What is the minimum internal diameter for condensate waste and drain lines?

The minimum internal diameter for condensate waste and drain lines is critical for ensuring proper drainage and preventing issues related to clogs or insufficient flow. A diameter of 3/4 inch is generally accepted and specified in mechanical codes for these types of applications, as it provides adequate capacity to handle the volume of condensate produced by HVAC systems without risking backup or overflow.

Using a diameter smaller than 3/4 inch might lead to potential drainage problems, as it may not effectively accommodate the drainage needs, especially during peak operation times when the condensate levels are higher. This adherence to a minimum diameter also helps maintain proper venting and airflow within the drainage system, reducing the likelihood of siphoning and allowing for efficient gravity drainage.

Thus, a minimum of 3/4 inch ensures that the condensate system operates effectively and complies with the necessary code regulations.