How many duct openings are required for a bypass humidifier?

A bypass humidifier typically requires two duct openings for proper installation and function. The first opening is connected to the supply duct, where it draws warm air from the furnace. The second opening is connected to the return duct, allowing cooled air to pass back to the humidifier and become moistened before being reintroduced into the supply system. This dual opening setup facilitates the circulation of air through the humidifier, ensuring optimal humidity levels are achieved in the living space.

The requirement for two openings also aids in balancing the airflow, as it allows for consistent and efficient distribution of moisture throughout the home. This is critical to maintaining indoor air quality and comfort, particularly in dry winter months when humidification is most needed.