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Tier1 RFC-20BB 20 X 4.5 Radial Flow Granular Activated Carbon Replacement Filter (25 micron)

Price $44.99 List Price Price $63.99 Save 29%
Availability: BackOrder
Fits most standard housings built for 20-inch x 4.5 inch filter cartridges
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  • 1Filter$44.99 
  • 3Filters Price $42.33 each
  • 6Filters Price $40.49 each
  • Ships fast!
  • Nominal 25 micron Radial Flow Carbon Water Filter Cartridge
  • Reduces chlorine taste and odor to provide better tasting water throughout your home
  • This cartridge features a unique design that reduces carbon fines in filtered water
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Tier1 RFC-20BB Filter Advantages

The RFC-20BB Whole House Filter Replacement Cartridge by Tier1 is an ideal water filtration solution. The unique design allows a greater reduction of carbon fines. If you have had significant issues with chlorine taste and odor the RFC-20BB whole house filter replacement cartridge by Tier1, will make your water taste great. This filter provides superior quality water compared to that of other aftermarket filters. This simple to install filter needs to be changed once every six months, or every 100,000 gallons whatever comes first. Be sure to order this affordably priced filter today!

Standardized Filter Sizing

The 20 X 4.5 granular activated carbon replacement filter by Tier1 is built to fit 20-inch x 4.5-inch filter housings. This standard sizing allows this filter to easily replace existing styles of whole house filters for housings requiring 20 x 4.5 inch filters. The RFC-20BB goes to work immediately providing cleaner, fresher and better tasting water for up to six months. Enjoy cleaner better tasting water with your whole house replacement filter today.

NOTE: Do not use with water that is microbiologically unsafe or of unknown quality without adequate disinfection before or after the system.

Package Qty1
Used In BrandsPentek
Manufacturer's IdRFC-20BB
Advertised Size (in)20 x 4-1/2
Actual Size (in)20 inches (Length) x 4.5 inches (Outside Diameter)
Actual Size (cm)50.8 x 11.43
MediaRadial Flow Granular Activated Carbon
Materials of ConstructionPorous Polyethylene
Filter Life (gallons)100,000
Filter Life (liters)378541
Filter Life (months)6 months
Micron Rating (Nominal)25
Operating Temperature (°F)40 - 125
Operating Temperature (°C)4.4 - 51.7
Maximum Temperature (°F)125
Flow Rate (gpm)4
Warranty GuaranteeUnconditional Guarantee for Life of the Product
IncludesOne Tier1 20 x 4.5 inch granular activated carbon replacement filter
Primary Filter MediaGranular Activated Carbon

Reduced Contaminants

The TIER1-RFC-20BB reduces the following contaminants:

  • Chlorine Taste & Odor
  • Rust and Corrosion

The TIER1-RFC-20BB is comparable with the following part numbers



  1. Turn off water supply. Press red pressure-relief button (if present)
  2. Unscrew housing. Remove large o-ring, wipe clean and set aside
  3. Discard used filter cartridge. Wash housing with dish soap and warm water using a nonabrasive sponge or cloth. Rinse thoroughly
  4. Fill 1/3 with water. Add about 1 tablespoon of bleach and scrub to disinfect. Rinse thoroughly
  5. Lubricate o-ring with clean silicone grease. Change o-ring if any damage cuts or degradation are present. Insert o-ring in groove
  6. NOTE: This step is important to ensure a proper housing seal. Make certain the o-ring is seated level in the groove
  7. Insert new filter cartridge
  8. Screw housing onto the cap and hand-tighten. Do not over tighten. Make sure cap standpipe slips into cartridge
  9. Turn on water supply. Press pressure-relief button (if present). Check for leaks before leaving installation