Kendro UPRIGHT CHEST FREEZER User manual
-40 C and –85 C
ULTRA LOW-TEMPERATURE
UPRIGHT & CHEST FREEZER
(1993 - PRESENT)
SERVICE MANUAL
November 2002
Kendro Laboratory Products
All rights reserved 301903H13
Copyright 2002
Kendro Laboratory Products All rights reserved.
No part of this publication may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any
language in any form by any means without the written permission of Kendro Laboratory Products Training Department.
TABLE OF CONTENTS
SECTION 100 -- GENERAL INFORMATION
MODEL
MODEL
NUMBER AND SERIAL NUMBER IDENTIFICATION ..............................................................................100.1
TYPES .............................................................................................................................................................100.2
REFRIGERATION SYSTEM ........................................................................................................................................100.5
SECTION 200 -- SAFETY
ELECTRICAL
SAFETY ................................................................................................................................................200.1
REFRIGERANT SAFETY ............................................................................................................................................. 200.2
SECTION 300 - TECHNICAL INFORMATION
FEATURES ....................................................................................................................................................................300.1
A
DDITIONAL ULTIMA II FEATURES. ................................................................................................................................. 300.2
RECOMMENDED
P
REVENTIVE MAINTENANCE............................................................................................................................................300.4
TOOL LIST..................................................................................................................................... 300.3
SECTION 400 - MAINTENANCE AND REPAIR PROCEDURES
C
ABINET
LEVELING
DEFROSTING
OF A CHEST OR UPRIGHT FREEZER....................................................................................................400.1
A CHEST OR UPRIGHT FREEZER ....................................................................................................400.2
DOOR ADJUSTMENT OF AN UPRIGHT FREEZER..................................................................................................400.3
LID ADJUSTMENT OF A CHEST FREEZER..............................................................................................................400.4
UPRIGHT
FREEZER GASKET REPLACEMENT .......................................................................................................400.5
CHEST FREEZER GASKET REPLACEMENT............................................................................................................400.6
HANDLE REPLACEMENT FOR CHEST FREEZER...................................................................................................400.8
UPRIGHT
FREEZER CAM LATCH DOOR LOCK REPLACEMENT........................................................................400.9
CHEST FREEZER LID LOCK REPLACEMENT .......................................................................................................400.11
UPRIGHT FREEZER EXTERIOR DOOR HINGE REPLACEMENT........................................................................400.12
CHEST
FREEZER HINGE REPLACEMENT.............................................................................................................400.13
UPRIGHT FREEZER INTERIOR DOOR REPLACEMENT......................................................................................400.14
DOOR ASSEMBLY REPLACEMENT AND SEAL CHECK ON UPRIGHT UNITS................................................400.15
LID
ASSEMBLY REPLACEMENT AND SEAL CHECK ON CHEST UNITS .........................................................400.16
BREAKER STRIP REPLACEMENT ON A CHEST OR UPRIGHT FREEZER.........................................................400.17
CHEST
LEVELING
AND UPRIGHT FREEZER FILTER REPLACEMENT.................................................................................400.18
LEG REPLACEMENT.............................................................................................................................400.19
CASTER REPLACEMENT .........................................................................................................................................400.20
E
LECTRICAL / ELECTRONIC
COMPRESSOR
CONTROL
CAPACITOR
RELAY EVALUATION AND REPLACEMENT ............................................................................400.21
RELAY EVALUATION AND REPLACEMENT.................................................................................... 400.23
EVALUATION AND REPLACEMENT ..............................................................................................400.25
VOLTAGE BOOST RELAY EVALUATION AND REPLACEMENT ......................................................................400.27
SURGE
SURGE
SUPPRESSER EVALUATION & REPLACEMENT (UPRIGHT FREEZER)..............................................400.29
SUPPRESSER EVALUATION & REPLACEMENT (CHEST FREEZER) .................................................. 400.31
“MICRO” CONTROL PRINTED CIRCUIT BOARD EVALUATION & REPLACEMENT .....................................400.33
“MICRO”
“MICRO”
POWER SUPPLY PCB EVALUATION AND REPLACEMENT..............................................................400.36
DISPLAY PCB ............................................................................................................................................400.38
CONTROL DISPLAY HARNESS REPLACEMENT (UPRIGHT AND CHEST) ...........................................................................400.41
HEAT
EXCHANGER SENSOR REPLACEMENT (UPRIGHTS) ..............................................................................400.44
HEAT
EXCHANGER SENSOR REPLACEMENT (CHESTS) ...................................................................................400.45
CABINET
AMBIENT/CONDENSER
AMBIENT/CONDENSER
CONTROL / DISPLAY SENSOR EVALUATION & REPLACEMENT.................................................. 400.46
SENSOR EVALUATION AND REPLACEMENT (UPRIGHT) .....................................400.48
SENSOR EVALUATION AND REPLACEMENT (CHESTS)........................................400.49
TEMPERATURE RECORDER REPLACEMENT......................................................................................................400.50
TEMPERATURE RECORDER SENSOR REPLACEMENT...................................................................................... 400.52
