ChaDol: A Chilled-Water Ondol Prototype for Radiant Floor Cooling
Erica Kim
Seoul International School, Seoul, Korea
Publication date: November 20, 2025
Seoul International School, Seoul, Korea
Publication date: November 20, 2025
DOI: http://doi.org/10.34614/JIYRC2025II50
ABSTRACT
Higher temperatures and increased air conditioning usage further highlight the need for sustainable cooling. This paper describes ChaDol, a chilled-water ondol prototype inspired by Korea’s heritage radiant floor heating system adapted for radiant cooling. The prototype consisted of multi-layered insulation, a serpentine pattern of PVC tubing for chilled-water circulation, and aluminum tape for enhanced lateral heat spreading. Thermal characteristics were examined by Forward-Looking Infrared (FLIR) imaging at multiple instances over six days. By pumping water at ~20 °C, the surface temperatures reduced reliably by 6–7 °C by the end of one hour, and steady-state cooling was attained thereafter. Thermal spreading was additionally enhanced by aluminum tape through a further reduction of surface temperatures by ~9–10% relative to untreated areas. The system attained leak-free and stable working through minimal condensation. The findings confirm the promise of ondol-based radiant cooling and indicate that ChaDol offers an energy-efficient and water-sparing substitute for traditional air conditioning.
Higher temperatures and increased air conditioning usage further highlight the need for sustainable cooling. This paper describes ChaDol, a chilled-water ondol prototype inspired by Korea’s heritage radiant floor heating system adapted for radiant cooling. The prototype consisted of multi-layered insulation, a serpentine pattern of PVC tubing for chilled-water circulation, and aluminum tape for enhanced lateral heat spreading. Thermal characteristics were examined by Forward-Looking Infrared (FLIR) imaging at multiple instances over six days. By pumping water at ~20 °C, the surface temperatures reduced reliably by 6–7 °C by the end of one hour, and steady-state cooling was attained thereafter. Thermal spreading was additionally enhanced by aluminum tape through a further reduction of surface temperatures by ~9–10% relative to untreated areas. The system attained leak-free and stable working through minimal condensation. The findings confirm the promise of ondol-based radiant cooling and indicate that ChaDol offers an energy-efficient and water-sparing substitute for traditional air conditioning.
