RNS012 & RNS020
Manitowoc
Nugget Ice Machines
Technician’s
Handbook
This manual is updated as new information and models are
released. Visit our website for the latest manual.
www.manitowocice.com
America’s #1 Selling Ice Machine
Part Number STH044 10/13
Safety Notices
!
Warning
!
Caution
Important
As you work on Manitowoc equipment, be sure to pay
close attention to the safety notices in this handbook.
Disregarding the notices may lead to serious injury
and/or damage to the equipment.
Throughout this handbook, you will see the following
types of safety notices:
Text in a Warning box alerts you to a potential
personal injury situation. Be sure to read the
Warning statement before proceeding, and work
carefully.
Text in a Caution box alerts you to a situation in
which you could damage the equ ipment. Be sure
to read the Caution statement before proceeding,
and work carefully.
Procedural Notices
As you work on Manitowoc equipment, be sure to read
the procedural notices in this handbook. These notices
supply helpful information which may assist you as
you work.
Throughout this handbook, you will see the following
types of procedural notices:
Text in an Important box provides you with
information that may help you perform a
procedure more efficiently. Disregarding this
information will not cause damage or injury, but it
may slow you down as you work.
NOTE: Text set off as a Note provides you with simple,
!
Caution
Important
! Warning
but useful, extra information about the procedure you
are performing.
Read These Before Proceeding:
Proper installation, care and maintenance are
essential for maximum performance and troublefree operation of your Manitowoc equipment. Visit
our website www.manitowocfsg.com for manual
updates, translations, or contact information for
service agents in your area. If you encounter
problems not covered by this manual, do not
proceed, contact Manitowoc Foodservice Group.
We will be happy to provide assistance.
Routine adjustments and maintenance
procedures outlined in this handbook are not
covered by the warranty.
PERSONAL INJURY POTENTIAL
Do not operate equipment that has been
misused, abused, neglected, damaged, or
altered/modified from that of original
manufactured specifications.
! Warning
Read this manual thoroughly before operating,
!
Warning
!
Warning
! Warning
! Warning
installing or performing maintenance on the
equipment. Failure to follow instructions in this
manual can cause property damage, injury or
death.
Do not use electrical appliances or accessories
other than those supplied by Manitowoc for your
ice machine model.
Two or more people or a lifting device are
required to lift this appliance.
This equipment contains high voltage electricity
and refrigerant charge. Installation and repairs are
to be performed by properly trained technicians
aware of the dangers of deali ng with high voltage
electricity and refrigerant under pressure. The
technician must also be certified in proper
refrigerant handling and servicing procedures. All
lockout and tag out procedures must be followed
when working on this equipment.
Do not damage the refrigeration circuit when
installing, maintaining or servicing the unit.
! Warning
Do not operate equipment that has been
! Warning
! Warning
! Warning
! Warning
misused, abused, neglected, damaged, or
altered/modified from that of original
manufactured specifications. This appliance is
not intended for use by persons (including
children) with reduced physical, sensory or
mental capabilities, or lack of experience and
knowledge, unless they have been given
supervision concerning use of the applianc e by a
person responsible for their safety. Do not allow
children to play with this appliance.
All covers and access panels must be in place
and properly secured, before operating this
equipment.
Do not obstruct machine vents or openings.
Do not store gasoline or other flammable vapors
or liquids in the vicinity of this or any other
appliance.
Do not clean with water jet.
! Warning
It is the responsibility of the equipment owner to
!
Warning
perform a Personal Protective Equipment Hazard
Assessment to ensure adequate protection
during maintenance procedures.
When using electric appliances, basic
precautions must always be followed, including
the following:
a. Read all the instructions before using
the appliance.
b. To reduce the risk of injury, close
supervision is necessary when an
appliance is used near children.
c. Do not contact moving parts.
d. Only use attachments recommended or
sold by the manufacturer.
e. Do not use outdoors.
f. For a cord-connected appliance, the
following must be included:
• Do not unplug by pulling on cord. To
unplug, grasp the plug, not the cord.
• Unplug from outlet when not in use
and before servicing or clean i ng .
• Do not operate any appliance with a
damaged cord or plug, or after the
appliance malfunctions or is dropped
or damaged in any manner. Contact
the nearest authorized service facility
for examination, repair, or electrical
or mechanical adjustment.
g. Follow applicable lock out tag out
procedures before working on
equipment.
h. Connect to a properly grounded outlet
only.
Table of Contents
General Information
Model Numbers . . . . . . . . . . . . . . . . . . . . .5
Model/Serial Number Location . . . . . . . .5
Manitowoc Cleaner and Sanitizer . . . .5
Ice Machine Warranty Information . . .6
Commercial Warranty . . . . . . . . . . . . . . .6
Residential Warranty . . . . . . . . . . . . . . . .9
Installation
Location of Ice Machine . . . . . . . . . . . . . .13
Ice Machine Clearance Requirements . .14
Ice Machine Heat of Rejection . . . . . . . . .14
Electrical Service . . . . . . . . . . . . . . . . . . .15
Circuit Ampacity . . . . . . . . . . . . . . . . .15
Ice Machine Head Section Water
Supply and Drains . . . . . . . . . . . . . . . . . .16
Potable Water Supply . . . . . . . . . . . . .16
Potable Water Inlet Lines . . . . . . . . . .16
Operation
Ice Making Sequence of Operation . . . . .19
Drain Connections . . . . . . . . . . . . . . . .17
RNS012 - RNS020 Nugget Machines .19
Touch Pad Sequence of Operation . . .21
Sequence of Operation Chart . . . . . . .22
Water Level Check . . . . . . . . . . . . . . .23
Part Number STH044 10/13 1
Maintenance
Manitowoc’s Cleaning Technology . . . . 26
Exterior Cleaning . . . . . . . . . . . . . . . . 27
Preventative Maintenance Procedure . . 28
Heavily Scaled Cleaning Procedure . . . . 31
Cleaning And Sanitizing Procedure . . . . 33
Component Disassembly For Cleaning And
Sanitizing . . . . . . . . . . . . . . . . . . . . . . . . . 36
General Information . . . . . . . . . . . . . . 36
Water Dump Valve . . . . . . . . . . . . . . . 50
Cleaning the Condenser . . . . . . . . . . . 52
Removal from Service/Winterization . . . 53
General . . . . . . . . . . . . . . . . . . . . . . . . 53
Troubleshooting
SafeGuard Feature . . . . . . . . . . . . . . . . . . 55
SafeGuards . . . . . . . . . . . . . . . . . . . . . . . 57
No Water . . . . . . . . . . . . . . . . . . . . . . 57
No Ice Production . . . . . . . . . . . . . . . . 58
Ice Machine Will Not Run Diagnostics . . 60
Refrigeration Diagnostics . . . . . . . . . . . . 66
Before Beginning Service . . . . . . . . . . 66
Installation/Visual Inspection Checklist 66
Water System Checklist . . . . . . . . . . . 67
Ice Production/Quality Check . . . . . . . 68
Analyzing Discharge Pressure . . . . . . 69
Analyzing Suction Pressure . . . . . . . . 71
2 Part Number STH044 10/13
Component Check Procedures
Main Fuse . . . . . . . . . . . . . . . . . . . . . .73
ICE/OFF/CLEAN Toggle Switch . . . . .74
Float Switch . . . . . . . . . . . . . . . . . . . . .75
Ice Damper and Hall Effect Switches .76
Selector Switch . . . . . . . . . . . . . . . . . .79
Dispense Lever Activated . . . . . . . . . .79
Touchless Sensor Activated . . . . . . . .80
Dispense Switch . . . . . . . . . . . . . . . . .82
Touchless Sensor . . . . . . . . . . . . . . . .83
High Pressure Cutout Control . . . . . . . 84
Fan Cycle Control . . . . . . . . . . . . . . . .85
Low Pressure Cutout (LPCO) Control . 86
Compressor Electrical Diagnostics . . .87
Diagnosing Start Components . . . . . .89
Refrigerant Recovery/Evacuation . . . . . .91
Normal Self-Contained Procedures . . .91
System Contamination Clean-Up . . . . . .95
Determining Severity Of Contamination 95
Cleanup Procedure . . . . . . . . . . . . . . .97
Replacing Pressure Controls Without Re-
moving Refrigerant Charge . . . . . . . . . 100
Part Number STH044 10/13 3
Component Specifications
Main Fuse . . . . . . . . . . . . . . . . . . . . . . 103
ICE/OFF/CLEAN Toggle Switch . . . . . 103
High Pressure Cutout (HPCO) Control 103
Filter-Driers . . . . . . . . . . . . . . . . . . . . . 103
Total System Refrigerant Charge . . . . . . 104
Charts
Cycle Times/24-Hour Ice Production/
Refrigerant Pressure Charts . . . . . . . . . . 105
RNS012A/RNS020A . . . . . . . . . . . . . . 106
Diagrams
Wiring Diagrams . . . . . . . . . . . . . . . . . . . 107
RNS012/RNS020 115/60/1 & 230/50/1 108
Electronic Control Board . . . . . . . . . . . . 109
RNS012 - RNS020 Control Board . . . 109
Refrigeration Tubing Sche matic . . . . . . 111
RNS012 - RNS020 . . . . . . . . . . . . . . . 111
4 Part Number STH044 10/13
General Information
!
Caution
Model Numbers
Self-Contained Air-Cooled
RNS012A - Air-cooled lever dispense model
RNS012AT - Air-cooled touchless dispense model
RNS020A - Air-cooled lever dispense model
RNS020AT - Air-cooled touchless dispense model
Model/Serial Number Location
These numbers are required when requesting
information from your local Manitowoc Distributor,
service representative, or Manitowoc Ice, Inc. The
model and serial number are listed on the OWNER
WARRANTY REGISTRATION CARD. They are also
listed on the MODEL/SERIAL NUMBER DECAL
affixed to the ice machine.
