OWNER’S GUIDE

Undercounter & Mid-Size Laboratory Refrigerator & 

Freezer with Temp Display System V5.2

Table of Contents

RECEIVING AND SHIPPING DAMAGE HANDLING............................................... 2

SAFETY ............................................................................................................... 3

RELEASE OF LIABILITY ........................................................................................ 3

ELECTRICAL INFORMATION............................................................................... 4

INSTALLATION.................................................................................................... 5

OPERATION........................................................................................................ 7

Quick Troubleshooting Guide.......................................................................... 11

Maintenance and Cleaning.............................................................................. 14

Hydrocarbon Service Notes............................................................................. 15

Factory Warranty Policy .................................................................................. 16

PN: 21634 Rev. 2-18-2018
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Each refrigerator or freezer is carefully inspected to meet our high standard quality 

assurance policy, before it ships to you. Unfortunately, shipping damage can happen 

during transportation to you. There are two general types of shipping damage. The first 

is visible damage. This type of damage includes visible loss, damage, shortage or any 

external evidence of loss or damage that is visible at time of delivery. This type of 

damage must be noted in detail on your delivery receipt. Make sure the driver signs 

and dates the delivery receipt, acknowledging the damages. We also recommend 

taking many pictures to demonstrate and document the damaged area(s). This must

happen at the time of delivery or it won’t happen at all. Keep a copy for your records 

and send another to the carrier’s damage claims department along with a formal 

request for an inspection report. Follow up with a phone call. Their contact information 

can be found on the carrier’s web site.

The second type of shipping damage is concealed damage. This type of damage will 

probably not be apparent at time of delivery and may not be discovered until 

unpacking and inspecting the unit. Remember, time is of the essence here. You should 

unpack and inspect the unit as soon as possible. Each day that passes reduces the 

likelihood that the carrier will pay the claim. As soon as the concealed damage is 

discovered, stop unpacking and retain all packing materials. Take many pictures to 

demonstrate and document the concealed damage area(s). Contact the carrier by 

phone to report the claim. Note the date and time and person you spoke with. Get a 

claim number. Follow up with a written letter referencing the claim number and 

including a formal request for an inspection. Again, consult the carrier’s website for 

specific claim instructions and follow them precisely.

AS STATED ABOVE, THE CARRIER IS YOUR SOLE SOURCE FOR SATISFACTION OF 

A DAMAGE CLAIM. UNDER NO CIRCUMSTANCES SHOULD THE MERCHANDISE BE 

RETURNED TO THE MANUFACTURER. NO RETURNS WILL BE ACCEPTED WITHOUT 

PRIOR AUTHORIZATION.

RECEIVING AND SHIPPING DAMAGE HANDLING
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For your safety

• DO NOT store any unsealed chemical material in this refrigerator orfreezer. 

Corrosive fumes from chemical material can linger inside of the chamber 

and cause serious damage to the refrigeration coils. Storing unsealed 

chemical material in this equipment will void the factory productwarranty.

• DO NOT store or use gasoline, or other flammable liquid in this refrigerator 

or freezer. This equipment is not rated to be a flammable materialstorage.

• DO NOT operate this equipment in the presence of explosive fumes. This 

equipment is not rated to be a hazardous locations refrigerator orfreezer.

We offer flammable material storage and hazardous locations refrigerators and/or 

freezers for your application. Please contact your local sale representative for more 

information.

Before you start to use this refrigerator, please take a moment to:

• Connect your remote alarm contacts system, or auto dialer, to the

refrigerator’s alarm system (if any).

• If your refrigerator model does not have an alarm system, you can 

install your 3rd party alarm into our refrigerator via the 3/8” access 

porthole. Please see “Field Monitor Probe Installation” Section.

• Develop an emergency backup plan and designate a different 

refrigerator or freezer to store the contents, if this refrigerator has an 

unforeseen issue.

IF YOU PLAN TO STORE IRREPLACEABLE AND/OR HIGH VALUE PRODUCTS IN 

THIS UNIT TAKE THE PROPER PRECAUTIONS NOW.

