115/60/1
Air
7.2
15
CU2026SW-1
115/60/1
Water
7.2
15
CU2026SA-32
208-230/60/1
Air
3.7
15
CU2026SW-32
208-230/60/1
Water
2.96
15
CU3030SA-1
115/60/1
Air
10.4
15
CU3030SW-1
115/60/1
Water
10.4
15
CU3030SA-32
208-230/60/1
Air
5.54
15
CU3030SW-32
208-230/60/1
Water
4.48
15
Maximum
Fuse Size*
Table notes: Height is without legs. Medium cube models have the same electrical characteristics as
Small. Series revision code omitted. * Or HACR type circuit breakers.
** If not using legs, add .25" for screws below base. Legs add 6 to 6.75 inches, but the 1/4 inch for the
screws.
May 2008
Page 3
CU1526, CU2026, CU3030
Service Manual
Water
The quality of the water supplied to the ice machine
will have an impact on the time between cleanings
and ultimately on the life of the product. Water can
contain impurities either in suspension or in
solution. Suspended solids can be filtered out. In
solution or dissolved solids cannot be filtered, they
must be diluted or treated. Water filters are
recommended to remove suspended solids. Some
filters have treatment in them for suspended solids.
Check with a water treatment service for a
recommendation.
RO water. This machine can be supplied with
Reverse Osmosis water, but the water conductivity
must be no less than 10 microSiemens/cm.
Water purge
Cube ice machines use more water than what ends
up in the bin as ice. While most water is used
during ice making, a portion is designed to be
drained out every cycle to reduce the amount of
hard water scale in the machine. That’s known as
water purge, and an effective purge can increase
the time between needed water system cleaning.
In addition, this product has the capability to
automatically vary the amount of water purged
based on the purity of the water supplied to it. The
water purge rate can also be set manually.
Adjustments of purge due to local water conditions
are not covered by warranty.
Potential for Airborne Contamination
Installing an ice machine near a source of yeast or
similar material can result in the need for more
frequent sanitation cleanings due to the tendency
of these materials to contaminate the machine.
Most water filters remove chlorine from the water
supply to the machine which contributes to this
situation. Testing has shown that using a filter that
does not remove chlorine, such as the Scotsman
Aqua Patrol, will greatly improve this situation,
while the ice making process itself will remove the
chlorine from the ice, resulting in no taste or odor
impact. Additionally, devices intended to enhance
ice machine sanitation, such as the Scotsman
Aqua Bullet, can be placed in the machine to keep
it cleaner between manual cleanings.
This manual covers several models. The model
number on the product is located in two places, on
the back dataplate and on the model and serial
number tag, located behind the front panel. See the
illustration for the dataplate and serial tag locations.
May 2008
Page 4
CU1526, CU2026, CU3030
Service Manual
CU1526 and CU2026 Cabinet Layout
POTABLE
WATER INLET
3/8 FLARE
39.5
15.55
COND DRAIN
1/2 NPT
(W/C ONLY)
COND WATER
REGULATOR
3/8 NPT
(W/C ONLY)
76.3
30.04
DRAIN
3/4 FPT
15
5.92
11
4.32
POWER CORD
8.1
3.19
6.6
2.60
12.3
4.85
16.5
6.50
69.9
27.5
12.3
4.86
67.6
26.62
13.9
5.48
99.0
39.0
75.3
29.65
10.2
4.00
MINIMUM
UTILITY
CLEARANCE
15.2
6.00
56.2
22.12
56.5
22.25
May 2008
Page 5
CU1526, CU2026, CU3030
Service Manual
CU3030 Cabinet Layout
POTABLE
WATER INLET
3/8 FLARE
60.5
23.82
COND DRAIN
1/2 NPT
(W/C ONLY)
COND WATER
REGULATOR
3/8 NPT
(W/C ONLY)
74.6
29.36
DRAIN
3/4 FPT
17.7
6.99
11
4.33
8.1
3.19
POWER CORD
7
2.77
11.8
4.65
15.9
6.27
76.2
30.0
11.9
4.69
77.8
30.62
13.5
5.30
99.0
39.0
75.3
29.63
10.2
4.00
MINIMUM
UTILITY
CLEARANCE
15.2
6.00
65.9
25.95
61.6
24.25
May 2008
Page 6
CU1526, CU2026, CU3030
Service Manual
Bin Removal
The ice storage bin is removable to allow access to
the refrigeration system for service.
1. Remove front louvers. Remove left then right.
2. If the machine is in an ice making mode, push
and release the Manual Harvest button to release
any ice that might be on the evaporator.
3. Push and hold the controller's Off button to shut
the machine off.
4. Remove all ice from the bin.
Remove bolt
to release bin
5. Disconnect electrical power.
6. Remove door (open about 1.5" and pull bottom
out).
7. Remove the top panel, there are two fasteners
under the front corners of the top. Back them out
and lift the top up, push back slightly and lift panel
up and off the machine..
9. Remove two bolts from the bottom of the bin,
one on the left and one on the right.
10. Remove bolt from the back wall of the bin.
8. Disconnect the drain tube from the bin drain
fitting.
Disconnect
hose before
moving bin.
Remove
bolt to
release bin
11. Pull the bin forward and off the chassis.
May 2008
Page 7
CU1526, CU2026, CU3030
Service Manual
Plumbing Requirements
All models require connection to cold, potable
water. A hand actuated valve within sight of the
machine is required. Air cooled models have a
single 3/8” FPT inlet water connection. Water
cooled models have the same inlet fitting plus an
additional 3/8” FPT condenser inlet water
connection.
2. Connect drain tubing to drain fittings.
3. Route the drain tubing to building drain. Follow
local codes for air gap.
Water Filters
If connecting to water filtration, filter only the water
to the reservoir, not to the condenser. Install a new
cartridge if the filters were used with a prior
machine.
All models require drain tubing to be attached to
them. Air cooled models have a single ¾” FPT
drain fitting in the back of the cabinet. Water cooled
models have the same fitting plus an additional ½”
FPT drain fitting in the back of the cabinet.
Install new tubing when replacing a prior ice
machine, as the tubing will have been sized for the
old model and might not be correct for this one.
1. Connect water supply to water inlet fittings.
3/8" OD tubing is recommended.
Water Filter (if used)
Note: This NSF listed model has a 1" anti-back flow
air gap between the float valve orifice and the
highest possible reservoir water level, no back flow
device is required for the potable water inlet.
Drain Tubing:
Use rigid drain tubes and route them separately –
if water cooled, do not Tee the condenser drain
into the reservoir or bin drain.
Vent the reservoir drain. A vertical vent at the back
of the drain, extended about 8 - 10" will allow the
gravity drain to empty and also keep any surges
during draining from discharging water out the
vent..
Horizontal runs of drain tubing need a ¼” fall per
foot of run for proper draining.
Follow all applicable codes.
Water Inlet
Potable
Water
Connection
Water Cooled
Supply Location
Shut off valve
Water Cooled
Drain Location
Drain
Tubing
Floor Drain
Bin Drain
Connection
Air Cooled Model Plumbing Connections
Water Cooled Plumbing Connections
May 2008
Page 8
CU1526, CU2026, CU3030
Service Manual
Electrical
The machine is supplied with a power cord.
This is a cord-connected unit, and must be on a
separate power supply. Check the dataplate for the
voltage, ampacity and maximum fuse size and per
the dataplate use fuses or HACR circuit breakers.
Follow All Local Codes - This Unit Must Be
Grounded. Do not use extension cords and do not
disable or by-pass ground prong on electrical plug.
Typical Ice Making Cycle Times (minutes).
Listed times are for clean machines in proper
installations. Cycle length at startup will be longer
until the system stabilizes.
Model
70oF air /
50oF. water
90oF. air /
70oF. water
CU1526A
22-25
36-29
CU1526W
21-24
28-31
CU2026A
15-18
25-28
CU2026W
15-18
20-23
CU3030A
12-15
19-22
CU3030W
10-13
15-18
May 2008
Page 9
CU1526, CU2026, CU3030
Service Manual
Adjustments
Bridge Thickness - For the Service Tech Only
1/8-3/16"
bridge
1. Remove left louver, locate controller on and off
switches.
2. Push and hold Off till the machine stops.
3. Remove curtain.
4. Use a hex wrench and rotate the bridge
thickness adjustment screw in 1/8 turn
increments CW to increase bridge thickness.
Rotate CCW to decrease bridge thickness.
Caution: Do not make the bridge too thin or the
machine will not harvest properly. Bridge thickness
adjustments are not covered by warranty.
Too Big
Just Right
Too Small
Ice Bridge Thickness Measurement
Adjustment
Screw
5. Return curtain and louver to their normal
positions.
6. Push and release the On button. Check next
harvest of ice. Repeat steps 1-6 if needed.
Water Purge Setting
The water purge is factory set to the automatic
position, suitable for most water conditions. The
setting can be changed to one of 5 manual settings
or left on automatic.
Bridge Thickness Adjustment Mechanism
Purge
setting
1 - Minimum
2Moderate
3Standard
4 - Heavy
5 - Maximum
A - Automatic
Water
Type
RO water or
equivalent
Low TDS
non - RO
water
Use for
typical
water
High TDS
water
Very High
TDS water
Any with
conductivity not
less than 10
microSiemens/cm
To set:
1. Switch the machine OFF by holding the Off
button in until a number or the letter A shows
on the display.
2. Press and release the On button repeatedly
until the number on the display corresponds to
the desired setting.
3. Press and release the Off switch again to
return to the normal control state.
May 2008
Page 10
CU1526, CU2026, CU3030
Service Manual
Use and Operation
Once started, the ice machine will automatically
make ice until the bin is full of ice. When ice level
drops, the ice machine will resume making ice.
Power Status Water De-scale
On
Sanitize
There are four indicator lights at the front of the
control box that provide information on the
condition of the machine.
Manual
Harvest
Clean
Code
Display
Control Operation - See Manual
Code
Description
F . . . . . . . . . . Freeze Cycle
F flashes . . . . Freeze Cycle is Pending
H . . . . . . . . . . Harvest Cycle
H flashes . . . . Manual Harvest
b . . . . . . . . . . Bin is Full
C . . . . . . . . . . Clean Cycle
L . . . . . . . . . . Board Locked
d . . . . . . . . . . Test Mode
O . . . . . . . . . . Off
E . . . . . . . . . . Self Test Failed
1 flashes. . . . Max Freeze - Retrying
1 . . . . . . . . . . . Max Freeze Time Shut Down
2 flashes . . . . Max Harvest - Retrying
2 . . . . . . . . . . Max Harvest Time Shut Down
3 . . . . . . . . . . Slow Water Fill
4 . . . . . . . . . . High Discharge Temp
5 . . . . . . . . . . Sump Temp Sensor Failure
7 . . . . . . . . . . Discharge Temp Sensor Failure
8 flashes . . . Short Freeze - Retrying
8 . . . . . . . . . . . . Short Freeze - Thin ice
All 4 Upper Lights Flashing - Unit Remotely
Locked Out - Contact Leasing Company
Water Light On - Restore water supply to
machine.
