Design and Test of a Small Ammonia Heat Pump
2011 (English)In: 10th IEA Heat Pump Conference 2011, 2011, s3_p18- p.Conference paper (Other academic)
Since synthetic refrigerants may cause environmental damages, by depleting the ozone layer or by contribution in global warming, many researchers, in recent years, have focused on the use of natural refrigerants such as ammonia to replace the synthetic ones. Although ammonia has been used in large refrigeration systems, its application in small units, say a small heat pump, is quite rare.
The work presented in this paper is design and test of a small water-to-water ammonia heat pump, providing about 7 kW heat, sufficient for space heating and tap water heating of a single-family house. To reduce the charge and to overcome the problem of accumulation of oil at the bottom of evaporator, a minichannel heat exchanger is used as evaporator. Oil miscible in ammonia is also used to facilitate the oil return to compressor. A permanent magnet motor together with an inverter is used to run the compressor. Supplying the 7 kW heat, the heat pump runs efficiently with heating capacity to compression work ratio of 5.1 at evaporation and condensation temperatures of -5 °C and 40 °C.
Place, publisher, year, edition, pages
2011. s3_p18- p.
ammonia, heat pump, refrigerant charge, minichannel heat exchanger, ground source
Research subject SRA - Energy
IdentifiersURN: urn:nbn:se:kth:diva-62588OAI: oai:DiVA.org:kth-62588DiVA: diva2:482630
10th IEA Heat Pump Conference 2011, Tokyo, June 27-August 31, 2011
QC 201204162012-01-242012-01-192016-06-22Bibliographically approved