What is the minimum size and slope requirement for a condensate drain?

The minimum size and slope for a condensate drain is critical in ensuring proper drainage and preventing water accumulation or backflow, which can lead to operational issues or water damage. A 3/4 inch drain with a slope of 1/8 inch per foot is recognized as a standard requirement in many plumbing and mechanical codes.

Using a 3/4 inch diameter ensures that the drain can handle the volume of condensate typically produced by cooling systems without clogging. The specified slope of 1/8 inch per foot allows for adequate drainage by using gravity to effectively move the water away from the source, thereby preventing any potential pooling of water in the drain line. This slope is gentle enough to avoid creating air pockets or resistance in the line while still promoting effective drainage.

Other options provide either insufficient diameter or slope that could compromise the flow of the condensate. For instance, a smaller diameter may lead to clogs and reduced flow capacity, while a steeper slope can lead to increased friction and potential damages to the drainage system. The criteria established in option B balances efficiency with functionality, making it the appropriate choice for condensate drainage systems.