Pentair Influent Manifold for THS3461

The Pentair Influent Manifold for THS3461 (part number IMTHS3461, or included as part of comprehensive plumbing valve kits like 155703) is a heavy-duty, commercial-grade internal distribution network engineered exclusively for the Pentair THS Series 34-inch horizontal high-performance sand filtration systems (model THS3461). Fabricated from thick-walled, industrial-grade PVC and CPVC thermoplastic polymers, this high-volume piping network installs directly along the top interior length of the fiberglass filter tank. Its primary operational role is to receive raw, high-velocity incoming pool water from the main 6-inch external flange line and channel it uniformly through a series of precision-spaced diffusers across the entire surface of the underlying silica sand bed. By transforming a single turbulent stream into a low-velocity, balanced hydraulic blanket, the manifold prevents high-pressure water from channeling, gouging, or displacing the sand media, which maximizes filtration area efficiency and ensures the system safely operates under continuous hydraulic loads up to 50 PSI. Engineered to survive years of permanent submersion in harsh commercial pool water, it completely resists structural warping, mechanical fatigue from powerful backwash flow reversals, and corrosive degradation from high-strength chlorine, bromine, and routine chemical shock treatments. Due to its rigid, expansive plumbing footprint and multi-port distribution branch architecture designed to handle commercial flow rates up to 270 GPM, this heavy-duty individual interior influent manifold assembly carries a net product and shipping weight of approximately 11.50 to 14.00 pounds (though complete exterior valve manifold installation kits matching this model can weigh up to 300 pounds).