SAFETY

RELEASE OF LIABILITY
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The manufacturer’s sole obligation under this warranty is limited to either repair or 

replacement of parts, subject to the additional limitations below. This warranty 

neither assumes, nor authorizes any person to assume obligations other than those 

expressly covered by this warranty.

NO CONSEQUENTIAL DAMAGES. The manufacturer is not responsible for economic 

loss, profit loss, or special indirect or consequential damages, including without 

limitation, losses, or damages arising from contents spoilage claims whether

because of refrigeration or mechanical failure.

• The supply circuit to this cabinet must 

conform to NEC (National ElectricalCode). 

Consult the cabinet Serial-Data plate for 

voltage, cycle, phase, and amp 

requirements before making connection.

• SUPPLY VOLTAGE SHOULD NOT VARY 

MORE THAN 5% FROM SERIAL PLATE 

RATINGS.

• DO NOT connect this equipment to a GFI 

(Ground Fault Interrupt) circuit.

• Do not use an extension cord or any multioutlet strip or plug. Using such devices can lead to insufficient power, and lead 

to component failure, such as the compressor or starting components.

• If the power cord is damaged, it should be replaced immediately by an 

authorized service technician.

• Be sure your unit is properly grounded. Use the 3-prong plug provided into a 3-

prong grounded outlet. Unless the above grounding method is followed, youare 

not protected against severe or lethal shock in the event of a short circuit of an 

electrical component or wiring of the unit.

ELECTRICAL INFORMATION
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Please take a moment to follow the steps below, before using this equipment.

1. Find a suitable location to install this refrigerator (or freezer)

2. Level this refrigerator (or freezer)

3. Set up the shelves inside (if applicable)

4. Install the optional monitor probe for field installation

5. Ready to use

1. SUITABLE LOCATION

Ambient Temperature – Unlike a household refrigerator, this equipment is designed 

for scientific / medical application. Many components are heavy duty and extra

sized, to meet the ultimate temperature performance. Therefore, the sounds 

generated from its operation may not be accepted by everyone in the room. Please 

take the operation sound factor into consideration and locate this refrigerator 

accordingly.

Please ensure the ambient temperature is climate-controlled, between 65°F to 85°F, 

to achieve the ultimate temperature performance.

Clearance Space – We require 2 to 3 inches of clearance space around the refrigerator. 

So, it would be easier to remove the refrigerator for annual maintenance, or service.

INSTALLATION
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2. LEVELING

Once this refrigerator or freezer is at its final location, please level your refrigerator, 

because it is critical to equipment operation. Here are a few benefits to a good leveled 

refrigerator (or freezer):

1. Moving mechanical parts,such asfan or compressor, would have less chances 

to fail, since it is in the designed upright position.

2. Reduce noise.

3. Door(s) would close properly.

4. Condensate water would flow out the refrigerator properly.

To level this equipment, set a leveler in each corner on the top. If the equipment is not 

level, adjust either the leveling legs or casters.

We recommend to slightly tilt the refrigerator (or freezer) toward to the back, 

about 5 degrees. So, the non-self-closing door can be shut properly, and condensate 

water would flow out easier.

3. (OPTIONAL) MONITOR PROBE FOR FIELD INSTALLATION

Each refrigerator or freezer is equipped with a 3/8” probe access port hole for your 

independent probe installation. The port hole is generally located in the back of your 

refrigerator (or freezer). Simply remove the white caps, run your probe through, and 

seal the hole with electrical putty to prevent air from getting into the chamber.

DO NOT run your probe through the door gasket, as it may cause serious 

condensation or a frozen evaporator issue. The port hole is specifically designed to 

allow you to install the monitor probe.

4. READY TO USE

Once you ensure the electrical service is adequate and Steps 1 to 3 are followed, you 

are ready to use this refrigerator (or freezer). Simply plug in the power cord into the 

wall outlet.

This refrigerator (or freezer) is factory set to run at its ultimate temperature 

performance. There should not be a need to adjust the temp settings. If you feel the 

temp settings must be adjusted, please refer to “TEMPERATURE ADJUSTMENT” section 

in this manual for more details.
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Temperature Controller System

Product Description

The digital microprocessor temperature controller is designed to provide temperature 

control of refrigerators or freezers. The controller also provides a constant readout of 

the sample temperature inside of the unit. A touch keypad allows the user to easily 

select the display units, set point, and differential set point.

