VWR VWH07CESA User manual

VWR Explosion-Proof and Flammable
Materials Storage Laboratory
Refrigerators and Freezers
Installation and Operation
331732H04 • Revision A • 10/06/2020

IMPORTANT Read this instruction manual. Failure to follow the instructions in this manual can result in
damage to the unit, injury to operating personnel, and poor equipment performance.
CAUTION All internal adjustments and maintenance must be performed by qualified service personnel.
Material in this manual is for informational purposes only. The contents and the product it describes are sub-
ject to change without notice. VWR International, LLC. and VWR International, bvba make no representations
or warranties with respect to this manual. In no event shall VWR International, LLC. or VWR International, bvba
be held liable for any damages, direct or incidental, arising from or related to the use of this manual.
Legal addresses of VWR:
© 2020 VWR Inc. All rights reserved.
United States
VWR International, LLC
100 Matsonford Rd
Radnor, PA 19087
800-932-5000
http://www.vwr.com
Europe
VWR International, bvba
Researchpark Hassrode 2020
Geldenaaksebaan 464
B-3001 Leuven
[phone]
http://be.vwr.com

Contents
Models......................................................................... 1
Safety Information........................................................ 2
Explanation of Safety Symbols ................................. 2
Intended Use ............................................................... 3
Flammable Materials Storage
Refrigerators and Freezers ........................................... 4
Overview .................................................................. 4
Product Specification ............................................... 5
Explosion-Proof Refrigerators and Freezers ................. 6
Overview .................................................................. 6
Product Specification ............................................... 7
Unpacking and Inspection............................................ 8
Unpacking................................................................ 8
Visible Loss or Damage............................................ 8
Concealed Loss or Damage..................................... 8
Operating Conditions ................................................... 9
Installation.................................................................... 10
Selecting a Location................................................. 10
Leveling the Unit....................................................... 10
Electrical Connection................................................ 10
Be Advised............................................................... 10
How to Seal Killark® Box Conduit............................. 11
Electric Connection Check Points............................. 12

Start-Up Procedure...................................................... 13
Restart Procedure.................................................... 13
How to Save Energy................................................. 13
Safety Tips ............................................................... 13
Maintenance ................................................................ 14
Cleaning the Unit...................................................... 14
Cleaning Interior/Exterior/Door Gaskets.................... 14
Cleaning the Condenser........................................... 14
Manual Defrost Procedure........................................ 14
Transportation and Storage...................................... 15
Troubleshooting........................................................... 16
Wiring Diagram ............................................................ 17
Flammable Materials Storage
Refrigerators and Freezers ....................................... 17
Explosion-Proof Refrigerators and Freezers.............. 18
End of Life Care ........................................................... 19
Warranty ...................................................................... 20
Regulatory Compliance................................................ 21
Product Safety ......................................................... 21
Additional Regulations and Markings........................ 21
Contact Information .................................................... 22

Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers Models | 1
Models
This manual covers the installation and operation instructions for following models:
Refrigerators and Freezers
Explosion Proof VWH07CESA
Flammable Material Storage VWH07CFSA

2 | Safety Information Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers
Safety Information
It is your responsibility to understand the product's proper
function and operational characteristics. This instruction
manual should be thoroughly read and all operators given
adequate training before installing and operating the unit.
Awareness of the stated cautions and warnings, and
compliance with recommended operating parameters
together with maintenance requirements are important for
safe and satisfactory operation. The unit should be used for
its intended application; alterations or modifications will void
the warranty.
This product is not intended, nor can it be used, as a sterile or
patient connected device.
Explanation of Safety
Symbols
Safety Alert: Important operating instructions.
To reduce the risk of injury or poor performance
of the unit. Read the user manual before putting
the equipment into operation.
WARNING: Indicates an immediately hazardous
situation, which if not avoided, will result in death
or serious injury.
CAUTION: Indicates an immediately hazardous
situation, which if not avoided, may result in
minor to moderate injury.
WARNING: Avoid contact with cold freezer
surfaces potential for cold burns or skin sticking
to cold surfaces.
WARNING: Units are charged with hydrocarbon
refrigerant (R600a). Only qualified service
personnel should service this unit.
WARNING: Risk of fire or explosion. Flammable
refrigerant used. To be repaired only by trained
service personnel. Do not puncture refrigerant
tubing.
WARNING: Use of this symbol involves risk of
electric shock.
Do not modify or use power supplies other than
OEM equipment. Connection of the power supply
may require a properly grounded receptacle.
Potential for electrical shock or equipment
damage exists if precautions are not followed.
Note: Notes alert you to pertinent facts and conditions.
DANGER RISK OF CHILD ENTRAPMENT Before
you throw away your freezer:
• Take off doors.
• Leave the shelves in the place so that
children may not easily climb inside.
WARNING: If the equipment is used in a manner
not specified by the manufacturer, the protection
provided by the equipment may be impaired.
WARNING: Risk of fire or explosion. Flammable
refrigerant used. Do not use mechanical devices
to defrost the unit.
WARNING: No equipment that uses an open
flame should be placed inside the refrigerator.
This will harm the unit, hamper functionality and
compromise your safety.
WARNING: This product can expose you to
chemicals including Nickel (Metallic) which is
known to the State of California to cause
cancer.For more information go to
www.P65Warnings.ca.gov
Note: Nickel is a component in all stainless steel
and some other metal components.

Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers Intended Use | 3
Intended Use
The Flammable Material Storage and Explosion Proof
Refrigerators and Freezers described in this manual are
intended for storage of flammable inventory/samples. These
products conform to the appropriate standards by passing all
requisite testing.
Explosion Proof Refrigerators and Freezers are intended to
use in classified areas requiring Class I, Groups C and D as
defined in NFPA 70 Articles 500-501 and NFPA 45 and OSHA
29 CFR1910.307.
The Refrigerators and Freezers described in this manual are
for professional use only. These products are intended for use
in research for the storage of samples or inventory in the
following temperature ranges:
Refrigerators 33.8°F to 53.6°F (+1°C to +12°C)
Freezers -4°F to 10.4°F (-20°C to -12°C)
These are not considered as medical devices and have
therefore not been registered with a medical device regulatory
body (e.g. FDA): that is, it has not been evaluated for the
storage of samples for diagnostic use or for samples to be re-
introduced to the body.
Note: Do not store corrosive materials in these units. Any
damage which occurs due to storage of corrosives will not be
covered under warranty claims.
Follow site protocols to identify materials of corrosive nature.
WARNING: Only Explosion Proof or Flammable
Material Storage Refrigerator and Freezer are to
be used for the storage of flammable inventory/
samples.
WARNING: Flammable Material Storage
Refrigerator and Freezer are NOT designed for
use in Class I, Groups C and D environments,
which require an Explosion-Proof Refrigerators
and Freezers.

4 | Flammable Material Storage and Explosion Proof Laboratory Refrigerators and Freezers
Flammable Materials Storage
Refrigerators and Freezers
Overview
Conventional refrigerators and freezers are not suitable for
storing flammable materials. Such units have components in
their electrical and refrigeration systems that can trigger
explosions of flammable air-vapor mixtures inside the unit.
Flammable Materials Storage (FMS) Refrigerators and
Freezers are designed for use in locations, which are
classified by the Authority Having Jurisdiction (AHJ) as not
hazardous. Under normal operating conditions the build up or
presence of flammable vapors will not occur in the
environment external to the unit. (Commonly known as
“Ordinary Locations”)
FMS Refrigerators and Freezers are NOT designed for
use in Class I, Groups C and D environments, which
require an Explosion-Proof Refrigerators and Freezers.
This is not an Explosion Proof Refrigerator and Freezer but it
has been designed to permit safe storage of materials
producing flammable vapors. Containers should be well-
stoppered or tightly closed.
FMS Refrigerators and Freezers are designed and evaluated
by Underwriters Laboratories (UL) to meet the requirements of
the National Fire Protection Association Standards Nos. 45
and 70. These units have no internal electrical components
that could trigger an explosion or fire of hazardous materials
inside the unit.
As this unit uses R600a refrigerant. This unit is intended for
use in laboratories in commercial, industrial or institutional
occupancies defined in the safety standard for Refrigeration
Systems ASHRAE 15.
These units are ideal for storing cyclopropane, ethyl ether,
ethylene, acetone, alcohol, benzene, butane, gasoline,
hexane, lacquer solvent vapors, naphtha, natural gas or
propane along with many other potentially hazardous
materials.
Thermocouples for building monitoring systems must be
wired through an electrical barrier designed to provide
isolation against voltage and current spikes.
These could cause a spark resulting in fire or explosion. It is
your responsibility to meet these requirements. Thermo
Scientific cannot assist with the selection of devices,
recommend, approve or design any device or monitoring
circuit.
WARNING: For Flammable Materials Storage
Refrigerators and Freezers where flammable
materials are stored in the cooling chamber, the
cooling chamber is considered a Class I Div 1 or
Class I Zone 1 hazardous location. Any
monitoring devices placed in the cooling
chamber must have an intrinsically safe rating
from an appropriate certification body, such as
UL, CSA, FM etc. (this includes battery or solar
powered devices).

