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CTS has done pioneering work and has been building units and systems with CO2 deep-freezing since 2018. Since then, we have supplied around 400 units and systems with this technology. Due to the requirements of the new F-Gas Regulation, the next step is now being taken towards pure CO2 cooling.

What changes will the new F-Gas Regulation bring?

In October 2023, the trilogue on the ongoing amendment of the F-Gas Regulation was concluded with a compromise proposal to amend the Regulation. On January 16, 2024, the Council of the EU approved the draft. It was signed by the Council and the European Parliament and published in the Official Journal of the EU. The new EU Regulation 2024/573 has now been in force since March 11, 2024. The regulation includes a new equipment category of „self-contained refrigeration systems“ in the group of „stationary refrigeration“ with the following description: ‘self-contained’ means a complete factory-made system which is in a suitable frame or casing, is fabricated and transported complete or in two or more sections, can contain isolation valves and in which no gas-containing parts are connected on site.
Devices and systems for environmental simulation fall under this category, for which a GWP limit of <150 applies from 2025. No synthetic refrigerants with a GWP below 150 are available for use in the environmental simulation sector. This means that CO2 is the only available, non-flammable refrigerant that can be used.

The revision of the regulation sets further ambitious targets. The quota system for partially fluorinated hydrocarbons (HFC phase-out) will be tightened. The use of HFCs and HFOs - the most commonly used F-gases, which account for around 90% of F-gas emissions - is to be reduced by around 95% by 2030 compared to 2015 and reduced to zero by 2050. This reduction will primarily affect refrigerants with a very high GWP, such as R23, which will then only be available in small quantities at very high prices. This is particularly important for the maintenance of existing appliances, as the use of refrigerants with a high GWP for applications below -50°C will continue to be permitted without restriction.

Service and maintenance of existing systems is also newly regulated by the F-Gas Regulation (Article 13, Control of use). For the use of new refrigerants in refrigeration systems, a GWP limit of <2500 applies from January 1, 2025 and a limit of GWP <750 from January 1, 2032.
There are no restrictions on the use of recycled or reclaimed refrigerants for the service and maintenance of existing systems until 31.12.2029. From 2030, a GWP limit <2500 will apply for these

Refrigerants - whether new, recycled or reconditioned - are not subject to any restrictions for the service and maintenance of existing systems for cooling below -50°C and for military equipment due to exemptions.

This means that the operation, servicing and maintenance of all CTS units and systems supplied with one or two-stage refrigerant circuits (refrigerant R452A), cascades with a final temperature down to -70°C (refrigerant R23/R452A) and cascades with a CO2 deep-freeze stage (pre-cooling stage R452A or R449A) remain possible for an unlimited period of time.

A new addition is the requirement for an additional leakage test, which must be carried out at the earliest 24 hours after repair with initial leakage test, but at the latest after 30 days. For all appliances with a leakage test requirement, this means that an additional service call must be scheduled to carry out a further leakage test in the event of repairs after which a leakage test is required.

Are there exceptions for new appliances in the „STATIONARY REFRIGERATION“ group?

This question has not been clearly clarified. Equipment category 4 allows exceptions „if this is necessary to comply with the safety requirements on site“.

The following information can be found in the ordinance:

Article 3: Definitions:
‘safety requirements’ means requirements on the safety of using fluorinated greenhouse gases and natural refrigerants or products and equipment containing or relying on them, prohibiting the use of certain fluorinated greenhouse gases or their alternatives, including when contained in a product or in equipment at a specific place of intended utilisation due to site and application specificities that are set out in: (a) Union or national law; or (b) a non-legally binding act containing technical documentation or standards that have to be applied to ensure safety at the specific location, provided that they are in accordance with relevant Union or national law

Article 13: Control of use:
The putting into operation of any equipment or utilisation of any product listed in points 2(b), 4, 5(c), 7(b), (c) and (d), 8(b) to (e), 9(b) to (f), 11(c), 17(c) and 19(b) of Annex IV after the respective prohibition date specified in those points shall be prohibited unless the operator can provide evidence that: (a) the relevant safety requirements at the particular location do not permit the installation of equipment using fluorinated greenhouse gases below the global warming potential value specified in the respective prohibitions; or (b) the equipment was placed on the market before the relevant prohibition date set out in Annex IV.

