Stoelting U412 Operators Manual

Model U412 Series

SERVICE MANUAL

Manual No. 513630 Rev.2

This manual provides basic information about the machine. Instructions and suggestions are
given covering its operation and care.

The illustrations and specifi cations are not binding in detail. We reserve the right to make
changes to the machine without notice, and without incurring any obligation to modify or pro­vide new parts for machines built prior to date of change.

DO NOT ATTEMPT to operate the machine until instructions and safety precautions in this
manual are read completely and are thoroughly understood. If problems develop or questions
arise in connection with installation, operation, or servicing of the machine, contact Stoelting.

stoeltingfoodservice.com

Stoelting Foodservice Equipment
502 Highway 67
Kiel, WI 53042-1600
U.S.A.

Main Tel: [phone]
Fax: [phone]

Customer Service: 888.429.5920
Fax: [phone]
Email: [e-mail]

© 2014 PW Stoelting, LLC

A Few Words About Safety

Safety Information

Read and understand the entire manual before
operating or maintaining Stoelting equipment.

This manual provides the operator with information
for the safe operation and maintenance of Stoelting
equipment. As with any machine, there are hazards
associated with their operation. For this reason safety
is emphasized throughout the manual. To highlight
specifi c safety information, the following safety defi ni-
tions are provided to assist the reader.

The purpose of safety symbols is to attract your at­tention to possible dangers. The safety symbols, and
their explanations, deserve your careful attention
and understanding. The safety warnings do not by
themselves eliminate any danger. The instructions
or warnings they give are not substitutes for proper
accident prevention measures.

If you need to replace a part, use genuine Stoelting
parts with the correct part number or an equivalent
part. We strongly recommend that you do not use
replacement parts of inferior quality.

Safety Alert Symbol:

This symbol Indicates danger, warning or caution.

Attention is required in order to avoid serious per­sonal injury. The message that follows the symbol
contains important information about safety.

Signal Word:

Signal words are distinctive words used throughout

this manual that alert the reader to the existence and
relative degree of a hazard.

WARNING

The signal word “WARNING” indicates a potentially
hazardous situation, which, if not avoided, may result
in death or serious injury and equipment/property
damage.

CAUTION

The signal word “CAUTION” indicates a potentially

hazardous situation, which, if not avoided, may result
in minor or moderate injury and equipment/property
damage.

CAUTION

The signal word “CAUTION” not preceded by the
safety alert symbol indicates a potentially hazardous
situation, which, if not avoided, may result in equip­ment/property damage.

NOTE (or NOTICE)

The signal word “NOTICE” indicates information or
procedures that relate directly or indirectly to the
safety of personnel or equipment/property.

TABLE OF

CONTENTS

Section Description Page
1 Description and Specifi cations

1.1 Description .................................................................................................. 1

1.2 Specifi cations ............................................................................................. 2

1.3 Modes of Normal Operation .......................................................................3

1.4 Mix Level Indicators .................................................................................... 5

1.5 Storage Refrigeration .................................................................................5

1.6 Operation During Sensor Failure ................................................................ 5

1.7 Motor Profi le Cutout Compensation ........................................................... 5

2 Installation Instructions

2.1 Safety Precautions .....................................................................................7

2.2 Shipment and Transit ..................................................................................7

2.3 Machine Installation .................................................................................... 7

2.4 Installing Permanent Wiring ........................................................................ 7

2.5 Mix Pump .................................................................................................... 8

A. Mix Pump Hose Installation..................................................................................8

B. Mix Pickup Hose Installation ................................................................................8

C. Mix Low Level Indicator Adjustment ..................................................................... 10

3 Initial Set-Up and Operation

3.1 Operator’s Safety Precautions ................................................................... 11

3.2 Operating Controls and Indicators .............................................................. 11

3.3 Disassembly of Machine Parts ................................................................... 13

A. Disassembly of Blender and Front Door ..............................................................13

B. Disassembly of Auger ..........................................................................................13

3.4 Cleaning Disassembled Parts ....................................................................13

3.5 Sanitizing Machine Parts ............................................................................14

3.6 Cleaning the Machine ................................................................................. 14

3.7 Assembling Machine ..................................................................................14

3.8 Sanitizing .................................................................................................... 15

3.9 Initial Freeze Down and Operation .............................................................16

A. Adding Mix ........................................................................................................... 16

B. Preparing the IntelliTec Control ............................................................................16

C. Initial Freeze Down ..............................................................................................17

D. Adjusting the IntelliTec Control ............................................................................. 17

E. Serving Product....................................................................................................17

3.10 Normal Freeze Down and Operation .......................................................... 17

3.11 Mix Information ...........................................................................................18

3.12 Operation of Mix Pump ............................................................................... 18

3.13 Mix Pump Cleaning ....................................................................................19

3.14 Disassembly and Inspection of Removable Parts ...................................... 19

Section Description Page
4 Maintenance and Adjustments

4.1 Freezer Adjustment .................................................................................... 21

4.2 Product Consistency Adjustment ................................................................ 21

4.3 Locking the Control Panel ..........................................................................21

4.4 Obtaining Readings and Modifying Settings (Service Personnel Only) ...... 21

4.5 Readings (Service Personnel Only) ...........................................................22

4.6 Adjustments (Service Personnel Only) ....................................................... 23

4.7 Other Settings (Service Personnel Only) .................................................... 23

4.8 Overrun Adjustment .................................................................................... 24

4.9 Mix Pump Hose Reposition ........................................................................ 25

4.10 Mix Pump Hose Replacement ....................................................................25

4.11 Cab Temperature Adjustment ..................................................................... 26

4.12 Drive Belt Tension Adjustment .................................................................... 26

4.13 Condenser Cleaning (Air-Cooled Freezers) ............................................... 27

4.14 Preventative Maintenance .......................................................................... 27

4.15 Extended Storage ....................................................................................... 27

5 Refrigeration System

5.1 Refrigeration System .................................................................................. 29

5.2 Refrigerant Recovery and Evacuation ........................................................ 29

5.3 Refrigerant Charging .................................................................................. 30

5.4 Compressor ................................................................................................ 31

5.5 Condenser .................................................................................................. 32

5.6 Evaporator .................................................................................................. 32

5.7 Valves ......................................................................................................... 32

A. Thermostatic Expansion Valve (TXV) ..................................................................32

B. Check Valve ......................................................................................................... 33

