What is the discharge size for a sewage grinder outlet?

• A. 2 inches
• B. 1-1/4 inches
• C. 3 inches
• D. 1 inch

Answer: (B)

The key idea is the size of the outlet that the grinder pump pushes wastewater through. For a sewage grinder, the discharge port is standardized to work with typical residential piping, and the common size is 1-1/4 inches. This size provides a practical balance: it’s large enough to carry the pump’s flow without excessive friction, yet small enough to fit standard piping and fittings used in home drain systems. Larger outlets like 2 inches or 3 inches aren’t typical for residential grinder outlets, and choosing too small a size (like 1 inch) could restrict flow and lead to issues. So the discharge size is 1-1/4 inches.