Search·Watts
Use this page to see which whole-home systems use this cartridge, review any notes we have, and open buying links once the fit looks right for your housing.
Brand
Watts
This cartridge number is linked to the whole-house systems below in our reference. Confirm your model or housing appears here, then compare dimensions and rating with what you have installed.
W20FFPHD
Watts phosphate / scale inhibitor cartridge
Replace about every 6 months
Fits these models (2)
Notes & next steps
Search again if you need a different model or part number.
20 x 4.5 in. cartridge for compatible BB20 sumps; confirm media type vs your need.