1. Carbon Filters
  2. 20" x 4.5" Carbon Block Water Filter Cartridges

4.5 x 20 Carbon Water Filter

Discover All Filters’ wide range of 20 x 4.5 carbon water filter cartridge replacements, designed to improve water clarity, taste, and quality. The Carbon Block Series uses coconut shell powdered activated carbon formed into a carbon block for fine filtration and chlorine reduction, while the CC1 Series features catalytic carbons to reduce chloramines and other contaminants. For general-purpose drinking water filtration, the GAC Series filters offer versatile granular activated carbon, and the RFC Series provides efficient radial flow design and a low pressure drop. The C1 Series and NCP Series combine carbon with non-cellulose polyester media for durability, sediment control, and reliable chemical reduction.

Carbon Filter Cross Reference Chart

Size

Rating

SpiroPure

Pentek

Hydronix
Carbon Block Series

Carbon Block Series

Bonded PAC

4.5" x 20"

  • 0.5 micron

  • 1 micron

  • 5 micron

  • 10 micron
Catalytic Carbon

CC1 Series

Catalytic Carbon

4.5" x 20"

  • 1 micron
GAC Series

GAC Series

Granular Activated Carbon

4.5" x 20"

  • 20 micron
RFC Series

RFC Series

Radial Flow Carbon

4.5" x 20"

  • 25 micron
C1 Series

C1 Series

Carbon Impregnated Non-Cellulose Polyester

4.5" x 20"

  • 5 micron
NCP Series

NCP Series

Carbon Impregnated Non-Cellulose Polyester

4.5" x 20"

  • 10 micron

Compatible 20 x 4.5 Water Filter Cartridges

Use our cross-reference chart to find the right carbon filter for your specific system. Start by finding the make and model number of your current filter in the chart, then check across the row to find compatible SpiroPure replacements. If your model number isn’t available, you can also search by filter size and micron ratings, and compare specifications to find the right filter. Here are some of the uses of each series:

  • Carbon Block Series: Designed for fast and efficient removal of contaminants, Carbon Block Series 4.5 x 20 carbon block filters are ideal for drinking or cooking water, such as in restaurants or home countertop or under-sink systems.
  • CC1 Series: CC1 Series 20 x 4.5 water filter cartridges can be ideal for uses like whole-house water systems, aquariums, and commercial kitchens.
  • GAC Series: Made with coconut shell filter material, GAC Series filters are often used in commercial kitchens, whole-house, under-sink, and countertop systems.
  • RFC Series: RFC carbon filters are commonly used in commercial kitchens, restaurants, and whole-house water systems, as they provide effective chlorine, taste, and odor reduction.
  • C1 Series and NCP Series: Designed for long-lasting chemical and odor reduction, C1 and NCP Series filters are used in whole-house systems, commercial kitchens, reverse osmosis (RO) pre-filtration, and light industrial applications.

Order 20 x 4.5 Water Filter Cartridges

Upgrade your water filtration system with carbon block filters from All Filters. Enjoy friendly and reliable customer service on live chat, email, or phone 7 days a week. Orders over $99 and most Super Value deals come with free shipping. Order 4.5 x 20 carbon block filters online today and enjoy high-quality filters at affordable prices.

FAQs on 4.5 x 20 water filter

Can I use a 4.5 x 20 carbon block filter for my whole-house filtration system?

Yes! 20x4.5 carbon cartridges are an excellent choice for whole house systems, especially for single family homes that require more water usage. Just make sure you have a 20” BB filter housing in your system to fit a 20x4.5 filter.
Replacement times for your 4.5x20 carbon filter will depend upon water quality, usage, media type, and other factors. Generally, you will replace your cartridge every 6-12 months or when you notice a decrease in water flow or a change in taste or odor.
The larger 20x4.5 carbon filter cartridge makes it excellent for reducing chlorine taste and odor and other unwanted chemicals for a variety of applications, including whole house water filter systems, pre-filters for RO systems and other under sink filters, commercial applications, and point-of-entry filtration such as for certain appliances.
Installation can vary by cartridge type, but for most 20x4.5 carbon filters you will simply open the water filter housing, remove the old filter housing, and insert the new filter cartridge. You will then reinstall the filter housing following manufacturer recommendations for your filter system.
Carbon block filters are composed of powdered activated carbon that has been compressed with heat and pressure into a solid block. This enhances filtration by increasing contact time of the water with the carbon fibers, and also results in less channeling of water through the media.

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