Reverse osmosis filter components play a crucial role in providing clean, safe drinking water by removing various contaminants.

Reverse osmosis filter components include pre-filters, the RO membrane, post-filters, a storage tank, and a faucet. These components work together to remove contaminants, ensuring clean, safe drinking water. Optional features like a water storage tank, remineralization filter, pressure booster pump, UV disinfection light, and TDS monitor can enhance the RO filter’s performance.

This article explores the essential parts of a reverse osmosis system, including the filtration stages such as the sediment pre-filter, carbon filter, and reverse osmosis membrane. It also reviews other key components like the water supply connector, shut-off valve, check valve, drinking water faucet, drain line, and flow restrictor.

Let’s dive into the world of reverse osmosis filter components and learn more about their function and importance.

Read my articles on whole house reverse osmosis filters and under-sink reverse osmosis filters.

Reverse Osmosis Filter Components – Primary Pieces of Equipment

A reverse osmosis (RO) system is a popular water filtration method that effectively removes contaminants from your drinking water. To better understand how RO systems work, let’s examine the key parts of a reverse osmosis system and their functions:

Filtration Stages

Most residential RO filters have 4 stages of water treatment.

1. Sediment Pre-Filter

The sediment pre-filter, made of melt-blown polypropylene, removes dirt, rust, and sediment particles down to 5 microns. There are several types of sediment cartridges, including pleated filters, which offer increased surface area and longer life, and are washable and reusable. Melt-blown polypropylene filters are designed for removing dirt, rust, and sediment, with 5 and 20-micron options being the most popular for drinking water applications. Alternatively, string wound filters provide an affordable solution with various media types and a wide range of applications.

2. Carbon Pre-Filter

The carbon pre-filter uses a coconut shell carbon block cartridge with a 10-micron rating to remove chlorine, taste, odor, and chemical contaminants. Activated carbon block filters typically have a 0.5 to 10-micron filtration capability, which also helps with particulate filtration, removing taste and odor from chlorine, reducing insoluble lead, and in some cases, removing Giardia and Cryptosporidium. A 5-stage reverse osmosis system includes an additional carbon block cartridge in a third housing.

3. Reverse Osmosis Membrane

The thin-film composite (TFC) reverse osmosis membrane rejects 95% of total dissolved solids (TDS) down to 0.0001 microns. TFC membranes are semi-permeable and primarily used in water purification or desalination systems but also have applications in chemical processes such as batteries and fuel cells.

4. Post Carbon Filter

The post carbon filter, which uses coconut shell activated carbon, serves as the final polishing filter after the storage tank and right before water usage. Inline post filters typically attach to the top of a reverse osmosis system’s membrane housing, removing any remaining chlorine or contaminants missed by the other cartridges or membrane.

The following table summarizes the different filtration stages, filter types, their purpose, and micron ratings.

Filter Stage	Filter Type	Purpose	Micron Rating
Sediment Pre-Filter	Melt Blown Polypropylene	Removes dirt, rust, and sediment particles	5 – 20
	Pleated Filters	Increased surface area, longer life, washable, and reusable
	String Wound Filters	Affordable solution, various media types, and wide range of applications
Carbon Pre-Filter	Coconut Shell Carbon Block	Removes chlorine, taste, odor, and chemical contaminants	0.5 – 10
Reverse Osmosis Membrane	Thin Film Composite (TFC)	Rejects 95% of total dissolved solids (TDS)	0.0001
Post Carbon Filter	Coconut Shell Activated Carbon	Final polishing filter, removes any remaining chlorine or contaminants missed by other filters

Additional RO Filter Components

In addition to the primary equipment, your reverse osmosis filter system has additional components. These parts may vary by manufacturer, model, and options, but they are all commonly found in these water filters.

Pressure Booster Pump

A pressure booster pump increases water pressure to the RO system, ensuring optimal performance and efficiency.

Shut-Off Valve

The shut-off valve automatically stops the water flow when the storage tank is full, preventing overfilling and water waste.

Pressure Regulator

The pressure regulator helps maintain consistent water pressure in the RO system, preventing damage due to fluctuations in water pressure.

Check Valve

Located on the outlet side of the RO membrane, the check valve prevents backflow of water from the storage tank, protecting the membrane from potential damage.

Drinking Water Faucet

The dedicated drinking water faucet is installed at the sink, providing easy access to the filtered water.

Drain Line

The drain line carries wastewater containing contaminants filtered out by the RO system to the drain.

Flow Restrictor

The flow restrictor regulates the flow of water through the RO membrane, ensuring optimal filtration and prolonging the membrane’s lifespan.

Water Supply Connector

This component connects the RO system to your home’s water supply, allowing the system to access the water it will filter.

Optional RO System Components

Some RO filters have optional components to enhance their performance. Some common additions include:

Water Storage Tank

A water storage tank stores the filtered water, ensuring a continuous supply of clean water whenever needed.

Remineralization Filter

The remineralization filter adds healthy minerals like calcium and magnesium back to the filtered water, improving taste and balancing the water’s pH levels.

UV Disinfection Light

The UV disinfection light is an optional component that uses ultraviolet light to kill bacteria, viruses, and other microorganisms, further enhancing the water’s safety and quality.

TDS Monitor

A Total Dissolved Solids (TDS) monitor measures the concentration of dissolved solids in the water, providing an indication of water quality and filter performance.

The following table lists optional components, their value and benefits, and cost ranges.

Optional Component	Value and Benefit	Cost Range
Water Storage Tank	Stores filtered water, ensuring a continuous supply of clean water when needed	$50 – $260
Remineralization Filter	Adds healthy minerals like calcium and magnesium back to the water, improving taste and balancing pH	$40 – $300
Pressure Booster Pump	Increases water pressure to the RO system, ensuring optimal performance and efficiency	$150 – $500
Pressure Regulator	Maintains consistent water pressure in the RO system, preventing damage due to pressure fluctuations	$20 – $100
UV Disinfection Light	Kills bacteria, viruses, and other microorganisms, enhancing water safety and quality	$80 – $250
TDS Monitor	Measures dissolved solids concentration, providing an indication of water quality and filter performance	$125 – $510

Key Takeaways

RO systems consist of several stages, including sediment pre-filters, carbon pre-filters, and reverse osmosis membranes

Additional components ensure proper functioning and maintenance of the RO system

Optional components can enhance performance and water quality

Understanding the different components is crucial for selecting the best RO system for your needs

Final Take

A reverse osmosis system effectively filters drinking water through several stages, including sediment pre-filters, carbon pre-filters, and a reverse osmosis membrane. Additional components such as water supply connectors, shut-off valves, and post carbon filters play essential roles in maintaining the system.

Optional components like water storage tanks, remineralization filters, and UV disinfection lights can enhance performance and water quality. Understanding these components and their functions is crucial when selecting the best reverse osmosis system for your needs.