Flammable Material Storage and Explosion Proof Laboratory Refrigerators and Freezers| 5
Product Specification
Note: Amps listed are at normal run mode, starting amps may be higher.
MODEL VWH07CFSA - 7.1 Cu. ft.
22" Wide, Refrigerator and Freezer
Features:
• Refrigerator: 3 Adjustable Shelves
• Freezer: 1 Adjustable Shelf
• Manual defrost
• White color
VWH07CFSA
Refrigerator Chamber Dimensions
H x W x D inches (cm)
36.5" x 17.5" x 17"
(92.7 x 44.5 x 43.2 cm)
Freezer Chamber Dimensions
H x W x D inches (cm)
10.38" x 15.5" x 16"
(26.4 x 39.4 x 40.6 cm)
Exterior Dimensions
H x W x D inches (cm)
56.63" x 21.5" x 25.75"
(143.8 x 54.6 x 65.4 cm)
Electrical Characteristics
Volts/Hz, Amps 115/60, 1
Refrigerator Temperature Range
°F (°C)
33.8° to 53.6°
(1° to 12°)
Freezer Temperature Range
°F (°C)
-4° to 10.4°
(-20° to -12°)
Net Weight lbs. (kg) 89 (40.5)

6 | Flammable Material Storage and Explosion Proof Laboratory Refrigerators and Freezers
Explosion-Proof Refrigerators and
Freezers
Overview
The Authority Having Jurisdiction (AHJ) determines if work
areas are designated as a hazardous location with respect to
the presence of flammable gases or vapors. Such locations
are defined in (National Fire Protection Agency) NFPA 70
Articles 500- 501, OSHA 29 CFR1910.307 and NFPA 45.
Some of these classified areas are expected to experience
concentrations of flammable gases and/or vapors at or above
their lower flammability limits for extended periods of time.
The construction of our Explosion-Proof Refrigerators and
Freezers has been evaluated by Underwriters Laboratories
(UL) and are suitable for use in classified areas requiring Class
I, Groups C and D* protected equipment. The electrical
components such as thermostats, wiring, splices, relays and
compressor motors on Explosion-Proof Refrigerators and
Freezers are safely housed within Explosion-Proof enclosures
and conduit. Compressor surface temperatures have been
evaluated and determined to remain below the flash point of
materials found in Class I, Groups C and D. All models have
heavy-gauge, rigid, steel construction with a durable enamel
finish. Interiors have epoxy enamel or ABS plastic
construction. Each unit is insulated throughout for energy-
efficient operation.
These units are designed to meet the standards established
by Underwriters’ Laboratory, Inc., OSHA and National Fire
Protection Association for storage of hazardous materials.
On Explosion Proof Refrigerators and Freezers all ferrous
flame paths are protected from corrosion by the use of
petroleum jelly (or petrolatum or soap-thickened mineral oils).
It is important to note that Explosion-Proof Refrigerators and
Freezers must be connected to the power supply source by
rigid metal conduit with proper fittings suitable for Class I,
Groups C and D* hazardous locations.In addition, the wires
inside the conduit must be sealed. Explosion-Proof
Refrigerators and Freezers require being hard wired into the
building electrical system and therefore require a qualified
electrician to install as per the “local electrical requirements
and NEC Standard” or “Canadian Electrical Standard”.
*The notation Class 1, Groups C and D is an accepted
abbreviation for Class I, Div 1, Groups C and D; Class I Zone
1 Group IIB.
Thermocouples for building monitoring systems must be
wired through an electrical barrier designed to provide
isolation against voltage and current spikes, which could
cause a spark resulting in fire or explosion. It is the your
responsibility to meet these requirements. Thermo Scientific
cannot assist with the selection of devices, recommend,
approve or design any device or monitoring circuit.
Thermo Scientific reserves the right to change specifications
without prior notice.
Note: If any questions pertaining to electrical safety arise,
please refer to article 501 of the US National Electrical Code.
WARNING: For Explosion-Proof Refrigerators
and Freezers where flammable materials are
stored in the cooling chamber, the cooling
chamber is considered a Class I Div1 or Class I
Zone 1 hazardous location. Any monitoring
devices placed in the cooling chamber must have
an intrinsically safe rating from an appropriate
certification body, such as UL, CSA, FM etc. (this
includes battery or solar powered devices).