C. High Pressure Cutout ........................................................................................... 33

D. Hot Gas Bypass ...................................................................................................34

E. Evaporator Pressure Regulator (EPR) ................................................................. 35

F. Water Valve (Water Cooled Models Only) ............................................................ 35

5.8 Solenoid ...................................................................................................... 36

5.9 Filter Drier ................................................................................................... 37

5.10 Capillary Tube .............................................................................................38

5.11 Cab Unit ......................................................................................................38

Section Description Page
6 Electrical and Mechanical Control Systems

6.1 IntelliTec Controller ..................................................................................... 39

6.2 Contactors .................................................................................................. 39

6.3 Drive Motor ................................................................................................. 40

6.4 Capacitors ..................................................................................................40

6.5 Gearbox ...................................................................................................... 41

6.6 Condenser Fan Motor (Air-Cooled Only) .................................................... 42

6.7 Cab Condenser Fan Motor .........................................................................42

6.8 Switches ..................................................................................................... 43

A. Spigot Switch ....................................................................................................... 43

B. Blender Activation Switch .....................................................................................44

C. Pump Pressure Switch ......................................................................................... 44

6.9 Potential Relay ...........................................................................................45

6.10 Temperature Control Sensor ......................................................................45

6.11 Spinner Speed Control Harness ................................................................. 45

7 Troubleshooting

7.1 Error Codes ................................................................................................ 47

7.2 Troubleshooting - Error Codes ................................................................... 47

7.3 Troubleshooting - Machine .........................................................................50

7.4 Troubleshooting - Mix Pump ....................................................................... 51

8 Replacement Parts

8.1 Auger Shaft and Front Door Parts ..............................................................53

8.2 Blender Parts and Trays ............................................................................. 54

8.3 Cab Tubing Assembly ................................................................................. 55

8.4 Spigot Cam Assembly ................................................................................ 56

8.5 Front Panel ................................................................................................. 57

8.6 Part Kits ...................................................................................................... 57

8.7 Pump Parts ................................................................................................. 58

8.8 Cab Interior ................................................................................................. 60

8.9 Header Panel - Electrical ............................................................................ 61

8.10 Left Hand Side ............................................................................................ 62

8.11 Right Hand Side .........................................................................................63

8.12 Rear ............................................................................................................ 64

8.13 Brushes, Decals and Lubrication ................................................................ 65

8.14 Stainless Steel Panels ................................................................................ 65

8.15 Refrigeration Diagram and Wiring Diagram ................................................ 66

SECTION 1

DESCRIPTION AND SPECIFICATIONS

1.1 DESCRIPTION

The U412 is an ultra high capacity fl oor model shake
machine. It is equipped with fully automatic controls to
provide a uniform product. This manual is designed to
assist qualifi ed service personnel and operators with instal-
lation, operation and maintenance of the U412 machine.

Figure 1-1 Model SU412 Machine

Figure 1-2 Machine Dimensions

1

1.2 SPECIFICATIONS

Dimensions Machine with crate

width 19-1/8’’ (48,6 cm) 27’’ (68,6 cm)

height 67’’ (170,2 cm) 78’’ (198,1 cm)

depth 38-3/4’’ (98,4 cm) 48’’ (121,9 cm)

Weight 450 lbs (204,1 kg) 650 lbs (294,8 kg)

Electrical 1 Phase, 208-240 VAC, 60Hz

circuit ampacity

overcurrent protection

device

Compressor 11,000 Btu/hr Scroll™ Compressor

Drive Motor 3/4 hp

Air Flow Air cooled units require 3” (7,6 cm) air space on both sides, 6” back.

Plumbing Fittings

Hopper Volume 8 gallons (30,29 liters)

Freezing Cylinder

Volume

Model SU412

19A minimum

30A maximum

Water cooled units require 1/2” N.P.T. water and drain fi ttings. Maximum water

pressure of 130 psi. Minimum water fl ow rate of 3 GPM. Ideal EWT of 50°-70°F

2.1 gallon (7,95 liters)

Production Capacity 30 GPH (113,56 liters)

SU412

Refrigerant R-404A

Charge 32 oz

Suction Pressure

(at 72°F)

Discharge Pressure 210-235 psig

Cab Pressure

(only cab running)

EPR Valve 78-80 psig

18 psig (maintained by the bypass valve)

25-27 psig

Advanced On Time 28 seconds

* CutOut amps must be set on site.

Menu Display Value

Basic CutOut * amps

Cut In T 26.5 °F

Cycles 20 count
Stir On 15 seconds
Stir Off 300 seconds

Off Time 450 seconds

Stb Time 120 minutes

Sl1DrvOn 120 seconds

Sl1DrOff 180 seconds
Sl2CutIn 37 °F
Sl2CtOut 31 °F
DftOffTm 900 seconds

Storage Refriger 3 Cabinet

CabCutIn 38 °F
CabCtOut 34 °F

Cab Off 13 minutes
Cab On 130 seconds

U412 Confi gurations

Model Spinner Speed

U412 Standard -
TU412 Extra Thick -
SU412 Standard with Spinner 1600 rpm

STU412 Extra Thick with Spinner 2400 rpm

2

1.3 MODES OF NORMAL OPERATION

Following are details of the operational modes on the U412.

NOTE:

The preset amounts, times, and temperatures
listed below are references to actual settings on
the IntelliTec control. Refer to Table 1-1 on page 6
for details on each setting.

A. INITIAL STATUS

When the Main Freezer Power and Freezing Cylinder
switches are placed in the ON position, the machine will
start in the “Sleep 1 Mode”. The display will read “Sleep
1 Mode”. The control will eventually move into the “Sleep
2” mode if the PUSH TO FREEZE button is not pressed.
When the PUSH TO FREEZE button is pressed the control
will move to the “Serve Mode”.

