At what temperature must water not be discharged under pressure directly into drainage systems?

Water must not be discharged under pressure directly into drainage systems at temperatures of 140° F or higher to prevent damage to the drainage system and ensure the safety of wastewater treatment personnel. The reason for this temperature limitation is that hot water can readily cause thermal expansion and elevate the risk of pipe failure or damage to fittings within the system.

Moreover, excessively hot water can also harm the biological processes that occur in wastewater treatment facilities. The bacteria that break down organic solids in the treatment process are sensitive to temperature changes, and if the incoming water is too hot, it can disrupt their functioning, leading to treatment inefficiencies or failures.

By keeping the temperature below this threshold, the integrity of the drainage system is maintained, and the health of the wastewater treatment processes is safeguarded. The selection of 140° F as the maximum discharge temperature aligns with best practices and standards established in plumbing codes to promote safety and functionality in plumbing installations.