ALARM
BATTERY EVALUATION AND REPLACEMENT ...................................................................................400.54
VOLTAGE BOOST TRANSFORMER EVALUATION AND REPLACEMENT ...................................................... 400.56
EVALUATION AND REPLACEMENT OF FAN MOTOR AND BLADE ................................................................400.58
S
OLID STATE CONTROL BOARD REPLACEMENT FOR VALUE-FEATURED FREEZERS....................................................... 400.59
VOLTAGE BOOST CONTROL PCB ..........................................................................................................................400.60
INTERSTAGE
TEMPERATURE
INTERCONNECT (“D62”) PCB.........................................................................................................400.61
CALIBRATION PROCEDURE .....................................................................................................400.63
PRESSURE EQUALIZATION PORT HEATER REPLACEMENT PROCEDURE...................................................400.64
R
EFRIGERATION
FIRST
STAGE SYSTEM CLEAN-UP/FLUSHING .................................................................................................... 400.66
SECOND STAGE SYSTEM CLEAN-UP/FLUSHING ............................................................................................... 400.69
FIRST
STAGE PRESSURE SWITCH EVALUATION AND REPLACEMENT........................................................400.72
SECOND
STAGE PRESSURE SWITCH EVALUATION AND REPLACEMENT...................................................400.75
FIRST STAGE COMPRESSOR REPLACEMENT ...............................................................................................................400.78
SECOND
AIR
STAGE COMPRESSOR REPLACEMENT ................................................................................................400.81
COOLED CONDENSER REPLACEMENT (CHESTS).......................................................................................400.84
AIR COOLED CONDENSER REPLACEMENT (UPRIGHTS).....................................................................................400.85
FIRST
AND SECOND STAGE REFRIGERATION SYSTEM EVACUATION..........................................................400.86
FIRST STAGE REFRIGERATION SYSTEM CHARGING..............................................................................................400.87
SECOND STAGE REFRIGERATION SYSTEM CHARGING ..................................................................................400.88
A
CCESSORIES AND OPTIONAL EQUIPMENT
LCO2
DOOR SAFETY SWITCH EVALUATION AND REPLACEMENT...............................................................400.90
LCO2 LID SAFETY SWITCH EVALUATION AND REPLACEMENT....................................................................400.91
LCO2
PRESSURE SWITCH ASSEMBLY EVALUATION AND REPLACEMENT ................................................400.92
LCO2 RUPTURE DISC EVALUATION AND REPLACEMENT..............................................................................400.94
LCO2 DISTRIBUTION TUBE EVALUATION AND REPLACEMENT ...................................................................400.95
LCO2
BACKUP SYSTEM TEMPERATURE CALIBRATION, BUILT-IN...............................................................400.96
LCO2 BACKUP SYSTEM TEMPERATURE CALIBRATION, FREE-STANDING.................................................400.97
INSTALLATION
OF CHEST FREEZER INVENTORY CONTROL RACK SYSTEM.............................................400.98
COBEX TEMPERATURE RECORDER ................................................................................................................................400.98
SECTION 500 - APPENDIX
T
ABLE 1 FAHRENHEIT / CELSIUS CONVERSION CHART...............................................................................................500.1
TABLE 2 100 OHM PLATINUM RTD TEMPERATURE / RESISTANCE CHART .................................................................500.2
TABLE 3 MODEL NUMBER CROSS-REFERENCE........................................................................................................... 500.3
T
ABLE 4 REFRIGERANT CHARGE, CHEST .................................................................................................................... 500.9
ABLE 5 REFRIGERANT CHARGE, UPRIGHT ..............................................................................................................500.11
T
T
ABLE 6 HARRIS CLASSIC™ REFRIGERANT CHARGE ............................................................................................... 500.13
T
ABLE 7 OIL CHARGE, UPRIGHT............................................................................................................................... 500.14
ABLE 8 OIL CHARGE, CHEST .................................................................................................................................. 500.14
T
TABLE 9 TEMP / MV FOR COMPRESSOR, CONDENSER & AMBIENT SENSORS ............................................................ 500.15
T
ABLE 10 PARTS LIST.................................................................................................................................................500.16
EAT EXCHANGE JUMPER, UPRIGHT AND CHEST FULL-FEATURED FREEZERS ............................................................. 500.17
H
FIGURE 500-1 CASCADE REFRIGERATION ASSEMBLY, UPRIGHT FREEZER .............................................................500.18
F
IGURE 500-2 CASCADE REFRIGERATION ASSEMBLY, CHEST FREEZER.................................................................500.19
FIGURE 500-3 ELECTRICAL DECK, UPRIGHT FULL-FEATURED FREEZER ................................................................500.20
IGURE 500-4 ELECTRICAL DECK, CHEST FULL-FEATURED FREEZER.................................................................... 500.21
F
F
IGURE 500-5 ELECTRICAL DECK, UPRIGHT VALUE-FEATURED FREEZER .............................................................500.22
IGURE 500-6 ELECTRICAL DECK, CHEST VALUE-FEATURED FREEZER................................................................. 500.23
F
F
IGURE 500-7 ELECTRICAL DIAGRAM, UPRIGHT AND CHEST FULL-FEATURED FREEZERS .................................... 500.24
FIGURE 500-8 ELECTRICAL DIAGRAM, UPRIGHT AND CHEST VALUE-FEATURED FREEZERS..................................500.25
INTRODUCTION
Ultra Low Temperature -85C/-40C Upright and -85C/-40C Chest freezers are base units, manufactured wholly at the Kendro
Laboratory Products facility in Asheville, NC. Kendro Laboratory Products is a division of SPX Corporation
The Upright units come in 13, 17, 21, 25 and 32 cubic foot sizes. The Chest units come in 1, 3, 5, 7, 10, 14, 17, and 20 cubic
foot sizes.