De-Scale Light On - Clean and sanitize
machine.
Flush Setting - To Change: Depress Off
for 3 seconds. Press On to select purge
(1-5) setting or A for Automatic.
Test Mode - Depress Off for 3 seconds,
then depress Clean for 3 seconds.
Recall Diagnostic Codes - Depress Off
for 3 seconds. Press Harvest repeatedly
to go from most recent to oldest of 10.
Reset from Code 1, 2, 4 or 8 - Depress
Off then Depress On.
Component Operation Indicator Lights
Indicator Lights:
•
•
•
•
Off
Technician Section
Power
Status
Water
De-scale & Sanitize
02-4302-01
Indicator Lights & Their Meanings
Power
Status
Water
De-Scale & Sanitize
Steady Green
Normal
Normal – bin full or making ice
-
-
Blinking Green
Self Test
Failure
Switching on or off
-
-
Blinking Red
-
Diagnostic shutdown or, if making
ice, temperature sensor failure
Lack of
water
-
Yellow
-
-
-
Time to de-scale and
sanitize
Blinking
Yellow
-
-
-
In Cleaning mode
Light off
No power
Switched off
Normal
Normal
All Blinking
Unit remotely locked out – check with leasing company
If the Water light is on, the machine has sensed a
lack of water. Check the water supply to the
Note: Water cooled models, the refrigeration
machine. The water could have been shut off or the system discharge pressure is factory set at 245
water filter cartridges might need to be changed.
PSIG, which should yield a freeze cycle discharge
water temperature of about 105-110 degrees F.
If the De-Scale light is on, the machine has
Adjust if necessary.
determined that it needs to be cleaned. Contact an
authorized Scotsman service agent and have the
machine cleaned, de-scaled and sanitized.
May 2008
Page 11
CU1526, CU2026, CU3030
Service Manual
Control Switches
There is a front on and off switch, located in the top
center of the louvers. Switching this switch Off will
immediately stop the machine. Switching it back on
will cause the machine to start in a timed harvest
cycle.
Power Status Water De-scale
On
Sanitize
Off
Technician Section
Manual
Harvest
Clean
Code
Display
Control Operation - See Manual
Code
Description
F . . . . . . . . . . Freeze Cycle
F flashes . . . . Freeze Cycle is Pending
H . . . . . . . . . . Harvest Cycle
H flashes . . . . Manual Harvest
b . . . . . . . . . . Bin is Full
C . . . . . . . . . . Clean Cycle
L . . . . . . . . . . Board Locked
d . . . . . . . . . . Test Mode
O . . . . . . . . . . Off
E . . . . . . . . . . Self Test Failed
1 flashes. . . . Max Freeze - Retrying
1 . . . . . . . . . . . Max Freeze Time Shut Down
2 flashes . . . . Max Harvest - Retrying
2 . . . . . . . . . . Max Harvest Time Shut Down
3 . . . . . . . . . . Slow Water Fill
4 . . . . . . . . . . High Discharge Temp
5 . . . . . . . . . . Sump Temp Sensor Failure
7 . . . . . . . . . . Discharge Temp Sensor Failure
8 flashes . . . Short Freeze - Retrying
8 . . . . . . . . . . . . Short Freeze - Thin ice
All 4 Upper Lights Flashing - Unit Remotely
Locked Out - Contact Leasing Company
Water Light On - Restore water supply to
machine.
De-Scale Light On - Clean and sanitize
machine.
Flush Setting - To Change: Depress Off
for 3 seconds. Press On to select purge
(1-5) setting or A for Automatic.
Test Mode - Depress Off for 3 seconds,
then depress Clean for 3 seconds.
Recall Diagnostic Codes - Depress Off
for 3 seconds. Press Harvest repeatedly
to go from most recent to oldest of 10.
Reset from Code 1, 2, 4 or 8 - Depress
Off then Depress On.
Component Operation Indicator Lights
The controller also has on and off switches, which
can also switch the machine on and off, but their
operation is different:
02-4302-01
To switch the machine OFF, push and release the
Off button. The machine will shut off at the end of
the next cycle. To shut the machine off
immediately, push and hold the Off button for 3
seconds.
Note: A Component Indicator Light switches ON to
indicate that the component is operating.
To switch the machine ON, push and release the
On button. The machine will go through a start up
process and then resume ice making.
Note: There are two Curtain Switch lights, SW1 and
SW2. These single plate models have one curtain
switch light on all the time, as a curtain switch light
is ON when a curtain is either open or not present.
May 2008
Page 12
CU1526, CU2026, CU3030
Service Manual
Cuber System Information
Overall System Type:
• Refrigeration: Mechanical, either air cooled or water cooled
• Water System: Inlet water float valve fills reservoir continuously. Purge solenoid valve opens to
•
•
•
•
•
•
discharge some reservoir water once per cycle.
Control System: Electronic
Harvest cycle sensor: Conductivity probe
Water full/empty sensor: Conductivity probe
Bin Control: Curtain Switch
Ice type: Unified
Harvest system: Hot gas defrost with mechanical assist
Electrical Components:
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Compressor
Contactor
Water Pump
Purge or purge Valve
Fan Motor(s)
Fan motor pressure control
High pressure cut out
Harvest Assist Solenoid
Hot Gas Valve
Controller
Transformer – 12v AC for the controller only
Water Sensor
Ice Thickness Sensor
Curtain Switch
May 2008
Page 13
CU1526, CU2026, CU3030
Service Manual
Controller Information
Machine Indicator Lights
•
•
•
•
Power
Status
Water
Clean
Code Display
Main codes - automatically displayed
F
F
. . . . . . . Freeze Cycle
flashes. . . . Freeze Cycle is Pending
H
. . . . . . . Harvest Cycle
H
flashes . . . Manual Harvest
b
. . . . . . . Bin is Full
C
. . . . . . . Clean Cycle
L
. . . . . . . Board Locked
d
. . . . . . . Test Mode
O
. . . . . . . Off
E
. . . . . . . Self Test Failed
1
1
2
flashes. . . . Max Freeze - Retrying
. . . . . . . Max Freeze Time Shut Down
flashes. . . . Max Harvest - Retrying
2
. . . . . . . Max Harvest Time Shut Down
3
. . . . . . . Slow Water Fill
4
. . . . . . . High Discharge Temp
5
. . . . . . . Sump Temp Sensor Failure
7
. . . . . . . Discharge Temp Sensor Failure
8
flashes. . . . Short Freeze - Retrying
8
. . . . . . . Short Freeze - Thin ice
Setting Codes - requires push button sequence for access
Water Purge Settings
A, 1, 2, 3, 4, 5
De-scale Interval Settings
6, 5, 4, 3
May 2008
Page 14
CU1526, CU2026, CU3030
Service Manual
Controller Information
Component Indicator Lights
•
•
•
•
•
•
•
•
•
•
•
Condenser Fan / Aux
Water Pump
Purge Valve
Water Solenoid
Hot Gas
Compressor
Ready to Harvest
Sump Empty
Sump Full
Curtain SW1
Curtain SW2
Component Indicator Light Table
System
Indicator Light ON
Condenser Fan / AUX
Fan Motor Powered
Water Pump
Pump Motor Powered
Purge Valve
Purge Valve Opens
Inlet Water Solenoid Valve
Not used this model
Hot Gas
Hot Gas Valve Opens and harvest assist solenoid powered
Compressor
Contactor Closes
Ready to Harvest
Water contacting ice thickness sensor probe
Sump Empty
Open between mid sensor and common
Sump Full
Closed between top probe and mid probe
Curtain Switch
Curtain open
May 2008
Page 15
CU1526, CU2026, CU3030
Service Manual
How It Works - Air Cooled
Freeze Cycle. At start up the controller operates the water pump and purge valve to drain the reservoir.
The float valve refills the reservoir after the purge valve shuts off. When the reservoir has filled, the
compressor and water pump start. After the discharge pressure has increased past the cut in point of the
fan pressure control, the fan motor(s) will begin to operate and warm air will be discharged. The fan
motor will switch on and off as the discharge pressure rises and falls. Water flows over the evaporator as
the refrigeration system begins to remove heat. When the water temperature falls to a preset point, as
measured by the water temperature sensor, the controller shuts off the water pump for 30 seconds. The
freeze cycle resumes when the pump restarts and ice begins to form on the evaporator. As it forms, the
water flowing over the ice moves closer and closer to the metal tip of the ice thickness sensor. When it
comes into contact with the sensor for a few continuous seconds, that signals the controller that the
freeze cycle is complete.
The controller may shut the air cooled fan motor off for a variable period of time to build up heat for
harvest. This is dependant upon the temperature of the discharge line sensor.
Harvest Cycle. When the harvest cycle begins, the controller shuts off the fan motor, switches on the
hot gas valve, and through a parallel circuit, the harvest assist solenoid. After a few seconds the purge
valve opens and water is drained from the reservoir. Based on either the automatic purge or manual
purge setting, the pump and purge valve will be switched off at a time determined to have drained
enough water for that setting. The float valve will open to fill the reservoir anytime during the reservoir
drain cycle. Harvest continues as the hot discharge gas flows into the evaporator serpentine, heating up
the evaporator. At the same time the harvest assist solenoid is pushing against the back of the ice slab.
When the ice releases from the evaporator, it harvests as a unit, and the harvest assist probe provides
some additional force to push it off. When the ice falls off it will force the curtain open. An open curtain
during the harvest cycle signals the controller that the evaporator has released its ice, and the controller
will terminate harvest. If the curtain remains open, the controller will shut the machine down on bin full.
Anytime harvest is complete the hot gas valve and harvest assist solenoid are shut off. The harvest
assist solenoid pin returns to its normal position by spring pressure.
If the curtain re-closes after harvest, the freeze cycle will restart.
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How It Works - Water Cooled
Freeze Cycle. At start up the controller operates the water pump and purge valve to drain the reservoir.
The float valve refills the reservoir after the purge valve shuts off. When the reservoir has filled, the
compressor and water pump start. After the discharge pressure has increased past the set point of the
water regulating valve, the water regulating valve will open and warm water will be discharged out the
condenser drain. The water regulating valve will modulate to maintain a relatively constant discharge
pressure. Water flows over the evaporator as the refrigeration system begins to remove heat. When the
water temperature falls to a preset point, as measured by the water temperature sensor, the controller
shuts off the water pump for 30 seconds. The freeze cycle resumes when the pump restarts and ice
begins to form on the evaporator. As it forms, the water flowing over the ice moves closer and closer to
the metal tip of the ice thickness sensor. When it comes into contact with the sensor for a few continuous
seconds, that signals the controller that the freeze cycle is complete.
