Abstract: After 48 hours of continuous operation in a high-temperature and high-humidity environment, the air conditioner indoor unit generates a significant amount of condensation water inside the human sensing module, posing risks such as circuit board short circuits and even fire hazards. To address this issue, a moisture condition analysis was conducted for the indoor unit, and a moisture-proof method for the human sensing module was proposed. Firstly, fluid simulation analysis of the air duct structure was performed to determine the causes of condensation water and the locations prone to its formation. Subsequently, a moisture-proof method for the human sensing module was proposed, involving the optimization of the lens structure, the application of UV adhesive to improve sealing, and the addition of insulation cotton to reduce thermal conduction. Finally, validation was carried out through moisture condition testing. Results show that the proposed moisture-proof method effectively resolves the issue of condensation water formation inside the human sensing module.

Key words: Occupancy sensor box, Condensation, Insulation, Structural optimization