MANITOWOC CLEANER AND SANITIZER
Manitowoc Ice Machine Cleaner and Sanitizer are
available in 16 oz. (473 ml) bottles. These are the only
cleaners and sanitizer approved for use with
Manitowoc products.
Nugget models must use cleaner part number
000000084 ONLY (clear cleaner). Damage to the
evaporator will result with repeated use or high
concentrations of standard (green) cleaner. This
damage is not covered by the warranty.
Cleaner Part Number Sanitizer Part Number
16 oz. 000000084 16 oz. 94-0565-3
1 gal N/A 1 gal. 94-0581-3
Part Number STH044 10/13 5
ICE MACHINE WARRANTY INFORMATION
Important
Owner Warranty Registration Card
Warranty coverage begins the day the ice machine is
installed.
Complete and mail the OWNER WARRANTY
REGISTRATION CARD as soon as possible to
validate the installation date.
If the OWNER WARRANTY REGISTRATION CARD is
not returned, Manitowoc will use the date of sale to the
Manitowoc Distributor as the first day of warranty
coverage for your new ice machine.
Commercial Warranty
Manitowoc Ice (hereinafter referred to as the
"COMPANY") warrants for a period of twenty four
months from the installation date (except as limited
below) that new Flake/Chiplet ice machines
manufactured by the COMPANY shall be free of
defects in material or workmanship under normal and
proper use and maintenance as specified by the
COMPANY and upon proper installation and start-up
in accordance with the instruction manual supplied
with the ice machine. The COMPANY'S warranty
hereunder with respect to the compressor shall apply
for an additional thirty-six mo nt hs, excluding all labor
charges.
The obligation of the COMPANY under this warranty is
limited to the repair or replacement of parts,
components, or assemblies that in the opinion of the
COMPANY are defective. This warranty is further
limited to the cost of parts, components or assemblies
and standard straight time labor charges at the
servicing location.
6 Part Number STH044 10/13
Time and hourly rate schedules, as published from
time to time by the COMPANY, apply to all service
procedures. Additional expenses including without
limitation, travel time, overtime premium, material cost,
accessing or removal of the ice machine, or shipping
are the responsibility of the owner, along with all
maintenance, adjustments, cleaning, and ice
purchases. Labor covered under this warranty must be
performed by a COMPANY Contracted Service
Representative or a refrigeration service agency as
qualified and authorized by the COMPANY'S local
Distributor . The COMPANY'S liability under this
warranty shall in no event be greater than the actual
purchase price paid by customer for the ice machine.
The foregoing warranty shall not apply to (1) any part
or assembly that has been altered, modified, or
changed; (2) any part or assembly that has been
subjected to misuse, abuse, neglect, or accidents; (3)
any ice machine that has been installed and/or
maintained inconsistent with the technical instructions
provided by the COMPANY; or (4) any ice machine
initially installed more than five years from the serial
number production date. This warranty shall not apply
if the Ice Machine's refrigeration system is modified
with a condenser, heat reclaim device, or parts and
assemblies other than those manufactured by the
COMPANY, unless th e COMPANY approves these
modifications for specific locations in writing.
THIS WARRANTY IS IN LIEU OF ALL OTHER
WARRANTIES OR GUARANTEES OF ANY KIND,
EXPRESSED OR IMPLIED, INCLUDING ANY
IMPLIED WARRANTY OF MERCHANTABILITYOR
FITNESS FOR A PARTICULAR PURPOSE. In no
event shall the COMP ANY be liable for any special,
indirect, incidental or consequential damages. Upon
the expiration of the warranty period, the COMP ANY'S
liability under this warranty shall terminate. The
foregoing warranty shall constitute the sole liability of
the COMPANY and the exclusive remedy of the
customer or user.
Part Number STH044 10/13 7
To secure prompt and continuing warranty service, the
warranty registration card must be completed and sent
to the COMPANY within five (5) days from the
installation date.
Complete the following and retain for your record:
Distributor/Dealer
Model Number Serial Number
Installation Date
MANITOWOC ICE
2110 So. 26th St., P.O. Box 1720, Manitowoc, WI 54220
Telephone: 920-682-0161 • Fax: 920-683-7585
Web Site - www.manitowocice.com
8 Part Number STH044 10/13
Residential Warranty
WHAT DOES THIS LIMITED WARRANTY COVER?
Subject to the exclusions and limitations below,
Manitowoc Ice (“Manitowoc”) warrants to the original
consumer that any new ice machine manufactured by
Manitowoc (the “Product”) shall be free of defects in
material or workmanship for the warranty period
outlined below under normal use and maintenance,
and upon proper installation and start-up in
accordance with the instruction manual supplied with
the Product.
HOW LONG DOES THIS LIMITED WARRANTY
LAST?
Product Covered Warranty Period
Ice Machine
Twelve months from the
sale date
WHO IS COVERED BY THIS LIMITED WARRANTY?
This limited warranty only applies to the original
consumer of the Product and is not transferable.
Part Number STH044 10/13 9
WHAT ARE MANITOWOC ICE’S OBLIGATIONS
UNDER THIS LIMITED WARRANTY?
If a defect arises and Manitowoc receives a valid
warranty claim prior to the expiration of the warranty
period, Manitowoc shall, at its option: (1) repair the
Product at Manitowoc’s cost, including standard
straight time labor charges, (2) replace the Product
with one that is new or at least as functionally
equivalent as the original, or (3) refund the purchase
price for the Product. Replacement parts are
warranted for 90 days or the balance of the original
warranty period, whichever is longer. The foregoing
constitutes Manitowoc’s sole obligation and the
consumer’s exclusive remedy for any breach of this
limited warranty . Manitowoc’s liability under this limited
warranty is limited to the purchase price of Product.
Additional expenses including, without limitation,
service travel time, overtime or premium labor
charges, accessing or removing the Product, or
shipping are the responsibility of the consumer.
HOW TO OBTAIN WARRANTY SERVICE
To obtain warranty service or information regarding
your Product, please contact us at:
MANITOWOC ICE
2110 So. 26th St. P.O. Box 1720, Manitowoc, WI
54221-1720
Telephone: 920-682-0161 Fax: 920-683-7585
www.manitowocice.com
10 Part Number STH044 10/13
WHAT IS NOT COVERED?
This limited warranty does not cover, and you are
solely responsible for the costs of: (1) periodic or
routine maintenance, (2) repair or replacement of the
Product or parts due to normal wear and tear, (3)
defects or damage to the Product or parts resulting
from misuse, abuse, neglect, or accidents, (4) defects
or damage to the Product or parts resulting from
improper or unauthorized alterations, modifications, or
changes; and (5) defects or damage to any Product
that has not been installed and/or maintained in
accordance with the instruction manual or technical
instructions provided by Manitowoc. To the extent that
warranty exclusions are not permitted under some
state laws, these exclusions may not apply to you.
EXCEPT AS STATED IN THE FOLLOWING SENTENCE, THIS
IMITED WARRANTY IS THE SOLE AND EXCLUSIVE
L
W
ARRANTY OF MANITOWOC WITH REGARD TO THE
P
RODUCT. ALL IMPLIED WARRANTIES ARE STRICTLY
IMITED TO THE DURATION OF THE LIMITED WARRANTY
L
A
PPLICABLE TO THE PRODUCTS AS STATED ABOVE,
I
NCLUDING BUT NOT LIMITED TO, A NY WARRANTY OF
ERCHANTABILITY OR OF FITNESS FOR A PARTICULAR
M
P
URPOSE.
Some states do not allow limitations on how long an
implied warranty lasts, so the above limitation may not
apply to you.
Part Number STH044 10/13 11
IN NO EVENT SHALL MANITOWOC OR ANY OF ITS
A
FFILIATES BE LIABLE TO THE CONSUMER OR ANY
THER PERSON FOR ANY INCIDENTAL, CONSEQUENTIAL
O
O
R SPECIAL DAMAGES OF ANY KIND (INCLUDING,
W
ITHOUT LIMITATION, LOSS OF PROFITS, REVENUE OR
USINESS) ARISING FROM OR IN ANY MANNER
B
C
ONNECTED WITH THE PRODUCT, ANY BREACH OF THIS
L
IMITED WARRANTY, OR ANY OTHER CAUSE
HATSOEVER, WHETHER BASED ON CONTRACT, TORT
W
O
R ANY OTHER THEORY OF LIABILITY.
Some states do not allow the exclusion or limitation of
incidental or consequential damages, so the above
limitation or exclusion may not apply to you.
HOW STATE LAW APPLIES
This limited warranty gives you specific legal rights,
and you may also have rights that vary from state to
state or from one jurisdiction to another.
REGISTRATION CARD
To secure prompt and continuing warranty service, this
warranty registration card must be completed and sent
to Manitowoc within thirty (30) days from the sale date.
Complete the registration card and send it to
Manitowoc.
12 Part Number STH044 10/13
Installation
!
Warning
PERSONAL INJURY POTENTIAL
Remove all ice machine panels before lifting and
installing.
Location of Ice Machine
The location selected for the ice machine must meet
the following criteria. If any of these criteria are not
met, select another location.
• The location must be indoors.
• The location must be free of airborne and other
contaminants.
• The air temperature must be at least 45°F (7°C),
but must not exceed 110°F (43°C).
• The water temperature must be at least 45°F
(7°C), but must not exceed 90°F (32°C).
• The location must not be near heat-generating
equipment or in direct sunlight.
