Ultra-Low Temperature Freezer Features

Reliable, durable, energy efficient and secure storage for your precious samples.

Our portfolio of ultra-low temperature freezers includes many valuable features that set our products apart.  Explore some of the advantages you gain when purchasing a ULT storage product that’s thoughtfully designed and robustly engineered.

Measurably High Performance

Our extensive design and engineering experience, manufacturing best practices, depth of resources and collaboration with our customers to help enable us to build high performing ULT freezers. From raw materials selection to rigorous testing and analysis of each component, we set high standards for storage system performance and inspire confidence.

Front Door Opening Recovery (DOR)

A typical ultra-low temperature freezer will be opened 2 to 4 door times per day, but in some cases, upwards of 20 times per day. Door openings place a substantial heat load burden upon the freezer.  The cooling capacity to recover from these events is critical to freezer performance. Thermo Scientific ultra-low freezers take advantage of vapor compression cycle physics to add heat absorption capacity to the liquid refrigerant entering the evaporator as part of its system design, enabling the faster Door Opening Recovery speed.

Door Opening Recovery (DOR) speed is a critical measure of freezer performance. Thermo Scientific ULT Freezers are designed to have the highest heat absorption capacity available.

Innovative compressor technology

The compressor is the heart of the ULT freezer.  As such, Thermo Scientific has developed innovative compressor technology and stands behind these components with the most comprehensive warranty available (up to 12 years). 


The Variable Drive (V-Drive) compressor, available on TSX Series freezers, delivers a leap forward in performance and energy efficiency. Where standard compressors operate in a full power or nothing format, the innovative V-Drive runs at variable speeds as required to achieve both optimal cooling capacity, as well as energy efficiency. Combined with an automated tuning control, the V-Drive compressors adjust cooling power to precisely meet the needs required by temperature conditions inside and outside of the unit. The result is better temperature uniformity, longer life of the unit and exceptional energy efficiency.

Variable Speed Compressor technology and adaptive control quickly and efficiently brings temperature back to set point, even with many door opening events in a busy lab.

Smarter cabinet design

With over 70 years of experience in manufacturing ultra-low temperature freezers, you can be sure that every detail of our freezer cabinets has been optimized for performance. Starting with the selection of only top materials, our freezers are constructed of rugged galvaneel or optional stainless steel interiors. Stainless steel shelves are both adjustable and reinforced to hold up to 125 pounds each. Thoughtful compartmentalization maximizes storage capacity and utilizes inner doors that reduce frost and ambient temperature impact. Outer doors and panels achieve exceptional R-value insulation rating via vacuum panels with water blown foam insulation. Airtight closures are assured with triple point seals around door apertures. Finishing touches include integrated control panels, easy access to filter maintenance compartments and castors that make day-to-day use intuitive and easy. And it’s all delivered in a package that optimizes sample storage per square foot and cooling capacity. 

Excellence in temperature performance over time

True performance is measurable. Thermo Scientific ULT freezers achieve consistently excellent ratings when measured by temperature peak variability, temperature uniformity and temperature stability. Using sensors throughout the cabinet under rigorous, real-world testing environments, we measure temperature fluctuations in the cabinet (Peak Variability), the consistency of those measurements over a time period (Uniformity) and temperature variations in specific locations inside of the freezer (Stability). Together, you gain assurance that your samples are consistently, securely and properly stored for the long-term.

Performance Data

Reliable sample storage

Our ultra-low temperature freezers are designed and built with the understanding that your samples are priceless and irreplaceable. That’s why reliability is the core feature across our portfolio of ULT storage products. We start with the highest quality components, such as advanced compressors and construction materials, then add end-to-end options for redundancy and monitoring systems to help ensure the safe, secure and reliable long-term storage of your precious samples. Confidence starts here.  

Secure storage

Lock compatible doors enhance the security of your samples. When a standard padlock is not practical, integrated access key security system options on our ULT freezer doors allow you to define who has access to your samples and even monitor who opens the freezer door, when and how long the door is open to help ensure strict security and safe storage.

