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AP431 3M Aqua-Pure Inline Filter Replacement Cartridge

Price $41.99 List Price Price $59.99 Save 30%
Availability: In Stock - Free Shipping
3M™ Aqua-Pure™ Whole House Scale Inhibition Replacement Water Treatment Cartridge AP431, AP43111, Scale, 10/Case
  • DESIGNED FOR USE WITH 3M Aqua-Pure Whole House Scale Inhibition Inline Water System AP430SS
  • Polyphosphates, included in this product, help to inhibit scale buildup in hot water heaters (both standard (gas or electric) and tank-less styles) and boilers
  • MAINTAINS EFFICIENCY: By inhibiting scale buildup on heat elements, helps maintain water heater efficiency
  • EASY TO REPLACE: Easy change-out makes system maintenance easy
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The 3M™ Aqua-Pure™ Whole House Scale Inhibition Replacement Water Treatment Cartridge AP431 for the AP43SS was designed to reduce scale build-up on hot water-using appliances such as water heaters (standard and tank-less), clothes washers and dishwashing machines, and on plumbing fixtures like faucets, pipes, and shower heads. The AP431 is as easy to change-out as a light bulb.
Package Qty1
Used In BrandsAqua-Pure
Manufacturer's IdAP431
Advertised Size (in)10-3/4 x 2-3/4
Actual Size (in)8 3/4 inches (length) x 2 1/2 inches (outside diameter)
Actual Size (cm)22.23 x 6.35
Primary Filter MediaScale Reduction media
Filter Life (gallons)1500
Filter Life (liters)5677.51
Filter Life (months)6 months
Operating Pressure (psi)0 - 125
Operating Temperature (°F)40 - 100
Operating Temperature (°C)4.4 - 37.8
Maximum Temperature (°F)100
Flow Rate (gpm)10
Flow Rate (lpm)37.85
Fitting TypeNPT
Fitting Size (inches)3/4 inch
Country of ManufactureUnited States
Primary Filter MediaScale Reduction media

Reduced Contaminants

The AQUAPURE-AP431 reduces the following contaminants:

  • Hard Scale
  • Rust and Corrosion

The AQUAPURE-AP431 is comparable with the following part numbers

3P777 40161502
AP430 AP430SS
AP430-SS AP431
AP-431 AP43110
AP431-10 AP-431-10

The AQUAPURE-AP431 fits the following model numbers


Installation Guide

User Guide


  1. The 3M Aqua-Pure AP431 hot water system cartridge needs to be replaced every 3-6 months. The cartridge may need to be replaced sooner depending on your water quality and your water usage
  2. Shut off incoming water supply
  3. Open nearest hot water outlet for 10 seconds to relieve pressure
  4. Remove cartridge by unscrewing counterclockwise from tee
  5. Replace with new AP431 cartridge
  6. Turn on water supply