• The location must be capable of supporting the
weight of the ice machine and a full bin of ice.
• The location must allow enough clearance for
water, drain and electrical connections in the rear
of the ice machine.
• The location must not obstruct airflow through or
around the ice machine. Refer to the chart below
for clearance requirements.
• The ice machine must be protected if it will be
subjected to temperatures below 32°F (0°C).
Failure caused by exposure to freezing
temperatures is not covered by the warranty. See
“Removal from Service/Winterization”
Part Number STH044 10/13 13
Ice Machine Clearance Requirements
RNS012 - RNS020 Self-Contained Air-Cooled
Top 24" (61.0 cm)
Sides 8" (20.3 cm)
Back 5" (12.7 cm)
RNS012 - RNS020 airflow is in the left side and out the top.
Ice Machine Heat of Rejection
Series
Ice Machine
RNS012 - RNS020 2,300
* BTU/Hour
Because the heat of rejection varies during the ice making cycle,
the figure shown is an average.
Heat of Rejection*
Air Conditioning
Ice machines, like other refrigeration equipment, reject
heat through the condenser. It is helpful to know the
amount of heat rejected by the ice machine when
sizing air conditioning equipment where self-contained
air-cooled ice machines are installed.
14 Part Number STH044 10/13
Electrical Service
!
Warning
!
Warning
General
All wiring must conform to local, state and national
codes.
Voltage
The maximum allowable voltage variation is ± 10% of
the rated voltage on the ice machine model/serial
number plate at start-up (when the electrical load is
highest).
Fuse/Circuit Breaker
A separate fuse/circuit breaker mu st be provided for
each ice machine. Circuit breakers must be H.A.C.R.
rated (does not apply in Canada).
The ice machine must be grounded in accordance
with national and local electrical codes.
CIRCUIT AMPACITY
The minimum circuit ampacity is used to help select
the wire size of the electrical supply. (Minimum circuit
ampacity is not the ice machine’s running amp load.)
The wire size (or gauge) is also dependent upon
location, materials used , len gt h of run, etc., so it must
be determined by a qualified electrician.
Self Contained Air-Cooled
Ice
Machine
RNS012
RNS020
Voltage
Phase Cycle
115/1/60 15 10.3
230/1/50 15 4.6
Max. Fuse/
Circuit
Breaker
Total
Amps
Part Number STH044 10/13 15
Ice Machine Head Section Water
Important
Supply and Drains
POTABLE WATER SUPPLY
The ice machine must be connected to a potable water
supply only. Local water conditions may require
treatment of the water to inhibit scale formation, filter
sediment, remove chlorine, and improve taste and
clarity.
If you are installing a Manitowoc water filter system,
refer to the Installation Instructions supplied with the
filter system for ice making water inlet connections.
POTABLE WATER INLET LINES
Follow these guidelines to install water inlet lines:
• Do not connect the ice machine to a hot water
supply . Be sure all hot water restrictors installed for
other equipment are working. (Check valves on
sink faucets, dishwashers, etc.)
• If water pressure exceeds the maximum
recommended pressure of 80 psig (5.5 Bar),
obtain a water pressure regulator from your
Manitowoc Distributor.
• Install a wa ter shut-of f valve and uni on for both the
ice making and condenser water lines.
• Insulate water inlet lines to prevent condensation.
16 Part Number STH044 10/13
DRAIN CONNECTIONS
Follow these guidelines when installing drain lines to
prevent drain water from flowing back into the ice
machine and storage bin:
• Drain lines must have a 1.5 in. (3.8 cm) drop per 5
ft. of run (2.5 cm per meter), and must not create
traps.
• The floor drain must be large enough to
accommodate drainage from all drains.
• Run separate bin and water-cooled condenser
drain lines. Insulate them to prevent condensation.
• Vent the bin drain to the atmosphere. Do not vent
the condenser drain on water-cooled models.
• Drains must have a union or other suitable means
to allow a place of disconnection from the ice
machine when servicing is required.
Part Number STH044 10/13 17
18 Part Number STH044 10/13
This Page Intentionally Left Blank
Operation
Ice Making Sequence of Operation
RNS012 - RNS020 NUGGET MACHINES
Ice Making Sequence of Operation
PRIOR TO STARTUP
When the toggle switch is placed in the ICE position
the following must occur in the listed order before ice
making will start.
• The 15 minute delay period must be expired. The
delay period starts upon application of power or a
change in toggle switch position.
• The ice chute damper must be in the closed or
down position.
• The water sensing switch must be closed (water
reservoir full of water and water sensing float in the
up position).
INITIAL STARTUP
A 15 minute delay period must expire. The delay
period starts to time out upon application of power and
can not be overridden. When the five minute delay
period expires, the gear motor energizes. The water in
the reservoir closes the water sensing (float switch)
and the compressor and condenser fan motor
energize.
FREEZE CYCLE
The float valve automatically maintains the water level
in the reservoir . The ice damper will open and close to
verify ice production. The ice machine will continue to
make ice until the ice damper is held open (up) as ice
fills the bin.
Part Number STH044 10/13 19
AUTOMATIC SHUTOFF
When the ice damper is held open by ice, the gear
motor, compressor and condenser fan de-energize.
The five minute delay period starts to time out. The ice
machine will remain off until the 15 minute delay
period expires and the ice damper closes.
RESTART AFTER AUTOMATIC SHUTOFF
The 15 minute delay period must be expired. The
delay period starts when the ice machine enters
Automatic Shutoff and can not be overridden.
1. The ice machine was off for less than 30 minutes.
When the 15 minute delay period expires, the gear
motor , compressor and condenser fan motor energize.
2. The ice machine was off for more than 30
minutes.
The gear motor and dump valve energize to drain the
water from the evaporator and reservoir. After 30
seconds the dump valve de-energizes. When the
reservoir fills with water, the water sensing switch
closes and the compressor and condenser fan motor
energize.
CHANGING TOGGLE SWITCH POSITION IN THE
FREEZE CYCLE
Moving the toggle switch from ICE to OFF will start a
15 minute delay period.
• Moving the toggle switch immediately to the ICE
position - The ice machine waits 15 minutes then
starts.
• Moving the toggle switch to the ICE position after
15 minutes have elapsed - The ice machine
immediately starts.
20 Part Number STH044 10/13
Control Board Features
FLUSH CYCLE
After the ice machine has completed 50 hours of run
time a flush sequence will start. This cycle will drain
and refill the evaporator to remove minerals that have
settled to the bottom of the evaporator. The flush
sequence lasts approximately 21 minutes, after which
the ice machine will reset the 50 hour counter and
automatically start ice making again.
POWER INTERRUPTION DELAY
If power is disconnected the ice machine stops. When
power is reapplied a 15 minute delay is initiated.
MAINTENANCE REQUIRED INDICATOR
The maintenance required light on Nugget Ice
Machines will energize and flash after 10,000 hours of
run time. The ice machine will need to be serviced to
ensure future reliability.
SAFEGUARDS
The ice machine control board has safety features to
protect the ice machine from severe failures. The ice
machine will stop when conditions arise that would
cause major component failure. Refer to Safeguards
for details.
TOUCH PAD SEQUENCE OF OPERATION
Step 1 The control board monitors the touch pad.
Pressing/selecting Ice, Water, or Ice & Water will
energize the corresponding blue Led selection and
waits for dispense lever or touchless sensor activation.
Step 2 Depressing the dispense lever or activating
the touchless sensor closes the relay selected with the
touch pad. Depending on selection, either the water
solenoid, ice dispense motor or both components
activate.
Part Number STH044 10/13 21
22 Part Number STH044 10/13
SEQUENCE OF OPERATION CHART
Nugget Machines
Sequence
Contactor
Coil
Dump
Valve
Gear
Motor
Ice Damper Duration
Initial Start-Up
The 15 minute delay must expire
first
Off Off On Closed Immediate
Freeze Cycle On Off On
Moves to Verify
Ice Production
Until Ice Holds Damper
Open
Automatic Shut-Off Off Off Off Open Until Damper Closes
WATER LEVEL CHECK
The float valve maintains the correct water level. The
water level is factory set and normally will not require
adjustment. The water level is correct if the Water
Level indicator light is energized and no water is
entering the overflow tube.
The float valve is secured with 2 stop nuts. If an
adjustment is required raise or lower the stop nuts as
needed.
Part Number STH044 10/13 23
24 Part Number STH044 10/13
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Maintenance
!
Caution
!
Caution
!
Warning
!
Warning
Maintenance procedures or failures due to a lack of
maintenance are not covered by the warranty.
Manitowoc Ice Machine Cleaner and Sanitizer are the
only products approved for use in Manitowoc ice
machines.
Use the correct Manitowoc approved metal safe Ice
Machine Cleaner (part number 000000084) and
Sanitizer (part number 94-0565-3). It is a violation of
Federal law to use these solutions in a manner
inconsistent with their labeling. Read and
understand all labels printed on bottles before use.
Do not mix Cleaner and Sani tize r solutio ns toge ther.
It is a violation of Federal law to use these solutions
in a manner inconsistent with their labeling.
Wear rubber gloves and safety goggles (and/or face
shield) when handling ice machine Cleaner or
Sanitizer.
If you do not understand the procedures or the
safety precautions that must be followed, call your
local Manitowoc Distributor or Manitowoc Ice.
Part Number STH044 10/13 25
Manitowoc’s Cleaning Technology
Manitowoc RNS012 - RNS020 Ice Machines allow the
initiation and completion of a cleaning cycle at the flip
of a switch. This cycle will permit cleaning of all
surfaces that come in contact with the water
distribution system. Periodic maintenance must be
performed that includes sanitizing the bin and adjacent
surface areas, which are not contacted by the water
distribution system.