B. SERVE MODE

When the PUSH TO FREEZE button is pressed or a spigot
handle is pulled, the “Serve Mode” begins. The drive motor
starts, and after a 3 second delay, the compressor starts.
The display reads “FREEZING” on the top line and a bar
on the bottom line increases with product consistency.
A toroid on the IntelliTec control senses increasing drive
motor amperage as the product comes to consistency in
the freezing cylinder. When the control senses the product
is at 75% of consistency, the display will read “SERVE”,
the amber LED will go out and the green LED will blink.
At this time, product can be served from the machine.
The drive motor and compressor will continue to run until
the toroid reads a preset value (CutOut amps). When
the toroid reads the CutOut amps on the drive motor, the
compressor turns off. After a 3 second delay, the drive
motor turns off. The product in the freezing cylinder is now
at serving temperature and consistency and the green
LED will remain lit.

After product is at consistency, the IntelliTec control
continuously monitors refrigerant temperature through a
thermistor mounted on the side of the freezing cylinder.
When the temperature increases to a preset amount (Cut
In T), a 3-second drive motor pre-stir analyzes product
consistency. The pre-stir check is also performed each
time the spigot handle is opened. This check prevents
over-freezing of product, especially during frequent, small
volume draws. If product requires a freezing cycle, the
control will start the cycle.

During the “Serve Mode”, a stir cycle starts. This cycle is
independent of the freezing cycle and is based on preset
times (Stir On and Stir Off). The stir cycle prevents product
separation. If a freezing cycle is initiated, the timer is reset.

In addition to the “Serve Mode” freezing cycle, there is a
freezing cycle based on a preset time (DftOffTime). If this
time is attained without a freezing cycle, the control will
automatically start a freezing cycle. If a freezing cycle is
initiated, the timer is reset.

Figure 1-3 Serve Mode

The machine will remain in “Serve Mode” until the cycle
count setting is attained. The cycle count is the number
of active freezing cycles and is based on a preset value
(Cycles). Once the cycle count has been reached without
user interruption, the control will move into the “Standby
Mode”.

If the PUSH TO FREEZE button is pressed or a spigot
handle is pulled, the cycle count is reset and the control
will move to the beginning of the “Serve Mode”. Refer to
Figure 1-3 for a graphical representation of the “Serve
Mode”.

C. STANDBY MODE

If product has not been drawn from the spigot and the
preset number of active freezing cycles is met, the control
moves into the “Standby Mode”. In “Standby Mode”, the
freezing cycle is based on preset timers (On Time and Off
Time), and prevents ice crystals from building up in the
product. Because the product remains partially frozen,
it can quickly return to servable consistency when the
PUSH TO FREEZE button is pressed.

During “Standby Mode”, the stir cycle runs. This cycle is
based on preset, timed intervals (Stir On and Stir Off) and
prevents product separation.

Figure 1-4 Standby Mode

3

The “Standby Mode” maintains product quality during
slow times, while minimizing reactivation time. This mode
lasts for a preset time (Stb Time). Once this time has been
reached without user interruption, the control moves into
the “Sleep 1 Mode”. Refer to Figure 1-4 for a graphical
representation of the “Standby Mode”.

If a spigot is opened or the PUSH TO FREEZE button is
pressed, the control will move to “Serve Mode”. Product
in the front of the freezing cylinders may or may not be at
consistency. The state of the product is dependent on a
number of variables but will come to consistency quickly.

D. SLEEP 1 MODE

After the “Standby Mode” time has expired without user
interruption, the control will move into the “Sleep 1 Mode”.
During the “Sleep 1 Mode”, the stir cycle is handled by
preset timers (Sl1DrvOn and Sl1DrOff), and allows product
to melt to a liquid state by using agitation cycles without
any fl ow of refrigerant. Although the product temperature
never increases above 41°F, the product thaws rapidly
which minimizes product breakdown. The control will stay
in the “Sleep 1 Mode” until sensing a preset temperature
(Sl2CutIn). When this temperature has been reached with­out user interruption, the control will move to the “Sleep 2
Mode”. Refer to Figure 1-5 for a graphical representation
of the “Sleep 1 Mode”.

Figure 1-5 Sleep 1 Mode

If a spigot is opened or the PUSH TO FREEZE button is
pressed, the control will move to “Serve Mode”. If the spigot
is opened in “Sleep 1 Mode”, the product will not be at
consistency. The operator must wait until the fi rst “Serve
Mode” freezing cycle has completed to serve product.

E. SLEEP 2 MODE

The “Sleep 2 Mode” maintains the freezing cylinder
temperature between two preset values (Sl2CutIn and
Sl2CtOut). During the “Sleep 2 Mode”, the stir cycle
runs. This cycle is based on preset, timed intervals (Stir
On and Stir Off) and prevents product separation. The
“Sleep 2 Mode” is often referred to by customers as the
“night mode” and the machine will stay in this mode until
a spigot is opened or the PUSH TO FREEZE button is

Figure 1-6 Sleep 2 Mode

pressed. When this occurs, the control will move to “Serve
Mode”. If the spigot is opened at this time, the product
will be liquid. The operator must wait until the fi rst “Serve
Mode” freezing cycle has completed to serve product.
Refer to Figure 1-6 for a graphical representation of the
“Sleep 2 Mode”.

F. INTELLITEC RESTART

If a hard error occurs (refer the hard error list below), the
IntelliTec control will wait 5 minutes then attempt to clear
the error by restarting itself. The control will count each
restart attempt. The restart count will reset if the PUSH
TO FREEZE button is pressed, the spigot is pulled, or
the Freezing Cylinder OFF/ON switch is placed in the
OFF position.

The following are considered hard errors:

ERROR CODE MALFUNCTION

2 High Torque

3 Run Time

4 Clean

7 Drive Motor

9 High Pressure Cutout

When a restart occurs, the second line of the display will
read “Restart” and the backlight will blink. This will occur
regardless of the system mode.

G. SLEEP 3 MODE

If a high torque, run time, or drive motor error condition
occurs on the third restart attempt, the control will move
to the “Sleep 3 Mode”.

In “Sleep 3 Mode” freezing cylinder refrigeration will run
for 4 seconds every 10 minutes. This ensures the product
temperature never increases above 40°F. The stir cycle
and the auger do not run during “Sleep 3 Mode”.

The control will exit “Sleep 3 Mode” if the PUSH TO
FREEZE button is pressed, the spigot is pulled, or the
Freezing Cylinder OFF/ON switch is placed in the OFF
position.

