WATER R718 (H2O)

In some aspects water is good refrigerant because it has big latent heat, high critical temperature, it is not toxic, not flammable and it is harmless for the environment. The negative side is a very big water vapor specific volume in normal working condition, as well as very low working pressures (vacuum). Today, there is very low number of refrigerating systems with water as refrigerant in vapor compressor cycles with centrifugal and high speed axial compressors, as a part of air conditioning systems.

In order to increase energy efficiency, the development is focused on improving the compressors, especially axial with high revolution. The appliance of these refrigerating systems is unpredictible in near perspective, but it could be promising with special equipment.