Pentair 2-3/8" Adapter Drain Adapter Fitting

The Pentair 2-3/8" Adapter Drain Adapter Fitting (part number 155017 or 155017Z) is a specialized external plumbing component engineered exclusively for the lower drainage port of Pentair Triton II side-mount sand filtration systems (including models TR40, TR50, TR60, TR100, and TR140). Injection-molded from a heavy-walled, high-impact ABS thermoplastic composite, this threaded adapter spans approximately 2-3/8 inches in diameter. Its primary functional role is to serve as the critical transition bridge between the filter tank's large bottom drain opening and the external drainage spigot or winterizing plug. When threaded tightly into the lower tank chassis with its matching gasket, it establishes an absolute watertight pressure boundary capable of safely containing continuous internal hydraulic operating pressures up to 50 PSI during standard filtration and intense backwash cycles. This fitting ensures pool service technicians can smoothly execute seasonal winterizing drawdowns or media flushes without stripping threads or causing slow water weeping at the base of the vessel. Built to endure constant contact with wet silica sand, intense ground moisture, and highly concentrated pool sanitizers like chlorine, bromine, and acid washes, its robust plastic architecture resists cracking and structural distortion over decades of heavy exposure. Due to its thick-walled, stubby cylindrical design and deep-cut threads, this individual drain adapter fitting carries a net product and shipping weight of approximately 0.18 to 0.25 pounds (about 2.8 to 4.0 ounces).