4

H. CLEAN MODE

When the CLEAN button is pressed, freezing cylinder
refrigeration stops, the drive motor starts and will run for
20 minutes and a 5 minute countdown timer is displayed.
After the time has elapsed, an optional audible alarm will
sound if this accessory has been installed. The audible
alarm is a reminder for the operator to end the “Clean
Mode” when cleaning is completed.

If the machine is kept in “Clean Mode” for more than 20
minutes, the auger drive motor stops, and an error code
(E4) is displayed on the display panel. The error code
prevents damage to the machine that could occur during
an extended clean mode (Refer to Section 8 - Trouble­shooting for details). To clear this error, place the Freez­ing Cylinder Off-On switch in the Off position and back
in the On position. If the machine is still being cleaned,
pushing the CLEAN button will reset the timer and restart
the “Clean Mode”.

1.4 MIX LEVEL INDICATORS

The cabinet is equipped with a capacitive sensor to moni­tor mix level. When the mix level drops below the sensor
limit, the lower line of the display will read “Low Mix” and
the display will fl ash. To clear the “Low Mix” error, add
mix to the cabinet’s mix container.

1.5 STORAGE REFRIGERATION

The IntelliTec control is programmed to handle refrigeration
of the cabinet independently from the freezing cylinder.
The control maintains cabinet temperature between two
preset values (CabCutIn and CabCtOut). The cabinet
will operate automatically unless one of the following
conditions are met:

If the Main Power switch is in the OFF position

the Cab Off light on the front of the machine will
fl ash.

If the cabinet door is opened during a refrigeration

cycle, the evaporator fan will continue to run but
the refrigeration cycle will be interrupted to prevent
the evaporator coils from icing up.

If there is a High Pressure Cutout Error (E9) all

the refrigeration stops.

NOTE

If the temperature in the cabinet stays above 50°F
for more than two hours, the machine will go into
Sleep Mode and a clean message will be shown
on the display.

1.6 OPERATION DURING SENSOR FAILURE

The IntelliTec control is designed to allow the machine to
continue to function if a temperature sensor failure oc­curs. If a sensor fails, the display will show the error and
the control will run the machine on timers for the freezing
cycle or cabinet refrigeration. This allows the operator to
continue to serve product from the machine until proper
servicing can be completed.

Figure 1-7 Serve Mode (Sensor Failure)

A. SERVE AND STANDBY MODE

In the event of a temperature sensor failure on a freezing
cylinder, the IntelliTec control will function in two modes,
“Serve Mode” and “Standby Mode”. When the product is
at consistency in “Serve Mode”, the IntelliTec control uses
a timer instead of the sensor and will not start another
freezing cycle until a preset value (DftOffTm) is met.

The control will monitor product after it is at consistency,
activating the stir cycle and counting the number of cycles.
When the cycle count is reached, the control will move
to “Standby Mode”.

The “Standby Mode” is the same as in normal operation
with the exception of when the preset time (Stb Time) is
met, the control moves back into the “Serve Mode”. Refer
to Figure 1-7 for details.

B. CABINET REFRIGERATION

In the event of a temperature sensor failure in the cabi­net, the cabinet refrigeration cycle is managed by preset
times (Cab On and Cab Off). This refrigeration cycle is
independent of the freezing cylinder refrigeration and the
cycle restarts if the cabinet door is opened.

1.7 MOTOR PROFILE CUTOUT
COMPENSATION

The IntelliTec control is programmed to automatically
function at a range of supply voltages. This feature pro­vides the advantage of having product maintained at a
specifi c temperature and consistency irrespective of the
supply voltage. A motor profi le curve is programmed on
the IntelliTec control and provides a relationship between
the supply voltage and drive motor cutout amperage. De­pending on the supply voltage, the control varies cutout
amperage according to the motor profi le. This feature is
automatic and does not need any confi guring.

5

IntellITec Control Setting Specifi cations

Basic Menu DISPLAY Value MODE DEFINITION

CutOut * Serve Amp draw setting for cut out

Cut In T 26.5°F Serve Temperature setting for cut in

Cycles 20 Serve Freezing cycles before going into Standby Mode

Stir On 15 sec Serve Stir-only on time

Stir Off 300 sec Serve Stir-only off time

Advanced Menu DISPLAY Value MODE DEFINITION

On Time 28 sec Standby Freezing cycle “on” time (runs on timers only)

Off Time 450 sec Standby Freezing cycle “off” time

Stb Time 120 sec Standby Total time in mode

Sl1DrvOn 120 sec Sleep 1 Drive motor “on” timer

Sl1DrOff 180 sec Sleep 1 Drive motor “off” timer

Sl2CutIn 37°F Sleep 2 Cut in temperature

Sl2CtOut 31°F Sleep 2 Cut out temperature

DftOffTm 900 sec No Sensor Default “off” time. Used in case of sensor failure

Storage Menu DISPLAY Value MODE DEFINITION

Refriger Cabinet All Set to None, 1 Hopper, 2 Hopper, or Cabinet

CabCutIn 38°F All Refrigerated cab cut in temperature

CabCtOut 34°F All Refrigerated cab cut out temperature

Cab Off 13 sec No Sensor Default “off” time. Used in case of sensor failure

Cab On 130 sec No Sensor Default “on” time. Used in case of sensor failure

* The CutOut value needs to be adjusted to product requirements. Refer to the 2183775 - Specifi cation Sheet for SU412
Control located in the plastic pouch behind the header panel.

Table 1-1 IntelliTec Control Setting Specifi cations

6

SECTION 2

INSTALLATION INSTRUCTIONS

2.1 SAFETY PRECAUTIONS

Do not attempt to operate the machine until the safety
precautions and operating instructions in this manual are
read completely and are thoroughly understood.

Take notice of all warning labels on the machine. The la­bels have been put there to help maintain a safe working
environment. The labels have been designed to withstand
washing and cleaning. All labels must remain legible for
the life of the machine. Labels should be checked periodi­cally to be sure they can be recognized as warning labels.

If danger, warning or caution labels are needed, indicate
the part number, type of label, location of label, and quantity
required along with your address and mail to:

STOELTING, INC.

ATTENTION: Customer Service

502 Hwy. 67

Kiel, Wisconsin 53042

2.2 SHIPMENT AND TRANSIT

The machine has been assembled, operated and inspected
at the factory. Upon arrival at the fi nal destination, the
entire machine must be checked for any damage which
may have occurred during transit.