Failsafe emergency backup cooling

Thermo Scientific ULT Freezers are built to the highest standards of dependability, but our obsession with reliability doesn’t end there.  Optional emergency LN2 and CO2 cooling systems prevent thawing and help ensure the viability of your samples in the extremely unlikely event of primary cooling system outage.

The right fit for your lab

When selecting a ULT Freezer, there’s a natural tendency to focus on the how well the unit works with regard to the basic function of keeping your samples safely and securely stored. But after decades of collaboration with our customers in their labs, we know that another important consideration is “how well does the product work for me?” After all, your ULT freezer will play an important role in your day-to-day processes, working shoulder to shoulder with you for years to come. Thermo Scientific ULT Freezers incorporate thoughtful design features that make them welcome additions to your lab. Consider:

Optimized storage space

Thermo Scientific ULT Freezers utilize an advanced vacuum-insulated cabinet walls to increase interior space, with a standardized rack, tray and box storage configuration that allows for optimum storage in the smallest possible footprint. Choose from sizes that store 300, 400, 500, 600, or 700 2-inch boxes.

Standardized rack and box configuration maximizes cooling capacity and storage space.

Ergonomic design

You’ll like the confidence you gain in the viability of your samples, but you may love the freezer itself once you start using it. Through years of design collaboration and testing with our customers, we’ve incorporated some notable features such as an ergonomic, smooth operating handle, well-balanced doors and intuitive, easy to see and read control panels. What you won’t notice is noise. Our TSX freezers operate below 50 decibels – about the same as a modern household refrigerator.

Ergonomic door handle, well-balanced door and vacuum release makes door opening and secure closing easy.

User controls are intuitive, at eye level and easy to read. Integrated USB port eliminates the need for separate data recorder.

Energy efficient and sustainable

Perhaps the greatest advantage of Thermo Scientific ULT Freezers is their ability to deliver top performance and reliability without sacrificing energy efficiency or sustainability. All TSX Series freezers are manufactured in a zero-waste facility (93% recycle and 7% waste to energy). We manufacture with natural refrigerants and water-blown foam insulation, compliant with the U.S. EPA’s Significant New Alternatives Policy (SNAP), the European Union’s F-Gas compliance and other sustainability standards. Energy efficiencies are achieved through advanced compressor and cooling systems consuming as low as 8.7 kW-hr/day - a 70% reduction compared to conventional freezers, and reduced heat output for HVAC savings in the lab.

The manufacturing facility where Thermo Scientific TSX Series ULT Freezers are produced achieved zero waste to landfill in 2014.

Built to last

Enduring, comprehensive warranty

Thermo Scientific stands behind its ULT freezers like no other manufacturer, offering a comprehensive 5-year warranty on parts and labor, plus an additional 7 years on our V-Drive compressors. That’s a full 12 years of unparalleled confidence in your purchase. We take your sample viability as seriously as you do.

Hassle-free issue resolution

If there ever is a problem with your Thermo Scientific ULT Freezer, we strive to quickly and easily resolve it. Thermo Scientific customers enjoy access to the largest network of lab equipment service professionals on the globe, with fast response times, remote service and problem resolution and a track record of service excellence over 50 years long. We want to provide minimal downtime in the unusual event that you experience a problem. Dependable compliance and preventative maintenance programs make ownership truly care-free.

Connected solutions

Our ULT freezers are fully compatible with the Thermo Scientific connected solutions portfolio. Whether it’s your goal to protect and monitor the contents of your ULT freezer with custom alarms and notifications, create an audit trail with 21 CFR 11 reporting or manage fleet energy usage and performance with advanced analytics, we have you covered.

Additionally, TSX Series ULT freezers come with embedded DeviceLink technology that allows you to enable Smart-Connected Services, a convenient and affordable 24/7/365 remote monitoring as a service offer where trained professionals watch over equipment helping to ensure sample integrity for you.