Harvest Cycle. When the harvest cycle begins, the controller switches on the hot gas valve, and through
a parallel circuit, the harvest assist solenoid. After a few seconds the purge valve opens and water is
drained from the reservoir. Based on either the automatic purge or manual purge setting, the pump and
purge valve will be switched off at a time determined to have drained enough water for that setting. The
inlet water float valve will open to fill the reservoir anytime during the reservoir drain cycle. Harvest
continues as the hot discharge gas flows into the evaporator serpentine, heating up the evaporator. At
the same time the harvest assist solenoid is pushing against the back of the ice slab. When the ice
releases from the evaporator, it harvests as a unit, and the harvest assist probe provides some
additional force to push it off. When the ice falls off it will force the curtain open. An open curtain during
the harvest cycle signals the controller that the evaporator has released its ice and the controller will
terminate harvest. If the curtain remains open, the controller will shut the machine down. Anytime
harvest is complete the hot gas valve and harvest assist solenoid are shut off. The harvest assist
solenoid pin returns to its normal position by spring pressure.
If the curtain re-closes after harvest, the freeze cycle will restart
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Electrical Sequence - Air or Water Cooled
Power connected, unit previously switched Off.
Control board does a self check. If the self check fails, the unit displays an E and no further action will
occur.
If the self check passes, the controller will display a 0, the curtain light(s) will be ON and the Power and
Sump Empty lights will be ON.
Pushing and releasing the On button will start the ice making process.
The display will begin to blink F. The component indicator lights will switch on and off to match the
following process:
• The purge valve opens and the water pump starts to empty the reservoir. This is done to discharge
any excess water from ice melting into the reservoir.
• The hot gas valve and the harvest assist solenoid are energized.
• The float valve will open to fill the reservoir. The water valve can open any time the water level is
low.
• After a few seconds the purge valve closes and the pump shuts off.
• When the reservoir is full the compressor switches on. Five seconds after the compressor starts
the hot gas valve and the harvest assist solenoid are de-energized.
Light Information: The display shows a non-blinking F. The Power and Status Lights will be Green. The
compressor, fan motor, water pump, sump full and one or two curtain switch lights will be ON.
The air cooled model's fan motor will start to turn when the discharge pressure has built up to the fan
pressure control's cut in point. This is about 15 seconds after the compressor starts.
The Freeze cycle continues. The compressor, water pump, fan motor and curtain indicator lights will be
ON. When the reservoir water temperature falls to a certain preset point, the water pump will shut off for
30 seconds. This is the anti-slush period. At this time the controller checks the conductivity of the water
in the reservoir for the auto-purge feature. After the water pump restarts the Sump Full light will go out
and neither sump lights will be on for the rest of the freeze cycle.
When the ice has built up enough so that the water flowing over the evaporator comes into continuous
contact with the ice level sensor, the Ready to Harvest light will begin to blink on and off. When it has
been On continuously for 5 seconds, the controller will switch the machine into a Harvest cycle.
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Electrical Sequence - Air or Water Cooled (continued)
Indicator Information: The display shows a non-blinking H. The Power and Status Lights will be Green.
The compressor, hot gas valve and one or two curtain switch lights will be ON. After a few seconds the
water pump, purge valve and inlet water valve lights will come on.
The fan motor(s) shut off and remain off throughout the harvest cycle.
The harvest assist solenoid is connected in parallel with the hot gas valve. Although it is energized
throughout the harvest cycle, its piston does not move until the ice has become partially loosened from
the evaporator plate by the action of the hot refrigerant gas passing through the evaporator serpentine.
The water pump and purge valve will shut off when the purge level setting time has been reached, either
the manual time or the automatic time. The inlet water valve will remain on until it fills the reservoir. The
Ready to Harvest light will switch Off when the ice falls from the evaporator.
Harvest continues until the ice slab is ejected from the evaporator and falls, opening the curtain. When
the curtain opens, the magnetic reed curtain switch opens, breaking the circuit to the controller. If the
curtain re-closes within 30 seconds, the controller switches the machine back into another freeze cycle.
If the curtain switch remains open, the controller shuts the machine down and puts it into a standby
position.
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Electrical Component Details
Compressor
• Operated by the compressor contactor. Uses PTCR and run capacitor.
Contactor
• Operated by the controller and the high pressure cut out switch. Line voltage coil. When energized
the Compressor indicator light will be ON.
Water Pump
• Operated by the controller. When energized, the Water Pump indicator light will be ON.
Purge Valve
• Operated by the controller. Line voltage coil. When energized, the Purge Valve indicator light will
be ON. Energized for a time during harvest.
Fan Motor(s)
• Operated by the controller and the fan pressure control. Can cycle on and off in the freeze cycle,
always off during harvest. When the controller has energized it, the indicator light will be ON but
the fan will not turn unless the discharge pressure is high enough to close the high pressure
control.
• Fan(s) may shut off near the end of the freeze cycle to build up heat for harvest. Time of shut off
depends upon available heat, as measured by the discharge temperature.
High pressure cut out
• All models have a high pressure cut out switch that shuts the power off to the compressor
contactor if the discharge pressure is too high. It is an automatic reset.
Harvest Assist Solenoid
• Operated by the controller in parallel with the hot gas valve. Cycles on and off at the beginning of a
restart. Energized throughout the harvest cycle. Line voltage coil.
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Electrical Component Details - continued
Hot Gas Valve
• Operated by the controller in parallel with the harvest assist solenoid. Cycles on and off at the
beginning of a restart. Energized throughout the harvest cycle. Line voltage coil.
Controller
• Senses ice thickness, water conductivity, water temperature, discharge temperature. Controls
compressor contactor, fan motor, water pump, hot gas valve, purge valve, harvest assist solenoid.
Indicates status and component operation. 12 volt.
Transformer
• 12 volt secondary, supplies power to controller only.
Water Sensor
• Three probe conductivity sensor. Used for WaterSense system.
Ice Thickness Sensor
• Single wire conductivity sensor. Circuit made from controller to ground to controller when water
contacts a probe suspended over ice plate. Signals ready for harvest.
Curtain Switch
• Magnetic reed switch. Normally open, switch is closed when magnet is nearby. Switch can be
connected to either J8 or J7 of controller. Curtain may be removed in the freeze cycle without
affecting controller operation. Curtain removed during harvest will cause the controller to terminate
harvest and shut the unit off.
Water temperature sensor
• Thermistor inserted into the water pump discharge hose. Reported temperature used by the
controller to determine anti-slush cycle start time.
Discharge temperature sensor.
• Thermistor attached to the discharge line near the compressor. Reported temperature used by the
controller to determine end-of-cycle-fan-off-delay time. If discharge temperature exceeds a preset
maximum, controller will shut the machine off.
Note: Controller will operate machine in a default mode with thermistors disconnected from the controller.
Diagnostic code #5 or 7 will be displayed during that time.
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Refrigeration & Water Systems
Refrigerant: R-404A
Compressor: Copeland or Tecumseh hermetic by model
Expansion valve: Non adjustable, internally equalized
Hot gas valve: Pilot operated, line voltage coil.
Condensers: Forced draft air, counterflow water. All air cooled models have left side air inlet. All air
cooled models exhaust air out the right front.
Air filters: Mounted in left front grill and under the base on the CU3030.
Fan pressure control. All AC. Controls fan motor operation in the freeze cycle.
High pressure cut out. All models.
Evaporator: Unified cell plate. Nickel plated copper.
• Small cube: 7/8" high x 7/8" deep x 3/8" wide
• Medium cube: 7/8" high x 7/8" deep x 7/8" wide
Water System
Float fed type. Water reservoir contains partial water charge, which is replenished during each ice
making cycle.
Water valve: Float valve. Water level to be about 1 inch deep at the left end of the reservoir.
Pump: Unsealed pedestal type, twist-release mounting
Water purge valve: Solenoid type. Opens to purge water during harvest cycle.
Water Sensor: Three probe conductivity.
Distributor: ABS plastic. Evenly distributes water over the evaporator surface. Slides off the evaporator
top. Removable cover for ease of cleaning.
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Control Operation
Standard control:
• Electronic controller operating from a 12 AC volt power supply. Will operate within a voltage range
•
•
•
•
•
•
•
•
•
•
between 10 and 15.5.
Indicator lights, four visible on outside of control box: Power, Status, Water, De-scale/Sanitize.
Accessible On - Off switch. Switch makes or breaks power to the controller.
Code Display: Displays letters and numbers to indicate cycles and diagnostic codes.
Manual Harvest switch: Use to trigger harvest at any time.
Clean switch: Use to initiate and finish the de-scale or sanitizing cycles.
Component Operation Indicator Lights: Indicate the status of certain components; water level;
ready for harvest; curtain switch position.
Power Light: On when power is being supplied to the controller.
Status Light: Green when machine is in ice making mode and is operating correctly. Blinks red
when a machine malfunction has been detected.
Water Light: Blinks red when reservoir does not fill within allowed time period.
De-scale / sanitize: Yellow when the controller has determined it is time to de-scale and sanitize
the machine. Use clean process to reset light. Time is determined by power up time and
controller's setting. Standard setting is 6 months. See adjustment process
Controller Connections:
•
•
•
•
•
•
•
•
•
•
•
J1 – Ground and Power Supply
J2 – High voltage power harness to loads
J3 – Factory use
J4 – Optional board connector
J5 - Communications port
J6 – Thermistor connection
J7 – Curtain switch
J8 – Curtain switch
J9 – Water sensor
J10 – Ice thickness sensor
J11 – Bin thermostat. Not applicable to this model..
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Control Safeties
Max freeze time – 84 minutes
When exceeded, the controller will attempt another freeze cycle. If the next cycle's freeze time is less
than maximum, the control will continue normal ice making. If the next freeze cycle was too long, the
control will again attempt another freeze cycle. If the freeze cycle is too long three consecutive cycles,
the controller will shut the unit off and it must be manually reset.
Min freeze time – 6 minutes
If the controller switches the machine into harvest within 20 seconds of the minimum freeze time, the
controller will harvest for a preset time and does not stop if the curtain switch opens. If this occurs again
in the next three cycles, the machine will shut down and must be manually reset.
Max harvest time – 3.5 minutes
If the harvest cycle has continued for 3.5 minutes without the curtain opening, the controller will shut the
machine off for 50 minutes and then restart. If there is another the machine will shut the machine off for
another 50 minutes and then restart. If it fails a third consecutive time the controller will shut the machine
down and must be manually reset.
•
•
•
•
Time between resets – 50 minutes
Number of automatic resets – 2
Max discharge temp – 250 degrees F.
Time interval between cleanings – 6 months power on time - adjustable in one month increments,
can be set at 6, 5, 4 or 3 months of power up time.
• Manual harvest time – 3 minutes
• Minimum compressor off time – 4 minutes
• Continuous Run Time Maximum Cycles - 200
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Restarts
Power Interruption
The controller will automatically restart the ice machine after adequate voltage has been restored. This
also occurs after the on-off switch has been cycled.
• H blinks on code display
• Status indicator light blinks
• Reservoir is drained and refilled
Default harvest is initiated. The curtain switch does not have to open to terminate harvest, harvest will
continue until the default harvest time expires. Default harvest time is 3 minutes. The machine will then
return to a normal freeze cycle.
Water Interruption
• Water must fill the reservoir within the pre-set time period. If it does not, the controller will all ice
making to proceed. The water and status lights will blink and code 3 will be displayed. Controller
will automatically check for water every 20 minutes and restart when the reservoir is full.
