Pentair Fitting Injection with Check Valve | IntelliPH® Controller | 521510 FS2004 Length 19 1/8" Outer Diameter

Length 19 1/8" Outer Diameter 7" Top Inner Diameter 3" Bottom Inner Diameter 3" Material 4 oz

Even if the gasket appears intact

O-rings on heater manifolds are subjected to repeated thermal cycling that degrades the seal over time

Operates smoothly at wide salinity ranges of 2000-6000 ppm

Pentair Fitting Injection with Check Valve | IntelliPH® Controller | 521510 FS2004 Length 19 1/8" Outer DiameterThe Pentair Fitting Injection with Check Valve (521510) is the OEM replacement injection fitting assembly for the Pentair IntelliPH pH controller system. This fitting serves as the chemical injection point where the IntelliPH controller delivers pH adjusting solution directly into the pool's return line. The integrated check valve prevents backflow of pool water into the chemical feed line, protecting the controller's dosing mechanism and maintaining