Stoelting U421-109I2 Operators Manual

Model U421 & U431
(Ser. #6374 Plus)
Operator’s Manual
513725 Rev.0

Section 1: Introduction

INTRODUCTION

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.

MAINTENANCEPARTS TROUBLESHOOTING OPERATION

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

stoeltingfoodservice.com

Main Tel: [phone]
Fax: [phone]

Customer Service: 888.319.9549
Fax: [phone]
Email: [e-mail]

© 2017 Stoelting

2 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

This manual is divided into the following fi ve sections:

Section 1: Introduction

INTRODUCTION

INTRODUCTION

OPERATION

MAINTENANCE

A. Parts of the Machine

B. Specifi cations

A. Empty the Freezing Cylinders - Start here if cleaning a machine with mix in it

B. Disassemble Parts - Start here if cleaning an empty machine

C. Cleaning Disassembled Parts

D. Cleaning the Machine

E. Assembling the Machine

F. Sanitizing

G. Freeze Down

H. Brushes for Cleaning

I. Lubrication Points

J. Pump Hose Routing

A. Mix Pump Hose Replacement

B. Mix Pump Hose Cleaning

C. Fine Consistency Adjustment

D. Daily Procedures - Night

E. Daily Procedures Morning

MAINTENANCE PARTSTROUBLESHOOTINGOPERATION

TROUBLESHOOTING

PART S

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 3

A. Troubleshooting Flow Charts

A. Auger Shaft & Front Door Parts

B. Cab Tubing

Section 1: Introduction

A. Parts of the U421-I2 Machine

INTRODUCTION

MAINTENANCEPARTS TROUBLESHOOTING OPERATION

IntelliTec2™

Spigot Handle

Front Door

Gate Handles

Freezing Cylinder

Cabinet

IntelliTec2™ Touchpad

The U421 has two types of spigot handles, gate and pull-down. The gate style is opened by moving the handle to the
left. The pull-down style is opened by pulling downwards.

This manual shows the pull-down handles which are self-closing. The gate style handles need to be closed when fi nished
dispensing.

4 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Section 1: Introduction

B. U421-I2 Specifi cations

U421-I2 A/C U421-I2 A/C Remote U421-I2 W/C

Dimensions

width

height

depth

Weight

Electrical

circuit ampacity

(per barrel)

overcurrent protection

device (per barrel)

Compressor

Drive Motor Two - 2 hp

Cooling

Cabinet Volume Two - 8 gallon (30,28 liters)

Freezing Cylinder

Volume

Machine with crate Machine with crate Machine with crate

26-3/4’’

(67,9 cm)

68-3/4’’

(174,6 cm)

39-1/2’’

(100,3 cm)

785 lbs

(356,0 kg)

1 PH 3 PH 1 PH 3 PH 1 PH 3 PH

32A 20A

50A 30A

34’’

(86,4 cm)

78’’

(198,1 cm)

48’’

(121,9 cm)

930 lbs

(421,8 kg)

26-3/4’’

(67,9 cm)

67-3/4’’

(172,1 cm)

39-3/4’’

(101,0 cm)

760 lbs

(344,7 kg)

36A Left /
31A Right

50A Left /
45A Right

(86,4 cm)

(198,1 cm)

(121,9 cm)

930 lbs

(421,8 kg)

The machine requires one dedicated electrical circuit per barrel.

Two - 19,000 Btu/hr

Cabinet - 1,300 Btu/hr Compressor (R-134a)

Air cooled units require 6” (15,2 cm) air
space on all sides and open at the top.

Remote air cooled requires two remote

condensers and two precharged line

sets.

Two - 1.33 gallon (5,03 liters)

34’’

78’’

48’’

26-3/4’’

(67,9 cm)

67-1/2’’

(171,5 cm)

39-1/2’’

(100,3 cm)

760 lbs

(344,7 kg)

34’’

(86,4 cm)

78’’

(198,1 cm)

48’’

(121,9 cm)

930 lbs

(421,8 kg)

20A 32A 20A

30A 50A 30A

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 per barrel. Ideal EWT of

50°-70°F. The machine requires 6” (15,2

cm) air space on all sides for the cabinet

refrigeration system.

INTRODUCTION

MAINTENANCE PARTSTROUBLESHOOTINGOPERATION

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 5

Section 1: Introduction

C. Parts of the U431-I2 Machine

INTRODUCTION

MAINTENANCEPARTS TROUBLESHOOTING OPERATION

Spigot Handle

IntelliTec2™

Front Door

Gate Handles

Freezing Cylinder

Cabinet

IntelliTec2™ Touchpad

The U431 has two types of spigot handles, gate and pull-down. The gate style is opened by moving the handle to the
left. The pull-down style is opened by pulling downwards.

This manual shows the pull-down handles which are self-closing. The gate style handles need to be closed when fi nished
dispensing.