The purpose of this manual is to provide procedures developed to assist the field refrigeration technician in troubleshooting
and repairing certain conditions.
Product Specifications Are Subject To Change Without Written Notice.
Progressive product changes will be entered into the service manual as it is revised. The
manual is intended as an aid to persons qualified in the service of applicable equipment. It
is not intended to teach unqualified persons on applicable equipment all procedures necessary to make repairs.
SECTION 100 -- GENERAL INFORMATION
MODEL NUMBER AND SERIAL NUMBER IDENTIFICATION
Model numbers are important to know, since they
identify the unit as to what group it is in. This number does not identify a unit specifically; but rather,
indicates to what group this unit belongs.
The serial number is a unique number in that it identifies the unit as a specific unit. No other unit has that
same number.
DATA LABEL LOCATION
The model and serial numbers of your refrigerator are
printed on a plastic identification label and mounted
on the unit. This label is commonly referred to as the
data label because the most important information
concerning your unit can be gathered from the model
number and the serial number identification.
The data label is mounted on the outside of the cabinet. It can be found by looking on the upper left-hand
side of the unit, near the front of the cabinet. Some
older models may have a metal plate located on the
outer, lower left hand side of the unit.
DATA LABEL INFORMATION
Much information can be gathered from a data label.
The model and serial numbers can be found there, as
well as information such as type of refrigerant, voltage rating, frequency rating, and current rating, are
also normally found on a data label.
Upright Freezers
Figure 100-1
Data Label
Chest Freezers
Figure 100-2
Dataplate Location
General Information 100.1
MODEL TYPES
New picture goes here
3
17 ft
, 21 ft3 25, & 32 ft3 Upright
Figure 100-3
Figure 100-4
3
1ft
Countertop
Figure 100-5
3
10 ft
Chest
General Information 100.2
MODEL TYPES (CONT.)
Figure 100-6
3
14ft
Chest
Figure 100-7
3
5 ft
Chest
Figure 100-8
3
7ft
Chest
General Information 100.3
MODEL TYPES (CONT.)
(Optional Recorder shown)
New picture goes here
Figure 100-9
3
13 ft
Upright
Figure 100-10
5ft
3
Chest
Figure 100-11
3
7ft
Chest
(Optional Recorder shown)
General Information 100.4
REFRIGERATION SYSTEM
Figure 100-12
Two Stage Cascade Refrigeration System
General Information 100.5
REFRIGERATION SYSTEM (CONT.)
All of the units covered by this service manual use a
one or two stage refrigeration system for cooling the
unit. The fundamental components of a refrigeration
system are the compressor, condenser, drier-strainer,
metering device (normally a capillary tube or txv),
and the evaporator. Every refrigeration system operates using some configuration of most, if not all of
these components.
The following is a description of the components of
the refrigeration cycle.
COMPRESSOR
The function of the compressor is to take the relatively cool gaseous refrigerant at its suction, and raise
the pressure and temperature of the refrigerant by
compressing it. Remember that any time a gas is
compressed, the temperature and the pressure are
increased. Since liquids such as water are incompressible, it very important that all of the refrigerant
be in a gaseous state before it reaches the compressor.
The function of the compressor is to add useful work
energy to the refrigerant. The size and ratings of the
compressors depends upon the application and size of
the system.
Add picture of Copeland Semi
Legaci
Figure 100-13
TM
Compressor
General Information 100.6
REFRIGERATION SYSTEM (CONT.)
CONDENSER
The purpose of the condenser is to take the hot gaseous refrigerant, remove latent heat of condensation,
and cause it to condense. This is needed in order to
extract energy from the refrigeration cycle. The reason the energy needs to be extracted is so that when
the refrigerant reaches the evaporator this energy can
be “put back in” which is where the cooling action
for the refrigerator and/or freezer takes place.
DRIER-STRAINER
As the condensed (liquid) refrigerant leaves the condenser, it passes through the drier-strainer, which
removes any moisture (except the liquid refrigerant)
or impurities before passing through the metering
device. It is important that a “molecular sieve dryer”
or other high quality dryer be used. This component
serves two purposes:
1. It prevents moisture, such as water, from staying
entrained in the refrigerant and possibly doing
damage to the compressor or other components in
the refrigeration cycle.
2. It prevents any foreign material from becoming
lodged in the metering device and decreasing the
efficiency of the cycle.
Figure 100-14
Forced Air Condenser
Figure 100-15
Typical Drier-Strainer
General Information 100.7
REFRIGERATION SYSTEM (CONT.)
CAPILLARY TUBE
The capillary tube is simply a length of tubing attached to the outlet tubing somewhere downstream of
the drier-strainer and the inlet of the evaporator. The
diameter and length of the tube depends on the application of the system involved and the capacity of that
system, and are calibrated to meter the right amount
of refrigerant required for that particular model. A
predetermined length of the capillary tube is soldered
along the exterior of the suction line, forming a heat
exchanger which helps to cool the liquid refrigerant
in the capillary tube and heat the refrigerant in the
compressor suction line. The capillary tube then connects to the evaporator where the tubing expands
back to its original size.
