Pipe fitting

A fluid discharge system, comprising:

• a fluid heating appliance including a fluid reservoir;
• a valve adapted to be connected to an outlet of the appliance for selectively discharging fluid in response to temperature or pressure conditions upstream of the valve;
• a discharge conduit having an upstream end and a downstream outlet end;
• and
• a tubular fitting defining an elongate interior chamber having an inlet at an upstream end and an outlet at a downstream end, the upstream end of the fitting secured to a downstream end of the valve and the downstream end of the fitting secured to an upstream end of the conduit for providing a flow path through the chamber substantially coextensive and coaxial with the conduit, the wall of the fitting defining a plurality of radial passages opening into the interior chamber in fluid communication with the flow path and extending through the wall at an acute angle relative to the longitudinal axis of the fitting upstream of the flow path and opening to the atmosphere such that the openings into the flow path are downstream from the openings to the atmosphere,
• wherein fluid discharged from the valve passes through the chamber from the inlet to the outlet along the flow path without escaping through the passages, and wherein any backflow of the fluid is directed radially outwardly and angularly upstream through the passages to the atmosphere when the discharge line is blocked from fluid flow downstream of the fitting.