Review of Temperature and Humidity Control Technology for Heat Pump and Air Conditioning Systems

Nowadays, indoor temperature and humidity controls have been more important to provide thermal comfort to occupants. In residential and commercial buildings, split-type air conditioning systems have been widely used for its compactness and installation flexibility. However, the current split-type systems could not effectively control the thermal comfort of the occupants due to its insufficiency in humidity control. In this paper, the existing independent temperature and humidity controllers of the single unit split-type system are reviewed. Then, the study has extended to the variable refrigerant flow (VRF) system, which is a typical multiple-unit split-type system. Several VRF systems that has the humidity control option have been reviewed and their performance is discussed. Based on the literature review, the feasibility of VRF systems with independent temperature and humidity controllers is discussed