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ULT Freezers

Ultra-Low Temperature Freezers & How Leasing Helps Your Bottom Line

Excedr’s leasing program is designed for labs. Request a lease estimate today and see how leasing can save you time and money.

All equipment brands and models are available.
Ultra-low temperature freezer diagram

Refrigerators and freezers keep items at low temperatures, reducing the rate of spoilage by reducing the rate of bacteria reproduction.

General lab equipment

Refrigerators and freezers work by pulling heat out of a thermally-insulated compartment providing cold storage conditions. Heat pumps, either mechanical, electrical, or chemical, are used to move hot air out, cooling the inside of the refrigerator or freezer unit. Freezers function the same as refrigerators, except they work at a much lower cryogenic temperature.

Ultra-low temperature (ULT) freezers are meant to provide long-term storage for biological samples like viruses, bacteria, enzymes, RNA, and cell cultures, but also works perfectly for reagent and vaccine storage. As the name implies, these models work at much lower temperatures than commercial freezers, ranging from -45 to -150 C depending on their intended purpose, and come in four main configurations to accommodate different lab spaces:

  • Upright
  • Chest
  • Tabletop or benchtop
  • Under-counter

You’ll find ULT freezers almost any laboratory environment, from hospitals (where cold storage facilities are often essential), biomedical facilities, and blood banks to research institutes; anywhere temperature control is paramount. That’s because sample storage at a specific temperature range is almost always a necessity when working with biological products.

Whether you are looking for a high-performance stainless steel lab freezer or are more focused on energy efficient models that provide excellent sustainability or ergonomics, there are a wide range of manufacturer choices and features options that are easy-to-use and fit your needs.

ULT Freezer Refrigeration Cycle Explained

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Ultra-low temperature (ULT) freezers are essential in any lab environment. They play a critical role in helping to ensure the safe storage of precious samples. Operating within the -46°C to -86°C range, ULTs are the perfect equipment for any lab storing analytes and products, from enzymes and drugs to biospecimen samples (such as urine, blood, tissue, cells, DNA, RNA, or protein, from humans, animals, or plants).

A ULT freezer can store hundreds of thousands of dollars in product, playing a vital role in modern laboratories by protecting samples critical to the future of their research. While lab professionals demand reliability, they must also consider storage capacity, energy usage, noise considerations and other factors that can impact their daily workflows and operational costs.

ULT freezers’ capabilities cannot be measured by one attribute alone, given the wide range of factors to consider. Instead, optimal performance is a cumulative measure of every consideration. With so many different, and highly valuable, products today, it’s critical that you research everything you need to know about ULT freezers when selecting one for your lab.

Heat Pump and Refrigeration Cycle

Refrigerators and chest freezers are able to maintain a cool interior by using a heat pump cycle or refrigeration cycle.

These cycles take heat from a source and are able to transfer it to a second location referred to as a heat sink. Depending on how it is used, a heat pump can be considered a heater if you are aiming to warm the heat sink, or be considered a refrigerator if you wish to cool the heat source.

In the case of a commercial freezer, the heat source would be the inside of the laboratory freezer unit and the heat sink would be the surrounding room that the freezer is in. The second law of thermodynamics states that in order to transfer heat work must be done.

The Carnot cycle is a theoretical cycle that demonstrates a perfect heat engine where 100% of the heat is maintained in the heat cycle system. This means that the change in temperature of the system is exactly equal to the work done by the system.

The Carnot cycle is an important tool used to determine the efficiency of freezers and refrigerators.

Vapor-Compression Cycle

The actual transfer of heat from one location to another can be done by using a working fluid to move the heat. This technique is called the vapor-compression cycle. The working fluid is cycled through a series of tubes and undergoes phase changes to absorb the heat from inside the freezer.

The fluid, commonly referred to as the refrigerant, goes through an expansion or throttle valve at high pressure and temperature. The expansion valve causes a rapid drop in pressure which results in a rapid drop in temperature.

The now cooled fluid is then cycled into the freezer compartment. A fan is used to pass air inside the freezer over the cold refrigerant which absorbs the heat, leaving behind a colder freezer compartment. The now warmer fluid is passed into a compressor that superheats the fluid and increases its pressure and the cycle starts again.

ULT freezers work in a similar fashion, only they use two cooling stages and the refrigerant used can achieve much lower temperatures than commercial refrigerants. Examples of natural refrigerants used in upright ULT freezers are methane and nitrogen.

The Carnot Cycle

Born in 1796, Nicolas Léonard Sadi Carnot was a French physicist and considered the father of thermodynamics.

Carnot’s fascination with heat and engines started early when he and his father had witnessed a steam engine in Germany. Though at the time steam engines had become widely used in the world, there had been no real scientific study done to explain how they worked.

The current theory at the time was called the caloric theory, and it stated that heat was due to an invisible liquid called caloric. This liquid would move from a hotter body to a colder body which accounted for changes in temperature.

In 1824, Carnot would publish his first and only work on the matter of heat. It was titled Reflections on the Motive Power of Fire. In it, he detailed his research on a theoretically perfect heat engine which is today referred to as the Carnot Cycle.

Carnot’s work continues to be important today as it is the basis for which much of our understanding of refrigeration and heating comes from.

We Offer Ultra-Low Temperature Freezer Leases to Fit Every Need

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Founder-Friendly Leases

Our lease agreements are founder-friendly and flexible, helping you preserve working capital, strengthen the cash flow of your business, and keep business credit lines open for expansions, staffing, and other crucial operational expenses and business development opportunities.

2-5 Year Lease Lengths

Leases range from 2 to 5 years. Length will depend on several factors, including how long you want to use the equipment, equipment type, and your company’s financial position. These are standard factors leasing companies consider and help us tailor a lease agreement to fit your needs.

Your Choice of Manufacturer

We don’t carry an inventory. This means you’re not limited to a specific set of manufacturers. Instead, you can pick the equipment that aligns with your business goals and preferences. We’ll work with the manufacturer of your choice to get the equipment in your facility as quickly as possible.

Maintenance & Repair Coverage

Bundle preventive maintenance and repair coverage with your lease agreement. You can spread those payments over time. Easily maintain your equipment, minimize the chances something will break down, repair instrumentation quickly, and simplify your payment processes.

End-of-Lease Options

At the end of your lease, you have multiple options. You can either renew the lease at a significantly lower price, purchase the machine outright based on the fair market value of the original pricing, or call it a day and we’ll come the pick up the equipment for you free of charge.

No Loan-Like Terms

Our leases do not include loan-like terms, which can be restrictive or harmful in certain situations. We do not require debt covenants, IP pledges, collateral,  or equity participation. Our goal is to maximize your flexibility. When you lease with us, you’re collaborating with a true business partner.

In-House Underwriting Process

Our underwriting is done in-house. You can expect quicker turnaround, allowing you respond to your equipment needs as they arise. We require less documentation than traditional lenders and financiers and can get the equipment you need in operation more quickly.