With the method of packaging used, the machine should
arrive in excellent condition. THE CARRIER IS RESPON­SIBLE FOR ALL DAMAGE IN TRANSIT, WHETHER
VISIBLE OR CONCEALED. Do not pay the freight bill
until the machine has been checked for damage. Have
the carrier note any visible damage on the freight bill. If
concealed damage and/or shortage is found later, advise
the carrier within 10 days and request inspection. The
customer must place a claim for damages and/or short­ages in shipment with the carrier. Stoelting, Inc. cannot
make any claims against the carrier.

2.3 MACHINE INSTALLATION

WARNING

Installation must be completed by a qualifi ed
electrician/refrigeration specialist.

Incorrect installation may cause personal injury,
severe damage to the machine and will void fac­tory warranty.

A. Uncrate the machine.

B. Install the four casters. Turn the threaded end

into the machine until no threads are showing. To
level, turn out casters no more than 1/4” maximum,
then tighten all jam nuts.

C. The machine must be placed in a solid level

position.

NOTE

Accurate leveling is necessary for correct drainage
of freezing cylinder and to insure correct overrun.

D. Machines with air cooled condensers require a

minimum of 3” (7,5cm) of space on all sides and
10” (25cm) at the top for proper circulation. (Fig.
2-1)

Figure 2-1 Space and Ventilation Requirements

E. Machines that have a water cooled condenser

require 1/2” NPT supply and drain fi ttings.

2.4 INSTALLING PERMANENT WIRING

To install wiring follow the steps below:

A. Refer to the nameplate on the side panel of the

machine for specifi c electrical requirements. Make
sure the power source in the building matches
the nameplate requirements.

B. Remove the back panel and the junction box

cover located at the bottom of the machine.

C. Install permanent wiring according to local code.

Installation of the machine involves moving the machine
close to its permanent location, removing all crating, set­ting in place, assembling parts, and cleaning.

7

6” (15cm)

Figure 2-2 Mix Hose Installation

2.5 MIX PUMP

A. MIX PUMP HOSE INSTALLATION

Follow the steps below to install the mix pump hose in
the cabinet part of the machine.

1. Turn the mix pump on. The switch is located at
the top of the cabinet.

2. Feed one end of the mix pump hose into the
entering or pickup hose side (left) of black cover
(Fig 2-2).

NOTE

Feed the tube into the clamp so the natural curve of
the tube is towards the outside of the black cover.
This prevents the hose from looping around the
black cover twice.

3. Gently push the hose into the black cover until it
begins to feed.

4. Allow the hose to feed itself through the pump
until about 6” (15cm) remains on the entering
side.

5. Turn the pump off.

6. Connect the mix pump hose to the elbow fi tting
(located on the left side of the mix line manifold)
using a small hose clamp. Be careful not to twist
the mix hose.

7. Turn the pump on.

8. Allow the remaining 6” (15cm) of tubing to feed
through pump until the hose adapter prevents
further feeding.

9. Turn the pump off.

CAUTION

Risk of Product Damage

Air/Mix Tee must remain below the black cover
clamp. If the Tee is above the pump, mix may drain
into the air compressor resulting in pump damage.

10. Connect the free end of the mix pump hose to
the 3-way Tee (Fig. 2-3). When all connections
are complete, the 3-way Tee must be lower than
the black pump housing.

B. MIX PICKUP HOSE INSTALLATION

The U412 machine may be connected to the standard mix
container or up to three prepacked mix bags. Follow the
instructions below that match your confi guration.

Standard Connection:

1. Connect a 2” (5cm) length of 3/8” (9,5mm) ID
plastic food grade tubing to the mix pickup
assembly. Secure with hose clamps. Place the
assembly through the hole in the cover and install
the retaining clip.

8

Figure 2-3 Mix Pump Connections for Standard Mix Container

2. Connect the free end of the tubing to the mix check
valve. Observe the direction of the check valve
fl ow arrow. Secure with a hose clamp. Connect a
24” (61cm) length of 3/8” (9,5mm) ID plastic food
grade tubing to the free end of the check valve
and secure with a hose clamp.

3. Connect the elbow fi tting to the free end of the
tubing. Connect the opposite end of the elbow
to 1/4” ID tan tubing on the left side of the pump
head. Secure with hose clamps (Fig. 2-3).

When Using Bag Connection System (BCS) with Three
Bags (optional kit):

The position of the three bags in the mix container is
important. The bag that is connected nearest the outlet
of the manifold will drain last and should be placed at
the back of the mix container. The mix low level indicator
relies on proper bag placement.

1. Connect 3/8” (9,5mm) ID plastic food grade tubing
to a bag adapter. Secure with hose clamps.

2. Slide the hose clip over free end of 3/8” (9,5mm)
ID plastic food grade tubing. Attach the free end
of the tubing to a manifold adapter. Secure with
a large hose clamp or equivalent.

3. Push the manifold adapter with spring and valve
into the left port (nearest the manifold outlet) of
the mix inlet manifold and secure with a retaining
clip. (Fig. 2-5).

Mix Outlet

Drains

Last

Figure 2-4 BCS Mix Inlet Manifold

9

4. Repeat steps 1 to 3 for the middle port and for
the right port of the mix inlet manifold.

5. Place three mix bags into the mix container.

6. Connect the bag adapter attached to the left side
of the manifold (closest to the mix outlet) to the
mix bag in the back of the mix container.

7. Connect the bag adapter attached to the middle
of the manifold to the mix bag in the middle of
the mix container.

8. Connect the bag adapter attached to the right
side of the manifold (farthest from the mix outlet)
to the mix bag in the front of the mix container.

When Using Bag Connection System (BCS) with One
or Two Bags (optional kit):

When connecting one or two bags, the manifold adapt­ers must be installed closest to the manifold outlet and
the manifold plug(s) must be placed farthest from the
manifold outlet.

1. Connect 3/8” (9,5mm) ID
plastic food grade tubing
to a bag adapter. Secure
with hose clamps.

2. Slide the hose clip
over the free end of
the tubing. Attach the
free end of the tubing
to a manifold adapter.
Secure with a large hose
clamp.

3. Push the manifold
adapter with spring and
valve into the left port
(nearest the manifold
outlet) of the mix inlet
manifold and secure
with retaining clip. (See
Figure 2-5).