6 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Section 1: Introduction

D. U431-I2 Specifi cations

U431-I2 A/C U431-I2 A/C Remote U431-I2 W/C

Dimensions

width

height

depth

Weight

Electrical

circuit ampacity

(per barrel)

overcurrent protection

device (per barrel)

Compressor

Drive Motor Two - 2 hp

Cooling

Cabinet Volume Two - 8 gallon (30,28 liters)

Freezing Cylinder

Volume

Machine with crate Machine with crate Machine with crate

26-3/4''

(67,9 cm)

68-3/4''

(174,6 cm)

39-1/2''

(100,3 cm)

785 lbs

(356,0 kg)

1 PH 3 PH 1 PH 3 PH 1 PH 3 PH

32A 20A

50A 30A

34''

(86,4 cm)

78''

(198,1 cm)

48''

(121,9 cm)

935 lbs

(424,1 kg)

26-3/4''

(67,9 cm)

67-3/4''

(172,1 cm)

39-3/4''

(101,0 cm)

760 lbs

(344,7 kg)

36A Left /

31A Right

50A Left /
45A Right

The machine requires one dedicated electrical circuit per barrel.

Two - 19,000 Btu/hr

Cabinet - 1,300 Btu/hr Compressor (R-134a)

Air cooled units require 6" (15,2 cm) air

space on all sides and open at the top.

Remote air cooled requires two remote

condensers and two precharged line

sets.

Two - 1.33 gallon (5,03 liters)

34''

(86,4 cm)

78''

(198,1 cm)

48''

(121,9 cm)

930 lbs

(421,8 kg)

26-3/4''

(67,9 cm)

67-1/2''

(171,5 cm)

39-1/2''

(100,3 cm)

760 lbs

(344,7 kg)

20A 32A 20A

30A 50A 30A

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 per barrel. Ideal EWT of

50°-70°F. The machine requires 6" (15,2

cm) air space on all sides for the cabinet

refrigeration system.

34''

(86,4 cm)

78''

(198,1 cm)

48''

(121,9 cm)

930 lbs

(421,8 kg)

INTRODUCTION

MAINTENANCE PARTSTROUBLESHOOTINGOPERATION

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 7

Section 2: Operation

A. Empty the Freezing Cylinders

A.1

Turn off freezing cylinders.

A.2

OPERATION INTRODUCTION

MAINTENANCEPARTS TROUBLESHOOTING

In the cab, remove the mix
pickup assemblies and place
them in a bucket fi lled with cool
tap water.

Remove the mix containers
and covers.

Optional: Fill the bucket with Stera Sheen
solution to make cleaning parts easier
after disassembly.

Clean mix containers on a regular basis.
Refer to State and local health codes for
frequency.

NOTE

NOTE

A.4

Open spigots to drain product
into a container until the
container is full. Empty the
container and repeat until
product has been drained from
the freezing cylinders.

A.5

Refi ll the bucket in the cab with cool tap water (or
Stera Sheen). Allow the freezing cylinders to fi ll then
drain the water into a container. Repeat until the water
draining from the freezing cylinders is clear.

NOTE

If the “Clean Time Exceeded” warning
is displayed on the IntelliTec2™, turn
the freezing cylinder on and off again
and press the Clean button to clear the
warning.

A.7

A.3

Press the Clean buttons.

8 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Remove any remaining
water from the bucket in the
cabinet.

Drain the water and press
the Clean buttons to stop
the augers.

A.8

Remove the buckets in the cab
and turn on the pumps to clear
any remaining liquid in the hoses.

Open the spigots to drain the
freezing cylinders.

A.9

Press and hold the Main
Freezer Power button for
three seconds to turn off
the power.

Section 2: Operation

Auger Flight Wear

1. Front Door Disassembly

B.1

Remove the spigot
extensions or rosette
caps if installed.

OPERATIONINTRODUCTION

MAINTENANCE PARTSTROUBLESHOOTING

B. Disassemble Parts

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 regulations. 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. Check the wear line on the auger
fl ights on a regular basis and replace as needed.

Unscrew the knobs
on the front door and
remove the door.

B.2

Remove the front
door o-rings and
remove the spigots
from the front door.

B.3

Remove the air bleed
valve from the front
door.

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 9

Section 2: Operation

B.4

Remove all o-rings from
parts by fi rst wiping off the
lubrication using a clean
towel. Then squeeze the
o-ring upward to form a
loop. Roll the o-ring out of
the groove.

2. Removing Auger

B.5

OPERATION INTRODUCTION

Remove front auger
supports and bushings
and remove the augers
from the freezing cylinders.
As the augers are being
pulled out, remove the
plastic fl ights with springs.

3. Disassemble Pump Hose

B.8

Disconnect the sensor
connectors from the
pickup assemblies
and unscrew the hose
clamps nearest the
assemblies.

Remove the mix pickup
assemblies.

B.9

Remove the lock
clips from the check
valves and remove
the check valves and
springs.

MAINTENANCEPARTS TROUBLESHOOTING

B.6

Wipe any remaining
lubricant off the hex end
of the auger and remove
the rear seal assembly
and o-ring. Wipe any
remaining lubricant off
the o-ring and auger.

Remove the rear seal
adapter from the rear seal.

B.7

Unscrew springs
from the auger
fl ights.

Detach the check
valve from the spring.

B.10

Remove the o-rings from the
assemblies.

B.11

If the pump hoses require cleaning and inspection,
follow the steps in Section 3.

