IIR document

A high temperature heat pump using water vapor as working fluid.

Number: pap. ID55

Author(s) : LARMINAT P. de, ARNOU D., LE SAUSSE P., et al.


High temperature heat pumps are available for temperatures up to about 100°C, using ammonia or synthetic fluids. Beyond 100°C, very few products are available on the market. Previous theoretical studies have shown that water vapor is a very attractive fluid beyond 100°C. But the implementation was so far stumbling on complex technological issues. These difficulties have been tackled. A prototype was built and tested. It uses a two-stage centrifugal compressor directly driven by a high speed motor on magnetic bearings. It is designed for 700 kW heating capacity at 90°C evaporation and 130°C condensation. It was successfully tested for several months, with excellent reliability and performance, with a COP of 5.5 at design conditions. The compressor can be included in a closed circuit with heat exchangers, or used for direct vapor re-compression. A future commercial range could cover heating capacities in the range 500 to 3500 kW. The technology and results are presented in this paper, together with the perspectives of a future product range.

Available documents

Format PDF

Pages: 8 p.


  • Public price

    20 €

  • Member price*


* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).


  • Original title: A high temperature heat pump using water vapor as working fluid.
  • Record ID : 30012356
  • Languages: English
  • Source: 11th IIR Gustav Lorentzen Conference on Natural Refrigerants (GL2014). Proceedings. Hangzhou, China, August 31-September 2, 2014.
  • Publication date: 2014/08/02


See other articles from the proceedings (119)
See the conference proceedings