4. If using two mix bags,
repeat steps 1 to 3 for
the middle port.

5. Install a manifold plug
into each empty inlet and
secure with a retaining
clip.

6. Place the mix bag(s) into
the mix container.

7. Connect the bag adapter
attached to the left side
of the manifold (closest
to the mix outlet) to the
mix bag in the back of
the mix container.

Manifold

Adapter

C. MIX LOW LEVEL INDICATOR ADJUSTMENT

The sensitivity of the “Mix Low” indication that displays on
the control panel can be adjusted to operator preference.
If more advanced notice of low mix is required, loosen the
black adjustment knobs located on the sensor brackets
at the back of the machine cabinet and slide the bracket
upwards. If the “Mix Low” message appears while there
is still suffi cient mix in the container, slide the bracket
downward. Be sure to tighten the adjustment knobs after
properly positioning the sensor.

Mix Inlet

Retaining

Clip

Manifold

Plug

Bag Adapter

Manifold

Figure 2-5 Bag Connection System (Optional)

10

SECTION 3

INITIAL SET-UP AND OPERATION

3.1 OPERATOR’S SAFETY PRECAUTIONS

SAFE OPERATION IS NO ACCIDENT; observe these
rules:

A. Know the machine. Read and understand the

Operating Instructions.

B. Notice all warning labels on the machine.

C. Wear proper clothing. Avoid loose fi tting garments,

and remove watches, rings or jewelry that could
cause a serious accident.

D. Maintain a clean work area. Avoid accidents by

cleaning up the area and keeping it clean.

E. Stay alert at all times. Know which switch, push

button or control you are about to use and what
effect it is going to have.

F. Disconnect power for maintenance. Never

attempt to repair or perform maintenance on the
machine until the main electrical power has been
disconnected.

G. Do not operate under unsafe operating conditions.

Never operate the machine if unusual or excessive
noise or vibration occurs.

3.2 OPERATING CONTROLS AND INDICATORS

Before operating the machine, it is required that the op­erator know the function of each operating control. Refer
to Figure 3-1 for the location of the operating controls on
the machine. For the information regarding error codes
displayed on the control panel, refer to the troubleshooting
section of this manual.

A. MAIN FREEZER POWER SWITCH

The Main Freezer Power switch is a two position rocker
switch that supplies power to the IntelliTec control, freez­ing cylinder circuits lower cabinet refrigeration system.
When the switch is placed in the ON position, the cabinet
refrigeration system will run until the preset temperature
is reached; then it will cycle ON and OFF to maintain that
temperature. Power to the freezing cylinders can then be
controlled with the Freezing Cylinder OFF/ON switch.

B. FREEZING CYLINDER OFF/ON SWITCH

The Freezing Cylinder OFF/ON switch is a two position
toggle switch used to supply power to the freezing cylinder
control circuit. When the switch is in the OFF position,
the freezing cylinder’s refrigeration system and auger will
not operate. When the switch is in the ON position, the
machine will be operational.

Main Freezer

Power Off/On

Cab Off

Indicator Light

Blender Power Off/

On Circuit Breaker

Freezing
Cylinder

Off/On

IntelliTec Control

(See Figure 3-2)

Pump

Off/On

Figure 3-1 Machine Controls

11

C. SPIGOT SWITCH

The spigot switch is mounted to the spigot cam assembly
behind the header panel. When the spigot is opened to
dispense product, the spigot switch opens and the “Serve
Mode” begins.

D. BLENDER POWER OFF/ON AND CIRCUIT BREAKER

SWITCH

The Blender Power Off/On and Circuit Breaker switch
is a two position toggle switch used to supply power to
the blender (SU412 models). When the switch is in the
OFF position, there is no power to the blender. When the
switch is in the ON position, the blender will operate any
time the spigot handle is pushed to the right. This switch
also serves as a circuit breaker to interrupt power if the
rotation of the blender agitator becomes hindered.

E. CAB OFF INDICATOR LIGHT

A fl ashing light indicates the Main Freezer Power Switch
is in the OFF position; no refrigeration is being supplied
to the cab. Place the Main Freezer Power switch in the
ON position for cab refrigeration.

F. PUMP SWITCH

The pump motor switch is the toggle switch located on
the front of the machine. When the switch is placed in
the OFF position, the pump will not run. When the switch
is placed in the ON position, the pump will run until the
preset pressure is reached. It then cycles on and off as
product is drawn to maintain that pressure.

G. PUSH TO FREEZE BUTTON

The PUSH TO FREEZE button is a membrane or snap
switch used to initiate “Serve Mode”.

NOTE

After the PUSH TO FREEZE button is pressed,
the drive motor starts. After a 3-second delay, the
compressor will start.

H. LEDS

The membrane switch (touchpad) features two lights: a
green LED and an amber LED. The green LED is lit dur­ing “Serve Mode”. During freeze down, it is not lit. When
product consistency approaches 90% in the freezing
cylinder, the green LED fl ashes. The amber LED is on
during all other modes. Both LEDs alternatively fl ash if
an error occurs or if the freezing cylinder is off.

I. CLEAN BUTTON

The CLEAN button is a membrane, or snap switch. When
the button is pressed, the freezing cycle stops and the
drive motor will start. A CLEAN message will display on
the LCD screen along with a 5-minute countdown timer.
If the button is pressed again, the timer will reset. To
exit the CLEAN mode, turn the Freezing Cylinder OFF/
ON switch to the OFF position. If the machine is left in
CLEAN for more than 20 minutes, an error code (E4) will
be displayed on the display panel. Place the Freezing
Cylinder OFF/ON switch in the OFF position and back in
the ON position to clear this error.

J. DRIVE MOTOR OVERLOAD

The internal drive motor overload will trip if the drive
motor is overloaded. It will reset after approximately 10­12 minutes. If the drive motor continues to trip, refer to
Troubleshooting in Section 5.

K. MIX LOW LIGHT INDICATOR

A MIX LOW message will appear on the LCD display to
alert the operator of a low mix condition. The message
will display when there is approximately one gallon of
mix left in the mix container or when one bag of the Bag
Connection System (BCS) is empty. When the MIX LOW
message is displayed, refi ll the container or replace a
bag immediately.

