Hydrocarbons (e.g. propane, isobutane)
Versatile and tried and tested millions of times over
Hydrocarbons consist only of carbon and hydrogen. Common representatives of this group are the refrigerants propane (R290) and isobutane (R600a). Both have an ODP of zero and a GWP of three, are inexpensive and easy to obtain. Despite their flammability, they are easy to handle. They have already proven themselves in factory-filled systems. Worldwide, for example, hundreds of millions of household refrigerators work with isobutane as a refrigerant.
Hydrocarbons (HCs for short) also work in commercial refrigeration, for example in refrigerated counters and ice machines, or in air dehumidifiers and heat pumps.
HCs are also suitable for other applications, such as heating and cooling, but also for air-conditioning systems where carbon dioxide reaches its limits due to the high outside temperatures. Since the thermodynamic properties of HC refrigerants are very similar to those of synthetic refrigerants, refrigeration systems can be designed in the usual way. However, higher safety requirements must be observed, as HCs are flammable. But handling HCs is no secret - otherwise the use of camping stoves or gas grills would certainly not be permitted.
Consider your design
Despite the similarity in system design, refrigeration systems with hydrocarbons as refrigerants require, for example, different compressors and safety precautions than those with synthetic refrigerants. It is therefore not possible to replace, for example, R134a with hydrocarbons in an existing system. In addition to safety aspects resulting from the flammability of HCs, the oil used in the compressor plays an important role. Larger plants also require systems for leak detection and fire protection. Filling and refilling of the refrigerant hydrocarbon may only be carried out by specially trained personnel.
The additional costs of the system arising from the required safety technology are usually offset by the lower refrigerant costs. In view of the fact that synthetic refrigerants are continuing to rise in price (e.g. for refills), HCs offer a clear advantage in terms of economic efficiency.