Flammable Material Storage and Explosion Proof Laboratory Refrigerators and Freezers| 7
Product Specification
Note: Amps listed are at normal run mode, starting amps may be higher.
MODEL VWH07CESA - 7.1 Cu. ft.
22" Wide, Two-door Refrigerator and Freezer
Features:
• Refrigerator: 3 Adjustable Shelves
• Freezer: 1 Adjustable Shelf
• Manual defrost
• White color
VWH07CESA
Refrigerator Chamber Dimensions
H x W x D inches (cm)
36.5" x 17.5" x 17"
(92.7 x 44.5 x 43.2 cm)
Freezer Chamber Dimensions
H x W x D inches (cm)
10.38" x 15.5" x 16"
(26.4 x 39.4 x 40.6 cm)
Exterior Dimensions
H x W x D inches (cm)
56.63" x 21.5" x 27.5"
(143.8 x 54.6 x 69.8 cm)
Electrical Characteristics
Volts/Hz, Amps 115/60, 1
Refrigerator Temperature Range
°F (°C)
33.8° to 53.6°
(1° to 12°)
Freezer Temperature Range
°F (°C)
-4° to 10.4°
(-20° to -12°)
Net Weight lbs. (kg) 101 (45.8)

8 | Unpacking and Inspection Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers
Unpacking and Inspection
Unpacking
This should be inspected upon delivery. When received,
carefully examine for any shipping damage before unpacking.
If damage is discovered, the delivering carrier should both
specify and sign for the damage on your copy of the delivery
receipt.
Visible Loss or Damage
Note any external evidence of loss or damage on the freight
bill, or express receipt, and have it signed by the carrier’s
agent. Failure to adequately describe such external evidence
of loss or damage may result in the carrier’s refusing to honor
your damage claim. The form required to file such a claim will
be supplied by the carrier.
IMPORTANT: Failure to request an inspection of damage
within a few days after receipt of shipment absolves the
carrier from any liability for damage.You must call for a
damage inspection promptly.
Concealed Loss or
Damage
Concealed loss or damage refers to loss or damage, which
does not become apparent until the merchandise has been
unpacked and inspected. If either occur, make a written
request for the carrier’s agent within 15 days of the delivery
date; then file a claim with the carrier since the damage is the
carrier’s responsibility.
If you follow the above instructions carefully, we will guarantee
our support of your claim to be compensated for loss from
concealed damage.
DO NOT, FOR ANY REASON RETURN THIS UNIT WITHOUT
FIRST OBTAINING AUTHORIZATION.
CAUTION: DO NOT REMOVE, under any
circumstance, the grounding prongs from the
3-prong power cord supplied with all FMS
refrigerators and freezers.
CAUTION: DO NOT USE electrical extension
cords that may result in voltage loss and possible
hazardous operation.

Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers Operating Conditions | 9
Operating Conditions
The units described in this manual are classified for use as
stationary equipment in a Pollution Degree 2 and Over voltage
Category II environment.
These units are designed to operate under the following
environmental conditions:
• Indoor use
• Altitude up to 2,000 m (6512 feet)
• Maximum relative humidity 65%, non-condensing
• Temperatures: 59°F to 90°F (15°C to 32°C)
• Main supply voltage fluctuations should not exceed by
±10% of the nominal voltage.

