IIR document

Successful conversion of ECU air conditioner to R744.

Author(s) : HRNJAK P., MANZIONE J., ADAMS D., et al.


An existing environmental control unit (ECU) utilizing R134a, with a nominal capacity of 17 kW, was converted to operate with carbon dioxide in transcritical mode by Creative Thermal Solutions, a research company in Urbana, Illinois. Only the heat rejection coil and the compressor were replaced with components of a new design. In addition, an IHX and accumulator were installed as new components. The location of the air filter was modified but the same material was used. The new system showed higher efficiency and capacity even at very high ambient temperatures. This paper describes the systems, construction, and results.

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Pages: 2008-2


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  • Original title: Successful conversion of ECU air conditioner to R744.
  • Record ID : 2009-0324
  • Languages: English
  • Source: 8th IIR-Gustav Lorentzen Conference on Natural Working Fluids (GL2008)
  • Publication date: 2008/09/07


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