Depending on local water conditio ns Manitowoc
recommends initiating preventative maintenance
cleaning procedures between the 6 month cleanings.
This preventive maintenance removes mineral buildup from the evaporator, which results in peak
efficiency and lower operating costs.
This technology allows initiation and completion of a
clean cycle, after which the ice machine automatically
starts ice making again.
There are three separate cleaning procedures.
Heavily Scaled Cleaning Procedure
Perform this procedure if you have some or all of these
symptoms.
• Grinding, popping or squealing noises from the
evaporator.
• Grinding noise from gearbox.
• Ice machine trips speed sensor.
A Cleaning/Sanitizing Procedure must be performed
after this procedure.
Cleaning/Sanitizing Procedure
This procedure must be performed a minimum of once
every six months:
• All ice must be removed from the bin/dispenser.
• The ice machine and bin/dispenser must be
disassembled, cleaned and sanitized.
• The ice machine produces ice with the cleaner and
sanitizer solutions.
• All ice produced during the cleaning and sanitizing
procedure must be discarded
26 Part Number STH044 10/13
Preventative Maintenance Cleaning Procedure
Perform this procedure as often as required for your
water conditions:
• Allows cleaning the ice machine without removing
all of the ice from the bin/dispenser.
• Removes mineral deposits from areas that are in
direct contact with water during the Freeze cycle
(reservoir , evaporator, auger, drain lines).
EXTERIOR CLEANING
Clean the area around the ice machine as often as
necessary to maintain cleanliness and efficient
operation. Use cleaners designed for use with
stainless steel products.
Sponge any dust and dirt off the outside of the ice
machine with mild soap and water. Wipe dry with a
clean, soft cloth.
Heavy stains should be removed with stainless steel
wool. Never use plain steel wool or abrasive pads.
They will scratch the panels.
WEEKLY
Remove grill from scrap ice tray and wipe splash
panel, scrap ice tray and grill with sanitizer & water
solution. Pour excess solution in scrap ice tray to clear
drain.
TOUCHLESS SENSOR ONLY
Wipe sensor window with a soft cloth and mild
detergent. Rinse with clear water and dry with a clean
soft cloth.
Dust and dirt can be removed from exterior surfaces
with mild household dish-washing detergent and warm
water. Wipe dry with a clean, soft cloth.
Part Number STH044 10/13 27
Preventative Maintenance Procedure
!
Caution
Ice machine cleaner is used to remove lime scale or
other mineral deposits. It is not used to remove algae
or slime. Refer to “Sanitizing Procedure” for removal of
algae and slime. To initiate a cleaning cycle using
Manitowoc’s Cleaning Technology use the following
procedure.
Step 1 To start a cleaning cycle, move the toggle
switch to the CLEAN position. Water will flow through
the water dump valve and down the drain.
Step 2 Remove the cover fro m the top of the ice
chute. Wait about one minute then add the proper
amount of Manitowoc Ice Machine Cleaner and reinstall cover.
Use only Manitowoc approved Ice Machine
Cleaner part number 000000084. It is a violation
of Federal law to use these solutions in a ma nner
inconsistent with their labeling. Read and
understand all labels printed on bottles before
use.
Model
RNS012 RNS020 2 ounces (60 ml)
Amount of Cleaner
Part Number 000000084
28 Part Number STH044 10/13
ICE
WATER
ICE /
WATER
ADD SOLUTION HERE
Step 3 The ice machine will automatically time out a
series of flush and rinse cycles, and then stops. This
entire cycle lasts approximately 30 minutes.
NOTE: Periodic cleaning must be performed on
adjacent surface areas not contacted by the water
distribution system.
NOTE: The ice machine may be set to start and finish
a cleaning procedure, and then automatically start ice
making again.
A. After cleaner is added move the switch from
CLEAN to ICE position.
B. When the cleaning cycle is complete ice
making will start automatically.
Part Number STH044 10/13 29
Changing toggle switch position during clean
cycle:
1. Less than 60 seconds into Clean cycle - The
Clean cycle will end when the toggle switch is
moved to the OFF position.
2. More than 60 seconds into Clean cycle - The ice
machine will complete the clean cycle. Toggle
switch position will determine the next cycle after
the Clean cycle is completed.
• CLEAN POSITION - The ice machine will wait for
a change in toggle switch position.
• OFF POSITION - The ice machine will wait for a
change in toggle switch position.
• ICE POSITION - The ice machine will start making
ice automatically.
3. To abort the clean cycle move the toggle switch
from CLEAN to OFF to CLEAN and back to OFF
within a 15 second time period.
Manitowoc recommends disassembling, cleaning and
sanitizing the ice machine and dispenser every six
months.
30 Part Number STH044 10/13
Heavily Scaled Cleaning Procedure
Ice machines that are heavily scaled or have not been
cleaned on a regular basis will need to run this
Procedure. Failure to do so may result in binding of the
auger as the lime scale releases from the auger and
evaporator barrel.
Step 1 Remove panels and set the ICE/OFF/CLEAN
toggle switch to the OFF position.
Step 2 Remove all ice from the bin.
Step 3 Turn off the water supply to the ice machine.
Step 4 Place ICE/OFF/CLEAN toggle switch in the
CLEAN position. The dump valve will open and drain
the water from the evaporator and reservoir.
Step 5 Wait approximately 30 seconds (or until the
evaporator is drained) and place the toggle switch in
the OFF position.
Step 6 Refer to chart and add the correct amount of
cleaner for your model ice machine.
Model
RNS012 RNS020 16 ounces (473 ml)
Amount of Cleaner
Part Number 000000084
Part Number STH044 10/13 31
Step 1 Turn on the water supply to the ice machine.
Important
ICE
WATER
ICE /
WATER
ADD SOLUTION HERE
Leave the cleaner/water solution in the
evaporator for a minimum of 4 hours.
Step 2 Move the toggle switch to the ICE position.
The compressor will energize and produce ice with the
cleaning solution. Continue the freeze cycle for 15
minutes.
Step 3 Move the toggle switch to the OFF position,
then follow the standard cleaning and sanitizing
procedures.
32 Part Number STH044 10/13
Cleaning And Sanitizing Procedure
!
Caution
Ice machines that are heavily scaled or have not been
cleaned on a regular basis will need to run the Heavily
Scaled Cleaning Procedure before this one. Failure to
do so may result in binding of the auger as the lime
scale releases from the auger and evaporator barrel.
Ice machine cleaner is used to remove lime scale or
other mineral deposits. Ice machine sanitizer is used
to remove algae or slim e.
Step 1 Remove panels and set the ICE/OFF/CLEAN
toggle switch to the OFF position.
Step 2 Turn off the water supply to the ice machine.
Step 3 Remove all ice from the bin.
Step 4 Place ICE/OFF/CLEAN toggle switch in the
CLEAN position. The dump valve will open and drain
the water from the evaporator and reservoir.
Step 5 Wait approximately 30 seconds (or until the
evaporator is drained) and place the toggle switch in
the OFF position.
Use only Manitowoc approved Ice Machine
Cleaner part number 000000084. It is a violation
of Federal law to use these solutions in a manner
inconsistent with their labeling. Read and
understand all labels printed on bottles before
use.
Part Number STH044 10/13 33
Step 6 Refer to chart and premix the correct solution
of cleaner and cool water for your model ice machine.
Amount of
Model
RNS012 RNS020 2 oz (60 ml) 32 oz (1 liter)
Cleaner
Part Number
000000084
Amount of
Water
Step 7 Remove the top cover from the ice chute and
pour the cleaner/water solution into the evaporator.
Add the entire amount of premixed solution (excess
solution will exit through the overflow tube in the water
reservoir).
Step 8 Replace the ice chute cover and allow the ice
machine to stand for 30 minutes.
Step 9 Turn on the water supply to the ice machine.
Step 10 Move the toggle switch to the ICE position.
The compressor will energize and produce ice with the
cleaning solution.
Step 11 The ice machine will freeze and discharge
the cleaning solution into the bin. Allow the cycle to run
for 15 minutes.
Step 12 Place the toggle switch in the OFF position
and discard all ice produced during the cleaning
process.
Step 13 Turn off the water supply to the ice machine.
Step 14 Place ICE/OFF/CLEAN toggle switch in the
CLEAN position. The dump valve will open and drain
the water from the evaporator and reservoir.
Step 15 Wait approximately 30 seconds (or until the
evaporator is drained) and place the toggle switch in
the OFF position.
Step 16 Refer to chart and premix the correct
solution of sanitizer and cool water for your model ice
machine.
Amount of Sanitizer
Model
Part Number
94-0565-3
Amount of Water
RNS012
RNS020
34 Part Number STH044 10/13
2 ounces (60 ml) 3 gallons (11.4L)
Step 17 Remove the top cover from the ice chute and
pour the sanitizer/water solution into the evaporator.
Add the entire amount of premixed solution (excess
solution will exit through the overflow tube in the water
reservoir).
Step 18 Replace the ice chute cover and allow the
ice machine to stand for 30 minutes.
Step 19 Turn on the water supply to the ice machine.
Step 20 Move the toggle switch to the ICE position.
The compressor will energize and produce ice with the
sanitizing solution.
Step 21 The ice machine will freeze and discharge
the sanitizing solution into the bin. Allow the cycle to
run for 15 minutes.
Step 22 Discard all ice produced during the sanitizing
process.
Step 23 Place the toggle switch in the CLEAN
position. The ice machine will automatically time out a
series of flush and rinse cycles, and then stops. This
entire cycle lasts approximately 30 minutes.
Step 24 Refer to Disassembly For Cleaning/
Sanitizing for your specific model and remove, clean
and sanitize all parts listed.