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Control Button Use (from standby - status light off)
Set purge level, 1-5 (1 is minimum, 5 is maximum) or Automatic:
• Hold off button in for 3 seconds. Release.
• Press and release the On button to cycle through and select one of the five purge settings or to
use the Automatic setting.
Recall diagnostic code:
• Hold off button in for 3 seconds. Release.
• Press and release the Harvest button to cycle through each of the last 10 error codes from most
recent to oldest.
Clear diagnostic code:
• Hold Clean and Harvest buttons in for 3 seconds to clear all prior codes.
Reset control:
• Depress and release Off, then depress and release On
Start Test Mode:
• Hold Off button in for 3 seconds. Release.
• Hold Clean button in for 3 seconds. Release.
Lock / Unlock control:
• Hold On button in for 3 seconds, keep holding then press and release Off twice.
Empty reservoir:
• Shut off water supply.
• Hold Clean button in for 3 seconds. Release. Pump and purge valve will be ON for 30 seconds.
Repeat as needed.
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Test Mode:
• Depress Off for 3 seconds, release. Then depress Clean for 3 seconds.
• At 30 seconds the WP will turn on. You will be able to see and hear the water running over the
plate. After 10 seconds the PV and HGV will turn on. Water will be purging from the machine.
After 10 more seconds the compressor will start. 5 seconds later the HGV will close. The
compressor will run for a total of 20 seconds. After which everything will turn off for 5 seconds.
After that time the HGV will open and you’ll be able to hear the hissing as the pressure is
equalized. 10 seconds later the fan will turn on (if air cooled and fan control jumped). After 10
seconds all will be off and the output test will be complete.
Test Mode Sequence Table - Air or Water Cooled
Time (seconds)
On
Off
0
-
WP, HGV, Comp, Fan, PV
30
WP - 10 seconds
HGV, Comp, Fan, PV
40
WP, PV, HGV - 10 seconds
Comp, Fan
50
HGV, Comp - 5 seconds
WP, Fan, PV
55
Comp - 15 seconds
HGV, WP, Fan, PV
70
None - 5 seconds
All
75
HGV - 10 seconds
WP, Comp, Fan, PV
85
Fan - 10 seconds
HGV, WP, Comp, PV
95
None
All – Test Complete
Change De-Scale Notification Interval
Like the others, this feature is accessible only from standby (Status Light Off).
•
•
•
•
Press and hold harvest button for 3 seconds.
This will allow control to enter Time to Clean Adjustment State.
Display current time to clean months on 7 segment display.
Pressing clean button repeatedly will cycle through one of 4 possible settings:
6 months (4380 hours) (default)
5 months (3650 hrs)
4 months (2920 hrs)
3 months (2190 hrs)
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Service Diagnosis
No ice
Problem
Likely Cause
Probable Solution
No power to unit
Power disconnected
Check breaker or fuse. Reset or
replace, restart and check
Transformer open
Replace transformer
ON-OFF Switch open or set at OFF
Switch to ON or replaced switch
Water shut off
Restore water supply
Water leak
Check purge valve, curtain, sump,
pump hose
Air filter clogged
Clean air filter
Dirty condenser
Clean condenser
Restricted location, intake air too
hot
Have machine moved
Ice thickness sensor dirty or
disconnected
Check ice thickness sensor probe
Water distributor dirty
Remove and clean water
distributor
Inlet water valve leaks through
during freeze
Check inlet water valve
Connected to hot water
Check for bleed thru from / missing
check valve in building water
supply
Incomplete harvest
Check harvest system
High pressure cut out opened
Air cooled ,check fan motor
pressure control, check fan motor,
check controller using test mode
No power to controller
Shut down on maximum
water fill time
Shut down on maximum
freeze time
Water cooled, check for water
interruption
Fan motor pressure control open
Check fan pressure control
Fan motor not turning
Check fan motor, check fan blade,
check controller using test mode
Water pump not pumping
May 2008
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Check pump motor, check
controller using test mode
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Service Manual
Service Diagnosis
Problem
Likely Cause
Probable Solution
Pump hose disconnected
Check hose
Check compressor contactor,
check controller using test mode
Compressor not operating
Check compressor start
components, check PTCR
resistance and temperature
Check compressor voltage
Check compressor windings
Shut down on maximum
freeze time
Low refrigerant charge
Add some refrigerant and restart
unit. If cycle time improves, look for
leak.
Hot gas valve leaks through during
freeze
Check hot gas valve for hot outlet
during freeze
Thermostatic expansion valve bulb
loose
Check bulb
Thermostatic expansion valve
producing very low or very high
superheat
Check evaporator superheat,
change TXV if incorrect
Compressor inefficient
Check compressor amp draw, if
low and all else is correct, change
compressor
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Service Diagnosis
Problem
Shut down on maximum
harvest time
Likely Cause
Probable Solution
Ice bridge thickness too small, not
enough ice to open curtain
Check and adjust if needed
Ice bridge thickness too large, ice
frozen to evaporator frame
Check and adjust if needed
Purge valve does not open, water
melts ice bridge, not enough ice to
open curtain
Check purge valve
Incomplete ice formation
Check water distributor for partially
plugged holes
Curtain out of position
Check curtain for swing restriction
Curtain switch does not open when
curtain does
Check switch with ohmmeter
Machine in very cold ambient
Move machine to a warmer
location
Hot gas valve does not open
Check hot gas valve, check
controller using test mode
Harvest assist probe out of position
– ejector pin not retracted
Check harvest assist mechanism –
spring should retract pin
Damaged evaporator
Check evaporator surface
Fan motor stays on during harvest
Check controller using test mode
Grounded ice thickness sensor
Check sensor for dirt and position.
Clean and check gap to evaporator
surface.
Water flow incorrect near sensor
Check water distributor for proper
assembly, attachment and for
scale build up. Correct as needed.
Shut down on minimum
freeze time
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Service Diagnosis - Low ice making capacity - air cooled
Problem
Long freeze cycle
Long Harvest Cycle
False bin full signal
Likely Cause
Probable Solution
Dirty air filter
Clean filter
Dirty condenser
Clean condenser
Hot ambient
Reduce room air temperature
Water leak
Check purge valve, check curtain
Water inlet valve leaks through
Check inlet valve
Low on refrigerant
Add refrigerant, if cycle time drops,
check for leak
Incorrect superheat
Check evaporator superheat, if
significantly low or high, replace
TXV
Fan(s) cycle on and off
Check pressures fans cycle at.
Replace fan pressure switch if too
low
Dirty evaporator
De-scale water system
No harvest assist
Check harvest assist solenoid
Bridge thickness too big
Check and adjust bridge thickness
Machine in very cool ambient
Increase room temperature
Ice jammed in between curtain and
sump
Clear ice away
Curtain does not close correctly
Check curtain for proper swing
Makes excessive noise - air cooled
Problem
Likely Cause
Probable Solution
Blade is bent
Replace fan blade
Fan motor mount is broken
Replace motor mount
Compressor vibrates
Mounting bolts loose
Tighten bolts
Water pump vibrates
Pump bearings worn
Replace pump
Panels vibrate
Mounting screws loose
Tighten screws
Fan blade vibrates
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Cleaning, Sanitation and Maintenance
This ice system requires three types of maintenance:
• Remove the build up of mineral scale from the ice machine’s water system and sensors.
• Sanitize the ice machine’s water system and the ice storage bin.
• Clean or replace the air filter and clean the air cooled condenser (air cooled models only).
It is the User’s responsibility to keep the ice machine and ice storage bin in a sanitary condition. Without
human intervention, sanitation will not be maintained. Ice machines also require occasional cleaning of
their water systems with a specifically designed chemical. This chemical dissolves mineral build up that
forms during the ice making process.
Sanitize the ice storage bin as frequently as local health codes require, and every time the ice machine
is cleaned and sanitized.
The ice machine’s water system should be cleaned and sanitized a minimum of twice per year.
Note: The front On/Off switch must be in the ON
position during the scale removal and sanitation
process.
7. Allow the ice machine scale remover to
circulate in the water system for at least 10
minutes.
8. Push and release the Clean button again. The
yellow Clean light will be on continuously and
the machine will drain and refill the reservoir
repeatedly to purge out the ice machine scale
remover and residue.
1. Remove the left front louvered panel.
2. Remove the top panel.
3. If the machine is operating, push and release
the Harvest button. When the machine
9. Allow the drain and refill process to continue for
completes the Harvest cycle it will stop. If the
at least 20 minutes.
bin is full (b shows in display) push and release
the Off button.
10. Push and release the Off button. The clean
cycle will stop and the display will show O.
4. Remove all ice from the storage bin
5. Push and release the Clean button. The yellow
Clean light will blink and the display will show
C. The machine will drain the reservoir and refill
it. Go onto the next step when the reservoir has
filled.
Note: If unit has not been de-scaled for an
extended period of time and significant mineral
scale remains, repeat steps 5-10.
11. Mix a cleaning solution of 1 oz of ice machine
scale remover to 12 ounces of water.
Ice machine cleaner contains 12. Locate curtain, push in on edge of curtain by
acids. Acids can cause burns.
pivot pin to release it. Pull curtain out of
If concentrated cleaner
machine.
comes in contact with skin,
flush with water. If swallowed,
13. Remove water distributor from ice machine.
do NOT induce vomiting.
Inspect distributor for restricted orifice holes.
Give large amounts of water
or milk. Call Physician
Be sure all holes are fully open.
immediately. Keep out of the
reach of children.
6. Pour 8 ounces of Scotsman Clear 1 ice
machine scale remover into the reservoir.
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10. Push and release the On button to resume ice
making.
11. Return the top panel and front louvered panel
to their normal position and secure with the
original fasteners.
Air cooled condenser filter
Inspect Orifice Holes
1. Remove left front grill .
Inspect Water Distributor
2. Wash the dust and grease off the filter.
1. Locate ice thickness sensor. Squeeze
mounting legs together to release sensor.
Wash the metal surfaces of the sensor and the
adjustment screw with ice machine scale
remover solution. Also wash the water
distributor and curtain with the ice machine
cleaner solution.
3. Return it to its original position.
Do not operate the machine without the filter in
place except during cleaning.
Air cooled condenser
2. Locate water sensor. Squeeze catches
together and pull up to remove sensor. Wash
metal surfaces of sensor with ice machine
scale remover solution.
3. Mix a solution of sanitizer.
If the machine has been operated without a filter
the air cooled condenser fins will need to be
cleaned.
They are located under the fan blades. The
services of a refrigeration technician will be
required to clean the condenser.
Note: A possible sanitizing solution may be made
by mixing 1 ounce of liquid household bleach with 2
Exterior Panels
gallons of warm (95-115oF.) potable water.
4. Thoroughly wash all surfaces of the ice
thickness sensor, water level sensor, curtain
inside of the top panel and the water distributor
with the sanitizer solution.
The front and side panels are durable stainless
steel. Fingerprints, dust and grease will require
cleaning with a good quality stainless steel cleaner.
Water filters
5. Wash all interior surfaces of the freezing
compartment, including storage bin liner with
the sanitizer solution.