10 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Section 2: Operation

C. Cleaning Disassembled Parts

Disassembled 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 pre­wash step). The following procedures are a general
guideline only. Consult your local and state health
codes for the procedures required in your location.

C.1

Place all parts in 90° to 110°F
(32°C to 43°C) mild detergent
water and wash thoroughly. Use

the brushes that shipped with
the machine to clean all holes in

the front door, fl ights, mix pickup
assembly, etc.

D. Cleaning the Machine

D.1

Using a detergent solution
and the large barrel
brush provided, clean
the freezing cylinders by
dipping the brush in the
solution and brushing
the inside of the freezing
cylinders.

Make sure to thoroughly clean the rear seal surfaces
on the inside of the freezing cylinders.

D.2

Wrap the brush in a clean cloth and thoroughly dry
the freezing cylinder.

D.3

OPERATIONINTRODUCTION

MAINTENANCE PARTSTROUBLESHOOTING

NOTE

Be sure to use the brushes that shipped
with the machine to properly clean the
parts.

C.2

Rinse all parts with clean 90° to 110°F (32°C to 43°C)
water. Then place all parts in a sanitizing solution for at
least 1 minute, then remove and let air dry completely
before assembling in machine.

Remove the drain tray from the
side of the machine. Remove the
drip tray from the front panel.
Clean and replace the trays.

D.4

The exterior of the machine 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)
mild detergent 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.

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 11

Section 2: Operation

E. Assembling Machine

NOTE

Total Blend or equivalent must be used
when lubrication of machine parts is
specifi ed.

The USDA and FDA require that lubricants
used on food processing equipment must
be certifi ed for this use. Use lubricants
only in accordance with the manufacturer’s
instructions.

OPERATION INTRODUCTION

NOTE

Stoelting recommends allowing the parts
to air dry before assembling.

E.1

Install the rear seal o-rings onto the augers. Lubricate
the outside of the o-rings with a generous amount of

MAINTENANCEPARTS TROUBLESHOOTING

sanitary lubricant.

E.2

Install the stainless steel adapter into the rear seal
WITHOUT LUBRICANT. Then lubricate the inside of
the adapter and install it onto the auger.

DO NOT lubricate the outside of the rear seal.

E.3

Lubricate the hex end of the auger with Total Blend.

12 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Section 2: Operation

E.4

Screw the springs onto
the studs in the plastic
fl ights. The springs must
be screwed into the
fl ights completely to provide
proper compression.

E.5

Install the two plastic
fl ights onto the rear of
the auger and insert
it part way into the
freezing cylinder.

E.7

Apply a thin layer of sanitary lubricant to the inside
and outside of the auger support bushing.

OPERATIONINTRODUCTION

MAINTENANCE PARTSTROUBLESHOOTING

E.6

Install the remaining
plastic fl ights, push the
auger into the freezing
cylinder and rotate slowly
until the auger engages
the drive shaft.

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 13

Section 2: Operation

E.8

Install the bushing onto the
auger support and install the
auger support into the front
of the auger. Rotate the auger
support so that one leg of the
support points straight up.

OPERATION INTRODUCTION

E.9

Assemble the air bleed valve o-ring onto the air bleed
valve. Position the o-ring into the groove. Apply a thin
fi lm of sanitary lubricant to the o-ring.

E.10

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.

E.11

Install the o-rings onto the spigots. Apply a thin layer
of sanitary lubricant to the o-rings on the spigot bodies
and install the spigot bodies through the bottom of
the front door.

MAINTENANCEPARTS TROUBLESHOOTING

E.12

Fit the front door
o-rings into the
grooves on the rear
of the front door.

14 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Section 2: Operation

E.13

Place the front door
assembly on the
mounting studs and the
push front door against
the machine carefully.

NOTE

Make sure the pins on the front door do
not touch the legs of the auger supports.

E.14

Secure the front door to
the machine by placing
the knobs on the studs
and tightening until
fi nger tight. Tighten in
a crisscross pattern.
Do not overtighten.
Proper o-ring seal can
be observed through the
transparent front door.

E.15

Assemble the mix pickup
assemblies:

1. Install the o-rings onto the
mix pickup tubes and apply
a thin layer of sanitary
lubricant to the o-rings.

2. Install the rubber check
valves into the springs and
insert (spring fi rst) into the
check valve bodies.

3. Insert the mix pickup
tubes into the check valve
bodies and secure them
with the lock clips.

E.16

Place the mix containers on
the shelf in the cabinet.

OPERATIONINTRODUCTION

MAINTENANCE PARTSTROUBLESHOOTING

E.17

Install the mix pickup
assemblies in the cab using
the hose clamps.

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 15

Section 2: Operation

F. Sanitizing

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

The United States Department of
Agriculture and the Food and Drug

OPERATION INTRODUCTION

MAINTENANCEPARTS TROUBLESHOOTING

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 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 and to provide a 100
parts per million strength solution.

NOTE

F. 2

Press the Main Power
button. Then press the
Pump buttons to turn the
pumps ON.

F. 3

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 seal of the auger.

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

F. 4

After you hear the pump
shut off, press the air
bleed valves to release
the air pressure. Allow
water to fi ll the freezing
cylinders.