Part Number STH044 10/13 35
Component Disassembly For Cleaning
!
Warning
!
Warning
!
Caution
And Sanitizing
Disconnect electric power to the ice machine at the
electric switch box before proceeding.
Wear rubber gloves and safety goggles (and/or face
shield) when handling Ice Machine Cleaner or
Sanitizer.
Do not mix Cleaner and Sani tize r solutio ns toge ther.
It is a violation of Federal law to use these solutions
in a manner inconsistent with their labeling.
GENERAL INFORMATION
1. Turn off the water supply to the ice machine at the
water service valve, or disconnect water supply
line at float valve quick disconnect by depressing
stainless steel lever.
2. Remove the components you want to clean or
sanitize. See the pages specific to the model you
are working on for removal procedures.
3. Soak the removed parts to clean and sanitize.
Solution
Type
Cleaner 1 gal. (4 L) 16 oz. (500 ml) cleaner
Sanitizer 3 gal. (11 L) 2 oz. (60 ml) sanitizer
4. Use a soft-bristle brush or sponge (NOT a wire
brush) to carefully clean the parts.
5. Use the solution and a brush to clean all
disassembled components and the inside of the
bin.
Water Mixed With
6. Re-install the removed parts and turn on the water
and electrical supply .
36 Part Number STH044 10/13
Removal of Parts for Cleaning or Sanitizing
!
Warning
REMOVE
SCREWS
1. Turn off water supply to ice machine.
2. Place toggle switch in the clean position for 30
seconds to drain water from reservoir, then move
toggle switch to Off position.
3. Run dispenser to transfe r all ice from the bin to a
container.
Disconnect electric power to the ice machine at
the electric switch box before proceeding.
4. Disconnect electrical power to the ice machine.
5. Remove top cover.
A. Remove two screws.
B. Lift up on top cover to remove.
Part Number STH044 10/13 37
6. Remove front cover.
A. Lift up on front cover.
B. Pull forward to disengage keyhole slots.
7. Remove side panels.
38 Part Number STH044 10/13
8. Remove ice chute cover
LOOSEN SCREWS
A. Turn the two thumbscrews 1/4 turn.
B. Lift to remove cover.
Part Number STH044 10/13 39
9. Lift out ice damp er.
40 Part Number STH044 10/13
10. Lift out ice strainer ramp.
Part Number STH044 10/13 41
11. Turn ice wiper counterclockwise to remove.
42 Part Number STH044 10/13
12. Loosen ice chute hose clam p.
13. Disconnect ice chute drain.
14. Lift up on ice chute to remove. The ice chute must
be removed before the bin cover can be removed.
Part Number STH044 10/13 43
REMOVE SCREW
15. The ice chute can be cleaned in place. If complete
removal is desired use a phillips screwdriver to
remove the Hall Effect Switch assembly from the
ice chute.
44 Part Number STH044 10/13
16. Remove three thumbscrews, then remove bin
REMOVE THUMBSCREWS
cover.
Part Number STH044 10/13 45
17. Remove agitator bar.
RNS012 REMOVE THUMBSCREW
AND AGITATOR BAR
RNS020 REMOVE
AGITATOR,
AGITATOR BAR AND
ICE BREAKER
• RNS012 - Remove the thumbscrew and lift off.
• RNS020 - Unscrew the upright agitator bar.
NOTE: Bar must be reassembled by inserting front
edge into the paddle wheel, then lowering the back
edge (rounded 90 angle) to prevent water leakage into
the compressor compartment.
46 Part Number STH044 10/13
18. Remove ice deflector.
REMOVE
THUMBSCREW
A. Remove the two thumbscrews.
B. Lift the ice deflector out.
Part Number STH044 10/13 47
19. Remove ice dispensing wheel by lifting straight
out.
48 Part Number STH044 10/13
20. Water Reservoir Cover Removal
A. Push up on cover to snap off.
Part Number STH044 10/13 49
WATER DUMP VALVE
!
Warning
The water dump valve normally does not require
removal for cleaning. To determine if removal is
necessary:
1. Set the toggle switch to OFF.
2. Watch the water float valve. If the dump valve is
leaking the float will continue to add water in the
Off cycle.
• If the dump valve is leaking, remove, disassemble
and clean it.
• If the dump valve is not leaking, do not remove it.
Instead, follow the “Cleaning Procedure”.
Follow the procedure below to remove the dump
valve.
Disconnect the electric power to the ice machine
at the electric service switch box an d turn off the
water supply before proceeding.
1. Depres s and twist the coil 1/8 turn
counterclockwise.
2. Leaving the wires attached, lift the coil assembly
off the valve bo dy.
3. Remove the plunger, nylon gasket and diaphragm
from the valve body.
NOTE: At this point, the water dump valve can easily
be cleaned. If complete removal is desired, continue
with step 4.
50 Part Number STH044 10/13
4. Remove the tubing from the dump valve by
MOUNTING
BRACKET
NYLON
WASHER
SPRING
PLUNGER
DIAPHRAM
VALVE BODY
COIL
twisting the clamps off.
5. Remove the valve body from mounting bracket by
twisting counterclockwise.
.
Dump Valve Disassembly
Part Number STH044 10/13 51
CLEANING THE CONDENSER
!
Warning
!
Warning
Disconnect electric power to the ice machine at the
electric service switch before cleaning the
condenser. The condenser fins are sharp. Use care
when cleaning them.
A dirty condenser restricts airflow, resulting in
excessively high operating temperatures. This
reduces ice production and shortens component life.
Clean the condenser at least every six months. Follow
the steps below.
1. The washable foam filter on self-contained ice
machines is designed to catch dust, dirt, lint and
grease. This helps keep the condenser clean.
Clean the filter with a mild soap and water
solution.
2. Clean the outside of the condenser with a soft
brush or a vacuum with a brush attachment.
Clean from top to bottom, not side to side. Be
careful not to bend the condenser fins.
3. Shine a flashlight through the condenser to check
for dirt between the fins. If dirt remains:
A. Blow compressed air through the condenser
fins from the inside. Be careful not to bend
the fan blades.
B. Use a commercial condenser coil cleaner.
Follow the directions and cautions supplied
with the cleaner.
4. Straighten any bent condenser fins with a fin
comb.
5. Carefully wipe off the fan blades and motor with a
soft cloth. Do not bend the fan blades. If the fan
blades are excessively dirty, wash with warm,
soapy water and rinse thoroughly.
If you are cleaning the condenser fan blades with
water, cover the fan motor to prevent water damage.
52 Part Number STH044 10/13
Removal from Service/Winterization
!
Caution
GENERAL
S pecial precautions must be taken if the ice machine is
to be removed from service for an extended period of
time or exposed to ambient temperatures of 32°F
(0°C) or below.
If water is allowed to remain in the ice machine in
freezing temperatures, severe damage to some
components could result. Damage of this nature is
not covered by the warranty.
1. Disconnect the electric power at the circuit
breaker or the electric service switch.
2. Turn off the water supply.
3. Disconnect and drain the incoming ice-making
water line at the rear of the ice machine.
4. Disconnect drain tubing (from th e inlet to dump
valve) and drain water into container and discard.
5. Make sure water is not trapped in any of the water
or drain lines.
Part Number STH044 10/13 53
54 Part Number STH044 10/13
This Page Intentionally Left Blank
Troubleshooting
SafeGuard Feature
The ice machine will stop when conditions arise th at
would cause major component failure .
Standby Mode
The first time a failure occurs, the ice machine deenergizes and initiates a Standby Mode. The ice
machine will remain off for 60 minutes, then
automatically restart to see if the problem reoccurs.
During the Standby Mode the corresponding light
flashes continuously
speed). If the same failure keeps occurring, the ice
machine will initiate a SafeGuard Mode and remain off
until manually restarted.
SafeGuard Indicator Lights
During a SafeGuard Mode the corresponding light
(disch temp, water level or speed) will flash
continuously.
(disch temp, water level or
The SafeGuard will remain in memory for 48 hours of
ice making time. After 48 hours of ice making time the
SafeGuard will automatically be erased. If power is
interrupted during the 48 hours, the timing will resume
when power is applied to the ice machine.
Placing the toggle switch in the OFF position:
The corresponding light will flash continuously.
Placing the toggle switch in the ICE position:
The light will de-energize and a start-up sequence will
initiate. The corresponding light will flash anytime the
toggle switch is placed in the OFF position provided
48 hours of ice making time has not been exceeded.
Part Number STH044 10/13 55
Reset Procedure
1. Move the ICE/OFF/CLEAN toggle switch to OFF.
A. If a safeguard feature has stopped the ice
machine, it will restart after a short delay .
Proceed to Step 2.
B. If the ice machine does not restart, see “Ice
Machine Does Not Operate.”
2. Allow the ice machine to ru n to determine if the
condition is reoccurring.
A. If the ice machine continues to run, the
condition has corrected itself. Allow the ice
machine to continue running.
B. If the ice machine stops determine the
safeguard mode, then refer to the specific
safeguard for troubleshooting procedures.
56 Part Number STH044 10/13
SafeGuards
•No Water
• No Ice Production
NO WATER
The water sensing switch opens for more than 30
seconds.
Operation
When the float switch is open at initial start-up the ice
machine will wait for the switch to close before
starting.
During the freeze cycle if the water float opens for 30
seconds the ice machine will:
1. De-energize the compresso r and gearmotor.
2. The Water Ok light on the control board will deenergize.
3. A 15 minute delay is initiated.
The water Ok light will flash when the float switch
closes or when the toggle switch is placed in the OFF
position.
The ice machine will remain off until the 15 minute
delay period expires and the water float switch closes.
