Pentek - GAC-20BB - 20" x 4.5" Granular Activated Carbon Filter
GAC-20BB 20" x 4.5" Granular Activated Carbon Filter
High-capacity carbon filtration for whole house, commercial, and well water systems requiring chlorine, taste, and odor reduction with minimal pressure drop
The Pentek GAC-20BB uses a full-length granular activated carbon bed with forced-contact flow path to maximize chlorine removal and reduce taste and odor throughout the entire 25,000 gallon service life. A permanently fastened 20-micron spun polypropylene post-filter captures carbon fines before water exits the cartridge, while an internal expansion pad prevents channeling and media bypass. Rated for 4 GPM at 5 psi pressure drop, this filter fits standard 20" x 4.5" Big Blue housings.
Engineered for Maximum Carbon Contact
Full-Length Flow Path
Water enters one end and travels through the entire carbon bed before exiting, ensuring maximum contact time and adsorption efficiency
20-Micron Post-Filter
Spun polypropylene filter permanently fastened to support basket captures carbon fines and suspended particles before discharge
Anti-Channeling Design
Internal expansion pad minimizes media migration and water bypass, maintaining consistent filtration throughout the cartridge life
High Flow Performance
Delivers 4 GPM with only 5 psi pressure drop, suitable for residential whole house and light commercial applications
Wide Temperature Range
Rated for 40°F to 125°F operation with polystyrene end caps, Buna-N and Santoprene gaskets for secure sealing
General Purpose Filtration
Effectively reduces chlorine taste and odor, unpleasant tastes, and organic contaminants for improved drinking water quality
Technical Details
| Model Number | GAC-20BB (Pentek 155249-43) |
| Dimensions | 20" x 4.625" (4-5/8") |
| Filter Media | Granular Activated Carbon (GAC) |
| Post-Filter Micron | 20 micron |
| Flow Rate | 4 GPM at 5 psi pressure drop |
| Capacity | 25,000 gallons at 4 GPM |
| Temperature Rating | 40°F to 125°F |
| End Cap Material | Polystyrene |
| Gasket Type | Buna-N (top), Santoprene (bottom) |
| Housing Compatibility | 20" x 4.5" Big Blue housings |
System Fit and Use Cases
The Pentek GAC-20BB fits all standard 20-inch x 4.5-inch Big Blue filter housings. Ideal for whole house water filtration systems, point-of-entry well water treatment, commercial applications requiring chlorine reduction, and any installation where taste, odor, and chlorine removal is needed at flow rates up to 4 GPM. Replace every 25,000 gallons or when taste and odor breakthrough occurs. Compatible with Pentek, Pentair, and other manufacturers' 20" Big Blue housings using standard gasket seals.
Pentek has manufactured reliable water filtration cartridges for residential, commercial, and industrial applications for decades. The GAC-20BB is made in the USA with quality materials and consistent performance standards.
GAC-20BB 20" x 4.5" Granular Activated Carbon Filter
High-capacity carbon filtration for whole house, commercial, and well water systems requiring chlorine, taste, and odor reduction with minimal pressure drop
The Pentek GAC-20BB uses a full-length granular activated carbon bed with forced-contact flow path to maximize chlorine removal and reduce taste and odor throughout the entire 25,000 gallon service life. A permanently fastened 20-micron spun polypropylene post-filter captures carbon fines before water exits the cartridge, while an internal expansion pad prevents channeling and media bypass. Rated for 4 GPM at 5 psi pressure drop, this filter fits standard 20" x 4.5" Big Blue housings.