10 | Installation Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers
Installation
Selecting a Location
Choose a location for theVWH07CFSA/VWH07CESA
(Refrigerator and Freezer) that provides a clearance of 12 in.
at the top, 4 in. at the rear and 4 in. on each side.
Appropriate electrical power must be available. Locate the
refrigerator/freezer within eight feet of the power outlet so that
no extension cord is required. Attach the refrigerator/freezer
to the facility’s electrical supply as directed by the National
Electrical Code.
Leveling the Unit
This refrigerator/freezer must be level in order to provide
adequate condensate drainage as well as proper door
alignment and operation. The refrigerator/freezer should be in
its final operating location and set so that it is firmly positioned
on the floor.
Electrical Connection
Determine the total amount of current presently being used by
other apparatus connected to the circuit that will be used by
this refrigerator. It is critical that this added current demand
and other equipment on this circuit not exceed the rating of
the fuse or circuit breaker in use.
The frequency and nominal voltage requirements for the unit
are specified on the data plate. Supply this unit with an
electrical source that meets these requirements only. Low line
voltage is often the cause of service complaints. With the unit
running, check that the line voltage is within ±10% of that
specified on the data plate.
Units must be connected to a grounded outlet matching the
nameplate and/or the information furnished in this manual. If
you are not sure about the outlet, you should contact a
qualified electrician for assistance.
The Unit should always be connected to a dedicated power
source. 1
Be Advised
CAUTION: Be sure the voltage supplied to the
refrigerator/freezer is equal to that specified on
the data plate.
WARNING: For personal safety, this unit must
be properly grounded before use.
WARNING: DO NOT REMOVE, under any
circumstance, the grounding prongs from the
3-prong power cord supplied with all FMS
refrigerators and freezers.
WARNING: DO NOT USE electrical extension
cords, it may result in voltage loss and possible
hazardous operation.
WARNING: Explosion-Proof Refrigerators and
Freezers do not come with line cords. They
require rigid conduit to be run directly in order to
seal off the fitting on thermostat housing. This
should be done by a licensed electrician and
follow all local and electrician and follow all local
electrical codes. If any questions pertaining to
electrical safety arises, please refer to article 501
of the National Electrical Code (NFPA70).
WARNING: UNLESS UNIT IS SPECIFICALLY
DESIGNED FOR COMBUSTIBLE OR
FLAMMABLE ATMOSPHERES DO NOT USE IN
THE PRESENCE OF FLAMMABLE OR
COMBUSTIBLE MATERIALS OR EXPLOSIVE
GASES. DO NOT USE IN THE PRESENCE OF
PRESSURIZED OR SEALED CONTAINERS—
FIRE OR EXPLOSION MAY RESULT CAUSING
DEATH.
CAUTION: Before connecting the final power
supply, check the electrical characteristics of the
unit nameplate to see that it is in agreement with
the power supplied. In addition, power should be
wired to the unit according to the electrical
schematic and all applicable codes. Only
qualified electricians should work on the electrical
portion of any unit Installation and service.
CAUTION: Storage by user of any materials in
the product that may cause a deterioration of the
product shall be deemed to constitute abnormal
and improper usage of the product for purposes
of this warranty.

Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers Installation | 11
How to Seal Killark® Box
Conduit
To Seal Killark® Box Conduit with Fiber and Sealing
Compound to Help Protect Against Explosions (Explosion-
Proof Refrigerators and Freezers only):
The purpose of the procedure that follows is to build fiber
rope dams on the left and right hubs of the horizontal conduit.
The fiber rope damns will surround conduit wiring that is
housed inside the horizontal conduit. When both the left and
right fiber rope dams have been pressed into place, sealing
compound is poured between the two and forms into an
airtight plug.
All of this is done in order to prevent the very real threat of gas
entering the Killark box and a resulting serious explosion. After
the unit wires have been pulled through the horizontal conduit
the following procedure is required:
• Turn power off at the circuit breaker before proceeding.
• Place a small amount of sealing compound granules,
enclosed, into a clean mixing vessel. Add small amounts
of water while stirring until a thick paste is formed, then
carefully continue adding smaller amounts of water until a
thick gravy consistency is achieved—NOT WATERY.
Discard any material that becomes too stiff to use. Never
attempt to restore workability by stirring in more water.
• Locate silver Killark box, back/top-center of unit.
• Unscrew conduit domed-cover.
Note: KILLARK® is a registered trademark of Hub bell
Incorporated, Shelton, CT, USA.
Figure 1. Sealing the Killark Box
Note: Wires must be kept separated as shown in the
Figure 2
Figure 2. Horizontal Conduit, Cutaway
• Insert fiber rope material down into horizontal conduit
opening. Pressing down firmly, work the material into the
left hub and—most importantly—being sure the material
COMPLETELY SURROUNDS THE WIRING, from the top
to the bottom, completely blocking this end of the
horizontal conduit.
Figure 3. Fiber rope material in left hub
• Insert fiber rope material down into horizontal conduit
opening. Pressing down firmly, work the material into the
right hub and—most importantly—being sure the
material COMPLETELY SURROUNDS THE WIRING, from
the top to the bottom, completely blocking this end of the
horizontal conduit.
Figure 4. Fiber rope material in right hub
• Pour sealing compound down in between the two fiber
rope dams filling the remaining space. Pour slowly, being
CAUTION: Solutions used to clean coils or
neutralize bacteria growth must not be corrosive
to metals (enamel-coated steel) and materials
used in the maintenance of this equipment—
damage can result: use a soft cloth and warm
water to clean
Left Hub Right Hub
Wiring