Part Number STH044 10/13 57
NO ICE PRODUCTION
The ice damper did not open and close at least once
every 90 seconds in the freeze cycle.
OPERATION
During the first 8 minutes of oper a ti o n :
The control board must see the ice damper open/close
at least once. This allows time for ice production to
start at all ambient temperatures
After the initial 8 minute period:
The control board must see the ice damper open/close
at least once every 90 seconds.
When the ice damper does not open/close within the
specified time the control board will:
1. De-energize the compressor an d gear motor.
2. HES #1 light on the control board will flash (the
light will not flash if the ice damper is open).
3. A 15 minute delay is initiated.
4. After the 15 minute delay the ice machine will:
A. Energize the dump valve for 30 seconds
B. Energize the gear motor
C. Wait until the water float valve closes and
then energize the compressor and fan motor.
5. If the ice damper fails to open/close at least once
in the initial 8 minute period, the control board will
initiate another safety shutdown. This sequence
will repeat until:
A. The ice machine restarts and operates
normally for 10 minutes.
B. The ice machine is unable to run normally
within 300 minutes of the initial shutdown.
If the ice machine does not run normally within 300
minutes of the initial shutdown, the control board will
lock out and require a manual reset.
The control board will flash the HES #1 light anytime
the toggle switch is placed in the off position for the
first 48 hours after the failure.
58 Part Number STH044 10/13
Reset Procedure
Move the ICE/OFF/CLEAN toggle switch from OF F to
ICE or disconnect and reapply power to the ice
machine.
Part Number STH044 10/13 59
Ice Machine Will Not Run Diagnostics
!
Warning
High (line) voltage is applied to the control board
(terminals #39 and #90) at all times. Removing
control board fuse or moving the toggle switch to
OFF will not remove the power supplied to the
control board.
The following sequence describes the normal start up
procedure for the ice machine when line voltage is
disconnected then reconnected to the ice machine.
1. Power is supplied to the control board.
2. The co ntrol board lights race (energize/deenergize in sequence) to indicate the ice machine
is in a 15 minute delay mode.
3. When the 15 minute delay ends the ice machine
starts. The following lights are energized:
• Nugget
• HES #1
• HES #2
• Water OK
The HES #1 light will de-energize and re- energize as
ice passes beneath the ice damper.
When the ice damper lifts approximately 45 degrees
HES #2 de-energizes and the ice machine shuts off
immediately on full bin. A 15 minute time delay is
initiated, which prevents the ice machine from
immediately restarting.
60 Part Number STH044 10/13
Part Number STH044 10/13 61
Power Supplied to
Ice M achine?
Plug In Ice Machine,
Rese t Breaker
NO
Ice Machine Will Not Run
IMPORTANT
A Five Minute Delay Initiates After The Problem Is
Corrected. This Delay Must Expire Before The Ice
Machine Will Start.
62 Part Number STH044 10/13
Power At
Terminals
#90 & #39?
Refer To High Pressure Cutout
Specifications.
NO
IMPORTANT
A Five Minute Delay Initiates After The Problem Is
Corrected. This Delay Must Expire Before The Ice
Machine Will Start.
YES
YES
Part Number STH044 10/13 63
Reservoir Full Of
Water?
NO
YES
Restore Water Supply
YES
IMPORTANT
A Five Minute Delay Initiates After The Problem Is
Corrected. This Delay Must Expire Before The Ice
Machine Will Start.
64 Part Number STH044 10/13
HES #1 Light
Energized?
Hes # 2 Light
Energized?
YES
YES
NO
NO
Refer To Hall
Effect Switch
Diagnostics
IMPORTANT
A Five Minute Delay Initiates After The Problem Is
Corrected. This Delay Must Expire Before The Ice
Machine Will Start.
Part Number STH044 10/13 65
5 Minute Delay
Expired?
Wait For Delay To Expire,
Then Refer To SafeGuards
YES
YES
No
IMPORTANT
A Five Minute Delay Initiates After The Problem Is
Corrected. This Delay Must Expire Before The Ice
Machine Will Start.
Refrigeration Diagnostics
BEFORE BEGINNING SERVICE
Ice machines may experience operational problems
only during certain times of the day or night. A
machine may function properly while it is being
serviced, but malfunctions later. Information provided
by the user can help the technician start in the right
direction, and may be a determining factor in the final
diagnosis.
Ask these questions before beginning service:
• When does the ice machine malfunction? (night,
day, all the time, only during the Freeze cycle, etc.)
• When do you notice low ice production? (one day
a week, every day, on weekends, etc.)
• Can you describe exactly what the ice machine
seems to be doing?
• Has anyone been working on the ice machine?
• During “store shutdown,” is the circuit breaker,
water supply or air temperature altered?
• Is there any reason why incoming water pressure
might rise or drop substantially?
INSTALLATION/VISUAL INSPECTION CHECKLIST
Possible Problem List Corrective Action List
Filter and/or condenser is
dirty.
Water filtration is plugged (if
used).
Water drain is not vented or
is improperly installed.
Clean the filter and
condenser.
Install a new water filter.
Run and vent drains
according to the installation
manual.
66 Part Number STH044 10/13
WATER SYSTEM CHECKLIST
A water-related problem could cause component
misdiagnosis.
Water system problems must be identified and
eliminated prior to replacing other components.
Possible Problem List Corrective Action List
Water area (evaporator) is
dirty.
Water inlet pressure not
between 20 and 80 psig.
Incoming water temperature
is not between 45°F (1.7°C)
and 90°F (32.2°C).
Water filtration is plugged (if
used).
Vent tube is not installed on
water outlet drain.
Hoses, fittings, etc., are
leaking water.
Water float valve is stuck
open or closed.
Dump valve is leaking.
Clean as needed.
Install a water regulator
valve or increase the water
pressure.
If too hot, check the hot
water line check valves in
other store equipment.
Install a new water filter.
See installation instructions.
Repair/replace as needed.
Clean/replace as needed.
Clean dump valve.
Ice machine will shut off on
Low Water SafeGuard.
Part Number STH044 10/13 67
ICE PRODUCTION/QUALITY CHECK
QUALITY CHECK
Ice quality will vary with ambient and water
temperatures, and is measured by the amount of
excess water in the ice. An easy test is to squeeze a
handful of ice. High quality ice releases only a small
amount of water. As ice quality drops, more water can
be removed.
Generally speaking, higher incoming water
temperature results in lower ice quality.
Lower water temperat ure results in higher ice qu a l it y.
ICE PRODUCTION CHECK
1. Run the ice machine a minimum of 10 minutes to
allow the system to stabilize.
2. Catch the ice in a non-perforated container for
7
minutes and 12 seconds or for more accuracy
14
minutes and 24 seconds.
3. Weigh the container and ice, then deduct the
weight of the container.
4. Convert ounces to pounds.
5. Example: 3 lbs. 12 oz. converts to 3.75 lbs.
6. (12 oz. ÷ 16 oz. =.75 lb.)
7. Determine the 24-hour ice production capacity.
• 7 minutes 12 seconds
• Multiply the total ice weight by 200.
• 14 minutes 24 seconds
• Multiply the total ice weight by 100.
Example:
1. Collected ice for 7 minutes 12 seconds
2. Total weight (minus container) = 3.75 lbs.
3. 3.75 lbs. x 200 = 750 lbs. of ice every 24 hours
4. Compare the capacity to the 24-hour ice
production chart for the model being tested.
5. Ice production checks that are within 10% of the
charted capacity are considered normal due to
variances in air and water temperatures. Actual
temperatures will seldom match the chart exactly.
68 Part Number STH044 10/13
ANALYZING DISCHARGE PRESSURE
1. Determine the ice machine operating conditions:
• Air temperature entering condenser
• Air temperature around ice machine
• Water temperature entering water reservoir
2. Refer to 24-Hour Ice Production/Refrigeration
Pressure Chart for ice machine being checked.
Use the operating conditions determined in step 1 to
find the published normal discharge pressures and
compare to actual discharge pressure readings.
3. Measure the actual discharge pressure.
4. Compare the actual discharge pre ssure (step 3)
with the published discharge pressure (step 2).
The discharge pressure is normal when the actual
pressure falls within the published pressure range for
the ice machine’s operating conditions.
Discharge Pressure High Checklist
Problem Cause
Improper
installation
Restricted
condenser
air flow
Improper
refrigerant
charge
Other Non-Manitowoc components in system
Refer to “Installation/Visual Inspection
Checklist.”
Dirty air filter
High inlet air temperature
Condenser discharge air recirculation
Dirty condenser fins
Defective fan motor
Overcharged
Non-condensible in system
Wrong type of refrigerant
High side refrigerant line/component
restricted (before mid-condenser)
Part Number STH044 10/13 69
Discharge Pressure Low Checklist
Problem Cause
Improper
installation
Improper
refrigerant
charge
Other
Refer to “Installation/Visual Inspection
Checklist.”
Undercharged
Wrong type of refrigerant
Low ambient temperature
Non-Manitowoc components in system
High side refrigerant lines/component
restricted (before mid-condenser)
Suction pressure is too low and affecting
discharge pressure. (Refer to “Suction
Pressure Low Checklist.”)
No water or insufficient pressure
Expansion valve incorrectly adjusted
Defective compressor
Moisture in refrigeration system
NOTE: Do not limit your diagnosis to only the items
listed in the checklists.
70 Part Number STH044 10/13
ANALYZING SUCTION PRESSURE
NOTE: Analyze discharge pressure before analyzing
suction pressure.
High or low discharge pressure may be causing high
or low suction pressure.
Suction Pressure High Checklist
Problem Cause
Improper
installation
Discharge
pressure
Improper
refrigerant
charge
Other
Refer to “Installation/Visual Inspection
Checklist.”
