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3M Aqua-Pure AP431 Hot Water Heater Scale Inhibitor Filter

Price $43.99 List Price Price $62.99 Save 30%
Availability: In Stock
Choose a quantity
  • 1Filter$43.99 
  • 3Filters Price $41.39 each
  • 6Filters Price $39.59 each
The 3M Aqua-Pure AP431 Hot Water System Scale Inhibitor Replacement Cartridge will extend the life of your hot water heater by stopping scale buildup and corrosion. The filter not only increases the efficiency of your hot water systems so they run cleaner, but it also saves money on maintenance costs. The 3M Aqua-Pure AP431 hot water system protector filter cartridge is designed for use with the 3M Aqua-Pure AP430 Hot Water System.
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
Outside Diameter (inches)2.5
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