Please Note: The digital temperature controller has been factory 

set and tested to allow your unit to operate at its desired 

temperature cycle.

Adjusting the settings on the controller will alter these factory 

settings. WE STRONGLY RECOMMEND YOU CONTACT THE

MANUFACTURER’S TECHNICAL SUPPORT DEPARTMENT BEFORE 

MAKING ANY ADJUSTMENTS TO THIS CONTROLLER. TECH SUPPORT 

PHONE NUMBER IS (800) 648 4041, SELECT THE OPTION FOR 

TECHNICAL SERVICE.

OPERATION
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CHECK TEMPERATURE HISTORY

Press and release [UP] button. The display will show the maximum temperature ever 

reached since the last reset.

Press and release [DOWN] button. The display will show the minimum temperature 

ever reached since the last reset.

Press and hold [SET] for more than 3 seconds, while the maximum or minimum temp 

is displayed. (rSt message will be displayed).

CHECK THE SET POINT

Press and release [SET] button. The display will show the current set point value.

Operation

During the normal operation, the refrigerator’s (or freezer’s) compressor would turn 

on and off, to maintain the cold temperature in the storage chamber.

In this controller, the point where the compressor is cut off is called “SET POINT”. 

The point where the compressor is turned on is calculated by adding the value of 

“SET POINT” and “Hy” (temp differential).

For example, if you wish to maintain the operation temperature between 3°C and

7°C, you would set “SET” = 3°C, and “Hy” = 4°C.

“ALU” is the high temp alarm point, and “ALL” is the low temp alarm point. Both 

alarm settings will alert users when the refrigerator’s (or freezer’s) temp is out of 

range, via visual & audible alarm, and remote alarm contact.
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“US” is the upper setting limit, and “LS” is the lower setting limit. Both limit settings

will prevent users accidentally adjust “SET”, “ALU”, or “ALL” outside the range.

CODE DESCRIPTION FACTORY SETTING

SET Temp set point (compressor off point) 3°C or 38°F (refrigerator)

-24°C or -12°F (freezer)

Hy Temp differential between compressor 

start and off point

3°C or 5°F (NOT 

RECOMMENDED TO

CHANGE)

ALL Low temp alarm point 1°C or 34°F (refrigerator)

-28°C or -18°F (freezer)

ALU High temp alarm point 10°C or 50°F (refrigerator)

-15°C or 5°F (freezer)

Lod Screen display choice (air or sample probe) P3

CF Celsius & Fahrenheit unit change

O3 Sample (display) probe calibration / offset 0

OT Air (control) probe calibration / offset 0

US The maximum limit that SET or ALU could

reach

10°C or 50°F (refrigerator)

-10°C or 14°F (freezer)

LS The minimum limit that SET or ALL could

reach

1°C or 34°F (refrigerator)

-30°C or -22°F (freezer)

Change the set point (compressor turn-off point)

Press and hold [SET] until °C or °F icon blinking. Press [UP] or [DOWN] to change the 

setting value. Then, press [SET] once to confirm the new setting.

Change the other settings

Press and hold both [SET] and [DOWN] at the same time until “Hy” appears on the

display.

Press [UP] or [DOWN] to scroll different settings. Press [SET] to enter the setting. 

Press [UP] or [DOWN] to change value. Press [SET] once to confirm the new setting. 

The display will show the next setting.

At any setting, press and hold both [SET] and [UP] to exit out the setting mode, or 

simply leave the display alone for 10 seconds.
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Change the readout from °C to °F, or °F to °C

Press and hold the [LIGHT] icon button for 5 seconds. The controller will restart and 

change the display scale from °C to °F, or °F to °C.

Advanced Settings – for service technician only

ATTENTION: This section is for service technicians or experienced users 

only. Altering the following settings can result in malfunction or inaccurate 

temperature readout.