The following article can be found in the Deutsche Handwerkszeitung from March 4, 2024: Safety requirements could, for example, prevent the use of flammable (e.g. propane) or toxic refrigerants (e.g. ammonia). For example, safety requirements from DIN EN 378 may mean that F-gases may continue to be used. How exactly this regulation will be implemented has not yet been finally clarified and is not explained in more detail in the regulation. The latest information on this is as follows: This decision and the corresponding documentation obligation lies with the operator of the system, who should obtain the necessary expertise from a specialist refrigeration and air conditioning company or expert if necessary. It is not necessary to apply to an authority or similar. However, if too many people choose this option in order to continue using fluorinated safety refrigerants (without actually having to), the quota will be used up too quickly.

For us, this currently means that possible exemptions could only become effective in individual cases and upon proof from the operator in the event of safety requirements at the installation site.
This does not result in a general exception „for safety reasons“, which makes implementation impractical in our view.

A further exception arises from appliance and system configurations in which „gas-containing parts are connected on site“. This applies, for example, if an external, air-cooled condenser and/or an external machine set is connected to the appliance/system at the installation site and additional refrigerant-carrying lines have to be installed, connected and filled on site. In this case, classification in equipment category 5 is possible, in which exceptions „for cooling products to below -50°C“ from the limit of GWP 2500 applicable there are still possible until the end of 2029. From 2030, the limit value of GWP <150 will also apply in appliance category 5.

What about exemptions for military equipment?

The following can be found in the ordinance:

Article 11: Restrictions on placing on the market and sale:
The placing on the market of products and equipment, including parts thereof, listed in Annex IV, with an exemption for military equipment, shall be prohibited from the date specified in that Annex, differentiating, where applicable, according to the type or global warming potential of the gas contained.

Military equipment is therefore exempt from the restrictions. However, if you look at the definitions under Article 3, you will find the following for military equipment:
‘military equipment’ means arms, munitions and material intended specifically for military purposes which are necessary for the protection of the essential interests of the security of Member States.

This definition makes no reference to test equipment for testing military equipment. Therefore, it is still completely open to us whether this exception also applies to environmental simulation tests on military equipment or components for military equipment.

Refrigeration implementation at CTS

CTS has been building chambers and systems with CO2 deep-freezing as standard since 2018; to date, hundreds of chambers with this refrigeration technology have been delivered and are operated by our customers. Due to the requirements of the new F-Gas Regulation, the next step is now being taken towards pure CO2 cooling.

CTS already offers chambers and systems exclusively with CO2 cooling. Depending on the final temperature, temperature change rate or heat compensation requirements, our customers can choose between single-stage, two-stage and cascade systems with CO2 pre-cooling and deep-freezing stages.
The cascade systems in particular offer almost full cooling capacity down to -40°C and therefore also enable tests with linear cooling down to -40°C.

The CTS CO2 solutions offer many advantages:

  • Ideal solution for automotive test applications down to -40 °C
  • Achievable final temperature of up to -48°C
  • Almost full cooling capacity down to -40 °C in cascade systems
  • Cooling with purely natural refrigerant CO2 (R744)
  • CO2 is non-toxic, non-flammable
  • CO2 is freely available worldwide in unlimited quantities and is very inexpensive
  • Proven and tested technology
  • No standstill cooling necessary
  • low filling quantities
  • no leak test required for CO2 coolant circuits

A quick overview of the requirements of the new F-Gas Regulation for new appliances and maintenance of existing appliances can be found at:

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