What is the required distance between the upper edge of a cleanout and the lower edge of the lowest inlet to a masonry chimney?

The required distance between the upper edge of a cleanout and the lower edge of the lowest inlet to a masonry chimney is specified to be 6 inches. This dimension is important for ensuring proper functioning and maintenance of the chimney system. By maintaining this distance, it helps to prevent any restriction in airflow or buildup of debris that could obstruct the passage of combustion gases. Additionally, this clearance allows for adequate access for cleaning and inspection purposes, which is critical for the safe operation of any system utilizing a masonry chimney.

Choosing a distance that is less than 6 inches could lead to complications such as potential blockages or difficulties during routine maintenance. Thus, the 6-inch requirement strikes a balance between functional operation and ease of access for technicians.