The drain pump is installed beneath the humidifier cylinder to discharge concentrated water generated during the humidification process. It is specifically designed to forcibly remove sediments from the humidifier cylinder, preventing buildup and ensuring stable operation. This forced drainage system overcomes the limitations of traditional drainage valves, maintaining a consistent drainage volume regardless of the water level in the humidification cylinder or the internal pressure of the air conditioning unit. This allows for precise control while effectively minimizing sludge generation. Additionally, the service piping configuration allows for inspection of the humidification cylinder and drainage system without requiring a power supply, enhancing convenience and ease of maintenance.