Mock-up test on the application of phase change materials in underfloor radiant heating system in apartments

Apartment housing in South Korea mainly uses underfloor radiant heating systems. However, the performance of these systems has not improved significantly in recent years. The heat storage capacity of the floor influences the heating energy required and impacts the comfort level of occupants. Thermal energy storage materials, such as phase change materials (PCMs), can be employed to increase the heat storage capacity. This study aims to investigate the appropriate installation position and phase change temperature of PCMs applied to an underfloor radiant heating system. Two mock-up tests were conducted. First, the PCM was installed on the top, side, and bottom of the heating pipe, and the floor surface temperature was compared with that of a conventional floor structure in each case. Second, PCMs with phase change temperatures of 34 and 43 celcius were installed in different rooms, and the floor surface temperatures were compared. The results indicated that PCMs should ideally be installed at the bottom of the heating pipe, and a phase change temperature of 34 celcius is appropriate for use in Korean underfloor radiant heating systems.