Discharge pressure is too high and is
affecting suction pressure. Refer to
“Discharge Pressure High Checklist.”
Overcharged
Wrong type of refrigerant
Non condensible in system
Dump valve leaking
Non-Manitowoc components in system
Expansion valve incorrectly adjusted
Defective compressor
Part Number STH044 10/13 71
Suction Pressure Low Checklist
Problem Cause
Improper
installation
Discharge
pressure
Improper
refrigerant
charge
Other Non-Manitowoc components in system
Refer to “Installation/Visual Inspection
Checklist.”
Discharge pressure is too low and is
affecting suction pressure. Refer to
“Discharge Pressure Low Checklist.”
Undercharged
Wrong type of refrigerant
Restricted/plugged liquid line drier
Restricted/plugged tubing in suction side of
refrigeration system
Expansion valve starving
No water or insufficient pressure
Moisture in refrigeration system
Dirty Evaporator
NOTE: Do not limit your diagnosis to only the items
listed in the checklists
72 Part Number STH044 10/13
Component Check Procedures
!
Warning
!
Warning
MAIN FUSE
FUNCTION
The control board fuse stops ice machine operation if
electrical components fail, causing high amp draw.
SPECIFICATIONS
The main fuse is 250 Volt, 10 amp, time delay.
High (line) voltage is applied to the control board at
all times. Removing the control board fuse or moving
the toggle switch to OFF will not remo ve the power
supplied to the control board.
CHECK PROCEDURE
1. Energized control board lights do not indicate a
good fuse.
Disconnect electrical power to the entire ice
machine before proceeding.
2. Remove the fuse. Check for continuity across the
fuse with an ohmmeter.
Reading Result
Open (OL) Replace fuse
Closed (O) Fuse is good
Part Number STH044 10/13 73
ICE/OFF/CLEAN TOGGLE SWITCH
FUNCTION
The switch is used to place the ice machine in ICE,
OFF or CLEAN mode of operation.
SPECIFICATIONS
Single-pole, double-throw switch. The switch is
connected into a varying low D.C. voltage circuit.
CHECK PROCEDURE
NOTE: Because of a wide variation in D.C. voltage, it
is not recommended that a voltmeter be used to check
toggle switch operation.
1. Inspect the toggle switch for correct wiring.
2. Isolate the toggle switch by disconnecting the
Molex connector.
3. Check continuity across the toggle switch
terminals. Note where the wire numbers are
connected to the switch terminals, or refer to the
wiring diagram to take proper readings.
Switch
Setting
ICE
CLEAN
OFF
Terminals Ohm Reading
1-6 Open
1-2 Closed
2-6 Open
1-6 Closed
1-2 Open
2-6 Open
1-6 Open
1-2 Open
2-6 Open
4. Replace the toggle switch if continuity readings do
not match all three switch settings.
74 Part Number STH044 10/13
FLOAT SWITCH
FUNCTION
The float switch prevents the ice machine from running
when the water level is below the control setpoint.
The float switch must be closed (float in up position)
before the ice machine will start, and must remained
closed throughout the freeze cycle.
SPECIFICATIONS
A mechanical liquid level sensor, that magnetically
operates a reed switch.
CHECK PROCEDURE
NOTE: The water float switch is connected to the
water reservoir cover. The reservoir cover must be in
place and water must be present in the reservoir to
close the switch. Verify water is supplied to the float
valve, the water inlet screen is clean, and the float and
float arm are free moving.
1. Disconnect power to the ice machine.
2. Disconnect the float switch from the control board
and connect an ohm meter to the switch wires.
3. Verify the switch is in the up position (reservoir full
of water), then check continuit.y.
Step 3 Check for Continuity
Reading Result
Closed The switch is working properly
Open Replace the switch
4. Remove cover from reservoir by lifting straight up.
Verify the switch opens as the float drops.
Part Number STH044 10/13 75
ICE DAMPER AND HALL EFFECT SWITCHES
Damper Door
FUNCTION
Opens and closes as ice passes from the ice chute to
the bin. A metal lever attached to the damper
interrupts the magnetic field sensed by the hall effect
switches as the damper opens and closes.
Hall Effect Switch #1 -
Operational Sensing
This switch will open and re-close in conjunction with
the ice damper as ice is discharged from the
evaporator. The control board must see this switch
open and close at least once every 90 seconds during
the freeze cycle.
Hall Effect Switch #2 -
Shut-Off and Restart
This switch also works in conjunction with the ice
damper . When the switch opens, the ice machine
stops immediately. The ice machine restarts when the
switch re-closes and the five minute delay period
expires.
FUNCTION TEST
Place toggle switch in OFF position. HES#1 and
HES#2 lights will energize. Move ice damper slowly to
open position.
• HES#1 light de-energizes, HES#2 remains
energized.
• HES#2 light de-energizes as damper continues to
open.
Move damper slowly to closed position HES#2
energizes, HES#1 remains de-energized.
HES#1 energizes as the damper continues to close.
76 Part Number STH044 10/13
Hall Effect Switch Diagnostics
All diagnostics must be performed with the ice damper
installed and in the closed position. The control board
lights will not indicate as described below with the ice
damper in the open position. The ice damper must
swing freely, if the damper is binding adjust/loosen
screws that hold the Hall Effect Switch Housing in
place.
SWITCH FAILS OPEN OR IS DISCONNECTED
HES#1
1. Reset line voltage to the ice machine
2. Wait 15 minutes for delay to expire.
3. HES#1 light energizes and ice machine starts.
4. When 15 minute delay period ends the ice
machine shuts off and flashes the HES#1 light.
HES#2
1. Reset line voltage to the ice machine.
2. Wait 15 minutes for delay to expire.
3. HES#2 light is energized and HES#1 light is deenergized.
4. Ice machine starts.
5. After 15 minutes the ice machine shuts off.
HES#1 is de-energized and HES#2 is energized.
Part Number STH044 10/13 77
SWITCH FAILS CLOSED
HES#1
1. Reset line voltage to the ice machine
2. Wait 15 minutes for delay to expire.
3. HES#1 light de-energized.
4. The ice machine starts, runs for 20 seconds, then
de-energizes.
5. HES#1 light is de-energized.
HES#2
1. Reset line voltage to the ice machine
2. Wait 15 minutes for delay to expire.
HES #2 is a three wire switch and can stop in three
separate failure modes.
• HES #1 is energized, HES #2 is de-energized, the
ice machine will not start.
• HES #1 and HES #2 lights are de-energized, the
ice machine will not start.
• HES #1 and HES #2 are energized. The ice
machine starts, immediately shuts off and starts
another 15 minute delay period (control board
lights race to indicate 15 minute delay period). The
ice machine will repeat the sequence until the
toggle switch is moved to OFF or power is
disconnected to the ice machine.
In all failure modes disconnecting HES #2 from the
control board will result in Switch Fails Open or is
Disconnected symptoms (see previous page).
78 Part Number STH044 10/13
SELECTOR SWITCH
FUNCTION
Selects product dispensed. Ice, Water or Ice and
Water.
CHECK
DISPENSE LEVER ACTIVATED
Step 1 Verify line voltage is present at control board
wires #20 & #22. Note - If a blue indicator light is
energized on the touch pad the control board has line
voltage.
Step 2 Depress each selection on the touch pad.
• 1 or more LED’s do not energize/de-energize
when a selection is pressed - Replace touch pad
• Each touch pad LED energizes/de-energizes as
selections are pressed - Go to next step
Step 3 Isolate and ohm the ice dispense switch
(Wires #59 & #60). The selector switch closes when
depressed and opens when released.
• Switch does not close/open when the switch is
pressed/released - Replace switch
• Switch closes/opens as the switch is pressed/
released - Go to next step
Step 4 Reconnect dispense switch and test both
relays for line voltage:
• Wires #58 & #54 = Ice Dispense Motor
• Wires #52 & #56 = Water Solenoid
• Replace wiring, component or control board as
required.
Part Number STH044 10/13 79
TOUCHLESS SENSOR ACTIVATED
Step 1 V erify line voltage is present at control board
wires #20 & #22. Note - If a blue indicator light is
energized on the touch pad the control board has line
voltage.
Step 2 Depress each selection on the touch pad.
• 1 or more LED’s do not energize/de-energize
when a selection is pressed - Replace touch pad
• Each touch pad LED energizes/de-energizes as
selections are pressed - Go to next step
Step 3 Verify line voltage is supplied to touchless
sensing control board at wires #49 & #50.
Will Not Dispense
• Disconnect wires from C (common) and NO
(normally open) terminals on the sensor control
board.
• Use an ohm meter to verify the switch is opening
and closing. Place hand in front of sensor, if the
sensor activates and closes the switch the sensor
is working correctly.
• If the sensor does not activate the switch,
disconnect the sensor wire from the sensor control
board. Short +5 and SIG.
• If the contacts close replace the sensor.
• If the contacts remain open replace the sensor
control board.
80 Part Number STH044 10/13
Will Not Stop Dispensing
• Disconnect sensor plug from sensor control board.
• If the dispensing stops, replace the sensor
• If the dispensing continues disconnect wires
#59 & #60 from the control board
• Check resistance across control board contacts
• Closed = Replace the touchless sensing control
board
• Open = Dispense control board is not
functioning correctly, check control board relays
Replace the selector switch if ohm readings do not
match all three switch settings.
Part Number STH044 10/13 81
DISPENSE SWITCH
FUNCTION
Supplies power to the product selector switch when
activation lever is depressed.
CHECK
1. Inspect the selector switch for correct wiring.
2. Isolate the switch by disconnecting all wires from
the switch.
