Due to their benefits in interior thermal comfort, energy saving, and noise reduction, radiant cooling systems have received wide attention. Radiant cooling systems can be viewed as a part of buildings’ maintenance structure and a component of cooling systems, depending on their construction. This article reviews studies on heat exchange in rooms utilizing radiant cooling systems, including research on conduction in radiant system structures, system cooling loads, cooling capacity, heat transfer coefficients of cooling surfaces, buildings’ thermal performance, and radiant system control strategy, with the goal of maximizing the benefits of energy conservation. Few studies have examined how radiant cooling systems interact with the indoor environment; instead, earlier research has focused on the thermal performance of radiant cooling systems themselves. Although several investigations have noted variations between the operating dynamics of radiant systems and conventional air conditioning systems, the cause has not yet been identified and quantified. According to heat transfer theory, the authors suggest that additional research on the performance of radiant systems should consider the thermal properties of inactive surfaces and that buildings’ thermal inertia should be used to coordinate radiant system operation.

In most regions of southern China, condensation frequently occurs on building surfaces during the period from March to April. This phenomenon has been affecting people’s safety and structural properties. This article proposes an innovative anti-condensation floor system based on the reverse Carnot cycle. The evaporation side treats the air and reduces the moisture content, and the heat extracted from the condensation side is recovered by a heat exchanger and transferred to the floor through capillary mats. Simulation studies of the dynamic operation performance have been conducted through the TRNSYS 18 software. The results show that an innovative anti-condensation floor system can effectively keep the floor dry in Guilin. At the same time, regarding the indoor comfort level index, the PMV value is within ±0.5, and the energy consumption of the system is 42% less than that of the cooling dehumidification system. The system also performs well in representative cities where the air moisture content is less than 12 g/kg. This article also provides a reference for the feasibility of radiant floor systems in humid climate areas.

Hygrothermal coupling changes wall heat transfer and moisture storage, but their implications for room dehumidification under intermittent air conditioning remain unclear. Chinese fir and brick building models, each comprising a ground-floor hall and an upper-floor bedroom, were developed for Guilin, China, with hot, humid summers and cold, humid winters. Measured Chinese fir properties were used, and indoor temperature and relative humidity predictions were validated against measurements in a Chinese fir dwelling. Heat-only (H), coupled heat and moisture transfer without wind-driven rain (HM), and coupled transfer with rain (HMW) were compared using continuously controlled wall loads and theoretical room demands under intermittent control. Relative to each construction’s H baseline, HMW reduced summer sensible wall cooling loads, while room sensible cooling demand changed in either direction. Summer dehumidification demand increased by 12.72%–17.42% for Chinese fir and 23.61%–46.49% for brick; winter hall heating demand increased in both. During 1–30 July, adding rain to HM increased mean east-wall water content by 23.00%–59.95%, while cumulative room dehumidification demand changed by less than 0.2%. Interior surfaces absorbed moisture during off periods and released it after nighttime startup, with release and dehumidification peaks occurring within the same or adjacent hours. Under the investigated conditions, wall sensible loads and moisture storage could not independently indicate room energy-demand changes. Joint assessment of sensible and latent demands requires interior-surface moisture exchange and operating schedules to interpret their relationship.