EVAPORATOR
As the refrigerant passes through the evaporator, it is
changed from a liquid to a vapor. Since the pressure
of the refrigerant is at a slightly lower pressure and
with the addition of heat, from the internal compartment of the refrigerator, the liquids temperature is
raised above the boiling point for that refrigerant and
the change of phase from a liquid to vapor takes
place. All of the liquid should have been changed to a
vapor at the outlet of the evaporator, ensuring that
only gaseous refrigerant is sent to the compressor.
Suction Line
Immediately upon leaving the evaporator, the refrigerant must pass through the accumulator. This device
is another defense in preventing liquid refrigerant
from reaching the compressor. It simply accumulates
any liquid that may still be in the line after it has left
the evaporator. These devices are normally used on
units with capillary tube type metering devices, but
may also be used with systems that have the thermostatic expansion valves. Remember, also, that a
portion of the outlet line of the evaporator leading
back to the compressor suction is connected to the
capillary tube or thermostatic expansion valve inlet
line, which also adds additional heat to the refrigerant
prior to reaching the compressor.
Figure 100-16
Capillary Tube
Figure 100-17
Evaporator
General Information 100.8
SECTION 200 -- SAFETY
Freezers are complex machines. Any attempt to repair a freezer should be done with caution. There can never be too
much said or written concerning safety in any area of work, especially when dealing with electricity and refrigerants.
Safety should be every persons concern and is every person’s responsibility. Your personal safety begins with
knowledge of the equipment that you are working on. We are concerned with your safety; therefore, we have written
a few ideas and reminders of safety concerns while working on freezers.
ELECTRICAL SAFETY
1. Know the location of the freezer’s circuit breakers
or fuses. Ensure all breakers and/or fuses are
clearly marked for quick identification and reference.
2. Before servicing any freezer, unplug the power
cord. Do not perform any maintenance or remove
an access panel on an energized unit. None of the
repairs in this manual require the freezer to have
electrical power applied during maintenance.
3. Be careful when handling freezer access panels,
parts, or any components that may have sharp
edges that may cause damage to wiring and electrical connections, not to mention personal injury.
Always use the correct tool for a job and be sure
those tools are in good condition. Ensure that
tools to be used on electrical devices are well insulated, if applicable.
Never interfere with or bypass the operation of any
switch, component or feature of the unit. Interlocks, relays, and switches are designed with a
specific purpose and should, therefore, not be altered.
6. Use only approved replacement parts that are the
correct size, rating, and capacity as the original
part. If you have a question concerning replacement parts, call the Factory Technical Services
Department.
7. When replacing any component, be sure any green
ground wires are reconnected securely in their
original positions to avoid danger of shock or
short circuit.
8. Never interfere with or bypass the operation of
any switch, component or feature of the unit.
9. Before reconnecting the power supply, ensure
uninsulated wires or terminals are not touching
the cabinet
10. Never alter a power cord in order to make it fit
an electrical outlet.
11. Be sure and reference any applicable wiring diagram(s) when reconnecting and replacing
electrical components.
12. To avoid electrical shock, fire, and equipment
damage, ensure that any wires or terminals touching the cabinet are insulated before connecting the
power supply. Electrical wiring and all grounds
must be correctly reconnected and secured away
from sharp edges, components and moving parts.
All panels and covers should be reinstalled before
the freezer is plugged in.
13. Never alter a power cord in order to make it fit
an electrical outlet. The line cord must be plugged
into a grounded, three-prong receptacle. Never cut
or remove the third (ground) prong from the
power cord connector.
14. Never substitute ordinary wire for any internal
wiring of a freezer. The internal wiring of these
units carry a special rating due to the somewhat
high currents that they can be subjected to at
times. This heavy current load generates heat,
which can melt ordinary wire. It is vitally important that all connections are tight and secure.
15. Throughout this service manual, additional safety
precautions dealing with specific procedures may
be presented. This information should be carefully
read and observed.
Safety 200.1
REFRIGERANT SAFETY
1. The following is a list of the more common refrigerants that you will possibly be dealing with:
R290, R134a, R508b, and R404a.
CAUTION None of these refrigerants will
support life. All are classified as
asphyxiates.
2. The following are effects of over exposure:
light-headedness
giddiness
shortness of breath
unconsciousness
possibly death
Emergency and First Aid Procedures
Remove to fresh air
Call a physician
Do not give heart stimulating drugs such as epinephrine or similar drugs.
3. As all of the refrigerants listed have a vapor density of 3.00 or over 7.00, proper ventilation is
mandatory, especially in the low places where the
heavy vapor could collect.
4. Do not have open flames in this area. These refrigerants, when exposed to open flame, may
produce toxic compounds such as hydrogen chloride, hydrogen fluoride, and other acidic vapors
may be produced when these refrigerants are exposed to open flames.
5. Smoking should never take place around any of
the listed refrigerants. Deadly phosgene gas,
which can kill very quickly, is also one of the
compounds that these refrigerants can break down
into if they come in contact with a high enough
temperature flame.
6. Always use facial and eye protection, as well as
gloves when opening a system that has suffered a
“burn out”. The possibility of Hydrofluoric acid is
high.
7. Also use facial and eye protection and gloves
when handling liquid refrigerant.
8. The use of an air mask with an independent air
supply is recommended in areas of high concentrations and poor ventilation.
9. Avoid breathing all refrigerants if possible.
10. Treat all refrigerant cylinders with care. Store in
clean dry areas. Do not store at high temperatures.
11. The use of an air mask with an independent air
supply is recommended in areas of high concentrations and poor ventilation.