3. Check across the sw itch terminals with an ohm
meter.
Activation Lever Position Resistance Reading
Depressed Closed
Released Open
Replace the selector switch if ohm readings do not
match.
82 Part Number STH044 10/13
TOUCHLESS SENSOR
FUNCTION
Supplies power to the product selector switch when
container activates sensor.
CHECK
Container must be within an inch of sensor to activate.
Will Not Dispense
1. Verify power is supplied to the ice machine. When
the toggle switch is in ICE position the blue LED
light will be on.
2. Disconnect wires from C (common) and NO
(normally open) terminals on the sensor control
board.
3. Use an ohm meter to verify the switch is opening
and closing. Place hand in front of sensor, if the
sensor activates and closes the switch the sensor
is working correctly.
4. If the sensor does not activate disconnect the
sensor wire from the sensor control board. Short
+5 and SIG.
• If the contacts close replace the sensor.
• If the contacts remain open replace the sensor
control board.
Will Not Stop Dispensing
1. Disconnect sensor plug from sensor control
board.
• If the dispensing stops, replace the sensor.
2. If the dispensing continues disconnect wires 22 &
59/60 from the control board.
3. Check resistance across control board contacts.
• Closed = Replace the sensor control board
• Open = Refer to selector switch diagnostics.
Part Number STH044 10/13 83
HIGH PRESSURE CUTOUT CONTROL
!
Warning
FUNCTION
Stops the ice machine if subjected to excessive high-
side pressure.
The HPCO control is normally closed, and opens on a
rise in discharge pressure.
Specifications
Cut-Out Cut-In
450 psig ±10
(3103 kPa ±69)
31 bar ±.69
(Must be below 300 psig
(2068 kPa 20.68 bar) to reset.)
Automatic Reset
CHECK PROCEDURE
1. Set ICE/OFF/CLEAN switch to OFF, (Manual
reset HPCO reset if tripped).
2. Disconnect main power supply to the ice
machine.
3. Connect manifold gauges to the access valves.
4. Hook voltmeter in parallel across the HPCO,
leaving wires attached.
5. Reconnect main power supply to the ice machine.
6. Set ICE/OFF/CLEAN switch to ICE.
7. No water or air flowing through the condenser will
cause the HPCO control to open because of
excessive pressure. Watch the pressure gauge
and record the cut-out pressure.
If discharge pressure exceeds 460 psig (3172 kPa
31.72 bar) and the HPCO control does not cut out,
set ICE/OFF/CLEAN switch to OFF to stop ice
machine operation.
Replace the HPCO control if it:
8. Will not reset [below 300 psig (2068 kPa 20.68
bar).
9. Does not ope n at the specified cut-out point.
84 Part Number STH044 10/13
FAN CYCLE CONTROL
FUNCTION
Energizes and de-energizes the condenser fan motor.
The fan cycle control closes on an increase, and
opens on a decrease in discharge pressure.
Specifications
Cut-In (Close) Cut-Out (Open)
250 psig ±5 200 psig ±5
CHECK PROCEDURE
1. Verify fan motor windings are not open or
grounded, and fan spins freely.
2. Connect manifold gauge set to ice machine.
3. Hook voltmeter in parallel across the fan cycle
control, leaving wires attached.
4. Refer to chart below.
FCC Setpoint:
Above Cut-In 0 Volts Running
Below Cut-Out Line Voltage Off
Reading Should
Be:
Fan
Should Be:
Part Number STH044 10/13 85
LOW PRESSURE CUTOUT (LPCO) CONTROL
FUNCTION
Stops the ice machine if the low side pressure is too
low. The LPCO control is closed at pressures above
setpoint and opens at pressures below setpoint.
Specifications
Cut-Out Cut-In
Current Production &
Replacement Part
17 psig ±5 35 psig ±7
CHECK PROCEDURE
1. Connect manifold gauge set to suction access
valve.
2. Disconnect wires from low pressure switch and
connect ohm meter across LPCO terminals.
Replace the LPCO control if it:
1. Is not closed at the specifie d setpoint.
2. Does not ope n at the speci fied setpoint.
86 Part Number STH044 10/13
COMPRESSOR ELECTRICAL DIAGNOSTICS
The compressor does not start or will trip repeatedly
on overload.
Check Resistance (Ohm) Values
NOTE: Compressor windings can have very low ohm
values. Use a properly calibrated meter.
Perform the resistance test after the compressor
cools. The compressor dome should be cool enough
to touch (below 120°F/49°C) to assure that the
overload is closed and the resistance readings will be
accurate.
SINGLE PHASE COMPRESSORS
1. Disconnect power then remove the wires from the
compressor terminals.
2. The resistance values between C and S and
between C and R, when added together, should
equal the resistance value between S and R.
3. If the overload is open, there will be a resistance
reading between S and R, and open readings
between C and S and between C and R. Allow the
compressor to cool, then check the readings
again.
Check Motor Windings to Ground
Check continuity between all three terminals and the
compressor shell or copper refrigeration line. Scrape
metal surface to get good contact. If continuity is
present, the compressor windings are grounded and
the compressor should be replaced.
Part Number STH044 10/13 87
Compressor Drawing Locked Rotor
To determine if the compressor is seized, check the
amp draw while the compressor is trying to start.
The two likely causes of this are a defective starting
component and a mechanically seized compressor.
To determine which you have:
1. Install gauge on high and low side.
2. Try to start the compressor.
3. Watch the pressure s clo se l y.
A. If the pressures do not move, the compressor
is seized. Replace the compressor.
B. If the pressures move, the compressor is
turning slowly and is not seized. Check the
capacitors and relay.
COMPRESSOR DRAWING HIGH AMPS
The continuous amperage draw on start-up should not
be near the maximum fuse size indicated on the serial
tag.
Diagnosing Capacitors
• If the compressor attempts to start, or hums and
trips the over lo a d protector, check the starting
components before replacing the compressor.
• Visual evidence of capacitor failure can include a
bulged terminal end or a ruptured membrane. Do
not assume a capacitor is good if no visual
evidence is present.
• A good test is to install a known good substitute
capacitor.
• Use a capacitor tester when checking a suspect
capacitor. Clip the bleed resistor off the capacitor
terminals before testing.
88 Part Number STH044 10/13
DIAGNOSING START COMPONENTS
If the compressor attempts to start, or hums and trips
the overload protector, check the start components
before replacing the compressor.
Capacitor
Visual evidence of capacitor failure can include a
bulged terminal end or a ruptured membrane. Do not
assume a capacitor is good if no visual evidence is
present. A good test is to install a known good
substitute capacitor. Use a capacitor tester when
checking a suspect capacitor. Clip the bleed resistor
off the capacitor terminals before testing.
Relay
The relay has a set of contacts that connect and
disconnect the start capacitor from the compressor
start winding. The contacts on the relay are normally
closed (start capacitor in series with the start winding).
The relay senses the voltage generated by the start
winding and opens the co ntacts as the compress or
motor starts. The contacts remain open until the
compressor is de-energized.
Part Number STH044 10/13 89
Relay Operation Check
!
Warning
Disconnect electrical power to the ice machine
before proceeding.
1. Disconnect wires from relay terminals.
2. Verify the contacts are closed.
Measure the resistance between terminals 1 and
2. No continuity indicates open contacts. Replace
the relay.
3. Check the relay coil .
Measure the resistance between terminals 2 and
5. No resistance indicates an open coil. Replace
the relay.
4. Move toggle switch to th e ICE position.
5. The compressor start winding should energize for
less than 1 second. Continued high amperage
draw could indicate:
• Low incoming power supply.
(Check voltage at compressor start-up when load
is greatest.)
• Defective relay.
• Defective capacitor.
• Defective compressor.
6. Verify voltage and replace all start components.
7. If all of the previous tests are satisfactory and the
compressor will not operate or continue to
operate, replace the compressor.
90 Part Number STH044 10/13
Refrigerant Recovery/Evacuation
Important
Important
NORMAL SELF-CONTAINED PROCEDURES
Do not purge refrigerant to the atmosphere. Capture
refrigerant using recovery equipment. Follow the
manufacturer’s recommendations.
Manitowoc Ice assumes no responsibility for the use
of contaminated refrigerant. Damage resulting from
the use of contaminated refrigerant is the sole
responsibility of the servicing company .
Replace the liquid line drier before evacuating and
recharging. Use only a Manitowoc (OEM) li quid line
filter-drier to prevent voiding the warranty.
CONNECTIONS
Manifold gauge sets must utilize low loss fittings to
comply with U.S. Government rules and regulations.
Make these connections:
• Suction side of the compressor through the suction
service valve.
• Discharge side of the compressor through the
discharge service valve.
Part Number STH044 10/13 91
Recovery/Evacuation Procedures
RECOVERY/EVACUATION CONNECTIONS
OPEN
OPEN
VACUUM PUMP/
RECOVERY UNIT
CLOSED
SCALE
REFRIGERANT
CYLINDER
OPEN
LOW SIDE
ACCESS
VALVE
HIGH SIDE
ACCESS
VALVE
1. Place the toggle switch in the OFF position.
2. Install manifold gauge set, scale, and recovery
unit or two-stage vacuum pump.
3. Perform recovery or evacuation:
A. Recovery: Operate the rec overy un i t as
directed by the manufacturer’s instructions .
B. Evacuation prior to recharging: Pull the
system down to 250 microns. Then allow the
pump to run for an additional half hour. Turn
off the pump and perform a standing vacuum
leak check.
NOTE: Check for leaks using an electronic leak
detector after charging the ice machine.
4. Follow the Charging Procedures on the next
page.
92 Part Number STH044 10/13
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