F. 1

Prepare 2 gallons of
sanitizing solution
for each freezing
cylinder. Following the
sanitizer manufacturer’s
instructions for preparing
the sanitizing solution.

Pour the sanitizing
solution into the mix containers.

16 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

F. 5

Press the CLEAN buttons to
start the augers rotating. The
IntelliTec2™ display shows a
5-minute timer.

Section 2: Operation

F. 6

While the cylinders are being sanitized complete the
following:

1. Use a sanitized soft bristle brush dipped in sanitizing
solution to clean the mix containers.

2. Empty the sanitizer from the containers.

3. Install the mix pickup
assemblies into the covers
using the retaining clips. Install
the mix sensor wires onto the
assemblies.

4. Install spigot extensions and
rosette capes (if applicable).

F. 7

After the fi ve minute timer expires, open the spigots
to drain the sanitizing solution into
a container.

When the solution has drained,
press the Pump and Clean buttons
to stop the pump and auger. Allow
the freezing cylinder to drain
completely. The machine is now
sanitized and ready for adding mix.

G.1

Fill each mix container with
at least 3 gallons of mix.

Close the cab door.

Press the Pump buttons to
turn the pumps on.

OPERATIONINTRODUCTION

G.2

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.

MAINTENANCE PARTSTROUBLESHOOTING

G.3

Allow cylinders to fi ll until
the pumps shut off . Press the
valves to release pressure
in the cylinders.

The cylinders will be fi lled
to the proper level after the
pumps shut off the second
time.

G. Freeze Down

Sanitize immediately before use.

Make sure the display shows the freezing cylinders
are off . If they are not, press the On/Off Left or On/Off
Right button to turn them off .

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 17

G.4

Press the On/Off buttons
to turn on the freezing
cylinders then press the
Push to Freeze buttons.

When the product is ready,
the display will read “SERVE” or “SERVE 2”. Open the
spigot to dispense product.

Section 2: Operation

I. Lubrication Points

O-Ring

OPERATION INTRODUCTION

O-Ring & Hex

End of Auger

MAINTENANCEPARTS TROUBLESHOOTING

Inside & Outside

of Bushing

ONLY Inside

Metal Adapter

All O-Rings*

* U431 spigot bodies shown, U421 have two spigots

18 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

J. Pump Hose Routing

Black Cover Clamp

Black Cover Clamp

Mix Sensor

Mix Sensor

1/2" Clear Tube

1/2" Clear Tube

Section 2: Operation

OPERATIONINTRODUCTION

3/8" Clear Tube

3/8" Clear Tube

Check Valve

Check Valve

Mix Pickup Assembly

Mix Pickup Assembly

Check Valve Block

Check Valve Block

Tan Pump Hose

Tan Pump Hose

MAINTENANCE PARTSTROUBLESHOOTING

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 19

Section 3: Maintenance

A. Mix Pump Hose Replacement

NOTE

Replace pump hose every 800 gallons or
every 2 weeks, whichever occurs fi rst.

Replace the hose during the cleaning
process.

A.1

Turn the pump on and pull down
on the pickup end of the tan
hose until a few inches of tubing
is visible. The pickup end is on
the left side.

Then turn the pump off .

A.3

Turn the pump on and pull the hose out of the black
cover.

Then turn the pump off .

A.4

Rotate the pump rollers so one of the
rollers is at the 6:00 position.

With a brush, clean the roller
assembly with detergent water, then
with clear water.

MAINTENANCEPARTS TROUBLESHOOTING OPERATION INTRODUCTION

A.2

Loosen the clamps on the tan
hose at the mix sensor and check
valve block.

Disconnect the hose at both
ends.

A.5

Connect a new length of tan hose
to the mix sensor using a clamp.

20 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

A.6

Turn the pump on and feed the other
end of the tan hose into the left side
of the black cover.

Face the natural curve of the tan hose
towards the outside of the cover to
prevent the hose from looping around
twice.

A.7

Section 3: Maintenance

As the hose feeds through the cover, orient the mix
sensor at an angle so the sensor wire is not kinked
or bent at a sharp angle.

Then turn the pump off .

Connect the hose to the check valve block.

A.8

Press and hold the Pump
buttons until the pump hose
reset message appears on
the screen.

MAINTENANCE PART STROUBLESHOOTINGOPERATIONINTRODUCTION

A.9

Continue normal cleaning and sanitizing procedures.

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 21

Section 3: Maintenance

B. Mix Pump Hose Cleaning

NOTE

Any cleaning procedure must always be
followed by sanitizing before fi lling the
machine with mix.

The mix pump is approved for CIP (clean-in-place). It
is thoroughly cleaned when the cleaning solution is
pumped through the machine.

WARNING

Hazardous Moving Parts

MAINTENANCEPARTS TROUBLESHOOTING OPERATION INTRODUCTION

Revolving pump head can grab, mangle, and cause
serious crushing injury. Make sure the display shows
the freezing cylinders and pump are off . If they are
not, press the On/Off button and Pump button to turn
them off .

1. Disassembly and Hose Cleaning

B.1

Disconnect the wires from the
low mix sensor.

B.2

Turn the pump on and pull down
on the pickup end of the tan
hose until a few inches of tubing
is visible. The pickup end is on
the left side.

