2-stage 20"x 4.5" Big Blue Whole House Water Filter
2-Stage 20" x 4.5" Big Blue Whole House Water Filtration System with Sediment and CTO Carbon Block Filters
Improve the water quality throughout your home, cottage, office, or light-commercial property with the Max Water 2-Stage Big Blue Whole House Water Filtration System.
This practical two-stage system combines sediment filtration and coconut-shell carbon block filtration to help reduce dirt, rust, suspended particles, chlorine, unpleasant taste, odor, and selected organic contaminants before the water reaches your faucets, showers, fixtures, and appliances.
The system uses full-size 20" x 4.5" Big Blue cartridges for greater dirt-holding capacity, longer service intervals, and higher flow potential than standard slim-line filter systems. Its 1" female NPT inlet and outlet ports make it suitable for many residential and light-commercial plumbing installations.
Two Stages of Whole House Filtration
- 5-Micron Polypropylene Sediment Filter
Part No. 104112 . Captures sand, rust, dirt, silt, and other suspended particles while helping protect the carbon block cartridge from premature clogging. - 5-Micron Coconut-Shell CTO Carbon Block Filter
Part No. 104114 . Reduces chlorine, unpleasant taste, odor, and selected organic compounds while providing finer filtration and final water polishing.
Why Choose a CTO Carbon Block Filter?
A CTO carbon block is made from compressed activated carbon. Its dense structure provides a consistent path through the media and helps improve contact between the water and the carbon surface.
Compared with loose granular carbon, a carbon block generally provides finer particle filtration and more uniform final polishing. This makes it a strong choice when chlorine, unpleasant taste, odor, and smaller suspended particles are the main concerns.
Pressure Gauge Monitoring
The included liquid-filled pressure gauge helps monitor system pressure and can assist with identifying changes in filtration performance.
A decline in pressure or water flow may indicate that the sediment or carbon block cartridge is becoming clogged and requires inspection or replacement.
Carbon exhaustion may not always create a noticeable pressure change. Replace the CTO cartridge when chlorine, unpleasant taste, or odor begins to return, or when its estimated service capacity is reached.
Key Features and Benefits
- Whole-house filtration: Treats incoming water before it reaches faucets, showers, fixtures, and appliances.
- Two essential filtration stages: Combines sediment protection and CTO carbon block treatment.
- Finer carbon filtration: The compressed carbon block provides consistent filtration and final water polishing.
- Chlorine, taste, and odor treatment: Helps improve the smell and taste of chlorinated water.
- Simple maintenance: Uses only two replacement cartridges for a straightforward service schedule.
- High-capacity Big Blue design: Uses standard 20" x 4.5" replacement cartridges.
- Durable opaque housings: Help protect the cartridges and water from light exposure during normal operation.
- 1" female NPT ports: Support higher-flow plumbing installations when correctly sized and installed.
- Double O-ring housing seals: Help provide a secure seal when correctly installed and maintained.
- Pressure-relief buttons: Help release trapped pressure before filter maintenance.
Helps Reduce
- Sand, silt, dirt, rust, and suspended sediment
- Chlorine taste and odor
- Unpleasant tastes and odors
- Turbidity caused by suspended particles
- Selected volatile organic compounds
- Selected pesticides and herbicides
- Selected trihalomethanes and organic chemicals
- Fine particles down to the cartridge's nominal 5-micron rating
Package Includes
- Two 20" x 4.5" Big Blue filter housings with double O-ring seals and pressure-relief buttons
- One 60 mm liquid-filled pressure gauge
- One 5-micron polypropylene sediment filter
- One 5-micron coconut-shell CTO carbon block filter
- One heavy-duty PVC ball valve
- One hex nipple fitting
- One filter housing wrench
- One heavy-duty two-stage steel wall-mounting bracket
- Installation hardware for the filtration bracket
- One-year manufacturer's limited warranty
Technical Specifications
| Specification | Value |
|---|---|
| System Type | Two-stage whole house sediment and CTO carbon block filtration system |
| Filter Cartridge Size | 20" x 4.5" Big Blue |
| Number of Filter Stages | 2 |
| Flow Direction | Right-side inlet to left-side outlet |
| Inlet and Outlet Connections | 1" female NPT |
| Sediment Filter Rating | 5 micron nominal |
| Carbon Block Rating | 5 micron nominal |
| Estimated Sediment Filter Life | Approximately 6 months* |
| Estimated Carbon Filter Capacity | Approximately 20,000–35,000 gallons* |
| Maximum Operating Pressure | 90 PSI |
| Recommended Operating Pressure | 20–60 PSI |
| Operating Water Temperature | 40–100°F / 5–38°C |
| Compatible Feed-Water pH Range | 4.0–10.0 |
| Maximum Feed-Water TDS | 2,000 ppm |
| Housing Pressure Drop | Less than 1 PSI at 20 GPM, excluding cartridge restriction* |
| Maximum Estimated Flow Rate | Up to 40 GPM with 1" inlet and outlet under suitable operating conditions* |
| Approximate Dimensions | 27.5" H x 16" W x 8" D |
| Approximate Weight | 32 lb. |
*Actual cartridge life, capacity, pressure drop, and flow rate depend on incoming water quality, sediment concentration, chlorine level, plumbing size, operating pressure, water temperature, flow demand, total water consumption, and cartridge condition. Maximum housing flow does not represent guaranteed contaminant-reduction performance at that flow.
