Smart indoor humidity and condensation control in the spring in hot-humid areas

Continuous wet weather occurring in the spring in hot-humid areas causes many inconveniences and discomfort for building occupants. Techniques that control indoor environments well under continuous wet weather are still lacking. A smart, indoor humidity and condensation control logic was proposed based on condensation prevention logic and the adaptations of local people in hot-humid areas. The smart control system was established, and the field test was conducted in an office building in Guangzhou, China, during typical continuous wet weather in 2017. The test confirmed that the expected targets were successfully achieved by the control system with a fault rate of 5%. Compared to the conventional control (dehumidifiers always running and windows freely opened), under the smart control, the indoor air temperature and MRT increased by 0.6-2.1 °C and 0.4-2.1 °C, respectively; the indoor relative humidity and CO2 concentration were similar; the occupants perceived the indoor environment as slightly cooler and wetter and as acceptable in terms of the thermal environment, humidity and air quality; and the daily mean energy consumption on regulating the environment decreased by 90%. The smart control shows great advantages for energy savings by proposing the control logic based on the adaptations of local people, integrating operable windows with dehumidifiers, and fully utilizing natural heat sources.