What is the minimum pitch of a condensate drain connected to a compensating furnace?

The minimum pitch of a condensate drain connected to a compensating furnace is critical for ensuring that condensate can flow properly and does not accumulate in the piping. A pitch of 1/8 inch per foot is typically specified as the minimum requirement for condensate drains. This slight slope helps gravity assist in the drainage of water, minimizing the risk of clogs or backups, which can lead to operational issues or damage to the furnace.

Choosing a drain pitch that is too shallow might not provide adequate drainage, increasing the chances of standing water within the system. Conversely, a steeper pitch can sometimes lead to increased velocity in the drain line, which may also cause issues such as noise or potential water hammer in specific conditions. Therefore, a minimum of 1/8 inch per foot is an established standard to ensure efficient drainage without introducing complications into the system.