In which orientation should fans ideally be installed in runs of vent pipe?

Fans should ideally be installed in a vertical orientation in runs of vent pipe to ensure proper airflow and optimal performance. This vertical position allows for efficient movement of air and helps prevent the accumulation of moisture and debris within the venting system.

When fans are installed vertically, they utilize gravity to assist in the movement of air, which can enhance their efficacy in drawing radon gas from the building and exhausting it outside. This installation orientation is particularly important in radon mitigation systems, where the objective is to maintain a constant and effective flow of air to mitigate radon levels inside a structure.

In contrast, horizontal or diagonal orientations can complicate airflow and potentially lead to issues such as reduced efficiency or increased likelihood of blockages due to gravity effects on any accumulated moisture or material. Thus, vertical installation is the preferred method for maximizing the efficiency and effectiveness of radon mitigation systems.