Safety 200.2
SECTION 300 - TECHNICAL INFORMATION
The information provided in this section is intended to give you as much information about the unit you will be performing maintenance on as possible. All of the numbers given are general in nature and may possibly be different
for the model that you are working on. The reason for this may be the possibility that the particular unit that you
may be working with is a special order unit, and is unique for its specific application.
The following information contains specifications
that apply to the Value, Elite and the Ultima II ultralow temperature freezers.
FEATURES
ELECTRONIC CONTROL & ALARM SYSTEM
Tamper-resistant touchpoint setpoint selection with
adjustable operating temperature (Ultima II)
Key operated switch for main power and alarm system.
Large digital temperature display, with a resolution to
o
1
C.
Built-in safety alarm system with automatic continuous-charge battery back-up.
Low battery indicator (Not All Models)
Touchpad alarm test (Not All Models)
Power failure or temperature deviation outside alarm
set limits triggers audible and visual warning.
(Not all Models)
MICROPROCESSOR CONTROL
Tamper-resistant touchpoint data entry with adjustable operating temperature (Not all Models)
Key operated switch for main power and alarm system.
Extra large digital temperature display, with a resolution to 1
o
C.
On-board AC power monitoring with digital read-out
of actual line voltage. (Not All Models)
Clean filter indicator advises user to clean condenser
intake filter. (Not all Models)
ALARM/MONITORING SYSTEM
Built-in safety alarm system with automatic continuous-charge battery back-up.
A.I.M (Automatic Incident Monitor). (Not all Models) (see page 300.3 for details)
Low battery indicator (Not All Models)
Touchpad alarm power failure or temperature deviation outside alarm set limits triggers audible and
visual warning. (Selected Models)
Independent high and low alarm setpoints adjustable
o
in 1
C increments (Not all Models)
Low voltage indicator light (Selected Models)
Exterior alarm contacts for remote alarm
CABINET CONSTRUCTION
Recessed, heavy-duty casters
Noise abatement insulation package.
Minimum 5” foamed in placed urethane insulation,
CFC free.
Technical Information 300.1
All-steel cabinet with high-impact epoxy finish for
easy cleaning.
Built-in access port, 1” diameter
Four (4) stainless steel interior shelves, (3) adjustable.
Anti-roll brakes
Five inner doors with positive latches
ADDITIONAL ULTIMA II FEATURES.
EXTREME AMBIENT ALERT
This alarm monitors the ambient temperature in the
area of the freezer. If the temperature reaches 99f (+/3f), it could possibly effect the performance or reliability of your freezer, and the Extreme Ambient
Alert will activate. This alarm is also under the umbrella of AIM, so that you can be sure that safe
temperatures exist even when no one is present.
Comfortable ambient conditions lead to long life of
your freezer and safety of your samples.
LIFE GUARD
Life Guard actively monitors the condition of the
compressors in the freezer. If the compressors should
enter a harmful stress condition that could cause them
harm, the Life Guard automatically turns the unit off
and allows the compressors to cool down.
The compressors will be automatically started when
the conditions are improved. During a Life Guard
alert, the temperature inside your chamber may warm
Slightly
compared to having a compressor failure and a complete warm up of your samples. If Life Guard is ever
activated, please call a service provider immediately
to investigate. Factors that may cause Life Guard to
activate include extreme ambient conditions, extreme
. However, this is a far superior option when
voltage conditions, excessive loading with warm
product, extremely dirty condenser filters, doors left
open, and other unusual circumstances.
SET POINT SECURITY
Not available on all models
Set Point Security allows you to lock in the control
set point and alarm set points of your freezer to ensure that they may not be changed, accidentally or
intentionally. When the key is in the third key position (alarm on), Set Point Security deactivates the up
and down buttons on the control panel. This makes it
impossible for the control set point, warm alarm, and
cold alarm to be changed. Of course, pressing the
appropriate buttons can still see these temperatures.
AIM (AUTOMATIC INCIDENT MONITOR)
Not available on all models
Although you cannot see this feature, it is extremely
important for the ongoing safety of your stored samples. AIM monitors the temperature of the freezer
and compares it to the alarm limits you have set. If
the unit temperature ever exceeds an alarm limit, the
appropriate alarm will flash rapidly, about one flash
per second. If this condition ever occurs while you
are not present and then self-corrects, AIM is activated. AIM lets you know that a temperature
deviation occurred while you were gone but has selfcorrected. Instead of flashing rapidly, the alarm will
flash slowly, about one flash every 3 seconds. The
most extreme chamber temperature registered during
this deviation can be seen by simultaneously pressing
the appropriate alarm set point button and the cabinet
temperature button. This feature guarantees that you
always know the temperatures of your stored samples. The slow flash of the AIM alarm can be reset by
pressing the alarm reset button. The AIM monitor
works for warm alarm, cold alarm, Life Guard, power
failure, and extreme ambient alert.
Technical Information 300.2
RECOMMENDED TOOL LIST
One of the keys to doing a job correctly is using
proper tools. The following list is NOT all-inclusive
of the tools you might need to perform the procedures
listed in this manual. However, these tools will be
needed to perform many of the steps in these procedures.
