Open AccessComparison of Two Reverse-cycle Defrosting Methods for a R290 Split Room Air Conditioner
Author(s) -
Yong Du,
Jiang Wu,
C. Wang,
Bo Lei
Publication year - 2021
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1180/1/012048
Subject(s) - defrosting , sump (aquarium) , refrigerant , environmental science , gas compressor , suction , air conditioning , process (computing) , reliability (semiconductor) , heat exchanger , process engineering , automotive engineering , materials science , waste management , computer science , thermodynamics , engineering , mechanical engineering , power (physics) , physics , operating system
R290 has obvious advantages in aspects of environmental protection and thermal properties, and researches on R290 room air conditioners (RACs) are attracting more and more attention. As for R290 RAC, the suction temperature is continuously low and a large number of refrigerants are dissolved in the compressor oil sump during defrosting process, resulting in a longer time length of the start-up process after defrosting. Two reverse-cycle defrosting methods, the discharge-throttling method (DTM) and suction-discharge bypass method (SDBM) are proposed in order to solve these problems. This paper compares the two defrosting methods on an R290 RAC by experiment and the results show that the defrosting time of DTM is relatively short, but the temperature at the inlet and outlet of the indoor heat exchanger is relatively low after defrosting. The SDBM can alleviate the situation of low suction temperature in the defrosting process, but the viscosity of the oil sump is large in the early stage of defrosting and the time length of the start-up process after defrosting is longer. Both methods have their own advantages and disadvantages, and the paper will provide an experimental basis for the reliability study of R290 RACs.