A Study for Evaluating Performance of a Radiant Floor Cooling

Abstract

This study aims at developing a radiant floor cooling system using existing Ondol (radiant floor heating system) system in Korea. Though the radiant floor cooling system could provide thermal comfort with higher energy efficiency, some problems still exist such as condensation on floor surface while the radiant floor cooling system is in operation. To solve this problem, in this study the radiant floor cooling integrated with controlled ventilation was proposed as an alternative approach. The ventilator brings the fresh outside air to meet the minimum requirement for indoor air quality and it has a capability of dehumidifying the ventilation air by circulating the chilled water through cooling coil in the ventilator. Humidity control is an essential requirement of the control system. A dewpoint sensor will stop chilled water flow to the floor and activate dehumidification by means of a cooling coil in the ventilator. The radiant floor system also has thermal storage effect which is demerit in which response of the system to load changes is slow compared to that of an air-conditioning system. In order to improve this demerit, primarily the outdoor temperature was compensated in determining the supply water temperature and then the indoor temperature was fed back to the controller, so call the outdoor reset with indoor temperature feed-back was applied for the control of a radiant floor cooling. To evaluate the performance of proposed system, both the physical experiment in a laboratory setting and computer simulation have been conducted for the assessment of thermal environmental conditions and energy efficiency