Then turn the pump off .

Loosen the clamp on the tan hose
and disconnect the hose at the
low mix sensor.

CAUTION

System Under Pressure

Never disconnect hoses from the machine or the pump
without fi rst opening the spigot to relieve pressure.

22 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

B.3

Turn the mix pump on and pull the tan house out of
the black cover clamp then turn the mix pump off .

Section 3: Maintenance

B.4

Unfasten the wire clamp on the
check valve block by swinging
the clamp to the right. Remove
the check valve.

B.5

Loosen the clamp on the mix tube at the top of the
cab and remove the hose from the tube.

2. Inspect and Cleaning

B.8

Inspect all the parts for wear and replace as necessary.

B.9

Thoroughly clean the parts with 90° to 110°F detergent
water and brushes provided. Rinse with clean, 90° to
110°F water.

MAINTENANCE PART STROUBLESHOOTINGOPERATIONINTRODUCTION

B.10

B.6

Remove the two o-rings from the
base of the check valve block.

B.7

Remove the hose assemblies from the cab.

Loosen all clamps and disconnect all hoses from the
low mix sensor and check valve block.

Wash the mix tube and the check
valve base in the cabinet with the
detergent water and brushes.
Rinse with clean, 90° to 110°F
water.

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 23

Section 3: Maintenance

3. Reassembly

B.11

Connect the clear hose to the
low mix sensor.

B.12

Connect the tan hose to the low mix sensor.

NOTE

Face the natural curve of the tan hose
towards the outside of the cover to prevent
the hose from looping around twice.

B.14

Once the hose feeds through the cover, turn the
pump off .

B.15

Connect the tan hose to the bottom of the check
valve block. The bottom of the block has the smaller
hose connector.

B.13

MAINTENANCEPARTS TROUBLESHOOTING OPERATION INTRODUCTION

Turn the pump on and feed the
tan hose into the left side of the
black cover clamp.

24 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Section 3: Maintenance

B.16

Install the o-rings onto the base of the check valve
block. Apply a thin layer of sanitary lubricant to the
o-rings.

B.18

Install the check valve into the
block and secure the block with
the wire clamp. Make sure the
rubber check valve is installed in
the bottom seat of the assembly.

B.19

Adjust the clear hose so that it is not kinked and tighten
the clamp holding the hose to the mix tube.

MAINTENANCE PART STROUBLESHOOTINGOPERATIONINTRODUCTION

B.20

B.17

Connect the clear hose to the top of the check valve
block and tighten the clamp.

Insert the other end of the clear hose onto the mix
tube at the top of the cabinet. Do not tighten the clamp
until the check valve block is installed.

Connect the low mix sensor wires
to the sensor

B.21

Sanitize assembled machine as per instructions
outlined in Section 2 F.

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 25

Section 3: Maintenance

C. Fine Consistency Adjustment

Product consistency can be adjusted on the Fine
Consistency Adjustment Screen.

C.1

From the Current
Status screen, press
the left arrow button to
access the password
screen.

Press the right arrow
then the SEL button.

C.2

C.3

Press the SET button to save the changes.

Press the SEL button to toggle between freezing
cylinders.

C.4

Press the left arrow button when done to return to the
Current Status screen.

MAINTENANCEPARTS TROUBLESHOOTING OPERATION INTRODUCTION

Press the SET
button on the
Fine Consistency
Adjustment screen.
And use the arrows
to change the value.

Increase the value for higher consistency (thicker).
Change the +/- symbol to “-” and adjust the value for
lower consistency (thinner) product.

Make adjustments in increments of 5 for best results.
Allow 3-4 draws or 30 minutes for the changes to
take eff ect.

26 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Section 3: Maintenance

Daily Procedures

D. Daily Procedures - Night E. Daily Procedures - Morning

D.1

Remove the drip tray from
the front panel. Clean the
tray and reinstall it.

D.2

Remove the spigot extensions. Clean and sanitize
them and let them air dry.

D.3

Clean the underside of the clear front door and the
exposed portion of the spigots with mild detergent
water and then with sanitizing solution.

E.1

Clean the underside of the clear front door and the
exposed portion of the spigots with brushes and a
mild detergent water and then with sanitizing solution.

E.2

Install the spigot extensions.

E.3

MAINTENANCE PART STROUBLESHOOTINGOPERATIONINTRODUCTION

Check the mix level of the mix bags in the cab.

Add new mix bags as necessary.

E.4

D.4

Wipe the exterior clean with a mild detergent water to
remove spilled or dried mix and wipe dry.

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 27

Press the Push To Freeze
button to start freezing the
product.

When the product is ready,
the display will read “SERVE”
or “SERVE 2”. Open the
spigot to dispense product.

Section 4: Troubleshooting

Product is Too

Increase the fine

consistency.

OPERATION INTRODUCTION

Is the product still

MAINTENANCEPART S TROUBLESHOOTING

too Soft?

Soft

Yes

Is there an air flow

restriction around

the machine?

Product is Too

Firm

Decrease the fine

consistency.

Is the product still

too firm?

No

Continue normal

operation.

