Document IIF

Pompes à chaleur sol-air à détente directe.

Direct-expansion ground-coupled heat pumps.


In Austria, direct-expansion ground-coupled systems with horizontally installed ground coils are dominating the heat pump heating market. Reasons are lower costs and higher efficiencies compared with secondary loop systems due to omitting the circulation pump and one heat transfer loss; the Seasonal Performance Factor (SPF) of these systems is in the range of 4 to 5. In the case of limited ground area or existing houses, the alternatives are vertical systems, against direct-expansion systems. A new concept is a heat pipe as ground heat exchanger, and due to the fact that in this heat pipe only CO2 without oil is self circulating, no environmental concerns exist. The SPF achievable with such systems is similar to that of direct-evaporation systems.

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  • Titre original : Direct-expansion ground-coupled heat pumps.
  • Identifiant de la fiche : 2004-3018
  • Langues : Anglais
  • Source : 21st IIR International Congress of Refrigeration: Serving the Needs of Mankind.
  • Date d'édition : 17/08/2003


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