American Journal of Civil Engineering and Architecture
ISSN (Print): 2328-398X ISSN (Online): 2328-3998 Website: Editor-in-chief: Dr. Mohammad Arif Kamal
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American Journal of Civil Engineering and Architecture. 2021, 9(2), 42-51
DOI: 10.12691/ajcea-9-2-1
Open AccessReview Article

Variable Refrigerant Flow in Air Conditioning of Buildings: System Configuration and Energy Efficiency

Mohammad Arif Kamal1, and Sahil Ali Khan2

1Architecture Section, Aligarh Muslim University, Aligarh, India

2Department of Architecture, Jamia Millia Islamia, New Delhi, India

Pub. Date: April 29, 2021

Cite this paper:
Mohammad Arif Kamal and Sahil Ali Khan. Variable Refrigerant Flow in Air Conditioning of Buildings: System Configuration and Energy Efficiency. American Journal of Civil Engineering and Architecture. 2021; 9(2):42-51. doi: 10.12691/ajcea-9-2-1


Variable Refrigerant Flow (VRF), also known as Variable Refrigerant Volume (VRV) refers to the ability of an air-conditioning (AC) system to control the amount of refrigerant flowing to multiple evaporators (indoor unit). This study evaluates the VRF system to its core, and how the system is more beneficial in terms of built environment than the traditional air-conditioning system. This type of type of system consists of a number of air handling units (possibly up to 48) connected to a modular external condensing unit. The refrigerant flow in the VRF system is varied using either an inverter-controlled variable speed compressor or multiple compressors of varying capacity in response to changes in the cooling or heating requirement within the air-conditioned space. With the help of these advanced compressor like the twin rotary compressor the metering device can be closed to controls the flow of refrigerant between the indoor and outdoor unit which helps in avoiding the overheating or overcooling of the space. VRF system also helps in covering the duct losses which is impossible to cover in traditional system as VRF system is ductless or minimum duct are used in the process.

air conditioning buildings variable refrigerant flow energy efficiency compressor

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