6. Return water level sensor, ice thickness
sensor, water distributor and curtain to their
normal positions.
If the machine has been connected to water filters,
check the cartridges for the date they were
replaced or for the pressure on the gauge. Change
cartridges if they’ve been installed more than 6
months or if the pressure drops too much when the
ice machine fills with water.
7. Push and hold the clean button to drain the
reservoir. Push and release the clean button
again and when the purge valve indicator light
goes out, immediately pour the remaining
cleaning solution into the reservoir.
8. Circulate the sanitizer solution for 10 minutes,
then push and release the Clean button.
9. Allow the water system to be flushed of
sanitizer for at least 20 minutes, then push and
release the Off button.
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Test Procedures - Sensors
All electrical components in this ice machine can be diagnosed with a volt-ohmmeter.
Curtain Switch:
1. Test using the controller’s indicator lights.
Observe SW1 or SW2. Open and close the curtain.
When the curtain is opened, the SW light will be
ON. When the curtain gets to within a half inch of
closing (at the switch) the SW light will go OUT.
2. Test with an ohmmeter. Disconnect electrical
power. Open the control box cover. Unplug the
curtain switch lead from the controller. Connect an
ohmmeter to the leads of the switch. Open and
close the curtain. When the curtain is closed, the
switch is closed and there will be continuity. When
the curtain is open, the switch is open and the
circuit will be open.
3. Test the controller’s curtain switch circuit by
jumping the connectors on J1 or J2 together.
Reconnect electrical power. When jumped, the
matching SW light will go out. When unplugged or
open, the SW light will be ON.
Curtain Switch
Ice Thickness Sensor
1. Test using the controller’s indicator light.
Observe the Ready To Harvest light. Shut the
machine off. Use a wire to connect the metal part
of the Ice Thickness sensor to the evaporator or
simply remove the Ice Thickness Sensor and touch
its metal surface to the metal control box wall. The
Ready for Harvest light should go ON.
2. Test with an Ohmmeter. Disconnect electrical
power. Open the control box cover. Unplug the ice
thickness sensor lead from the controller. Connect
an ohmmeter lead to the ice thickness sensor lead,
touch the other ohmmeter lead to the ice machine
chassis. There must be an open circuit. If there is
continuity, the sensor must be replaced. If there is
no continuity, touch the ohmmeter lead to the metal
part of the ice thickness sensor. There should be
continuity. If open, check the ice thickness sensor
for scale build up. Clean and recheck. If still open,
replace the ice thickness sensor.
3. Test the controller’s ice thickness sensor circuit
by connecting a wire from J10 to ground.
Reconnect electrical power. The Ready for Harvest
light should go ON.
May 2008
Page 34
Ice Thickness Sensor
CU1526, CU2026, CU3030
Service Manual
Sensor Testing
Water Sensor
The water sensor has two functions, the first is to
stop the machine from operating if there is no
water, the second is to sense the conductivity of
the water supply. This test is for sensing that there
is water in the sump.
1. Test using the controller’s indicator lights (sump
empty and sump full). Shut the water supply to the
unit off. With power supplied to the unit, push and
hold the Clean button until water is pumped out of
the reservoir. The sump empty light should be On.
If not, check the water level and repeat the drain
cycle if needed. Then add water, when there is
water in the reservoir, the sump empty light go out.
When that occurs, the sensor and its circuit are
good. The sump full light has no function in this
model.
the harness connector) and compare to the
resistance in the chart for that temperature. Any
reading within 1000 ohms is acceptable.
3. Alternate procedure: Remove both water and
discharge sensors from their places on the ice
machine. Put both into a container of ice water. Put
a thermometer in the water. When the thermometer
is at 32 degrees F., check the resistance of each
sensor. The resistance should be within 1000 ohms
of 32649.
2. Test with an ohmmeter. Disconnect electrical
power. Open the control box cover. Unplug the
connector at J9. Locate water level sensor and
remove it from the sump cover. Test 1: Place one
lead of the ohmmeter on the longest probe and the
other on the controller end of the red wire, there
should be continuity. Test 2: Place one lead on the
controller end of the white wire and the other on the
mid-length probe, there should be continuity. Test
3: Place on lead on the controller end of the black
wire and the other on the shortest probe, there
should be continuity. If not, clean the probes and
recheck.
Temperature Sensors
1. Check controller. If the sensor calibration is
completely out of range, the code display will read
either 5 or 7.
2. Check with an ohmmeter. Open control box
cover, unplug sensor from J6. Water temperature
probe: Measure the temperature of the water. Push
and release the clean button. Wait one minute.
Measure the resistance of the water probe (two
leads next to the open socket) and compare to the
resistance in the chart for that temperature. Any
reading within 1000 ohms is acceptable. Discharge
sensor: Measure the temperature of the discharge
line as close to the sensor as possible. Measure
the resistance of the discharge temperature sensor
(two leads farthest away from the open socket on
May 2008
Page 35
CU1526, CU2026, CU3030
Service Manual
Thermistors
Deg. F · Ohms
0·
1·
2·
3·
4·
5·
6·
7·
8·
9·
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
85325
82661
80090
77607
75210
72896
70660
68501
66415
64400
62453
60571
58752
56995
55296
53653
52065
50529
49043
47607
46217
44872
43571
42313
41094
39915
38774
37669
36600
35564
34561
33590
32649
31738
30855
30000
29171
28368
27589
26835
26104
25395
24707
24041
23394
22767
22159
21569
20997
20442
19903
19381
Deg. F · Ohms
52 ·
S3 ·
54 ·
55 ·
56 ·
57 ·
58 ·
59 ·
60 ·
61 ·
62 ·
63 ·
64 ·
65 ·
66 ·
67 ·
68 ·
69 ·
70 ·
71 ·
72 ·
73 ·
74 ·
75 ·
76 ·
77 ·
78 ·
79 ·
80 ·
81 ·
82 ·
83 ·
84 ·
85 ·
86 ·
87 ·
88 ·
89 ·
90 ·
91 ·
92 ·
93 ·
94 ·
95 ·
96 ·
97 ·
98 ·
99 ·
100
101
102
103
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
18873
18381
17903
17439
16988
16551
16126
15714
15313
14924
14546
14179
13823
13476
13139
12812
12494
12185
11884
11592
11308
11031
10763
10502
10247
10000
9760
9526
9299
9077
8862
8652
8448
8250
8056
7868
7685
7507
7333
7164
6999
6839
6683
6530
6382
6238
6097
5960
5826
5696
5569
5446
Deg. F. · Ohms
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
5325
5208
5093
4981
4872
4766
4663
4562
4463
4367
4273
4182
4093
4006
3921
3838
3757
3678
3601
3526
3452
3381
3311
3243
3176
3111
3047
2985
2924
2865
2807
2751
2696
2642
2589
2537
2487
2438
2390
2343
2297
2252
2208
2165
2123
2082
2042
2003
1965
1927
1890
1855
May 2008
Page 36
Deg. F.
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
Ohms
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
1819
1785
1752
1719
1687
1655
1624
1594
1565
1536
1508
1480
1453.
1427
1401
1375
1350
1326
1302
1279
1256
1234
1212
1190
1169
1149
1129
1109
1090
1071
1052
1034
1016
998
981
965
948
932
916
901
885
871
856
842
828
814
800
787
774
761
749
737
Deg. F. · Ohms
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
246
249
250
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
724
713
701
690
679
668
657
646
636
626
616
606
597
587
578
569
560
551
543
534
526
518
510
502
495
487
480
472
465
458
451
444
438
431
425
419
412
406
400
394
389
383
377
CU1526, CU2026, CU3030
Service Manual
Test Procedures - Loads
model was equipped with a potential relay, start
capacitor and run capacitor, those should be
replaced with the compressor. Most Scotsman
service compressors include those parts.
Compressor
Electrical Shock
Hazard.
Use extreme caution
while performing
diagnostic
procedures.
Fan motor
1. Test using the controller’s indicator lights.
Note: Fan pressure control connection must be
jumped to perform this test.
Failure to start.
All have resistance start, capacitor run type motors.
Check voltage to compressor at the contactor.
Compare the idle voltage (compressor off) to the
active voltage (compressor starting). The supply
voltage must not be less than the lowest rated
voltage for the ice machine. If the voltage is
correct, proceed to the next step.
Put the controller into test mode (depress Off for 3
seconds then depress Clean for 3 seconds). At the
end of the test cycle, the fan motor will be powered
and the Condenser Fan motor indicator light will be
on. The fan motor should start and run at that time.
If it does not, repeat the test but check the voltage
to the fan motor, it must receive full voltage at the
fan motor lead connection at the end of the test. If
Check starting components. All models use a
there is voltage and the motor does not operate,
PTCR to cut power to the start winding after the
replace the motor. If there is no voltage, check the
compressor has started. Check the PTCR for
resistance. The resistance check must be when the controller high voltage harness connection. The fan
motor lead is the top wire. Check voltage from it to
PTCR is at room temperature – any temperature
ground, at the end of the test, when the fan motor
between 50 and 100.
indicator light is On, there must be voltage from this
pin to ground. Note: high voltage power is supplied
At that temperature resistance should be very low
between 25 and 50 ohms. Also check resistance to to the bottom pin from the contactor line. Refer to
the machine wiring diagram as needed.
ground, it should be infinite. If the PTCR is good,
check the compressor windings.
2. Test using an ohmmeter.
Measure resistance from Common to ground. It
should be infinite. Measure resistance from
Common to Run – compare to the chart. Measure
resistance from Common to Start – compare to the
chart.
Compressor check for high amp draw. Measure
amp draw of starting circuit. If it does not drop off
immediately after start up, the PTCR should be
replaced. It is not practical to check a PTCR for
resistance at high temperatures as the resistance
drops very fast as the PTCR’s temperature falls. If
the compressor is drawing excessive amps but is
operating, the run capacitor may be open.
Disconnect electrical power, discharge the
capacitor and measure its resistance. If open,
replace it. If shorted to ground, replace it.
Disconnect electrical power.
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning diagnostic
procedure.
Unplug fan motor from harness. Measure fan motor
winding resistance. If open, replace the fan motor.
Any time the compressor is replaced, the PTCR
and run capacitor should also be replaced, or if the
May 2008
Page 37
CU1526, CU2026, CU3030
Service Manual
Test Procedures
Water Pump
Purge valve
1. Test using the controller’s indicator lights. Check
the indicator light during the freeze cycle. The light
will be On for all but the 30 second anti-slush
period, so observe the light for one minute. When it
is On, check the water pump, it should be
operating. If not, check voltage to the pump. If low
check the voltage from the controller to ground.
The water pump pin is number 6. If there is voltage
at that pin to ground, but very low voltage at the
pump motor, there must be a broken wire in the
harness. If the voltage is low at pin 6, the controller
should be replaced.
1. Test using the controller’s indicator lights. Shut
unit off by holding the Off button for 3 seconds.