No

Yes

Contact your authorized

Stoelting distributor for

further assistance

No

Yes

Move anything blocking

the louvered panels and

make sure there is

enough air clearance

around the machine.

Continue normal

operation.

28 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Yes

Is the problem

fixed?

No

Contact your authorized

Stoelting distributor for

further assistance

Section 4: Troubleshooting

If an error code appears on the machine complete the steps on the following pages before calling your authorized
Stoelting distributor. Oftentimes the issues can be resolved using new/fresh product in a clean and sanitized machine.

Any Error Code

on IntelliTec2™

Go to the flow chart

for the error code

Make sure the mix is fully thawed

and the hoses are connected

properly.

Turn the power off using the Main Freezer

Power button. Make sure the electrical plug is

secure in the outlet. Turn the power back on.

Freeze the product and test.

Is there still an

error code?

Yes

OPERATIONINTRODUCTION

Error Code (E2)

High Torque

Error Code (E3) Run Time

Air-Cooled Machines

MAINTENANCE PARTSTROUBLESHOOTING

Error Code (E3) Run Time

Water-Cooled Machines

Error Code (E9) High

Pressure Cutout

Air-Cooled Machines

Error Code (E9) High

Pressure Cutout

No

Continue normal operation.

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 29

Water-Cooled Machines

Contact your authorized
Stoelting distributor for further
assistance for all other codes.

Section 4: Troubleshooting

Error Code (E3)

Run Time

Air-Cooled Machines

Move anything blocking

Is there an air flow

restriction around

OPERATION INTRODUCTION

Yes

the machine?

the louvered panels and

make sure there is

enough air clearance

around the machine.

Is the problem

fixed?

Yes

MAINTENANCEPART S TROUBLESHOOTING

No

Does the error

occur immediately

after assembling?

No

Contact your authorized

Stoelting distributor for

further assistance

Yes

Disassemble machine

and reassemble

following the steps in the

operators manual.

No

Is the problem

fixed?

No

Continue normal operation.

Yes

30 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Error Code (E3)

Run Time

Water-Cooled Machines

Section 4: Troubleshooting

Is the water or

glycol system

turned off?

No

Are the water or

glycol lines kinked

or damaged?

No

Repair or replace the

lines.

Is the problem

fixed?

No

Is the problem

fixed?

No

YesYes Turn the system on.

YesYes

OPERATIONINTRODUCTION

MAINTENANCE PARTSTROUBLESHOOTING

Does the error

occur immediately

after assembling?

No

Contact your authorized

Stoelting distributor for

further assistance

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 31

Yes

Disassemble machine

and reassemble

following the steps in the

operators manual.

Is the problem

fixed?

No

Yes

Continue normal operation.

Section 4: Troubleshooting

Error Code (E9)

High Pressure Cutout

Air-Cooled Machines

Move anything blocking
the louvered panels and

make sure there is

enough air clearance

around the machine.

OPERATION INTRODUCTION

Is there an air flow

restriction around

the machine?

Yes

Is the problem

fixed?

Yes

MAINTENANCEPART S TROUBLESHOOTING

No

Check for an exterior heat source

from equipment. Examples include:

• Ice Machine

• Grill

• Hot Dog Steamer

Is there an

exterior heat

source?

No

Contact your authorized

Stoelting distributor for

further assistance

Yes

Move equipment that

increases the ambient

temperature away from

the machine.

No

Is the problem

fixed?

No

Continue normal operation.

Yes

32 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Error Code (E9)

High Pressure Cutout

Water-Cooled Machines

Section 4: Troubleshooting

OPERATIONINTRODUCTION

Is the water or

glycol system

turned off?

No

Are the water or

glycol lines kinked

or damaged?

No

Repair or replace the

lines.

Is the problem

fixed?

No

Is the problem

fixed?

No

YesYes Turn the system on.

MAINTENANCE PARTSTROUBLESHOOTING

YesYes

Contact your authorized

Stoelting distributor for

further assistance

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 33

Continue normal operation.

Section 5: Replacement Parts

A.1

694200

694200

482004

482004

MAINTENANCEPART S TROUBLESHOOTING OPERATION INTRODUCTION

U421-I2 Auger Shaft & Front Door Parts

667868

381804

381804

2183106

2183106

2187696

2187696

2204252

2204252

624598

624598

Part Number Description Quantity

149003 Bushing - Front Auger Support 2
381804 Auger Flight 12
482004 Knob (Air Bleed Valve) 2
482019 Knob - Front Door (Black) 4
624520 O-Ring - Air Bleed Valve - Black 2
624598 O-Ring - Spigot - Black 4
624678 O-Ring - Rear Seal - Black 2
625133 O-Ring - Front Door - Black 2
667868 Seal - Rear Auger (Orange) 2
694200 Spring - Air Bleed Valve 2
694255 Spring - Auger Flight 12
1151859 Adapter - Rear Seal (Code 1) 2
2183106 Valve - Air Bleed 2
2104552 Support - Front Auger 2
2187696 Front Door 2
2204252 Spigot Body 2
4151178 Auger Shaft 2

