Test chambers from Weiss Technik without fluorinated gas from 2025

Conversion to refrigerant R744 (CO2)

The revised EU regulation on fluorinated greenhouse gases has been in force since 11 March 2024. The introduction of the “Self Contained Refrigeration Equipment” category means that almost all environmental simulation equipment must be converted to new refrigerants by January 2025 – instead of 2030 as originally planned. Exceptions apply only to “safety requirements”.

Only combustible gases or CO2 (R744) reach the new limit of 150 for the Global Warming Potential (GWP). Because temperature and climatic test chambers use a heating system in addition to a chiller, flammable refrigerants are not an option. Weiss Technik has already proven this with the introduction of the refrigerant R469A/WT69 in 2019 and has had its own mixtures of substances certified with the classification A1 (non-flammable, non-toxic). At the time, components for CO2 chillers were not available for common appliance sizes or were too expensive. This has changed in recent years.

The prevailing pressure in CO2 refrigerating units (i.e. 57 bar even at 20°C) requires high-pressure-resistant components up to 120 bar. These are now available in the quality required for environmental simulation systems and have been intensively tested by Weiss Technik. The test chambers, which run exclusively on CO2, are currently being delivered to beta testers.

CO2 with the identifier R744 is an extremely efficient refrigerant that offers many advantages down to its physical limit at −56°C. This includes the use of smaller components that are more energy-efficient. The noise level of the cabinets is also lower. And the acquisition costs are lower compared with expensive −70°C cascade systems. In addition, the fluorinated gas regulation does not apply to pure CO2 refrigerating units. This means that the leakage tests stipulated therein do not apply.

Weiss Technik will switch a large part of the −40°C range to CO2 with GWP 1 by the end of 2024. Over the course of the year, customers must prepare themselves for the discontinuation of many appliance models that currently use R449A as a refrigerant. Orders for systems that run with previous refrigerants can still be placed until autumn 2024 (depending on the delivery time). However, they must be delivered by the end of the year so that they can continue to be operated.


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