* Vacuum Pump (Capability of 50 microns)
* Electronic Digital Thermometer (Reads below
200C) Compatable to Type “T”
* Compound Gauge Set (4 way) with Hoses
* AC Volt-Watt Meter
* Hermetic Unit Analyzer
* Manometer
* Tachometer
* Portable Oxy-Acetylene Torch Set
* Regulator and Lines for Nitrogen
* Flaring Set and Swaging Tool Set
* Standard Hand Tools (Screw Drivers, Wrenches,
Pliers, etc.)
* Refrigerants; R404, R134a, R508B, and R290
(Instrument Grade Propane)
* Grit Cloth for Cleaning Lines
* Cordless Driver-Drill (Reversible)
* Vacuum Gauge (Electronic) Televac
* Electronic Leak Detector (CFC and Non-CFC)
* Electronic Refrigerant Charging Scales
* Multimeter Volt-Ohm, Amp Meter (Analog and
Digital)
* On-Off Cycle Chart Recorder
* Sling Psychrometer
* Presto Light Torch
* Dry Nitrogen (Portable “R” Type Cylinder
* Set of Flare Hand Valves or Process Tube Adapters
* Tubing Cutter(s) Large and Small
* Pinch Off Tool
* Recovery System (with tanks)
* Good Set of Tubing Bender
* Tube Reamer
Technical Information 300.3
PREVENTIVE MAINTENANCE
Preventive maintenance is the best way to ensure that
the unit you own or service continues to operate at its
optimum level. The following instructions will help
you in your preventive maintenance program.
CONDENSER CLEANING
Clean the condenser at least semi-annually; or more
often if the equipment is located in a dust prone area.
CONDENSER FILTER CLEANING
Clean the condenser filter every two or three months.
Shake or vacuum the filter first, then rinse the filter in
clean water. Let the filter dry, then replace the filter
on the unit.
GASKET MAINTENANCE
Periodically check the gaskets around the door or lid
for punctures or tears. Gasket leaks are indicated by a
streak of frost build up in the interior of the cabinet.
Keep the lid and door gaskets clean and frost free by
wiping gently with a soft cloth or brush.
DEFROST PROCEDURE
Defrost the cabinet every six to twelve months, depending on the amount of ice or frost on the cabinet
interior. To reduce ice build up, daily brushing (with
a soft brush) of the cabinet interior keeps the normal
frost from turning into ice.
To defrost the cabinet, remove your product, turn the
unit off by the key switch, and unplug the power
cord. Let the cabinet warm to room ambient temperature, then wipe down the cabinet interior using dry
towels. Wash and rinse the interior of the cabinet
with a solution of baking soda and warm water. Turn
the unit on and allow it to pull down to set-point temperature, then reload your product back into the
freezer.
ALARM BATTERY MAINTENANCE
Check the condition of the alarm battery at least annually. Check the input charging voltage and the
battery output voltage. The charging voltage input is
14 to 35 VDC, depending upon the model. The battery voltage at full charge is 12 VDC.
FAN MOTORS
Most fan motors used today are a maintenance free
(sealed type) and do not require oil maintenance, but
some previous motors may come with an oil port.
Inspection of the motor will determine which type is
being used. If an oil port is present, then a couple of
drops of oil once annually is sufficient.
CABINET LEVELING
Check the cabinet to ensure that it is level. Check
from the front to the back and then side to side, check
the level on a (6) month schedule.
CABINET CLEARANCE
Ensure that the cabinet has proper clearance, a minimum of six inches of space from the sides, back and
top of the cabinet is required.
VOLTAGE REQUIREMENTS
Check the voltage requirements every three to six
months. Verify that the source voltage is within
+10% and –5% of the rated data plate voltage.
CENTER AIR TEMPERATURE VALIDATION
Check the center air temperature using a thermocouple located physically in the geometric center of the
cabinet versus the control panel electronic display.
The temperature should match the display within +/1C at the coldest setting for most models.
ELECTRICAL WIRES
Check the electrical control box for any burnt or discolored wires due to lose connections or low voltage
conditions.
a. Maintenance should only be performed by trained
personnel.
b. For additional information or assistance you may
contact TECHNICAL SERVICES at (800) 438 4851 or (828) 658 - 2818
Technical Information 300.4
SECTION 400 - MAINTENANCE AND REPAIR PROCEDURES
CABINET
LEVELING OF A CHEST OR UPRIGHT FREEZER
A unit that is not level will not operate properly. It
can cause imbalances in products and can cause problems in the refrigeration system. An unleveled unit
can also cause misalignments of other components
such as the door, lid, and/or the gasket.
The following steps will aid you in aligning a freezer
unit.
Step 1: Locate the freezer in a level area free from
vibration, with a minimum of six (6) inches
(15.24 cm) of space on the sides, rear, and
top. Also, allow enough clearance so that the
door or lid can swing open at least 90 degrees.
Step 2: Place a carpenters level along the rear edge
of the unit, and then along the right hand
edge of the unit, to determine the offset from
level.
Step 3: To level chest models, leave the casters in
place and shim the low wheel/caster until
the carpenter level indicates the unit is level
from front to back and from side to side. Use
strips of sheet metal at least 0.5 inches (1.25
cm) wider than the caster, placed underneath
the caster to level the unit.
Step 4: To level upright models, use a 3/4” (19mm)
open-end wrench to turn the leveling leg until the carpenter level indicates the unit is
level from front to back, and from side to
side.