TDS = Total Dissolved Solids.
Recommended Applications
- Residential whole-house water filtration
- Municipal and chlorinated city water supplies
- Homes with sediment, chlorine, taste, or odor concerns
- Cottages and vacation properties
- Offices and small commercial buildings
- Final carbon polishing for treated water
- Prefiltration before compatible reverse osmosis systems
- Prefiltration before compatible UV treatment systems
- Equipment and appliance protection
- Selected light-commercial water-treatment applications
Installation and Maintenance Information
- Install the system on the main cold-water supply line after the pressure tank, when applicable, and before the water heater.
- Connect the incoming water to the right-side inlet and the filtered water line to the left-side outlet.
- Install the sediment cartridge in the first housing and the CTO carbon block in the second housing.
- Confirm all directional flow markings before completing the plumbing.
- Support the system securely using the supplied steel bracket and suitable mounting hardware for the wall structure.
- Leave sufficient clearance beneath the housings for cartridge replacement and routine maintenance.
- Use suitable thread sealant or PTFE tape on NPT connections. Do not overtighten plastic ports or fittings.
- Shut off the incoming water supply and release system pressure before opening either filter housing.
- Lubricate O-rings only with food-grade silicone lubricant. Do not use petroleum-based lubricants.
- Flush both new cartridges thoroughly according to the product instructions before placing the system into normal service.
- Replace the sediment cartridge when flow declines, pressure drops, or the recommended service interval is reached.
- Replace the CTO cartridge when chlorine, unpleasant taste, or odor returns, or when its estimated service capacity is reached.
Frequently Asked Questions
Q. What does CTO mean?
A. CTO commonly refers to Chlorine, Taste, and Odor. The carbon block cartridge is designed to reduce chlorine-related taste and odor while providing additional fine-particle filtration.
Q. How is a CTO carbon block different from a GAC filter?
A. CTO filter uses compressed carbon media, while a GAC filter contains loose carbon granules. Carbon blocks generally provide finer and more uniform filtration, while GAC cartridges may provide lower flow restriction.
Q. Is this system suitable for municipal water?
A. Yes. This configuration is especially suitable for chlorinated city water where the primary concerns are sediment, rust, chlorine, unpleasant taste, and odor.
Q. Which cartridge should be installed first?
A. Install the sediment cartridge in the first housing on the inlet side. Install the CTO carbon block in the second housing so larger particles are removed before the water reaches the carbon stage.
Q. Can the two cartridges be replaced at different times?
A. Yes. The sediment cartridge may clog before the CTO media is exhausted. Replace each cartridge according to pressure, water flow, taste, odor, usage, and the recommended service interval.
Q. How can I tell when the sediment cartridge needs replacement?
A. Reduced flow or a noticeable drop in system pressure may indicate sediment loading. Shut off and depressurize the system before opening the housing and inspecting the cartridge.
Q. How can I tell when the CTO cartridge is exhausted?
A. Carbon exhaustion may not create a pressure drop. The return of chlorine smell, unpleasant taste, or odor may indicate that the cartridge needs replacement.
Q. Does the carbon block provide sediment filtration too?
A. Yes. The included carbon block has a nominal 5-micron rating, so it can provide additional fine-particle filtration after the first-stage sediment cartridge.
Q. Will this system reduce hard-water scale?
A. No. Sediment and carbon block cartridges do not remove calcium or magnesium and do not soften water. Hard-water concerns require an anti-scale system or a properly sized water softener.
Q. Does this system reduce TDS?
A. No. Sediment and carbon filtration do not substantially reduce TDS = Total Dissolved Solids. Reverse osmosis or another specialized process is required when TDS reduction is needed.
Q. Can this system remove iron or sulfur?
A. It is not a dedicated iron or sulfur treatment system. The sediment cartridge may capture some oxidized iron particles, but dissolved iron and hydrogen sulfide generally require specialized treatment selected after water testing.
Q. Can this system be installed before reverse osmosis equipment?
A. Yes. The sediment and carbon block stages can help reduce particles and chlorine before the water reaches compatible reverse osmosis equipment.
