Although a conventional ducted system is the HVAC system used by most of the household in the United States, the ductless mini split system is gaining popularity in the market. The ductless mini split heat pump system consists of an outdoor unit that provides hot or cold refrigerant into a house to one or more wall- or ceiling-mounted indoor fan units. Ductless mini splits can have several advantages over conventional systems including improved thermal comfort, performance, and energy saving. There have been several studies and research in the field of ductless mini splits to learn about the advantages and disadvantages of the system and determine its market potential. Future research and progress in the field require an in-depth understanding of the current state and challenges of the research done about the system. Therefore, the purpose of this paper is to identify the research and studies performed using ductless heat pumps and to quantify them based on their research focus within the topic. So, by performing a comprehensive literature review of the current state of research in the field of ductless mini splits, we have presented an overview of the methodology used and the results obtained by several researchers. In this paper, a reference guide is created to classify the papers based on the topic. The literature is classified into four main topics: performance, thermal comfort, energy savings, and market potential, and then summarized based on the topic. Moreover, the reference guide is also used to distinguish simulations from field evaluations.


© 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).



Date of publication

Spring 5-4-2022



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