624520

624520

482019

482019

2104552

2104552

625133

625133

149003

149003

4151178

4151178

694255

694255

624678

624678

667868

1151859

1151859

34 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

Section 5: Replacement Parts

A.2

482004

482004

694200

694200

624664

624664

624614

624614

U431-I2 Auger Shaft & Front Door Parts

381804

381804

2110116

2110116

694255

624520

624520

2187811

2187811

Part Number Description Quantity

149003 Bushing - Front Auger Support 2
381804 Auger Flight 12
482004 Knob (Air Bleed Valve) 2
482019 Knob - Front Door (Black) 4
624520 O-Ring - Air Bleed Valve - Black 2
624598 O-Ring - Outside Spigot - Black 4
624614 O-Ring - Top & Bottom Center Spigot - Black 2
624664 O-Ring - Middle Center Spigot - Black 1
624678 O-Ring - Rear Seal - Black 2
625133 O-Ring - Front Door - Black 2
667868 Seal - Rear Auger (Orange) 2
694200 Spring - Air Bleed Valve 2
694255 Spring - Auger Flight 12
1151859 Adapter - Rear Seal (Code 1) 2
2104552 Support - Front Auger 2
2110116 Valve - Air Bleed 2
2177427 Front Door 1
2187811 Spigot Body - Center 1
2187812 Spigot Body - Outer 2
4151178 Auger Shaft 2

482019

482019

2104552

2104552

2187812

2187812

624598

624598

625133

625133

149003

149003

2177427

2177427

694255

4151178

4151178

624678

624678

1151859

1151859

667868

667868

MAINTENANCE PART STROUBLESHOOTINGOPERATIONINTRODUCTION

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 35

Section 5: Replacement Parts

35

A.2

MAINTENANCEPART S TROUBLESHOOTING OPERATION INTRODUCTION

Cab Tubing

756088

264235

2208043

2208043

756079

264241

264241

696152

696152

762256

762256

Part Number Description Quantity

264235 Clamp - Metal (1/4” ID Tubing) ­ 264241 Clamp - Metal (1/2” ID Tubing) ­ 558109 Mix Container Only 2
624607-5 O-Ring - Check Valve Body - Black (5 Pack) 4
624616-5 O-Ring - Check Valve Block - Lower - Black (5 Pack) 2
624644-5 O-Ring - Check Valve Block - Upper - Black (5 Pack) 2
694247 Spring - Check Valve 2
696152 Clip - Lock (Check Valve) 2
756079 Tubing - 3/8” ID - Clear 2
756088 Tubing - 1/2” ID - Clear 2
756204 Tubing - 1/4” ID - Pump (50’ Box Only) (Per Inch) ­ 756204-24 Tubing - 1/4” ID - Pump (Pre-Cut 24” Piece) 2
762256 Check Valve 2
2206611 Check Valve Block 2
2208043 Sensor - Mix 2
1172864 Check Valve - Mix In Line (Outer) 2
2177274 Clip - Retaining (Mix Probe To Cover) 2
2203792 Pick-Up Tube - Mix 2
3177229 Cover - Rear (Mix Container) 2
3177262 Cover - Front (Mix Container) 2

756079

264235

1172864

1172864

694247

694247

2203792

2203792

756088

624607

624607

264241

264241

264241

264235

264235

2642

694247

694247

2206611

2206611

762256

762256

624644

624644

624619

624619

36 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 37

DOMESTIC WARRANTY
(Including Mexico)

1. Scope:
Stoelting, A Vollrath Company (“Stoelting”) warrants to the first user (the “Buyer”) that the Stoelting-branded freezer

equipment (the “Equipment”) will be free from defects in materials and workmanship under normal use and proper
maintenance for the period listed below in the Warranty Period section. All warranty periods begin on the date of original
install or one (1) year from the shipping date, whichever occurs first. This warranty is subject to all conditions,
exceptions, and limitations contained herein.

2. Disclaimer of Other Warranties:

THIS WARRANTY IS EXCLUSIVE; AND STOELTING HEREBY DISCLAIMS ANY IMPLIED WARRANTY
OF MERCHANTABILITY OR FITNESS FOR PARTICULAR PURPOSE.

3. Remedies:
Stoelting’s sole obligations, and Buyer’s sole remedies, for any breach of this warranty shall be, at Stoelting’s option,

one of the following: repair or replacement of the affected component at Stoelting’s plant in Kiel, Wisconsin, or refund
of the purchase price of the affected Equipment. Stoelting, through an Authorized Stoelting Provider, will
deinstall/reinstall the affected component from/into the equipment (“Labor”) for the period listed below in the Warranty
Period section. These obligations/remedies are subject to the conditions that Buyer (a) signs and returns to Stoelting,
upon installation, the Start-Up and Training Checklist for the affected equipment, (b) gives Stoelting prompt written
notice of any claimed breach of warranty within the applicable warranty period, and (c) delivers th e affected equipment
to Stoelting or its designated service location, in its original packaging/crating, also within that period. Buyer shall bear
the cost and risk of shipping to and from Stoelting’s plant or designated service location.

