Control strategy and experimental analysis of a direct-expansion solar-assisted heat pump water heater with R134a

• Published in: Energy (Oxford) Vol. 145; pp. 17 - 24
• Main Authors: Kong, Xiangqiang, Jiang, Kailin, Dong, Shandong, Li, Ying, Li, Jianbo
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 15.02.2018; Elsevier BV
• Subjects: airtight storage; Alternative energy sources; Aluminum; Ambient temperature; China; Condenser tubes; Degree of superheat; Direct-expansion; Energy consumption; Gas expanders; Greenhouse gases; Heat exchangers; Heat pumps; Opening control method of EEV; prototypes; Solar collectors; solar energy; Solar radiation; Solar-assisted heat pump; surface area; Thermal performance; China; Solar-assisted heat pump; Degree of superheat; Direct-expansion; Opening control method of EEV; Thermal performance

A direct-expansion solar-assisted heat pump (DX-SAHP) system was designed and built in Qingdao China, which was used to supply domestic hot water. The system mainly consisted of a bare solar collector/evaporator with area of 1.56 m2, a rotary-type hermetic compressor with rated power of 400 W, an el...