Liquid or non-liquid?

Liquid and non-liquid cooling systems within the 80-500K temperature range

Oxford Cryosystems now offers both liquid and non-liquid cooling systems within the 80-500K temperature range. Choosing the best system for your lab is not always a simple process, and depends on a number of factors. The information on this page is designed to allow you to compare our liquid and non-liquid systems and decide which is right for you.

Comparison of Cryostream and Cobra

The Cryostream uses liquid nitrogen from Dewar vessels to produce a cold gas stream, which can be controlled within the range of 80-400 K for the 700 series Cryostream, or 80-500 K for the Cryostream Plus or Compact.

The Cobra uses mechanical refrigeration to cool down room-temperature dry nitrogen gas which can be controlled within the range of 80-400 K or 80 – 500 K for the Cobra Plus. The nitrogen gas is provided either by in-house piped gas if available, or by the optional nitrogen gas generator, which extracts nitrogen gas from the air.

The following table allows comparison of the Cobra and Cryostream for a range of parameters.

Cryostream Cobra
Low initial purchase cost of system X
Minimal service costs or user can perform servicing X
Ability to run for weeks/months without user attention (i.e. for Dewar refilling) X
Avoidance of liquid nitrogen safety issues X
Avoidance of cost of liquid nitrogen X
Standard temp range 80 – 400 K X X
Plus version temp range 80 – 500 K X X
Stability of 0.1 K X X
Remote control and monitoring via Cryopad software X X


The choice between a Cryostream and Cobra depends very much on local circumstances. If a lab simply wants to move away from liquid nitrogen for logistical or safety reasons, or liquid nitrogen costs are high locally, it is worth considering a Cobra. If dry nitrogen gas is already piped into the lab, the Cobra becomes a particularly attractive option!

If liquid nitrogen is relatively cheap and easy to obtain (or better still piped into the lab), the Cryostream is probably the best option. The Cryostream is also the best option for those who like to be able to maintain the system themselves without the need for routine servicing by an engineer.

To discuss the options further, please contact us .