Engineered for Maximum Carbon Contact
Full-Length Flow Path
Water enters one end and travels through the entire carbon bed before exiting, ensuring maximum contact time and adsorption efficiency
20-Micron Post-Filter
Spun polypropylene filter permanently fastened to support basket captures carbon fines and suspended particles before discharge
Anti-Channeling Design
Internal expansion pad minimizes media migration and water bypass, maintaining consistent filtration throughout the cartridge life
High Flow Performance
Delivers 4 GPM with only 5 psi pressure drop, suitable for residential whole house and light commercial applications
Wide Temperature Range
Rated for 40°F to 125°F operation with polystyrene end caps, Buna-N and Santoprene gaskets for secure sealing
General Purpose Filtration
Effectively reduces chlorine taste and odor, unpleasant tastes, and organic contaminants for improved drinking water quality
Technical Details
| Model Number | GAC-20BB (Pentek 155249-43) |
| Dimensions | 20" x 4.625" (4-5/8") |
| Filter Media | Granular Activated Carbon (GAC) |
| Post-Filter Micron | 20 micron |
| Flow Rate | 4 GPM at 5 psi pressure drop |
| Capacity | 25,000 gallons at 4 GPM |
| Temperature Rating | 40°F to 125°F |
| End Cap Material | Polystyrene |
| Gasket Type | Buna-N (top), Santoprene (bottom) |
| Housing Compatibility | 20" x 4.5" Big Blue housings |
System Fit and Use Cases
The Pentek GAC-20BB fits all standard 20-inch x 4.5-inch Big Blue filter housings. Ideal for whole house water filtration systems, point-of-entry well water treatment, commercial applications requiring chlorine reduction, and any installation where taste, odor, and chlorine removal is needed at flow rates up to 4 GPM. Replace every 25,000 gallons or when taste and odor breakthrough occurs. Compatible with Pentek, Pentair, and other manufacturers' 20" Big Blue housings using standard gasket seals.
Pentek has manufactured reliable water filtration cartridges for residential, commercial, and industrial applications for decades. The GAC-20BB is made in the USA with quality materials and consistent performance standards.
Description
GAC-20BB 20" x 4.5" Granular Activated Carbon Filter
High-capacity carbon filtration for whole house, commercial, and well water systems requiring chlorine, taste, and odor reduction with minimal pressure drop
The Pentek GAC-20BB uses a full-length granular activated carbon bed with forced-contact flow path to maximize chlorine removal and reduce taste and odor throughout the entire 25,000 gallon service life. A permanently fastened 20-micron spun polypropylene post-filter captures carbon fines before water exits the cartridge, while an internal expansion pad prevents channeling and media bypass. Rated for 4 GPM at 5 psi pressure drop, this filter fits standard 20" x 4.5" Big Blue housings.
Engineered for Maximum Carbon Contact
Full-Length Flow Path
Water enters one end and travels through the entire carbon bed before exiting, ensuring maximum contact time and adsorption efficiency
20-Micron Post-Filter
Spun polypropylene filter permanently fastened to support basket captures carbon fines and suspended particles before discharge
Anti-Channeling Design
Internal expansion pad minimizes media migration and water bypass, maintaining consistent filtration throughout the cartridge life
High Flow Performance
Delivers 4 GPM with only 5 psi pressure drop, suitable for residential whole house and light commercial applications
Wide Temperature Range
Rated for 40°F to 125°F operation with polystyrene end caps, Buna-N and Santoprene gaskets for secure sealing
General Purpose Filtration
Effectively reduces chlorine taste and odor, unpleasant tastes, and organic contaminants for improved drinking water quality
Technical Details
| Model Number | GAC-20BB (Pentek 155249-43) |
| Dimensions | 20" x 4.625" (4-5/8") |
| Filter Media | Granular Activated Carbon (GAC) |
| Post-Filter Micron | 20 micron |
| Flow Rate | 4 GPM at 5 psi pressure drop |
| Capacity | 25,000 gallons at 4 GPM |
| Temperature Rating | 40°F to 125°F |
| End Cap Material | Polystyrene |
| Gasket Type | Buna-N (top), Santoprene (bottom) |
| Housing Compatibility | 20" x 4.5" Big Blue housings |
System Fit and Use Cases
The Pentek GAC-20BB fits all standard 20-inch x 4.5-inch Big Blue filter housings. Ideal for whole house water filtration systems, point-of-entry well water treatment, commercial applications requiring chlorine reduction, and any installation where taste, odor, and chlorine removal is needed at flow rates up to 4 GPM. Replace every 25,000 gallons or when taste and odor breakthrough occurs. Compatible with Pentek, Pentair, and other manufacturers' 20" Big Blue housings using standard gasket seals.
Pentek has manufactured reliable water filtration cartridges for residential, commercial, and industrial applications for decades. The GAC-20BB is made in the USA with quality materials and consistent performance standards.