Figure 401-1
Typical Chest and Upright Caster
Maintenance and Repair Procedures 400.1
DEFROSTING A CHEST OR UPRIGHT FREEZER
Every time a freezer is opened, a certain amount of
water, depending on the relative humidity, enters the
freezer compartment. This water obviously turns to
frost, collecting on the sides and surfaces of the
freezer. This frost accumulation can lead to decreased
efficiency and temperature control.
It is recommended that the unit be defrosted when the
ice accumulation reaches a thickness of 0.25”
(6.4mm) or more.
Step 1: Transfer product to another freezer of equal
temperature.
Step 2: Leave the unit set for the desired operating
temperature, turn the power/key switch to
the Power Off position, and unplug the
unit’s power cord.
Step 3: Open the door or lid and leave the unit undis-
turbed for a minimum of twenty-four (24)
hours; failure to do so could cause oil logging problems when the unit is restarted,
thus preventing the unit from getting fully
cold.
Step 4: Use towels or a sponge and bucket to collect
the water on the cabinet floor and dry the
walls.
NOTE On upright models, towels should
Step 5: Start the unit by closing the door or lid, plug
Step 6: Leave the temperature control set for the
Step 7: If the unit has a selectable Alarm On posi-
Step 8: Monitor for proper operation.
be placed in the cabinet floor and
on the laboratory floor immediately
in front of the cabinet to prevent the
water from presenting a slip hazard.
the power cord into the wall receptacle, and
turn the power switch to the Power On position.
desired operating temperature and allow 1012 hours of operation in order for the unit to
return to operating temperature.
tion, select the Alarm On position after the
temperature display is colder than the Warm
Alarm setpoint.
Maintenance and Repair Procedures 400.2
DOOR ADJUSTMENT OF AN UPRIGHT FREEZER
The following steps will aid you in adjusting the
hinges of an upright Ultra Low Temperature freezer.
Step 1. Ensure the freezer cabinet is level from front
to back, and left to right.
Step 2. Install a bar clamp with 2” x 4” wooden
blocks, as shown in Figure 403-1.
Step 3. Loosen the mounting screws that hold the
hinge to the door.
Step 4. Align the door so that the top and latch edges
are flush with the cabinet.
Step 5. Tighten the bar clamp to produce secure gas-
ket seal.
Step 6. Tighten all mounting screws.
Add picture for new hinge
Figure 403-1
Hinge Adjustment Configuration
Figure 403-2
Upright Freezer Hinge
Maintenance and Repair Procedures 400.3
LID ADJUSTMENT OF A CHEST FREEZER
The following steps will aid you in adjusting the lid
of a chest type Ultra Low Temperature freezer.
Step 1. Ensure the freezer cabinet is level from front
to back, and left to right.
NOTE The hinge mounting screws are
elongated for up and down positioning to obtain proper gasket seal
on hinge side of lid.
Add warning symbol
CAUTION The hinge is under considerable
spring tension. Removal or excessive loosening of screws could
cause hinge to fly up and cause
injury.
Step 2. Loosen the hinge screws that attach the hinge
to the cabinet.
Step 3. Align the cabinet for proper gasket seal.
Step 4. Tighten the hinge mounting screws.
Step 3. Fully open the lid
Step 4. With a 3/4” wrench, turn the hinge tension
nut to compress the spring until the lid remains open.
Step 5. Close the lid and monitor unit for proper op-
eration
Figure 404-1
Chest Freezer Hinge
Maintenance and Repair Procedures 400.4
UPRIGHT FREEZER GASKET REPLACEMENT
The following steps will aid you in replacing the inner or outer gasket of an upright Ultra Low
Temperature freezer.
NOTE The new gasket will be wrinkled
and folded when it is unpacked.
Immerse the gasket in warm water
until it becomes pliable. Lay the
gasket flat and allow to dry. Care
should be taken not to stretch or
tear the gasket during handling.
Step 1. Transfer product to another freezer of equal
temperature.
Step 2. Leave the unit set for the desired operating
temperature, turn the power/key switch to
the Power Off position, and unplug the
unit’s power cord.
Step 3. Remove the desired (inner or outer) gasket
by pulling it straight away from the door.
Step 4. Align the corners
Step 5. Press the retaining rib (corners first) on the
new gasket into the groove in the door using
a rubber hammer if necessary.
NOTE You may find it easier to remove
the door and lay it on a flat surface
with the gasket side up.
Add picture of new gasket
Figure 405-1
Typical Gasket
(inner or outer)
Figure 405-2
Gasket Insertion
Maintenance and Repair Procedures 400.5
CHEST FREEZER GASKET REPLACEMENT
The following steps will aid you in replacing the gasket on a chest type Ultra Low Temperature freezer.
NOTE The new gasket will be wrinkled
and folded when it is unpacked.
Immerse the gasket in warm water
until it becomes pliable. Lay the
gasket flat and allow to dry. Care
should be taken not to stretch or
tear the gasket during handling.
Add warning symbol
CAUTION The hinges on a chest freezer are
under tension when the lid is
closed. Care should be taken to
avoid injury.
Step 1. Transfer product to another freezer of equal
temperature.
Step 2. Leave the unit set for the desired operating
temperature, turn the power/key switch to
the Power Off position, and unplug the
unit’s power cord.
Step 3. Remove the 5/16” screws that attach the lid
hinges to the cabinet
Step 4. Remove the lid from the cabinet.
Step 5. Lay the lid, gasket side up, on a flat surface
and remove the desired (inner or outer) gasket by pulling it straight away from the lid.