Air and Sample Temperature Display

The controller has the capability to display either the air or sample temperature 

readout. For the normal operation, the sample-simulated temperature (P3) is 

displayed to provide users the content temperature. For the actual operation, the 

air temperature (P1) is used to control the compressor’s cycle.

This is a useful tool for you to make a precise adjustment, or temperature validation 

process.

“Lod” setting allows you to display either air (P1) or sample (P3). Press and hold both

[SET] and [DOWN] at the same time until “Hy” appears on the display.

Press [UP] or [DOWN] until “Lod” shows up. Press [SET] to enter the setting. Press

[UP] or [DOWN] to toggle between the air temp “P1”, or the sample temp “P3”. 

Press [SET] once to confirm the new setting. The display will now show the temp you 

have selected.

We strongly recommend you change the “Lod” setting back to “P3” 

before you complete the service. This will allow users to see the samplesimulated temperature, and the controller will be able to alert when the 

sample temp is out of range.

Calibration / offset

“OT” setting allows you to change the air probe’s calibration. “O3” setting allows you 

to change the sample probe’s calibration.

Please be sure you have a NIST traceable and calibrated thermometer. Place your

thermometer’s probe next to our sensor accordingly, air vs. air, or sample vs. sample,

before making an adjustment on either “OT” or “O3”.
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For more advanced settings, please contact our Technical Service Department for 

assistance. (800) 648 4041, select the option for Technical Service.

Check these items before calling for service

PROBLEM: POSSIBLE CAUSE / SOULTIONS:

Unit does not run • Electrical circuit is not 110-120V 60Hz.

• The power cord is not plugged in.

• No power at electrical outlet. Check tomake 

sure breaker is not tripped or fuse is not

blown. Additionally, make sure unit is not

plugged into a Ground Fault Circuit Interrupter 

(GFCI) type of outlet.

Unit does not 

maintain at the 

proper 

temperature

• Check the room temperature. We recommend 

the refrigerator or freezer should be placed in 

an air-conditioned room between 65°F to 

85°F. If the room temp is too warm, the 

refrigerator or freezer may not be able to 

maintain the interior temp at proper range.

• Door is not closed properly.

• Amount of stored product is overloaded.

• Product replacements are pushed againstrear 

wall or interrupted the proper refrigerator air 

circulation. For the proper air circulation, 

place the products evenly on each shelf. Do 

not push against the refrigerator’s rear orside 

walls.

• Evaporator is blocked by frost or ice. Remove 

the products, unplug the refrigerator or 

freezer power, and allow the unit to defrost. If 

the problem still exists, call forservice.

• 3rd party thermometer is placed incorrectly. 

For proper temperature monitoring, the 

thermometer should be place in the middle of 

refrigerator.

PLEASE NOTE! Prior to shipment, each refrigerator and 

freezer has been calibrated and tested at proper 

temperature range.

Quick Troubleshooting Guide
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• Prolong door openings.

• Control set too cold.

Room temperature is high which will make the 

unit work harder to keep cool.

Unit does not 

maintain at the 

proper temperature

• The exterior walls can be as much as 30 

degrees warmer than room temperature due 

to the embedded condenser coils. Thisis

normal when the unit is operating.

Appliance runs too long • Compressor may be overheated. Please check 

the room temp and ensure the range is within 

65°F to 85°F. If the problem still exists, callfor

• service.

Temperature of external 

wall surface is warm

• The exterior walls can be as much as 30

degrees warmer than room temperature due

to the embedded condenser coils. This is

normal when the unit is operating

Compressor noises • Compressor may be overheated. Please check

 the room temp and ensure the range is within

 65°F to 85°F. If the problem still exists, call for

 service.

Moisture collects

inside or on outside 

surface

INSIDE:

• Door gasket is not sealing properly. Check for 

debris, cracks, and items passing through door 

at the gasket.

• The refrigerator or freezer is facing a doorway 

or is underneath of air conditioning vent. 

Relocate the unit or redirect air vent.

• Too many door openings. Minimize time door 

is open.

• Hot, humid weather increases condensation.

• Make sure there is a water trap (U-shaped 

loop) in the drain tube near the compressor. 