4. Warranty Period:

Equipment Part Part W arranty Peri od La bo r W arranty Pe ri od

Soft Serve & Shak e Five (5) Years Twelve (12) Months

Frozen Unc arbonat ed

Beverage

Custard & Batch Two (2) Years Twelve (12) Months

Dipping Cabinets &

Display Cabinets

Frozen B everage /

Granita Dispenser

AutoV end All components Twelve (12) Months Twelve (12) Months

Crème Whi ppers Two (2) Years Twelve (12) Months

All equi pm ent

Freezing Cylinders
Hoppers
Compressors
Drive Motors
Speed Reducers
Augers
Evaporator
Compressors
Drive Motors
Speed Reducers
Freezing Cylinders
Hoppers
Compressors
Drive Motors
Speed Reducers
Beaters
Auger Shafts

All components Twelve (12) Months Twelve (12) Months
Compress ors Five (5) Years

Elec tronic B oard Three (3) Years
All other component s Two (2) Years

Compressors
Motors
Condensers

All other component s
not s pec i fied above

Five (5) Years Twelve (12) Months

Twelve (12) Months

Twelve (12) Months Twelve (12) Mont hs

Page 1 of 2 SFWARR-013 Revision 08

38 U421-I2 & U431-I2 OPERATOR’S MANUAL 513725 REV.0

DOMESTIC WARRANTY
(Including Mexico)

5. Conditions:
a) If the date of the original installation cannot be verified, these warranty periods begin one (1) year from the shipping date. It is

the responsibility of the seller to disclose this information to the Buyer at the time of sale.

b) Stoelting shall not be responsible to provide any remedy under this warranty with respect to any component that fails by reason

of negligence, abnormal use, misuse or abuse, faulty repair made by others, use with parts or equipment not manuf actured or
supplied by Stoelting, any modification or alteration of any parts or equipment, or damage in transit.

c) This warranty is valid only if the Equipment is installed and serviced by an Authorized Stoelting Provider and only if new, genuine

Stoelting parts are used.

d) The Equipment installation location must have suitable conditions as explained i n the Stoelting o perators manual, specifi cat ion

sheet, and/or technical manual including but not limited to, ambient temperature, water supply parameters, and space

requirements.
e) The Authorized Stoelting Provider must return defective parts, at Stoelting’s discretion, for credit.
f) Any refrigerant other than that specified on the Equipment model identification nameplate voids this warranty.

6. Exceptions:
This warranty does NOT cover any of the following:

a) Costs associated with installation labor, disposal of equipment being replaced, and shipping costs of replacement parts or

Equipment.
b) Cleaning, maintenance or lubrication of the Equipment as outlined in the Stoeltin g operators manual.
c) This warranty does not extend to parts, sometimes called “wear parts”, which are generally expected to deteriorate and to require

replacement as equipment is used, including, but limited to, o-rings, auger flights, auger seals, auger support bushings, and

drive belts. All such parts are sold AS IS.
d) External components including, but not limited to, hoses, piping, or electrical equipment.
e) Labor and travel charges due to return trips or waiting if the Authorized Stoelting Provider is prevented from promptly starting

service work upon arrival. This exception includes labor charges incurred for limited access facilities including, but not limited to,

government and military buildings, and airports.
f) Failure, damage, or repairs due to faulty installation, misapplication, abuse, lack of service, or improper service, unauthorized

alteration, improper operation as indicated in the Stoelting operators manual, including, but not limited to, failure to properly

assemble and/or clean, improper tool usage, or use of unapproved lubrication, or cleaning and sanitizing supplies.
g) Any costs associated with electricity, including utility increases, from any reason whatsoever.
h) Damage resulting from the use of refrigerant other than that specified on the Equipment model identification nameplate.
i) T he use of this equipment as a rental asset. Use as a rental asset negates all warranties associated with the equipment.
j) Any special, indirect or consequential property or commercial damage of any nature whatsoever, if the jurisdiction allows this

exclusion.
k) Costs not covered by Stoelting’s travel pay policy; Stoelting covers only the first trip travel which is a flat rate by mileage one-

way from the service company’s home location, or closest location to the job site. The flat rate is calculated as follows:

o 0-50 Miles $85
o 51-110 Miles $127
o 111-160 Miles $165
o Over 160 Miles The maximum reimbursed by Stoelting is $165

Any travel costs not covered may be invoiced to the customer.

7. Limitations:

THE REMEDIES SET FORTH IN THIS WARRANTY SHALL BE THE SOLE LIABILITY STOELTING AND THE

EXCLUSIVE REMEDY OF BUYER WITH RESPECT TO EQUIPMENT SUPPLIED BY STOELTING; AND IN NO

EVENT SHALL STOELTING BE LIABLE FOR ANY INCIDENTAL OR CONSEQUENTIAL DAMAGES, INCLUDING

AS EXAMPLES BUT NOT INTENDED TO BE LIMITED TO DOWNTIME, OVERHEAD, MATERIALS,

PERFORMANCE PENALTIES, LOST SALES, LOST PROFITS, PRODUCT LOSS, OR PROPERTY DAMAGES,

WHETHER FOR BREACH OF WARRANTY OR OTHER CONTRACT BREACH, NEGLIGENCE OR OTHER TORT,

OR ON ANY STRICT LIABILITY THEORY.

Page 2 of 2 SFWARR-013 Revision 08

513725 REV.0 U421-I2 & U431-I2 OPERATOR’S MANUAL 39