Pentair 1/4" x 3/8" Vent Tube

The Pentair Tan Spring Check Valve Service Kit (part number 27001-0130S or 27001-0130SZ) is a crucial internal backflow-prevention component engineered exclusively for the internal plumbing assemblies of select above-ground and inground pool or spa filtration networks. This genuine original equipment manufacturer (OEM) replacement component is standard hardware designed specifically for the tan-colored vessel bodies of the Pentair Sta-Rite System 2 family, seamlessly integrating with the full line of System 2 Modular Media cartridge filters (PLM100, PLM125, PLM150, PLM175, PLM200, and PLM300) as well as System 2 Modular Diatomaceous Earth (D.E.) filters (PLD50, PLD70, PLDE36, and PLDE48).

Injection-molded from a heavy-walled, high-impact, and chemically inert polymer compound, this compact mechanical plumbing fixture measures approximately 3 inches in length by 2.5 inches in width. Its primary operational role is to establish an automatic, one-way hydraulic gateway inside the filter tank assembly. The valve features a durable, built-in internal tension spring that holds a sealed poppet or flapper assembly closed by default. When the pool circulation pump is actively running, the incoming water pressure overrides the spring tension, pushing the valve open to let turbulent water enter the purification core. However, the moment the pump shuts down or loses prime, the spring-loaded mechanism instantly snaps shut against its matching rubber gasket. This immediate physical barrier prevents water and un-bonded filter media—such as loose D.E. powder or collected debris—from flowing backward into the pump housing, suction lines, or pool return inlets, which is especially vital on equipment pads positioned below the pool’s surface level or connected to dedicated spa overflows.

Capable of operating continuously within high-velocity circulation streams and sustaining operating metrics up to 50 PSI, its rugged polymer housing and stainless steel spring completely resist structural warping, spring fatigue, and advanced chemical degradation from prolonged contact with pool sanitizers like chlorine, bromine, and winterizing acid flushes. Due to its thick-gauge plastic configuration and dense internal metal tension spring hardware, this individual replacement spring check valve carries a net product and shipping weight of approximately 0.50 to 1.00 pound (about 8.0 to 16.0 ounces).