5 Tips to Help You Select the Right ULT Freezer

Contributed by PHC Corporation of North America

Ultra-low temperature (ULT) preservation lab equipment plays a vital—although often overlooked—role in protecting valuable research and products. If this equipment fails, the consequences can be catastrophic, with years of research potentially destroyed and life-saving treatments lost.
 
To reduce the risk, it’s important to procure the right ULT freezers. And that means applying appropriate scrutiny when evaluating and selecting a new unit. But what does that look like in practice? What should you pay attention to in order to help maximize your chance of securing a fit-for-purpose ULT freezer that you can be confident in?
 
Here, we summarize our five top tips to help you select the right ULT freezer.
 
1. Be clear on capacity requirements and space
 
First, you will need to know exactly how much storage is needed and how much floor space is available within your lab to house ULT units. No matter how good your ULT freezer is, if it can’t fit in your lab or store all the necessary inventory, then it won’t be much help. A range of ULT units are available on the market to meet a variety of capacity and floor space requirements, from high-volume products ideal for bulk storage to slim upright or chest units that maximize capacity in a small footprint.
 
Additionally, keep in mind that many ULT freezers need a certain amount of clearance at the front and back of the unit to allow for adequate ventilation, which may catch some people off guard when planning how units fit into their lab space. Some ULT freezers, however, do not have any ventilation clearance requirements for the left and right sides of the equipment. Be sure to plan for ventilation requirements from the start.
 
My Green Lab and the I2SL organize a free annual competition called the International Laboratory Freezer Challenge, which emphasizes sustainable lab cold storage management, including ULT freezers. The competition promotes efficient inventory management, offering tools like sample management templates. Applying these practices helps ensure you don’t over-purchase capacity, helping optimize both freezer selection and utilization.
 
2. Prioritize reliability
 
The impact of frequent ULT freezer breakdowns and repairs is hard to overstate—from a higher-than-anticipated total cost of ownership and increased risk of ruined samples and products, to severe operational disruption. It’s no surprise, then, that reliability should be top of mind in your ULT freezer search.
 
Many ULT freezers are designed with technologies to ensure smooth operation throughout their lifecycle, such as backup systems that maintain functionality during service events.
 
While checking features is important, to maximize the chance of selecting the most reliable equipment, we recommend looking for ULT freezers from equipment providers with a strong reputation and reliability. Consult colleagues or repair technicians for insights on frequently failing models, and browse forums for additional feedback (keeping in mind such sources may vary in reliability).
 
The ability of a ULT freezer to maintain a uniform temperature and recover quickly after door openings is essential for preserving sample quality. These performance metrics are important when selecting a ULT freezer.
 
Understanding and comparing temperature uniformity and recovery claims, however, isn’t always easy: testing practices and conditions can understandably vary on account of the lack of standardized industry guidance, claims may cover product families rather than individual units, and definitions can sometimes be unclear. For example, differences in ambient testing temperatures, chamber fullness, or the number of temperature probes used can affect results. It can lead to different temperature gradients between the unit interior and the exterior environment, and, consequently, different temperature deviations and recovery times, even when the door is open for the same duration.
 
That said, ENERGY STAR® testing results (if a company has them) can help provide an unbiased one-to-one comparison of temperature recovery results. To help with comparisons, ENERGY STAR® and ACT Ecolabels offer independently verified data on performance and energy efficiency. Reviewing these certifications can help provide clarity and confidence when evaluating freezers. You can review the ENERGY STAR testing results for ULT freezers in ENERGY STAR’s regularly updated spreadsheet of test results.
 
4. Pay attention to the potential lifetime cost of equipment
 
Budget restrictions can all too often influence purchasing decisions for equipment such as ULT freezers. But while choosing a lower-cost (and potentially lower-quality) ULT might help reduce capital expenditure and help purchasing teams meet spending goals on paper, it could, in fact, lead to a much higher cost overall.
 
For example, evaluate additional charges for maintenance and warranty coverage for parts and labor. Perhaps most importantly, though, you should consider the potential impact of more frequent breakdowns on your lab—including the time researchers have to take away from research to transfer samples to a working unit. Frequent breakdowns can necessitate early replacement, significantly increasing expenditure.
 
In many cases, investing in higher-quality ULT freezers with a balance of reliability and affordability is more cost-effective over time. To help minimize lifetime costs, the Freezer Challenge encourages implementing proper freezer maintenance protocols, such as defrosting and temperature monitoring, to extend the operational life of the equipment and prevent unexpected expenses.
 
5. Scrutinize sustainability credentials
 
Reducing the environmental impact of research is becoming an increasing priority for many labs. But it’s not just the planet that benefits from greener ULT freezer technology and design—laboratories do too.
 
Unsustainable ULT units can negatively impact your lab in ways that aren’t always obvious. For example, ULT units that consume more electricity to maintain the same level of performance likely expel relatively more heat into the lab space, which can put more stress on HVAC systems, as well as increase the temperature recovery time of the ULT unit (owing to a larger difference between the ULT chamber temperature and the ambient temperature). The elevated strain on both the HVAC system and the ULT unit may even lead to premature failure, which can be costly and disruptive.
 
Before making a purchasing decision, thoroughly review a freezer’s sustainability and energy efficiency claims. Independent certifications like ENERGY STAR® provide trusted performance and energy consumption data, helping you compare products. ACT Ecolabeled products also offer additional environmental impact insights. Together, these tools ensure you select a freezer that balances performance, efficiency, and sustainability, supporting your lab’s operational and environmental goals.
 
Making the right decision when it comes to ULT freezers
 
Selecting the right ULT freezer is crucial for preserving valuable samples and minimizing risks. To maximize the chance of making the right decision for your lab, be sure to consider your capacity requirements and available floor space. Also keep in mind the unit’s reliability, temperature recovery, and uniformity performance, the potential lifetime cost of the purchase, and the unit’s energy efficiency.
 
By thoroughly assessing these factors, you can select a dependable unit that supports your lab’s operations while mitigating potential disruptions. Resources like the International Laboratory Freezer Challenge, which provides tools for inventory management and energy efficiency insights, can further support your decision-making process. 
 
A note from our sponsor and the author of this article:
 
To help labs make informed decisions about ULT freezers, PHCbi offers a range of advanced options designed for reliability and performance. The TwinGuard® Series features dual refrigeration systems that work independently to maintain ultra-low temperatures, ensuring sample integrity even during service events.
 
Additionally, PHCbi ULT freezers, including the VIP® ECO freezers, use innovative heat exchanger technology to provide uniformity and stability, even in high ambient temperatures. Unlike many ULT models, all PHCbi brand ULT freezers do not require ventilation clearance on the sides, allowing for more flexible placement in the lab.
 
PHCbi also emphasizes sustainability, with ENERGY STAR®-certified freezers that combine efficiency with performance.
 
Learn more about PHCbi’s ENERGY STAR® Certified Preservation Products or register for a lunch-and-learn session to explore how these freezers can meet your specific needs.