Big Blue 20-in Heavy Duty Water Filter Housing - High Flow Design

In this review the Pentair Pentek Big Blue 20-in heavy duty filter housing is assessed for homeowners and light commercial users who need large-capacity sediment or carbon filtration with minimal pressure drop. The single biggest reason to consider it is capacity: the extra-large sump accepts 4-1/2 in diameter, 20-in cartridges so fewer vessels are required for high flow applications. The review highlights practical installation notes, materials compatibility, and customer-reported durability so buyers know what to expect before fitting it into a whole-house system.

Key Features

• Extra-large sump: The 20-in length provides greater cartridge capacity so systems can handle higher flow rates with fewer housings.
• High-Flow Polypropylene cap: The HFPP cap and 1 in NPT ports improve flow handling and reduce pressure drop on heavy-sediment lines.
• Multiple port sizes available: Cap options include 3/4 in, 1 in or 1-1/2 in inlet and outlet ports to suit a range of plumbing setups and flow needs.
• Chemical compatibility: The polypropylene construction is compatible with a broad range of common treatment chemicals used in residential and light industrial filtration.
• Pressure relief option: Available with a pressure relief button that makes cartridge changes easier and safer by relieving trapped pressure.

Who It's For

The Big Blue 20-in housing is best for homeowners, landlords or small commercial sites that need whole-house sediment or carbon filtration with high flow capacity. It suits systems where reducing vessel count and keeping pressure drop low are priorities, for example well water or municipal feed lines serving multiple fixtures.

Those who should look elsewhere include users requiring specialty media housings smaller than 4-1/2 in diameter, or applications needing stainless steel wetted parts for aggressive chemistries. If ultra-long-term outdoor exposure is expected, consider additional weather protection or an alternative material choice due to mixed long-term durability feedback.

Pros & Cons

Pros

• Large 20-in sump significantly increases cartridge capacity, reducing paired housings for high flow systems.
• HFPP cap and 1 in NPT ports help maintain flow with minimal pressure drop in typical installations.
• Good chemical compatibility and availability of a pressure relief button make maintenance easier.

Cons

• Some customers reported long-term splitting after several years of service, so outdoor or extreme conditions may affect lifespan.
• Hardware and fittings are not always included in every purchase, so buyers should verify what is supplied before installation.

Specifications

Our Verdict

The Big Blue 20-in housing is a practical, cost-effective choice for whole-house or light commercial filtration where high flow and large cartridge capacity matter. It offers reliable flow performance and sensible service features, and represents good value for DIY installers and facilities managers, though buyers should account for installation fittings and consider environmental protection for the longest service life.

Frequently Asked Questions

Can this housing accept standard 20-in cartridges?
Yes, it accepts a wide variety of 4-1/2 in diameter, 20-in cartridges used for sediment and carbon filtration.

Does the housing include a pressure relief button?
Some versions are supplied with a pressure relief button; check the specific configuration to confirm inclusion.

What inlet/outlet sizes are available?
The HFPP cap is available with 3/4 in, 1 in or 1-1/2 in NPT inlet and outlet ports to match plumbing needs.