Wait four minutes. Push and release the On button,
observe the Purge Valve indicator light. As the unit
drains the reservoir, the purge valve will be
powered. When it gets power, the indicator light will
be ON. If the purge valve does not open to drain
the reservoir when its indicator light is on, do a
voltage check. Shut the unit down by holding the
Off button in for 3 seconds. Unplug the harness
connection from the purge valve. Wait four
minutes. Push and release the On button to restart
the machine. As the unit drains the reservoir, the
purge valve connection should receive full voltage.
If it does, the purge valve should be replaced. If
there is no voltage, check voltage from the
controller to ground. The purge valve pin is 3
(dump valve on wiring diagram). If there is voltage
from that pin to ground, but low voltage at the valve
harness connection, the harness has a broken wire
or poor connection and must be replaced. If the
voltage to ground is low, the controller should be
replaced.
2. Test using an ohmmeter.
Disconnect electrical power.
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning diagnostic
procedure.
Unplug the water pump motor leads from the
harness. Measure the resistance of the motor
windings. If open, replace the pump. Measure
resistance to ground. If there is any, replace the
pump.
Note: The coil of this valve is internally rectified,
and will normally show infinite resistance when
tested with an ohmmeter.
May 2008
Page 38
CU1526, CU2026, CU3030
Service Manual
Test Procedures
switch will re-close and the contactor coil will be
energized.
Compressor contactor
1. Test using the controller’s indicator lights. When
the unit is in ice making mode the compressor
contactor will have power. Check the Compressor
indicator light, when it is on the compressor
contactor will have pulled in. If it is not, do a voltage
check. Place voltmeter leads on the coil of the
contactor. There should be full voltage . If there is
full voltage present and the contactor has not
pulled in, replace the contactor. If there is no
voltage check if the high pressure cut out is open. If
the high pressure cut out is closed, check for
voltage from the controller to ground. The contactor
pin is 4. Check from 4 to ground when the
compressor indicator light is on. There should be
voltage. If not, replace the controller. If there is
voltage at the controller but not at the contactor
coil, the harness wires or connectors are damaged
and must be replaced.
2. Test using an ohmmeter. Disconnect electrical
power.
To Test Fan Pressure Switch:
A. Attach refrigeration gauge set to high side port.
B. Unplug both wires from fan pressure control. Be
SURE the wire's terminals are wrapped in
electrical tape to prevent short circuits to
ground during the test.
C. Connect ohmmeter to terminals of fan pressure
control..
D. Switch ice machine on, observe pressure that
the pressure control closes at, compare to spec.
Switch unit off, allow system to equalize, observe
pressure the pressure control opens at, compare to
spec.
To Test High Pressure Switch:
A. Attach refrigeration gauge set to high side port.
B. Unplug fan motor or shut water off if water
cooled.
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning diagnostic
procedure.
C. Measure voltage between contactor side
terminal of high pressure control and ground.
D. Switch ice machine on, observe pressure that
Test the coil of the contactor for continuity or shorts the pressure control opens at, compare to spec.
to ground. Replace if open or shorted.
Allow system to equalize, observe the pressure
that the pressure control closes at, compare to
3. Check connections and contacts. Be sure
spec.
connections are tight and that the contacts are not
burnt. Replace any contactor with burnt contacts.
Transformer
Pressure switches
Check secondary voltage, it must be between 10
and 15.5 AC volts. Replace if no voltage is output
or if above or below the acceptable voltage..
There are two pressure switches: Fan and High
Pressure cut out.
Fan. The fan pressure switch will open to shut the
fan motor off at a certain pressure and re-close at a
preset higher pressure.
High pressure cut out. The high pressure cut out
switch will open at a preset pressure, shutting off
power to the compressor contactor. After the
pressure has fallen to another preset level, the
May 2008
Page 39
CU1526, CU2026, CU3030
Service Manual
Test Procedures
Controller
Hot Gas Valve
The controller’s software operation is confirmed if it
is functioning. Execute the test to confirm its
operation of the loads. Illumination of a diagnostic
code (other than E) is not an indication of controller
failure. Each code requires its own diagnosis.
1. Test using the controller’s indicator lights. If the
unit is running, or has been off for more than 4
minutes, push and release the Harvest button. The
Hot Gas indicator light will be on and the hot gas
valve will be energized. The compressor will force
discharge gas into the evaporator inlet, warming it.
If the evaporator inlet does not warm up, do a
Harvest assist solenoid
voltage check. Shut the unit off by holding the Off
button in for 3 seconds. Unplug the high voltage
1. Test using the controller’s indicator lights. Push
harness from the hot gas solenoid. Attach a
and release the Harvest button. The Hot Gas
voltmeter to the harness connector. Wait 4
indicator light will be on. At the same time the
minutes. Push and release the Harvest button.
Harvest Assist Solenoid will be powered. If the ice
on the evaporator is thin, the solenoid will extend. If There should be full voltage at the connector. If
there is and the solenoid does not open, replace
the ice is nearly full sized, the solenoid will press
against the ice until it releases from the evaporator, the solenoid coil. If full voltage is not present, check
voltage at the controller. If there is no voltage,
then the solenoid probe will extend. If the probe
check voltage from the controller to ground. The
extends, the solenoid is good. If not, do a voltage
hot gas pin is 5. If there is voltage from that pin to
check. Unplug the high voltage harness from the
ground, but low voltage at the solenoid harness
harvest assist solenoid. Attach a voltmeter to the
connection, the harness has a broken wire or poor
harness connector. Push and release the Harvest
connection and must be replaced. If the voltage to
button. There should be full voltage at the
ground is low, the controller should be replaced.
connector. If there is and the solenoid does not
extend, replace the solenoid. If full voltage is not
2. Test with an ohmmeter.
present, check voltage at the controller. If there is
no voltage, check voltage from the controller to
ground. The hot gas / harvest assist pin is 5. If
Disconnect electrical power.
there is voltage from that pin to ground, but low
voltage at the solenoid harness connection, the
harness has a broken wire or poor connection and
Electrical Shock
must be replaced. If the voltage to ground is low,
Hazard.
the controller should be replaced.
Disconnect electrical
Note: The coil of this valve is internally rectified, will
normally show infinite resistance when tested with
an ohmmeter.
power before
beginning removal
procedure.
Unplug high voltage harness from hot gas or vapor
valve. Measure resistance of hot gas or vapor
valve coil. If open, replace the coil.
May 2008
Page 40
CU1526, CU2026, CU3030
Service Manual
Technical Information
Pressure Control Information
Cut In (PSIG)
Cut Out (PSIG
Fan Pressure Control
240
190
High Pressure Cut Out AC
390
500
High Pressure Cut Out WC
300
400
Compressor Amp Draws
CU1526
CU2026
CU3030
Voltage
Brand
Base Model
Freeze
Harvest
115
Copeland
ASB14C3E-IAA-302
5 - 5.5
5.6 - 5.9
230/50
Copeland
ASB14C3E-IAZ-202
115
Copeland
ASE24C3E-IAA-302
5.4 - 5.9
6.1 - 6.3
230/60
Copeland
ASE24C3E-IAV-202
230/50
Copeland
ASE24C3E-IAZ-202
115
Tecumseh
AKA9438ZXA
6 - 7.3
7.2 - 7.9
230/60
Tecumseh
AKA9438ZXD
230/50
Tecumseh
AKA9438ZXC
Refrigerant Charge
Model
Charge, R-404A, Oz
CU1526A
12
CU1526W
9
CU2026A
15
CU2026W
9
CU3030A
12
CU3030W
12
May 2008
Page 41
CU1526, CU2026, CU3030
Service Manual
Performance Data, CU1526
CU1526A
Ambient Air Temp., Degrees F.
70
Cycle Time
(minutes)
Water Temp
50
70
80
90
80
36
37
38
39
24
25
26
27
22-23
24
25
26
90
Suction Pressure
(PSIG)
End of Freeze
Harvest
36 - 39
105 - 110
36 - 38
115 - 120
Discharge
Pressure (PSIG)
End of Freeze
Harvest
211
120
260
130
CU1526W
Ambient Air Temp., Degrees F.
70
Cycle Time
(minutes)
80
90
Water Temp
50
70
80
90
Suction Pressure
(PSIG)
End of Freeze
Harvest
Discharge
Pressure (PSIG)
End of Freeze
Harvest
235-250
Batch weight, 3 lb per cycle
May 2008
Page 42
235-250
235-250
CU1526, CU2026, CU3030
Service Manual
Performance Data, CU2026
CU2026A
Ambient Air Temp., Degrees F.
70
Cycle Time
(minutes)
Water Temp
50
70
80
90
80
25
26
27
28
18
19
20
21
16-17
17
18
19
90
Suction Pressure
(PSIG)
End of Freeze
Harvest
33 - 34
100 - 105
35 - 36
125 - 130
Discharge
Pressure (PSIG)
End of Freeze
Harvest
235
135
305
165
CU2026W
Ambient Air Temp., Degrees F.
70
Cycle Time
(minutes)
80
90
Water Temp
50
70
80
90
Suction Pressure
(PSIG)
End of Freeze
Harvest
Discharge
Pressure (PSIG)
End of Freeze
Harvest
235-250
Batch weight, 3 lb per cycle
May 2008
Page 43
235-250
235-250
CU1526, CU2026, CU3030
Service Manual
Performance Data, CU3030
CU3030A
Ambient Air Temp., Degrees F.
70
Cycle Time
(minutes)
Water Temp
50
70
80
90
80
19
20
22
25
14
15
16
17
13
14
15
16
90
Suction Pressure
(PSIG)
End of Freeze
Harvest
25 - 26
84 - 85
29 - 30
100 - 105
Discharge
Pressure (PSIG)
End of Freeze
Harvest
220
170
270
200
CU3030W
Ambient Air Temp., Degrees F.
70
Cycle Time
(minutes)
Water Temp
50
70
80
90
80
90
12-13
15
Suction Pressure
(PSIG)
End of Freeze
Harvest
25-26
80
Discharge
Pressure (PSIG)
End of Freeze
Harvest
235-250
150-160
Batch weight is about 3 lb per cycle.
May 2008
Page 44
25-26
85-90
235-250
235-250
165-175
THIS UNIT MUST
BE GROUNDED.
DISCHARGE
TEMP.
SENSOR
SUMP TEMP.
SENSOR
ICE
THICKNESS
PROBE
WATER
LEVEL
SENSOR
BN
FAN CYCLING PRESSURE
CONTROL SWITCH
(AIR COOLED ONLY)
R
BK
R
W
BK
W
ELECTRONIC
CONTROL
W
W
J6
DUMP
VALVE
WATER
J7
1 2
R/W
1
2
J1
3
4
1 2 3
J9
MOT
PUMP
CURTAIN SWITCH
J8
1 2
J10
J2
SOLENOID
4
3
2
1
8
7
6
5
4
3
2
1
BU
CAUTION:
BN
MOT
FAN
W
BN
BN/W
Y
SEE NAMEPLATE FOR
PROPER VOLTAGE REQUIREMENTS
AND MAXIMUM FUSE SIZE
SEE NOTE 4
HIGH PRESSURE
CONTROL
BK
SOLENOID
HOT GAS
(WHEN 2ND
FAN IS PRESENT)
W
L2
Y
BK
W
LOAD
W/R
W
GN/Y
LINE
TRANSFORMER
SOLENOID
HARV ASSIST
T1
T2
CONTACTOR
L1
O
W
POWER SUPPLY
BK
BN/W
PTCR
W/Y
W/R
RUN
CAP
BK
W
R
GN
Y
S
R
C
BK
EARTH GROUND
GN/Y
O
COMPRESSOR
EXTERNAL
PROTECTOR
CAUTION: PTCR WILL BE HOT.