This will “trap” a small amount of water in the 

loop and prevent air from entering the

 chamber through the tube.

OUTSIDE:

• Hot, humid weather increases condensation.

• As humidity decreases, moisture will disappear.
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Odor inside the unit • Interior needs to be cleaned. See section on 

maintenance and cleaning in this manual.

• Make sure product containers are

tightly sealed to prevent leakage

Door will not 

Close

• The unit is not level. Refer to the Leveling 

section at the beginning of this manual

• Check for dirt and debris or items

passing through the door seal.

MOISTURE DURING THE SUMMER SEASON

The amount of moisture, condensation, or high humidity related issues increase 

during the summer and, in most cases, will self-resolve when the weather cools 

down. Please note a refrigeration system will NOT generate moisture or water but 

simply condenses the moisture that is already in the chamber. Keeping the unit in an 

air conditioned, low humidity space will resolve many issues. Other things you should 

check

1. Location of the refrigerator (See Quick Troubleshooting Guide above)

2. Door sealing and frequency of door opening event (See Quick Troubleshooting 

Guide above)

3. Make sure there is a water trap (U-shaped loop) in the drain tube near theend 

This will “trap” a small amount of water in the loop and prevent air from enter 

the chamber through the tube.

BEFORE CALLING THE MANUFACTURER’S TECHNICAL SUPPORT DEPARTMENT,

please have the unit’s model and serial number ready as well as the problem

description. The model and serial number is located on the serial tag which can be 

found on the interior left upper wall of the unit.
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CLEANING

PART CLEANING AGENTS TIPS AND PRECAUTIONS

Interior 

and Door 

Liners

Soap and water 

Baking soda and 

water

Use 2 tablespoons of baking soda 

in 1 quart of warm water

Be sure to wring excess water out 

of sponge or cloth before cleaning 

around controls, light bulb or any

electrical parts.

Door 

Gaskets

Soap and water Wipe gaskets and their seating 

surfaces with a clean soft cloth

Shelves Soap and water Do not wash removable shelves in 

dishwasher

Exterior 

and 

Handles

Soap and water 

Non-Abrasive

Glass Cleaner

Do not use commercial household 

cleaners, ammonia, or alcohol to 

clean handles

Use a soft cloth to clean smooth 

handles

Do not use a dry cloth to clean

smooth handles

Clean the glass with a mild detergent and water on a soft cloth or sponge. Rinse with 

water and wipe dry.

For Swinging door units, pay attention to the gasket and itsseating surfaces. Any debris 

buildup on these can cause air leaks into the compartment resulting in condensation 

as well as reduced efficiency.

Maintenance and Cleaning
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According to U.S. Code of Federal Regulation 40 Part 82, this refrigerator 

employs the natural refrigerant, specifically hydrocarbon, R290 or R600a.

Because of the nature of hydrocarbon refrigerant, for mechanical repair, such 

asrecharge the refrigerant, or compressor replacement,should only be carried 

out by a certified refrigeration technician.

The safety of this equipment is listed by Underwriter Laboratory (UL) under 

Standard 471, Section SB – “natural refrigerant.”

Horizon Scientific, Inc. warrants to the original purchaser every new Horizon Scientific, Inc. 

refrigerated unit, the cabinet and all parts thereof, to be free from defects in material or 

workmanship, when such unit is installed, used, and maintained in accordance with 

provided instructions, for a period of two (2) years. The warranty period starts two weeks 

from the date of shipment from Horizon Scientific, Inc. This two-week period allows ample

shipping time so that the warranty will go into effect at approximately the same time your 

equipment is delivered. Unless subject to prior written agreement with Horizon Scientific, 

Inc., this warranty does not allow for any warranty start deferment greater than two weeks 

from date of shipment due to a delayed installation and/or start-up. By purchasing any 

product from Horizon Scientific, Inc., you and any entity for which you are purchasing

acknowledge and agree to each provision contained herein, and all other Notices and Terms 

provided to Purchaser by Horizon Scientific, Inc., which are hereby incorporated.

