Stoelting U421 series, U431-I2 W/C, U431 series, U431-I2 A/C, U431-I2 A/C Remote Operator's Manual

Model U421 & U431
Operator’s Manual
513713 Rev.0

Section 1: 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 INTRODUCTION

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

stoeltingfoodservice.com

White Glove Service Network
Phone: [phone]

© 2017 Stoelting

2 U421-I2A & U431-I2A OPERATOR’S MANUAL 513713 REV.0

This manual is divided into the following fi ve sections:

Section 1: 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 PARTSTROUBLESHOOTINGOPERATIONINTRODUCTION

TROUBLESHOOTING

PART S

513713 REV.0 U421-I2A & U431-I2A 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-I2A Machine

IntelliTec2™

Spigot Handle

Front Door

Swing Gate Style Handles

MAINTENANCEPARTS TROUBLESHOOTING OPERATION INTRODUCTION

Freezing Cylinder

Cabinet

IntelliTec2™ Touchpad

The U421 has two types of spigot handles, swing gate and pull-down. The swing 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 swing gate style handles need to be closed when
fi nished dispensing.

4 U421-I2A & U431-I2A OPERATOR’S MANUAL 513713 REV.0

B. U421-I2A Specifi cations

U41-I2A A/C U421-I2A A/C Remote U421-I2A W/C

Dimensions

width

height

depth

Weight

Electrical

circuit ampacity

(per barrel)

overcurrent protection

device (per barrel)

Compressor

Drive Motor Two - 2 hp

Cooling

Hopper 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

(86,4 cm)

(198,1 cm)

(121,9 cm)

908 lbs

(411,8 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)

Section 1: Introduction

34’’

78’’

48’’

20A 32A 20A

30A 50A 30A

26-3/4’’

(67,9 cm)

67-1/2’’

(171,5 cm)

39-1/2’’

(100,3 cm)

760 lbs

(344,7 kg)

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)

908 lbs

(411,8 kg)

MAINTENANCE PARTSTROUBLESHOOTINGOPERATIONINTRODUCTION

513713 REV.0 U421-I2A & U431-I2A OPERATOR’S MANUAL 5

Section 1: Introduction

C. Parts of the U431-I2A Machine

Spigot Handle

IntelliTec2™

Front Door

Swing Gate Style Handles

MAINTENANCEPARTS TROUBLESHOOTING OPERATION INTRODUCTION

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

Freezing Cylinder

Cabinet

IntelliTec2™ Touchpad

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

6 U421-I2A & U431-I2A OPERATOR’S MANUAL 513713 REV.0

D. U431-I2A 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

Hopper 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)

Section 1: Introduction

34''

(86,4 cm)

78''

(198,1 cm)

48''

(121,9 cm)

908 lbs

(411,8 kg)

20A 32A 20A

30A 50A 30A

26-3/4''

(67,9 cm)

67-1/2''

(171,5 cm)

39-1/2''

(100,3 cm)

760 lbs

(344,7 kg)

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)

908 lbs

(411,8 kg)

MAINTENANCE PARTSTROUBLESHOOTINGOPERATIONINTRODUCTION

513713 REV.0 U421-I2A & U431-I2A OPERATOR’S MANUAL 7

Section 2: Operation

NOTE

The machine must be emptied,
disassembled, cleaned and sanitized
every 3 days or per local health code
requirements (whichever is sooner).

A. Empty the Freezing Cylinders

A.1

Turn off freezing cylinders.

A.2

MAINTENANCEPARTS TROUBLESHOOTING OPERATION INTRODUCTION

In the cab, lift the drawer latches
and pull out the drawers.

A.3

Set up cab and hoses for rinse procedure.

1. Remove the bags from the cab
and store them in a cooler.

2. Remove the three plastic bins
from the cab.

3. Remove the drawers. To
remove a drawer, pull it
out. Tilt the drawer up to
disengage the front rollers.
Pull it further out then up to
disengage the rear rollers.

A.4

Fill a bucket with 2 gallons of cool
tap water and place the coiled
hoses with bag adapters into
the bucket.

Disconnect the bag adapters
from the bags and place caps
on the bags

NOTE

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

NOTE

disassembly.

Wire trays are located at the upper left and
right corners of the cab to store bag caps.

A.5

Press the Clean buttons.

Make sure the display
shows that the mix pumps
are on

8 U421-I2A & U431-I2A OPERATOR’S MANUAL 513713 REV.0

Section 2: Operation

A.6

Open spigots to drain product
until no product is visible through
the front door. Refi ll the bucket
with water as necessary.

NOTE

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

A.7

Remove the buckets to help
clear any remaining liquid in
the hoses.

A.9

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

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.

MAINTENANCE PARTSTROUBLESHOOTINGOPERATIONINTRODUCTION

Drain the water from the
freezing cylinders and press
the Clean and Pump buttons
to stop the augers.

A.8

Open the spigots to release
any pressure in the freezing
cylinders (machines with gate
style handles).

Auger Flight Wear

513713 REV.0 U421-I2A & U431-I2A OPERATOR’S MANUAL 9

Section 2: Operation

1. Front Door Disassembly

B.1

Remove the spigot
extensions or rosette
caps if installed.

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.

2. Removing Auger

B.5

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.

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.

MAINTENANCEPARTS TROUBLESHOOTING OPERATION INTRODUCTION

B.3

Remove the air bleed
valve from the front
door.

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.

Remove the rear seal
adapter from the rear seal.

B.7

Unscrew springs
from the auger
fl ights.

NOTE

The pump hose must be replaced every
800 gallons or every two weeks, whichever
occurs fi rst. Go to Section 3 A for pump
hose replacement instructions.

10 U421-I2A & U431-I2A OPERATOR’S MANUAL 513713 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

MAINTENANCE PARTSTROUBLESHOOTINGOPERATIONINTRODUCTION

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.

513713 REV.0 U421-I2A & U431-I2A OPERATOR’S MANUAL 11

Section 2: Operation

E. Assembling Machine

NOTE

Total Blend lubricant 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.

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 OPERATION INTRODUCTION

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.

12 U421-I2A & U431-I2A OPERATOR’S MANUAL 513713 REV.0

E.3

Lubricate the hex end of the auger with Total Blend
lubricant.

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 Total Blend lubricant to the inside
and outside of the auger support bushing.

MAINTENANCE PARTSTROUBLESHOOTINGOPERATIONINTRODUCTION

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.

513713 REV.0 U421-I2A & U431-I2A OPERATOR’S MANUAL 13

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.

Section 2: Operation

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 Total Blend lubricant to the o-ring.

E.11

Install the o-rings onto the spigot bodies and apply a
thin layer of Total Blend lubricant to the o-rings . Install
the spigot bodies through the bottom of the front door.

MAINTENANCEPARTS TROUBLESHOOTING OPERATION INTRODUCTION

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.12

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

14 U421-I2A & U431-I2A OPERATOR’S MANUAL 513713 REV.0