COMPRESSOR MAY NOT START IF
PTCR IS NOT ALLOWED TO COOL
USE COPPER CONDUCTORS ONLY
MORE THAN ONE DISCONNECT MEANS MAY BE
REQUIRED TO DISCONNECT ALL POWER TO THIS UNIT.
V
W
W
MOT
FAN
RUN WINDING
START WINDING
17-3195-01
*
May 2008
Page 45
*
(AIR COOLED ONLY)
BK
R
ON/OFF
SWITCH
L1
WATER
PUMP
DUMP
VALVE
CONTACTOR T1
DISCHARGE
TEMP
WATER
LEVEL
SENSOR
ON/OFF
SWITCH
TRANSFORMER
HIGH
PRESSURE
CONTROL
SEE NOTE 4
WATER VALVE
HOT GAS VALVE
FAN
MOTOR
FAN
MOTOR
COMPRESSOR
(WHEN APPLICABLE)
(AC ONLY)
RUN
CAP
PTCR
FAN CYCLING
PRESSURE
SWITCH
(A/C ONLY)
CURTAIN
SWITCH 1
CONTACTOR
COIL
HARVEST ASSIST
SOLENOID 1
SWITCH 2
(2 PLATE UNITS ONLY)
ICE
THICKNESS
PROBE
CURTAIN
(AC ONLY)
SUMP
TEMP
ELECTRONIC CONTROL
12V
LINE
N (115/60/1 UNITS)
L2 (230/60/1 UNITS)
CU1526, CU2026, CU3030
Service Manual
Wiring Diagram, CU1526 and CU2026 60 Hz
THIS UNIT MUST
BE GROUNDED.
DISCHARGE
TEMP.
SENSOR
SUMP TEMP.
SENSOR
ICE
THICKNESS
PROBE
WATER
LEVEL
SENSOR
BN
FAN CYCLING PRESSURE
CONTROL SWITCH
(AIR COOLED ONLY)
R
BK
R
W
BK
W
ELECTRONIC
CONTROL
W
W
J6
DUMP
VALVE
WATER
J7
1 2
R/W
1
2
J1
3
4
1 2 3
J9
MOT
PUMP
CURTAIN SWITCH
J8
1 2
J10
J2
SOLENOID
4
3
2
1
8
7
6
5
4
3
2
1
17-3123-01
BU
CAUTION:
BN
MOT
FAN
W
BN
BN/W
Y
SEE NAMEPLATE FOR
PROPER VOLTAGE REQUIREMENTS
AND MAXIMUM FUSE SIZE
SEE NOTE 4
HIGH PRESSURE
CONTROL
BK
SOLENOID
HOT GAS
(WHEN 2ND
FAN IS PRESENT)
W
L2
Y
BK
W
LOAD
W/R
W
GN/Y
LINE
TRANSFORMER
SOLENOID
HARV ASSIST
T1
T2
CONTACTOR
L1
O
W
POWER SUPPLY
BK
BN/W
W/R
PROTECTOR
INTERNAL
PTCR
W/Y
RUN
CAP
W
BK
R
TERMINAL BOX
EARTH GROUND
COMPRESSOR
GN
GN/Y
O
CAUTION: PTCR WILL BE HOT.
COMPRESSOR MAY NOT START IF
PTCR IS NOT ALLOWED TO COOL
USE COPPER CONDUCTORS ONLY
MORE THAN ONE DISCONNECT MEANS MAY BE
REQUIRED TO DISCONNECT ALL POWER TO THIS UNIT.
V
W
W
MOT
FAN
*
May 2008
Page 46
*
(AIR COOLED ONLY)
BK
R3
C1
S2
Y
R
ON/OFF
SWITCH
L1
WATER
PUMP
DUMP
VALVE
CONTACTOR T1
DISCHARGE
TEMP.
WATER
LEVEL
SENSOR
ON/OFF
SWITCH
TRANSFORMER
HIGH
PRESSURE
CONTROL
SEE NOTE 4
WATER VALVE
HOT GAS VALVE
FAN
MOTOR
COMPRESSOR
(WHEN APPLICABLE)
(AC ONLY)
FAN
MOTOR
RUN
CAP.
PTCR
FAN CYCLING
PRESSURE
SWITCH
(A/C ONLY)
CURTAIN
SWITCH 1
CONTACTOR
COIL
HARVEST ASSIST
SOLENOID 1
SWITCH 2
(2 PLATE UNITS ONLY)
ICE
THICKNESS
PROBE
CURTAIN
(AC ONLY)
SUMP
TEMP.
ELECTRONIC CONTROL
12V
LINE
N (115/60/1 UNITS)
L2 (230/60/1 UNITS)
CU1526, CU2026, CU3030
Service Manual
Wiring Diagram, CU3030 60 Hz
THIS UNIT MUST
BE GROUNDED.
DISCHARGE
TEMP.
SENSOR
SUMP TEMP.
SENSOR
ICE
THICKNESS
PROBE
WATER
LEVEL
SENSOR
BN
FAN CYCLING PRESSURE
CONTROL SWITCH
(AIR COOLED ONLY)
R
BK
R
BK
W
W
ELECTRONIC
CONTROL
W
W
J6
DUMP
VALVE
WATER
J7
1 2
R/W
1
2
J1
3
4
1 2 3
J9
MOT
PUMP
CURTAIN SWITCH
J8
1 2
J10
J2
SOLENOID
4
3
2
1
8
7
6
5
4
3
2
1
17-3196-01
BU
CAUTION:
BN
W
BN
BN/W
SEE NAMEPLATE FOR
PROPER VOLTAGE REQUIREMENTS
AND MAXIMUM FUSE SIZE
HIGH PRESSURE
CONTROL
(WATER COOLED ONLY)
Y
BK
SOLENOID
HOT GAS
(WHEN 2ND
FAN IS PRESENT)
W
W
L2
T2
Y
BK
W
SOLENOID
HARV ASSIST
T1
POWER SUPPLY
BK
L1
CONTACTOR
FUSE (3A)
BN/W
W/R
W
GN/Y
PTCR
W/Y
RUN
CAP
O
W/R
BK
W
R
GN
5
6
Y
BK
BK
2
9
S
R
C
BK
EARTH GROUND
GN/Y
4
TRANSFORMER
7
1 LINE
230V
12V
10 LOAD
COMPRESSOR
EXTERNAL
PROTECTOR
CAUTION: PTCR WILL BE HOT.
COMPRESSOR MAY NOT START IF
PTCR IS NOT ALLOWED TO COOL
USE COPPER CONDUCTORS ONLY
MORE THAN ONE DISCONNECT MEANS MAY BE
REQUIRED TO DISCONNECT ALL POWER TO THIS UNIT.
V
W
W
MOT
FAN
RUN WINDING
START WINDING
MOT
FAN
*
May 2008
Page 47
*
(AIR COOLED ONLY)
BK
O
R
ON/OFF
SWITCH
L1
CONTACTOR T1
WATER
PUMP
DUMP
VALVE
12V
HIGH
PRESSURE
CONTROL
(WC ONLY)
WATER VALVE
HOT GAS VALVE
FAN
MOTOR
COMPRESSOR
(WHEN APPLICABLE)
(AC ONLY)
FAN
MOTOR
RUN
CAP.
PTCR
FAN CYCLING
PRESSURE
SWITCH
(A/C ONLY)
CURTAIN
SWITCH 1
CONTACTOR
COIL
HARVEST ASSIST
SOLENOID 1
.33
uF
SWITCH 2
(2 PLATE UNITS ONLY)
ICE
THICKNESS
PROBE
CURTAIN
(AC ONLY)
SUMP
TEMP.
ELECTRONIC CONTROL
ON/OFF
SWITCH
DISCHARGE
TEMP.
WATER
LEVEL
SENSOR
FUSE
(3A)
TRANSFORMER
LINE
L2
CU1526, CU2026, CU3030
Service Manual
Wiring Diagram, CU1526 and CU2026 50 Hz
THIS UNIT MUST
BE GROUNDED.
DISCHARGE
TEMP.
SENSOR
SUMP TEMP.
SENSOR
ICE
THICKNESS
PROBE
WATER
LEVEL
SENSOR
BN
FAN CYCLING PRESSURE
CONTROL SWITCH
(AIR COOLED ONLY)
R
BK
R
BK
W
W
ELECTRONIC
CONTROL
W
W
J6
DUMP
VALVE
WATER
SOLENOID
J7
1 2
R/W
1
2
J1
3
4
1 2 3
J9
MOT
PUMP
CURTAIN SWITCH
J8
1 2
J10
J2
17-3186-01
4
3
2
1
8
7
6
5
4
3
2
1
BU
CAUTION:
BN
MOT
FAN
W
BN
BN/W
SEE NAMEPLATE FOR
PROPER VOLTAGE REQUIREMENTS
AND MAXIMUM FUSE SIZE
HIGH PRESSURE
CONTROL
(WATER COOLED ONLY)
Y
BK
SOLENOID
HOT GAS
(WHEN 2ND
FAN IS PRESENT)
W
W
L2
T2
Y
BK
W
SOLENOID
HARV ASSIST
T1
POWER SUPPLY
BK
L1
CONTACTOR
FUSE (3A)
BN/W
W/R
W
GN/Y
W/R
PROTECTOR
INTERNAL
PTCR
W/Y
RUN
CAP
O
BK
2
9
W
BK
R
TERMINAL BOX
EARTH GROUND
GN/Y
4
TRANSFORMER
7
COMPRESSOR
GN
5
6
BK
CAUTION: PTCR WILL BE HOT.
COMPRESSOR MAY NOT START IF
PTCR IS NOT ALLOWED TO COOL
USE COPPER CONDUCTORS ONLY
MORE THAN ONE DISCONNECT MEANS MAY BE
REQUIRED TO DISCONNECT ALL POWER TO THIS UNIT.
