Performance characteristics of a two-stage CO2 heat pump water heater adopting a sub-cooler vapor injection cycle at various operating conditions

Changhyun Baek, Jaehyeok Heo, Jongho Jung, Honghyun Cho and Yongchan Kim

Energy, 2014, vol. 77, issue C, 570-578

Abstract: The objective of this study is to investigate the performance characteristics of an injection CO2 (carbon dioxide) HPWH (heat pump water heater) at various operating conditions. In the standard and standby heat loss test conditions, the performance of a two-stage CO2 HPWH adopting a SCVI (sub-cooler vapor injection HPWH) cycle was measured and analyzed by varying the compressor frequency, the water flow rate, and the injection ratio at various outdoor temperatures. In the standard tests at the outdoor temperature of −15 °C, the COP (coefficient of performance) of the optimized SCVI HPWH was 7.6% higher than that of the non-injection HPWH. During the standby loss tests at the water flow rate of 200 kg h−1, the COP of the optimized SCVI HPWH was 7.1% higher than that of the non-injection HPWH.

Keywords: CO2 heat pump water heater; Hot water temperature; Injection ratio; Vapor injection; Water heating performance (search for similar items in EconPapers)
Date: 2014
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (11)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544214010949
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:77:y:2014:i:c:p:570-578

DOI: 10.1016/j.energy.2014.09.038

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().