Figure 406-1
Chest Freezer Hinge
Figure 406-2
Chest Gasket
Maintenance and Repair Procedures 400.6
Step 6. Lay the new gasket in place and align the
corners.
Step 7. Press the retaining rib (corners first) on the
new gasket into the groove in the lid using a
rubber hammer if necessary.
Step 8. Install the lid
Step9. Adj. Per Adjustment Procedure
Step 10
. Reattach power supply.
Step 11
: Turn power key on.
Step 12
: Check unit for proper operation.
Figure 406-3
Gasket Insertion
Maintenance and Repair Procedures 400.7
HANDLE REPLACEMENT FOR CHEST FREEZER
The most used manual component of a chest freezer
is the lid handle. The following steps are provided to
give instructions on how to replace the handle of a
-85C freezer.
Step 1: Locate and remove the screws securing the
handle. Be sure to retain the screws and any
washers used.
Step 2: Remove the handle from the lid.
Step 3: Set the new handle in its proper place and
secure it to the lid using the screws and
washers used in Step 1.
Figure 407-1
Lid Handle
Maintenance and Repair Procedures 400.8
UPRIGHT FREEZER CAM LATCH DOOR LOCK REPLACEMENT
The following steps are provided to give instructions
on how to replace the latch of an upright freezer.
Before repairing, identify any circumstances contributing to latch problem such as shipping damage,
excessive ice build-up, maneuvering overload, improper alignment of the latch of lid/door hinges,
cabinet breaker geometry, or other. Review with
owner and factory service department at 800-438-
4851.
REMOVE UNWANTED LATCH.
Step 1 If necessary, secure door temporarily with
strapping tape.
Step 2. Remove rear strike cover and rear strike.
Step 3. Remove front cover by removing fasteners
then sliding vertically upward. Note con-
cealed fasteners behind door handle.
Step 4. Remove latch assembly. Note, access holes
allow removal of latch mounting fasteners
without disassembly
Step 5. Inspect door and cabinet for damage. Pay
careful attention to mounting points.
Step 6. Repair threads as necessary with ¼-20 tap or
drill 25/64 (PN 38126H03) then replace with
nutsert (PN305465H01).
NSTALL NEW LATCH
Step 1. Inspect new latch for workmanship flaws
and/or handling damage. Mechanism should
have a tight feel, lock should engage
smoothly and fully.
Step 2. Attach new strike to cabinet with (4) ¼-20
fasteners and hardened washers. Align hori-
zontally flush with cabinet edge or with a
slight overhang. Torque 60 in-lb. (6.75 N-
m).
NOTE
Inability to achieve torque
may indicate damaged
threads
Strike (2b) and Latch (2c) Cover
Strike and Latch Mounting Screws
Figure 408-1
Mounting Screws
Figure 408-2
and / or Access Holes
Maintenance and Repair Procedures 400.9
Step 3. Attach latch assembly to door with (4) ¼-20
fasteners and hardened washers. Align verti-
cally so top surface is flush with rear strike.
Torque 60 in-lb. (6.75 N-m).
NOTE Disassembling latch is not required
nor recommended.
Step 4. Put a small amount of white lithium grease
at strike point.
CAUTION Excessive door compression may
damage latch and/or cabinet
.
Step 5. Adjust rear strike horizontally to achieve
exterior gasket compression thickness of ap-
proximately 11/16 inch (18mm).
Step 6. Fine tune gasket compression with miro-
adjustment screw located in catch. Install
front and rear covers. Top surfaces should
align.
CAUTION Only the micro-adjustment screw’s
chamfered portion should extend
beyond the catch surface to prevent snagging on the strike during
close. If necessary, loosen and
reposition strike rearward to assure
smooth operation.
Step 7. Verify operation. Neither latch nor cabinet
panels should deflect noticeably during op-
eration. No interference should exist
between latch components and freezer. Fas-
teners remain secure. Padlock and built in
lock engage smoothly.
NOTE 2 –4 drops ICI46H POE lubricant
may be squirted into main or interlink bearings to eliminate squeaks.
Maintenance and Repair Procedures 400.10
CHEST FREEZER LID LOCK REPLACEMENT
The following steps will aid you in replacing the lock
on the lid of a chest type Ultra Low Temperature
freezer.
CAUTION Disconnect all power to unit.
Step 1. Remove the screws at the rear of the control
housing cover.
Step 2. Slide the cover towards the rear of the unit
approximately two inches.
Step 3. Turn the control housing cover over. Remove
the screw securing the pivoting tab to the
locking mechanism.
Step 4. Remove the pivoting tab.
Step 5. Remove the nut securing the locking mecha-
nism to the cover.
Step 6. Remove the locking mechanism from the
cover.
Step 7. On the new locking mechanism, remove the
screw securing the pivoting tab to the lock-
ing mechanism.
Step 8. Install the locking mechanism into the cover.
Step 9. Install the pivoting tab.
Step 10: Verify the direction of rotation of the lock-
ing mechanism when the key is turned is
correct.
Step 11: Install the screw to secure the pivoting tab.
Step 12: Install the cover. A rubber hammer may be
needed to install the control housing cover.
Step 13: Install the screws at the rear of the control
housing cover.
Figure 409-1
Chest Freezer Lid Lock
(installed on the unit)
Figure 409-2
Chest Freezer Lid Lock Component Parts
Maintenance and Repair Procedures 400.11
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