V
W
W
MOT
FAN
*
May 2008
Page 48
*
(AIR COOLED ONLY)
BK
R3
C1
1 LINE
230V
12V
10 LOAD
S2
Y
O
R
ON/OFF
SWITCH
L1
CONTACTOR T1
WATER
PUMP
DUMP
VALVE
12V
HIGH
PRESSURE
CONTROL
(WC ONLY)
WATER VALVE
HOT GAS VALVE
FAN
MOTOR
FAN
MOTOR
COMPRESSOR
(WHEN APPLICABLE)
(AC ONLY)
RUN
CAP
PTCR
FAN CYCLING
PRESSURE
SWITCH
(A/C ONLY)
CURTAIN
SWITCH 1
CONTACTOR
COIL
HARVEST ASSIST
SOLENOID 1
.33
uF
SWITCH 2
(2 PLATE UNITS ONLY)
ICE
THICKNESS
PROBE
CURTAIN
(AC ONLY)
SUMP
TEMP
ELECTRONIC CONTROL
ON/OFF
SWITCH
DISCHARGE
TEMP
WATER
LEVEL
SENSOR
FUSE
(3A)
TRANSFORMER
LINE
L2
CU1526, CU2026, CU3030
Service Manual
Wiring Diagram, CU3030 50 Hz
CU1526, CU2026, CU3030
Service Manual
Removal and Replacement
Water Reservoir
CU1526 or CU2026
1. Top access and top panel removal is required for this procedure.
2. Shut water supply OFF.
3. Remove left grill.
4. Push and hold the Off button until the unit stops.
5. Push and hold the Clean button until a - appears in the code display. The pump will drain the
reservoir.
6. Disconnect electrical power.
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning removal
procedure.
7. Remove top panel.
8. Remove two screws holding reservoir to evaporator support bracket. Lower sump to drain water.
9. Reach in sump and remove water pump discharge hose.
10. Reach from top, rotate water pump CCW until it is in the release position, then pull the pump up and
out.
11. Pull up on the water pump / float bracket. It is not necessary to remove the bracket, but it must be
raised about an inch to allow the back wall of the reservoir to clear the float shield.
12. Pull water reservoir forward and down into the bin.
Note: The reservoir has tabs that go thru the back panel. You may have to lift up and pull forward to
release them.
May 2008
Page 49
CU1526, CU2026, CU3030
Service Manual
Removal and Replacement
Water Reservoir
CU3030
1. Shut water supply OFF.
2. Remove left grill.
3. Push and hold the Off button until the unit stops.
4. Push and hold the Clean button until a - appears in the code display. The pump will drain the
reservoir.
5. Push two tabs (located left of the pump motor) in until they release from the pump bracket.
6. Push in release ring on water fitting and pull water inlet
tube out.
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning removal
procedure.
7. Disconnect electrical connection from pump motor.
8. Remove discharge hose from pump
9. Lift up on pump bracket to release it from the back wall. Pull forward and out of the machine.
10. Remove one screw holding the reservoir to the evaporator bracket (at the right).
11. Reservoir will drain into storage bin.
12. Push up under back of reservoir and pull forward to release reservoir tabs from back panel.
May 2008
Page 50
CU1526, CU2026, CU3030
Service Manual
Removal and Replacement
Float valve
CU1526 and CU2026
1. Top access and top panel removal will be required for this procedure.
2. Shut water supply Off.
3. Remove two screws and drop the front edge of the reservoir.
4. Disconnect hose from water pump outlet.
5. Disconnect water supply tube at float valve.
6. Lift the right side of the pump bracket up, push to the left and pull the right end of the bracket up so
the mounting pins clear the keyhole slots.
7. Rotate the pump bracket with float 90 degrees so the float is at the back or front.
8. Pull bracket up and out or drop the bracket & float valve down into the storage bin.
9. Remove float valve from pump bracket, replace with new part.
CU3030
1. Top panel removal will aid in this procedure.
2. Remove left grill.
3. Push and hold the Off button until the unit stops or a O appears in the code display.
4. Push and hold the Clean button until a - appears in the code display. The pump will drain the
reservoir.
5. Push in two tabs and release reservoir from pump bracket.
6. Unplug pump from power harness
7. Disconnect pump discharge hose from pump
8. Push release ring to disconnect water supply tube from water inlet fitting.
9. Pull up on pump & bracket until it releases from the back panel.
10. Remove pump, bracket and float valve from unit.
11. Remove float valve from bracket, replace with a new part.
May 2008
Page 51
CU1526, CU2026, CU3030
Service Manual
Removal and Replacement
Water Pump
CU1526 or CU2026
1. Top access and top panel removal is required for this procedure.
2. Disconnect electrical power.
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning removal
procedure.
3. Shut water supply Off.
4. Remove top panel.
5. Remove two screws holding reservoir to evaporator support bracket. Lower sump at front.
6. Reach in sump and remove water pump discharge hose.
7. Reach from top, rotate water pump CCW until it is in the release position, then pull the pump up and
out.
CU3030
1. Disconnect electrical power.
2. Disconnect electrical connection from pump
motor.
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning removal
procedure.
3. Remove discharge hose from pump
4. Rotate water pump CCW until it is in the release position, then pull the pump up and out.
May 2008
Page 52
CU1526, CU2026, CU3030
Service Manual
Removal and Replacement
Purge valve
1. Remove left front grill.
2. Push and hold the Off button to shut the machine off.
3. Disconnect electrical power.
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning removal
procedure.
4. Perform all procedures to remove the ice storage bin.
5. Unplug wires from valve coil.
Note: The coil can be removed from the valve body by rotating it 1/8 turn CW. After removal of the coil
the spring and plunger can be taken out.
6. Remove screws holding valve to mounting bracket.
7. Remove inlet and outlet hoses
8. Remove valve from cabinet.
9. Reverse to reassemble
Water level sensor
1. Switch the machine off.
2. Remove the top panel.
3. Locate water level sensor.
4. Squeeze the locking tabs together and pull the sensor up and out of the sump.
5. Unplug the electrical connection from the sensor.
6. Reverse to reassemble.
May 2008
Page 53
CU1526, CU2026, CU3030
Service Manual
Removal and Replacement
Fan Blade and/ or Motor
1. Disconnect electrical power.
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning removal
procedure.
2. Go thru all steps to remove the ice storage bin.
3. Unplug fan motor from harness.
4. Remove four 3/8" hex head cap screws
securing fan motor brackets to shroud.
5. Remove fan blade. If installing new fan blade,
replace blade at this point and reverse to
reassemble.
Note: Fan blade mounts so it is cupped to blow air
into condenser. See photo.
6. Remove mounting screws securing fan motor
to brackets.
7. Replace fan motor.
Fan Blade or Motor Replacement
8. Attach fan blade to motor.
9. Return brackets to motor.
10. Reattach fan motor assembly to shroud.
11. Reconnect fan motor.
12. Return bin to chassis.
13. Reconnect power, restart unit. Check operation.
May 2008
Page 54
CU1526, CU2026, CU3030
Service Manual
Refrigeration Removal and Replacement Procedures
Thermostatic Expansion Valve
1. Remove left front grill.
2. If the machine was in operation, push and release the Harvest button to shut it down. Wait until the
harvest cycle has ended so the evaporator has no ice on it.
3. Go thru all steps to remove the bin.
4. Disconnect electrical power.
5. Recover refrigerant.
6. Remove insulation covering expansion valve and bulb.
7. Remove strap securing bulb to suction line.
8. Open both discharge and suction access valves
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning removal
procedure.
9. Unsweat the expansion valve from the liquid line. Remove it.
10. Unsweat the drier from the liquid line. Remove it.
11. Connect nitrogen to discharge access valve.
12. Immediately place new valve in ice machine.
13. Open nitrogen bottle and braze expansion valve inlet and outlet joints together. Braze new drier into
system.
14. Shut off nitrogen, shut access valves.
15. Evacuate to at least 300 microns.
16. Weigh in the nameplate charge. Check for leaks.
17. Attach bulb to suction line. Position at 4 or 8 o'clock on the tube. Secure tightly but do not crush the
bulb with the strap.
18. Attach valve and bulb insulation.
19. Reconnect electrical power.
20. Return bin and all panels to their original positions.
May 2008
Page 55
CU1526, CU2026, CU3030
Service Manual
Refrigeration Removal and Replacement Procedures
Compressor
1. Remove left front grill.
2. If the machine was in operation, push and release the Harvest button to shut it down. Wait until the
harvest cycle has ended so the evaporator has no ice on it.
3. Go thru all steps to remove the bin.
4. Open the replacement compressor box. Check the compressor nameplate, be SURE that the
replacement compressor is the correct one for the unit.
5. Disconnect electrical power.
6. Recover refrigerant.
7. Remove compressor terminal cover and disconnect
electrical leads.
8. Remove all the mounting bolts.
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning removal
procedure.
9. Open both discharge and suction access valves
10. Connect nitrogen to discharge access valve.
11. Open nitrogen valve.
12. Unsweat the suction, discharge and process tubes.
13. Unsweat the drier from the liquid line. Remove it.
14. Shut the nitrogen valve.
15. Remove the compressor from the ice machine. Note: Some models may require the control box to
be moved slightly to allow compressor replacement.
16. Immediately place new compressor in ice machine.
17. Open nitrogen bottle and braze compressor suction, discharge and process joints together. Braze
new drier into system.
18. Shut off nitrogen, shut access valves.
19. Evacuate to at least 300 microns.
20. Replace PTCR and run capacitor.
21. Weigh in the nameplate charge. Check for leaks.
22. Reconnect electrical leads.
May 2008
Page 56
CU1526, CU2026, CU3030
Service Manual
Refrigeration Removal and Replacement Procedures
23. Attach compressor terminal cover.
24. Reconnect electrical power.
25. Return bin and all panels to their original positions.
Note: If the compressor is being returned for warranty, braze the stubs shut and tag the compressor with
the required information.
Evaporator
Note: Back and Top access is required for this procedure
1. Remove top panel.
2. Remove access cover on back panel
3. If the machine was in operation, push and release the Harvest button to warm up the evaporator.
4. Disconnect electrical power.
5. Remove harvest assist solenoid
Electrical Shock
Hazard.
Disconnect electrical
power before
beginning removal
procedure.
6. Recover refrigerant.
7. Remove curtain
8. Remove water distributor
9. Release ice thickness sensor
10. Remove water distributor bracket from the top of the evaporator
11. Connect nitrogen bottle to discharge access port. Open both access valves.
12. Open nitrogen valve
13. Unsweat the inlet and outlet refrigerant tubes. Use caution when heating the tubing, do not damage
the freezing compartment walls.
14. Shut nitrogen valve.
15. Remove mounting screws holding the evaporator to the wall. Note: fastener size is 5/16” hex.
16. Remove the evaporator from the ice machine.
17. Attach new evaporator to freezing compartment wall, but do not secure tightly at this time.
May 2008
Page 57
CU1526, CU2026, CU3030
Service Manual
Refrigeration Removal and Replacement Procedures
18. Install the harvest assist solenoid. Note location of ejector pin. Adjust position of the evaporator
slightly to center the pin in the guide hole of the evaporator. When centered, tighten all evaporator
fasteners.
19. Open nitrogen valve
20. Reconnect inlet and outlet tubes by brazing the copper tubes together.
21. Replace filter drier.
22. Shut access valves, remove nitrogen bottle.
23. Evacuate to at least 300 microns.
24. Weigh in the nameplate charge. Check for leaks.
25. Return ice thickness sensor bracket, ice thickness sensor, water distributor, curtain and evaporator
cover to their original positions.
26. Reconnect electrical power.
27. Return all panels to their original positions.
May 2008
Page 58
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