12 | Installation Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers
careful not to trap air bubbles. Immediately wipe off any
spilled sealing compound.
Figure 5. Adding sealing compound
• Screw conduit domed-cover back onto conduit opening.
Note: Initial setup of sealing compound will occur in
approximately 30 minutes. However, the sealing compound
requires a minimum of 8 hours above 32ºF (0ºC) to develop
sufficient strength to withstand explosions.
Note: Wires must be kept separated as shown in the figure
before addition of the sealing compound.
Electric Connection Check
Points
• Have proper connections been made at the junction
box?
• Is the junction box lid fastened tightly to the junction box?
• Are all wire connections secure?
• Are the service conductor sizes adequate to carry rated
load?
• Is the unit properly grounded?
• Is the unit connected to a properly fused branch circuit?

Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers Start-Up Procedure | 13
Start-Up Procedure
Thermostat is located at the back of the unit. Turn the knob
clockwise towards the higher numbers for colder
temperatures. Higher settings on the knob (higher numbers)
mean lower temperatures (colder) in the refrigerator.
On the coldest settings, temperatures in some spots inside
the refrigerator cabinet may drop below 32°F. Use higher
thermostat settings only when required or recommended.
To check chamber temperature, place a dial thermometer on
a shelf in the center of the chamber. Initially, rotate the
temperature control knob to an arbitrary setting. Allow
approximately 2 hours for the temperature to initially stabilize.
Check the temperature and compare with the dial setting.
Adjust dial further to reach the desired operating temperature.
After chamber initially stabilizes, allow 1/2 to 1 hour for the
chamber temperature to stabilize after subsequent
temperature adjustments.
Because the markings on the dial do not indicate specific
temperatures, use them AS REFERENCE POINTS ONLY for
any future setting of the temperature.
If the room thermostat is turned below 60ºF at night, consider
setting the temperature control one step colder. It should be
left at this setting for the night time period; return temperature
control to original setting when the room thermostat is
returned to its normal setting.
Follow site protocols for loading and unloading samples.
Restart Procedure
If unit is unplugged or turned off, allow 3 minutes before
restarting or plugging it back in.
How to Save Energy
• Be sure to follow location suggestions as mentioned in
the previous INSTALLATION section.
• Wipe moisture from glassware or other materials before
placing them in a unit.
• Don't overcrowd the unit. Too many items can increase
electrical energy demand in order to keep everything
cool.
• Close the door as soon as possible in hot, humid
weather.
• Make certain that the door is closed tightly.
• As soon as frost has accumulated to 1/4", defrost.
• Keep containers covered, when possible, to reduce
moisture buildup.
• Set operating temperature no colder than necessary for
the items being refrigerated.
Safety Tips
CAUTION: After a unit is in operation, do not
touch the cold surfaces, particularly when hands
are damp. Skin may adhere to the extremely cold
surfaces.
WARNING: Never disconnect your unit by
pulling on the power cord. Always grip the plug
securely and pull straight out from the outlet.
WARNING: Do not use a power cord that shows
cracks or abrasions. Have a qualified electrician
repair or replace damaged cords immediately.
WARNING: We recommend handling samples
by wearing gloves to avoid frost bite

