Cryogenic Freezer Maintenance Services

cyogenic freezer maintenance

Princeton CryoTech is a leading national distributor for liquid nitrogen freezers and biomedical storage equipment.

We pride ourselves in our past 27 years of selling and servicing MVE, earning the trust of our customers since 1990.

We don’t consider ourselves freezer salespeople, we consider ourselves technicians and engineers who happen to sell cryogenic storage equipment. Where others are quick to sell and move on, Princeton CryoTech creates lasting relationships with clients who value ongoing service and support. Everything we sell automatically comes with lifetime technical support, and discounted preventative maintenance and service contracts.

Be careful who you reach out for assistance servicing your cryogenic freezer. Many companies claim knowledge in this field, but an uninformed service call can often leave your freezer worse off than it started. When someone quotes you an expensive repair, don’t hesitate to ask us for a second opinion. Sometimes a seemingly serious issue is actually a simple repair.

Ensuring that your liquid nitrogen storage freezer is working correctly and optimally is our top priority, and our customers are often surprised at how simple tweaks can dramatically increase lab efficiency. Taking from decades of hands on experience servicing and repairing freezers, there is little we have not encountered.

Our web store contains mountains of technical data on our MVE biomedical products, including spec sheets, catalog sheets, user manuals, as well as technical tips MVE has posted over the decades. (insert link to knowledge and resource page on princetoncryo.com here?)

If you are looking to purchase this equipment outright, our web store shows published list pricing, however we typically offer competitive discounts when quotes are requested.

Preventative Maintenance and Service Calls

We offer preventative maintenance contracts for all MVE (and some other) products.

Why not catch issues before they become a problem? Our services start with systems checks and recommendations, all the way up to full maintenance plans with parts’ replacement.

Our maintenance can include temperature and LN2 level calibrations, freezer log download and comprehensive history review, regulr parts replacement, and controller software upgrades.

At times, older freezers need to be fully thawed to repair certain nagging issues, such as ice buildup, temperature probe replacement, or level reading issues. Our thaw procedures include a full thaw, moisture purge, cleaning, and then the full systems and parts check, before restarting the freezer.

Not every facility has a spare freezer to move your samples to, so we have several spare freezers in stock available for rent to facilitate this procedure.

Please feel free contact us for a consultation or a quote for your facility’s freezer maintenance, we tailor our service for each customer’s unique needs .

Installation Qualification, Operational Qualification, Performance Qualification (IQ/OQ/PQ)

Princeton CryoTech offers an in-depth IQ/OQ/PQ for all MVE Cryogenic Storage Freezers.

Our proprietary 10-page document is specific to your freezer and performed at installation. A qualified technician sets up the freezer for operational and performance qualification, setting up the freezer controller to log every 10 minutes, providing 1-2 weeks of validation reporting to be included with the final documentation.

A standard IQ/OQ/PQ is done on a new, empty freezer; however several options are available for more in depth analysis, including:

  • Advanced temperature mapping with Kaye Validator
  • Load testing with dummy samples and racks
  • Additional scenarios, including ‘LN2 supply removal’, or ‘open lid test’

Contact our experienced team to get a custom quote for your specific IQ/OQ/PQ and validation needs.

Liquid Phase Vs. Vapor Phase Freezers

Liquid Phase Vs. Vapor Phase Freezers - what to choose?

One of the first questions to ask yourself when choosing a cryogenic storage freezer is whether you plan to store in the liquid nitrogen itself, or in the vapor phase sitting above the cryogenic liquid. We are here to help you understand the pros and cons, so you can make an informed decision.


Liquid Phase Freezer Storage

Storing sample containers directly in liquid nitrogen is the earliest method of cryogenic storage, and arguably the most stable. The temperature of atmospheric pressure LN2 is -196 C (-320 F), with only slight variation at different elevations, so there is never any guessing as to the temperature inside a liquid phase freezer.

A huge benefit to liquid storage is the amount of liquid actually sitting inside a freezer versus a vapor phase freezer. While vapor phase freezers typically have 6 to 8 inches of liquid nitrogen, a liquid phase freezer will have 20-30 inches. At an rate of a 1/2" per day of usage, the liquid phase freezer is best suited for an emergency situation, as it will take much longer for the freezer to fully deplete.

Liquid phase freezers are also simpler to manufacture, and are therefore generally less expensive in per sample capital expenditure. MVE Series and MVE Stock Series are among the model classes that are commonly used for storing directly in liquid.

Reference Material:


Vapor Phase Freezer Storage

Vapor phase freezers got their start as a solution to cross contamination concerns. It has been found that certain viruses and pathogens can survive in liquid nitrogen, and there have been cases of cross contamination in samples sharing the same liquid nitrogen. Cross contamination is less of a concern in vapor, as these contaminants cannot transfer via nitrogen vapor.

MVE HE and HEco model freezers are specific to storing in nitrogen vapor, rather than in liquid nitrogen. Although nitrogen vapor is always warmer than it’s liquified state, newest generation freezers still keep even the warmest part of the freezer incredibly close to the temperature of liquid nitrogen, typically around -190 C.

MVE vapor phase freezers have achieved such success with vapor phase freezers due to their unique design and efficiency. First, much of the top is vacuum jacketed like the rest of the tank, as opposed to the full size foam lids of liquid phase freezers. This additional insulation makes the freezer highly efficient.

Secondly, the internal rotating carousel is instrumental to the design, and performs two functions. The carousel both allows easy access to all of the sample racks, and also maintains a very low temperature gradient throughout the freezer. The fully aluminum carousel is a great conductor of heat, which keeps the top of the freezer almost as cold as the bottom – A stark difference to the temperature gradient seen when people attempt to convert a liquid freezer to a vapor freezer.

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Warning: Converting Liquid Phase Freezer to Vapor Phase

Many use their liquid phase freezer as a vapor phase freezer, by only filling the bottom with LN2 and keeping the samples above that level. This can be done with either a vapor platform, or simply leaving bottom racks empty.

There is nothing wrong with doing this – as long as it is known that there is a much larger temperature gradient within the freezer, and the top rack can get as warm as 125 C, which is often warmer than most facility’s temperature threshold for cryogenic storage.

If you are looking to purchase a freezer, and want to save money by buying a liquid phase freezer, and using it as a vapor phase freezer – You may be actually spending more money than you think. In a vapor phase freezer, you use 100% of the published capacity. In a converted liquid phase freezer, you lose between 25% and 50% of the published capacity, between the space taken by liquid, and the space at the top not validated for temperature. When you do the math, it costs less per sample to store in a true vapor phase freezer.