L. MENU NAVIGATION BUTTONS

The Menu Navigation Buttons allow the user to display
information regarding the machine’s status of operation
as well as adjust product consistency (Fig. 3-2).

Selection Button (SEL) The SEL button is used in

combination with the left arrow button to enter into
the settings of the IntelliTec control. This button is
also used to navigate through the control settings
menu.

Set Button (SET) The SET button is used to save

a change made to the product consistency setting.
It is also used to save changes when modifying
control settings.

Left Arrow Button () If the left arrow button is

pressed for 5 seconds, the display will remain lit.
To turn the light off, press the left arrow button for
5 seconds. The left arrow button is used primarily
to navigate through the control settings.

Up Arrow Button () After pressing the SET

button, the up arrow button will change the value
of the product consistency setting. This button
is used primarily to navigate through the control
settings.

Push to Freeze

Green LED

Amber LED

Purge/Clean
Button

SEL Button

SET Button

Left Arrow Button

Up Arrow Button

Figure 3-2 IntelliTec Control

12

3.3 DISASSEMBLY OF MACHINE PARTS

WARNING

Moving machinery can grab, mangle and dismem­ber. Place the Main Freezer Power Off/On switch in
the OFF position before disassembling for cleaning
or servicing.

Before using the machine for the fi rst time, complete
machine disassembly, cleaning and sanitizing proce­dures need to be followed. Routine cleaning intervals
and procedures must comply with the local and state
health codes. Inspection for worn or broken parts should
be made at every disassembly of the machine. All worn
or broken parts should be replaced to ensure safety to
both the operator and the customer and to maintain good
machine performance and a quality product.

To disassemble the machine, refer to the following steps:

A. REMOVE BLENDER (SU412 MODELS)

1. Turn the Main Freezer Power Off/On switch to
the OFF position.

2. Unplug the blender.

3. Remove the blender agitator by holding the blender
shaft and turning the agitator counterclockwise.

4. Loosen knobs holding the blender splash shield
bracket in place and remove the bracket (Fig.
3-3).

B. REMOVE FRONT DOOR AND AUGER

1. Make sure the Main Freezer Power Off/On switch
is in the OFF position

2. Remove the knobs on the front door and remove
the door by pulling it off the studs.

3. Remove the air bleed valve by unscrewing the
knob while holding the valve stem from behind.
Remove the compression spring and push the
air bleed valve through the rear of the front door.

4. Remove the spigot through the bottom of the front
door. Remove all o-rings from the spigot and the
air bleed valve.

5. Remove the plastic bearing from the front auger
support. The plastic bearing may be on the front
door.

6. Remove the auger by pulling slowly. Be careful
not to scratch the inside of the freezing cylinder
when removing the auger.

7. Keep the rear of the auger tipped up once it is
clear of the freezing cylinder to prevent the rear
seal assembly from dropping.

8. Wipe the spline lubricant off of the hex end of the
auger with a paper towel. Remove the rear seal
assembly (Fig. 3-4).

Remove O-Ring

From Inside Insert

Figure 3-3 Removing Splash Shield Bracket

5. Remove the knobs on the front door. Remove
the blender assembly and set aside.

NOTE

Support the blender with one hand while removing
the knobs on the door to prevent the blender from
dropping.

Figure 3-4 Rear Seal Assembly

3.4 CLEANING DISASSEMBLED PARTS

Disassembled machine parts require complete cleaning,
sanitizing and air drying before assembling. Local and state
health codes will dictate the procedure required. Some
state health codes require a four sink process (pre-wash,
wash, rinse, sanitize, air dry), while others require a three
sink process (without the pre-wash step). The following
procedures are a general guideline only. Consult your
local and state health codes for the procedures required
in your location.

A. Disassemble all parts. (Refer to Section 3.4 for

the disassembly of machine parts.)

13

B. Place all front door and auger parts in clean 90° to

110°F (32°C to 43°C) water and wash thoroughly
(four sink procedure only).

CAUTION

Blender motor can NOT be immersed in water or
sanitizer. Wash the motor and mounting bracket
with a mild detergent solution taking care not to
allow water into the motor bearings or seals.

C. Place all parts in 90° to 110°F (32°C to 43°C) mild

detergent water and wash thoroughly.

D. Rinse all parts with clean 90° to 110°F (32°C to

43°C) water.

E. Sanitize all machine parts following procedures

outlined below.

3.5 SANITIZING MACHINE PARTS

A. Use a sanitizer, mixed according to manufacturer’s

instructions, to provide a 100 parts per million
strength solution. Mix sanitizer in quantities of
no less than 2 gallons of 90° to 110°F (32°C to
43°C) water. Any sanitizer must be used only in
accordance with the manufacturer’s instructions.

B. Place all parts in the sanitizing solution for 5

minutes, then remove and let air dry completely
before assembling in machine.

3.7 ASSEMBLING MACHINE

To assemble the machine parts, refer to the following steps:

NOTICE

Petrol-Gel sanitary lubricant or equivalent must be
used when lubrication of machine parts is specifi ed.

NOTICE

The United States Department of Agriculture and
the Food and Drug Administration require that lubri­cants used on food processing equipment be certi­fi ed for this use. Use lubricants only in accordance
with the manufacturer’s instructions.

A. Assemble all o-rings onto parts dry, without

lubrication. Then apply a thin fi lm of sanitary
lubrication to exposed surfaces of the o-rings.

B. Lubricate the rear seal area on the auger shaft

with a thin layer of sanitary lubricant. Install the
rear seal o-ring. Lubricate the outside of the rear
seal o-ring with sanitary lubricant.

C. Install the stainless steel rear seal adapter into

the rear seal dry (without lubricant). Lubricate the
inside surface of the rear seal adapter, including
the adapter o-ring, and install it onto the auger
shaft. DO NOT lubricate the outside of the rear
auger seal (Fig. 3-5).

Petrol-Gel

3.6 CLEANING THE MACHINE

The exterior should be kept clean at all times to preserve
the luster of the stainless steel. A high grade of stainless
steel has been used on the machine to ease cleanup. To
remove spilled or dried mix, wash the exterior with 90° to
110°F (32°C to 43°C) soapy water and wipe dry.

