Can a refrigerant be replaced? - Implementation and best practice
- The topic of refrigerants may not be widely discussed in the public, but the effects of harmful refrigerants have been deeply focussed in the media over the past few decades. Today, it has been proven that there is a large hole in the ozone layer above Antarctica and that the general warming of the earth can also be detected at our latitudes. The snow line is rising, the weather is changing. Just this winter we have little to no snow.
International agreements require a reduction of harmful gases in the atmosphere. The states and also the manufacturers are forced to take measures. For example, the Swiss Confederation obliges the participation of manufacturers, distributors and operators of systems using refrigerants. These are electrical appliances such as refrigerators up to comprehensive systems such as climatic test chambers, as Clitec distributes them, to air-conditioned warehouses for large distributors.
In general, harmful refrigerants should be replaced by less harmful or harmless ones. In the segment of refrigeration, because we are in a market where equipment cannot be replaced quickly, the federal government has issued a transitional rule granting exemptions. The state of the technology decides. Exemptions are granted in the absence of a substitute, when a refrigerant is chosen that is stable and has a low impact on the climate, or when refrigerant leakage is minimized, in practice with regular testing for leaks of the refrigeration equipment. Furthermore, for systems with more than 3 kg of harmful refrigerants there is an obligation to register and a maintenance log book must be kept. For very specific system combinations, the approval from cantonal or national organizations is required. As a supplier of refrigeration- and heating systems, Clitec is familiar with the subject and is happy to provide advice.
Detailed view into the Refrigerants
In cooperation with the professional associations, the federal government has summarized an overview of the most important refrigerants. In the link is the current table from 2020. In the red zone are the ozone-depleting refrigerants such as R-502 with CFCs. These may no longer be placed on the market. In the orange range are refrigerants stable in air such as R-23 with HFC or the common R404A as a mixture. These are permitted on a limited basis. Refilling is still permitted today, but will no longer be permitted from 2030 on. In the green zone are the refrigerants that are not ozone depleting but are not stable in air. Only the obligation to register and the maintenance log book applies for systems with more than 3 kg of refrigerant per system. It sounds strange, but R-718 water belongs to this group. Gases such as R-290 propane and R-717 ammonia can be explosive if they escape, or R-717 ammonia or R-744 carbon dioxide can be harmful to health in large quantities. Therefore, measures for the safe operation must also be taken for such plants. And the last zone, non-harmful and stable in air refrigerants, is not listed. This zone does not concern the climate thematics. Here only measures for the safe operation are needed.
What does this mean in concrete terms in terms of implementation?
The implementation is not just easy. Many systems are designed for a specific refrigerant. Therefore, there is only a best practice applicable. The following points describe suggestions. What exactly is feasible is decided by the engineering of the operating company together with the refrigeration engineer.
- For the definition of harmfulness, the experts consult the GWP, Global Warming Potential, which states which greenhouse potential is expected. “Very bad” refrigerants can have up to a GWP of 15,000. R-502 has a value of 4657. That’s still pretty high. Alternatives include R-404A, which is stable in air and has a value of 3922, but is only slightly better than R-502 in terms of global warming potential. Mostly mixtures like R-513A with a GWP of 630 are used. The optimum in terms of GWP would be R-290 propane with a GWP of only 6.
- Each refrigerant has its own characteristics. Condensation and evaporation depend on pressure and temperature. Therefore, a specific refrigerant cannot simply be replaced by another. Refrigerators often use R-290 propane, frozen storage facilities use R-717 ammonia, or cryogenic systems use liquid nitrogen.
Furthermore, the condensers and evaporators must be precisely designed for the gases used and their specific properties, such as density and phase transitions. For certain refrigerants like the R-23, there is no suitable substitute except very expensive solutions from some manufacturers. Most common, therefore, the entire refrigeration equipment is replaced. The benefit, in addition to simpler operation, is massive energy savings through modern technology.
- Each refrigerant has different properties in terms of heat transfer. If you switch to a “lower” GWP, you may not be able to transport the same amount of heat. Specifically, this means that refrigeration systems can no longer cool as deeply or as well as they were designed to with the original refrigerant. Therefore, some manufacturers are also involved in the research-intensive development of equivalent refrigerants.
- And last but not least, operators of exempt facilities are on the short end of the stick. These are, for example, research facilities where the refrigeration equipment nor the refrigerant can be replaced. As the production of “harmful” refrigerants becomes increasingly difficult, supply bottlenecks arise. Many operators therefore build up a stock and buy large quantities. The market takes advantage of this and increases prices, in some cases exorbitantly. Thus, the operator of such plants incurs high operating costs.
Clitec can advise you on refrigeration- and heating technology as well as modernization
In our equipment, being it climatic test cabinets or climatic test chambers, we use refrigeration technology. Years of experience and active tracking of trends in refrigerants have made Clitec to a specialist in this field. Our customers include research institutions in environmental simulation, as well as companies in industry, biotechnology, pharmaceuticals and chemistry. Where high energies are put into or taken out from a system, we use temperature control technology. Thus Clitec offers besides plants for
plant- and insect breeding to stability tests and for material testing also high-performance refrigeration- and heating technology – equipment with high-quality technology, being it chillers or thermostats – provides safety. Clitec advises you in detail about the products and refrigerants.
Modernizations – also here Clitec can bring in the excellence of its experience. We have already carried out modernizations at large research institutes. Being it refrigeration- or heating technology replaced, refrigerants changed or even electrical control cabinets modernized to the latest state of the art. In a personal consultation on site, we can assess the condition of the systems as experts and then discuss the options and how to proceed. Clitec may take over the maintenance of the plants after modernization at the request of the operators and carries it out reliably. So that your equipment stays in good shape on the long term.