14 | Maintenance Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers
Maintenance
Defrost the unit at regular intervals and unit should be
maintained and cleaned at least once a year following
instructions below.
Follow site protocols for cleaning.
Cleaning the Unit
Before beginning cleaning unit follow these instruction listed
below:
• Disconnect power cord from its outlet.
• Set the temperature control to the OFF position.
• The unit designs permit easy and rapid cleaning and
should not take more than a few minutes. Remember to
wear protective gloves to prevent frost bite, especially
when removing items from freezer units.
• Do not use abrasive scouring powders, waxes, solvents,
furniture polish, undiluted detergents or cleansers
containing petroleum products on the surfaces of units.
Cleaning Interior/Exterior/
Door Gaskets
A solution of mild soap/detergent and lukewarm water can be
used for cleaning the interior, exterior and door gaskets with a
soft, clean cloth. Rinse with clean water and dry thoroughly
before reconnecting and turning on the unit.
The cabinet interior should be cleaned frequently. Any spilled
liquid should be wiped off immediately since stains resulting
from some spills could be permanent if not quickly removed.
The most convenient time to clean the interior is after
defrosting.
Cleaning the Condenser
With forced-fan vented units, remove the screws that mount
the grill to the unit. Pull temperature control knobs straight
out. This will expose condenser for cleaning.
These surfaces may be warm to the touch. The condenser
should be cleaned before becoming clogged with dirt/dust.
Construction or other dirt causing environments may
significantly increase the required frequency. The condenser
should be cleaned at least once a year.
Manual Defrost Procedure
Use the following procedure to defrost manually:
• Rotate the temperature control knob to the OFF setting
or zero position according to the model.
• Disconnect the power cord from its outlet.
• Remove contents of the unit. If practical, wrap contents
in paper and then in a heavy blanket to maintain
temperature of items, especially those removed from a
freezer. Wear protective gloves to prevent from frost bite
when handling cold items.
• Open door and allow free circulation of ambient air.
• To speed the process, place pan of warm water inside
the chamber.
• Wipe out the interior.
• Replace the contents.
• Reconnect the power cord to outlet and set temperature
control to desired operating temperature
CAUTION: When servicing the unit, disconnect
from the electrical power source.
CAUTION: Refer servicing to qualified
personnel.
CAUTION: Never clean around the condensers
with your fingers. Some surfaces are sharp.
CAUTION: Do not use any sharp instruments,
blade or scraper to remove ice and frost on
refrigerator or freezer surfaces because of the
very real danger of puncturing the cooling coil.
CAUTION: Do not use any electrical devices to
defrost the unit.

Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers Maintenance | 15
When frost accumulates to 1/4" or more, the operating
efficiency of the unit will be affected.
All laboratory refrigerators feature automatic defrosting and in
normal conditions no manual defrosting is required. However,
in certain conditions (e.g. when the refrigerator is very full or
when any new items are stored in the refrigerator) frost may
form on the rear wall of the equipment as the compressor
must run for long periods of time. As automatic defrosting
takes place while the compressor is not running, the
refrigerator may not defrost completely before the
compressor restarts. In these instances, some manual
defrosting may be required.
Before manually defrosting the cabinet, make sure the power
lead is disconnected from the mains. With cold wall
refrigerator, condensation may form on the interior of the
cabinet and may require periodic wipe- down with an
absorbent cloth.
In high usage and/or high ambient scenarios, excessive ice
may form on the inner back wall of the refrigerator and in the
worst case or sudden power cut-off event, drain pan might
overflow. Hence it is recommended to defrost frequently and
collect any build up ice from inside in a container and safely
dispose in the sink. If the drain pan has over flowed, empty
the pan and dry up the wet regions around before next
restart.
Transportation and
Storage
Use all required local facility procedures and PPE while
transporting and storing the product.

16 | Troubleshooting Explosion-Proof and Flammable Materials Storage Laboratory Refrigerators and Freezers
Troubleshooting
This section is a guide to troubleshoot general operational problems.
Symptom Probable Cause Action
Unit does Not Run Unit Unplugged
Blown fuse or tripped circuit breaker.
Temperature control knob is turned to OFF.
Plug in Unit
Check fuse or circuit breaker at breaker box.
Turn temperature control knob to ON.
Runs Continuously Frost build up on refrigeration coils.
Dust or lint build-up on condenser.
Door gasket worn out.
Temperature too low.
Ambient temperature over 109ºF (43ºC)
Door opening frequency is high.
Defrost unit
Clean the condenser with a dry brush or
vacuum.
A leak around the door gasket will allow cold air
to escape. This causes unit to work harder than
necessary to maintain cold temperatures.
Re-seat or replace the gasket if worn.
This may cause unit to run continuously. Check
optimum running temperature.
Is the ambient air over 109ºF (43ºC), or the units
located close to heat sources? If possible,
move to a different location.
An unusually high frequency of door openings
and closings can increase operating load. Unit
will stabilize as these are decreased.
Noise problems Contents of unit set too close and rattling
against each other.
Hissing or gurgling noise is caused by
refrigerating fluid circulating.
Unit is not level on floor.
Fan noise
Rearrange contents as needed.
This is normal
Check the level of unit.
Airflow can cause this. This is normal.