What is the required downward slope for above-ground duct piping to the suction point?

The required downward slope for above-ground duct piping to the suction point is 1/8 inch per foot. This gradual slope is critical in ensuring effective drainage of any condensation or moisture that may accumulate in the ducting. By maintaining this specific incline, the system helps prevent water from pooling in the ducts, which can lead to reduced efficiency, increased wear on the system, and potential water damage.

A slope of 1/8 inch per foot balances the need for effective drainage while minimizing any potential impacts on airflow or system performance. Ensuring that the ducting adheres to this slope is an important part of proper installation and maintenance practices, as it supports system longevity and reliability.