Do not use highly abrasive materials, as they will mar the
fi nish. A mild alkaline cleaner is recommended. Use a soft
cloth or sponge to apply the cleaner. For best results, wipe
with the grain of the steel.

A. Clean the rear seal surface from inside of the

freezing cylinder.

B. Using sanitizing solution and the large barrel

brush provided, sanitize the freezing cylinder by
dipping the brush in the sanitizing solution and
brushing the inside of the freezing cylinder.

C. Remove the rear drip tray by pulling from the side

panel. Clean and replace the drip tray.

Place O-Ring

Inside Insert

Spline

Lubricant

Figure 3-5 Rear Seal Assembly

D. Lubricate the hex drive end of the auger with a

small amount of spline lubricant. A small container
of it is shipped with the machine.

E. Install the two plastic scraper blades onto the

auger and insert into the freezing cylinder.

F. Rotate the auger until it engages the drive shaft.

G. Assemble the air bleed valve o-ring onto the air

bleed valve. Position the o-ring into the groove
close to the wide part. Apply a thin fi lm of sanitary
lubricant to the o-ring.

14

Figure 3-7 Blender Shroud Pin Alignment

Figure 3-6 Front Door Assembly

H. Insert the air bleed valve into the back of the front

door. Install the compression spring onto the air
bleed valve then screw the knob on fi nger tight.

I Install the spigot through the bottom of the front

door.

J. Apply a thin fi lm of sanitary lubricant to the door

seal o-ring, and fi t it into the groove on the rear
of the front door.

K. Apply a thin fi lm of sanitary lubricant to the inside

and outside of the front auger support bushing,
then place it into the front door.

L. Place the front door assembly on the mounting

studs and the push front door against the machine
carefully.

M. Place the blender assembly onto the front door

studs.

N. Secure the front door and the blender assembly

to the machine by placing the knobs on the studs
and alternately tightening opposite corners until
fi nger tight. Do not overtighten. Proper o-ring seal
can be observed through the transparent front
door.

O. On SU412 model, attach the blender shroud to

the blender assembly. The blender shroud has
a pin that needs to be properly aligned with the
machine safety switch (Fig. 3-7).

3.8 SANITIZING

Sanitizing must be done after the machine is clean and
just before the machine is fi lled with mix. Sanitizing the
night before is not effective. However, you should always
clean the machine and parts after using it.

NOTE

The United States Department of Agriculture and
the Food and Drug Administration require that all
cleaning and sanitizing solutions used with food
processing equipment be certifi ed for this use.

When sanitizing the machine, refer to local sanitary regu­lations for applicable codes and recommended sanitizing
products and procedures. The frequency of sanitizing
must comply with local health regulations. Mix sanitizer
according to manufacturer’s instructions to provide a 100
parts per million strength solution. Mix sanitizer in quanti­ties of no less than 2 gallons of 90°F to 110°F (32°C to
43°C) water. Allow sanitizer to contact the surfaces to be
sanitized for 5 minutes. Any sanitizer must be used only
in accordance with the manufacturer’s instructions.

CAUTION

Risk of Product Damage

Avoid prolonged contact of sanitizer with machine
parts. Sanitizer may cause corrosion of stainless
steel parts if there is prolonged contact.

A. Prepare 3 gallons of sanitizing solution following

the manufacturer’s instructions. Pour it into a
clean container and place the container into the
cabinet.

15

Air Bleed

Valve

Figure 3-8 Air Bleed Valve

B. Place the mix pump switch in the ON position

and open the air bleed valve on the front door
by pushing the valve in and holding (see Figure
3-8).

C. Let sanitizing solution fi ll the freezing cylinder to

the air bleed valve. Close the valve by pulling it
out to lock it into place.

D. Place the Main Power OFF/ON and Freezing

Cylinder OFF/ON switches in the ON position.
Press the CLEAN button.

E. Check for leaks when the freezing cylinder is fi rst

pressurized with sanitizing solution.

1. Check for leaks at the front door seals.

2. Check the drain tray located in the side panel
for leaks coming from the rear of the rear auger
seal.

3. Check the inside of the cab unit for leaks at
the hose connections.

F. Using a sanitized soft bristle brush (or equivalent)

dipped in sanitizing solution, clean the mix
container.

G. After fi ve minutes, open the spigot to expel

sanitizing solution. Drain all of the solution from
the machine.

H. When the solution has drained, press the CLEAN

button to stop the auger and place the Main Power
OFF/ON and Freezing Cylinder OFF/ON switches
in the OFF position. Allow the freezing cylinder
to drain completely.

I. On SU412 model, sanitize the agitator and shaft

with a cup of sanitizing solution.

The machine is now sanitized and ready for adding mix.

3.9 INITIAL FREEZE DOWN AND OPERATION

Every Stoelting soft serve machine needs to be set on site.

The following adjustment will provide optimal product
consistency while prolonging product life.

NOTE

The machine is designed for correct operation in
ambient temperatures between 50°F and 110°F.
T emperatures out of that range may cause refrigera­tion problems and product quality issues.

A. ADDING MIX

1. Sanitize the machine immediately before use.

2. Make sure the Freezing Cylinder OFF/ON switch
is in the OFF position.

3. Fill the mix container in the cab with at least 2.5
gallons of mix.

4. Attach the mix inlet probe to the container and
place the container in the refrigerated cab.

5. The mix pump switch is located at the front of the
machine. Place it in the ON position.

6. Place a container under the spigot and open the
spigot to allow the mix to fl ush out about 8 ounces
(0.23 liters) of sanitizing solution and liquid mix.
Close the spigot.

7. Open the air bleed valve on the front door by
pressing and holding. Hold the valve open until
the mix level in the freezing cylinder is 1/2” from
the air bleed valve.

B. PREPARING THE INTELLITEC CONTROL

8. On the IntelliTec control, press and hold the SEL
button for 8 seconds. While still holding the SEL
button, press the up arrow () button. The LCD
will read “DISPLAY”.

9. Press the left arrow () button once. The display
will read “BASIC”.

10. Press the up arrow () button once. The display
will read “CutOut amps”.

11. Press the SET button. A cursor will start blinking
under the far right digit.

12. Change the value to 8.0. Press the left arrow ()
button to move the cursor. Press the up arrow ()
button to increase the digit. When a digit reaches
9, pressing the up arrow () button again will
change the value to 0.

16