Under this warranty, Horizon Scientific, Inc., through its authorized service organizations, 

will repair, or at its option, replace any part found to contain a manufacturing defect in 

material or workmanship without charge to the owner for parts and service labor. 

Replacement or repaired parts will be warranted for only the unexpired portion of the 

original warranty. Horizon Scientific, Inc. will not assumeany shipping or cartage costs for 

parts under warranty. These costs shall be paid by the customer.

NO CONSEQUENTIAL DAMAGES. Horizon Scientific, Inc. is not responsible for economic 

loss; profit loss; or special, indirect or consequential damages, including withoutlimitation,

losses or damages arising from contents spoilage claims regardless of refrigeration failure, 

electrical failure, power failure, or compressor failure. HORIZON SCIENTIFIC, INC.’S 

MAXIMUM CUMULATIVE LIABILITY RELATIVE TO ALL CLAIMS AND LIABILITIES, INCLUDING 

OBLIGATIONS UNDER ANY INDEMNITY, WHETHER OR NOT INSURED, SHALL NOT EXCEED 

THE COST OF THE PRODUCT(S) GIVING RISE TO THE CLAIM OR LIABILITY.

WARRANTY IS NOT TRANSFERABLE. This warranty is not assignable and applies only in 

Factory Warranty Policy

Hydrocarbon Service Notes
P a g e | 16

favor of the original purchaser/user to whom delivered. Any such assignment or transfer

shall void the warranties herein made and shall void all warranties, express or implied, 

including any warranty of merchantability of fitness for a particular purpose. NO IMPLIED 

WARRANTY OF MERCHANTABILITY OF FITNESS FOR A PARTICULAR

PURPOSE. There are no other warranties, express, implied, or statutory, except the two (2) 

year warranty as described above. These warranties are exclusive and in lieu of all other 

warranties, including implied warranty and merchantability of fitness for a particular 

purpose. There are no warranties which extend beyond the description on the face hereof, 

whether based on contract, warranty, tort (including negligence), strict liability, indemnity, 

or any other legal theory, and whether arising out of warranties, representations, 

instructions, installations, or non-conformities from any cause. Purchaser further

acknowledges that the purchase price of the Product reflects these warranty terms and

remedies.

ALTERATION, NEGLECT, ABUSE, MISUSE, ACCIDENT, DAMAGE DURING TRANSIT OR 

INSTALLATION, FIRE, FLOOD OR OTHER EXTERNAL CAUSES.

Horizon Scientific, Inc. is not responsible for the repair or replacement of any parts that 

Horizon Scientific, Inc. determines have been subjected after the date of manufacture to 

alteration, neglect, abuse, misuse, accident, damage during transit or installation, fire, flood 

or other external causes. It does not apply to defects resulting from failure to properly 

install, operate or maintain the product in accordance with the printed instructions 

provided, or damage caused by the storage of any corrosive material that comes in contact 

with the interior or exterior portions of the cabinet, or the use of spark producing 

equipment or containers (such as galvanized or carbonized steel containers) that come in 

contact with any interior portion of the cabinet.

OUTSIDE U.S./CANADA. This warranty does not apply to, and Horizon Scientific, Inc. is not 

responsible for, any warranty claims made on products sold or used outside the United 

States and Canada.

CHOICE OF LAW/VENUE. The laws of the State of South Carolina shall govern the validity,

interpretation and enforcement of this warranty, regardless of conflicts of law principles. 

Purchaser agrees that proper venue for any action to enforce the terms of this warranty

shall be the Dorchester County District Courts, South Carolina. Purchaser submits the 

jurisdiction of such courts over the Purchaser and the subject matter of any such action. 

Any action for breach of these warranty provisions must be commenced within one (1) year 

after that cause of action has accrued.

WARRANTY CLAIMS. To obtain prompt warranty service, simply contact the manufacturer 

at 800-648-4041. Horizon Scientific, Inc.’s shipping records showing date of shipment shall 

be conclusive in establishing the warranty period. All claims should include: model number 

of the refrigerator, the serial number of the cabinet, proof of purchase, date of installation, 

and all pertinent information supporting the existence of the alleged defect. Any repairs

must be authorized by Horizon in order for the warranty to be honored.