How Does a Water Filter Work?

Refrigerators have come a long way from simply cooling and preserving food. Today, many models come equipped with water dispensers and ice makers, which offer clean water and ice cubes at the touch of a button.

But how does this water stay clean and safe to drink? Enter the refrigerator water filter. These small but powerful devices play a crucial role in removing contaminants from your water, ensuring it’s safe, refreshing, and great-tasting. In this article, we’ll break down how refrigerator water filters work, why they’re essential, and how to maintain them for optimal performance.

Why Do You Need a Refrigerator Water Filter?

Municipal water often contain contaminants like chlorine, lead, sediment, and even traces of agricultural chemicals. These can affect the taste and odor of water and pose potential health risks over time. Refrigerator water filters provide an extra layer of purification, catching impurities and delivering clean water straight to your glass.

The Basics: How a Refrigerator Water Filter Works

Refrigerator water filters use a combination of materials and technologies to remove contaminants from water. Here’s how the process typically works:

• Pre-Filtration: Water enters the filter through the refrigerator’s water supply line. At this stage, large particles like sediment or rust are caught and prevented from moving further into the filter. This initial filtration helps protect the filter and improve the effectiveness of later stages.
• Activated Carbon Filtration: Activated carbon, often made from charcoal, is the star of most refrigerator water filters. Carbon has a porous structure that attracts and traps contaminants. When water passes through the carbon layer, unwanted substances like chlorine, pesticides, and volatile organic compounds (VOCs) are absorbed, leaving cleaner water behind.
• Micron Filtration: Many refrigerator filters also use micron-rated filtration to catch smaller particles. Micron ratings indicate the size of particles the filter can capture. A lower micron rating means finer filtration. Refrigerator filters typically have ratings between 0.5 and 1 microns, effectively capturing tiny particles like sand, dirt, and microorganisms.
• Electrochemical Adsorption (in Some Models): Advanced filters may use additional layers with special materials to remove heavy metals like lead and mercury. Electrochemical adsorption layers work by attracting metals at a molecular level, making the water even safer for drinking.
• __Final Flow to Dispenser or Ice Maker: Once water is filtered, it flows directly to the dispenser or ice maker. Each time you press the lever for water, the refrigerator delivers freshly filtered water, free of many common contaminants.

What Contaminants Are Removed by a Refrigerator Water Filter?

Different filters remove different types of contaminants, but most refrigerator filters are designed to handle:

• Chlorine: Used in water treatment, but it can make water taste and smell unpleasant.
• Lead: A toxic metal that can leach from old pipes and pose health risks, especially to children.
• Heavy Metals (such as mercury): Some filters can remove or reduce the presence of toxic metals.
• Sediment: Particles like sand, dirt, and rust, which may give water a gritty texture.
• Pesticides and Herbicides: Traces of agricultural chemicals can end up in drinking water; filters can reduce these.
• Microorganisms: While most municipal water is treated to kill pathogens, filters with smaller micron ratings can further reduce bacterial content.

It’s worth noting that not all filters are created equal. Check the certifications on your refrigerator filter to see which contaminants it’s designed to remove. Look for NSF/ANSI Standard 42 certification for chlorine reduction and Standard 53 for heavy metals and health-related contaminants.

How Often Should You Replace Your Refrigerator Water Filter?

Regular replacement is key to maintaining effective filtration. Most refrigerator manufacturers recommend changing the filter every six months. However, the frequency can vary depending on:

• Water Quality: If your tap water is harder or has a higher level of contaminants, the filter will work harder and wear out faster.
• Usage: Larger households with higher water consumption may need to replace filters more frequently.

A good rule of thumb: if the water starts tasting different, smelling odd, or if the water flow slows down, it’s likely time to change the filter.

What Happens If You Don’t Replace Your Refrigerator Water Filter?

Skipping filter replacements can lead to several issues:

• Decreased Water Quality: As the filter becomes clogged with contaminants, its effectiveness decreases, meaning more impurities make it into your drinking water.
• Reduced Flow Rate: A clogged filter can slow down the water flow to the dispenser and ice maker, making it less convenient to use.
• Potential Bacterial Growth: Over time, the filter may become a breeding ground for bacteria, which can contaminate the water and lead to unpleasant tastes or odors.
• Wear on Your Refrigerator: Blockages in the filter can put extra pressure on the refrigerator’s water system and valves, potentially causing wear and tear that might reduce the appliance’s lifespan. If you encounter a failure in water system components, schedule refrigerator repair service to have the problem fixed by a professional.

Choosing the Right Filter for Your Refrigerator

When replacing your refrigerator water filter, check the model number and specifications recommended by your fridge’s manufacturer. Using the correct filter ensures compatibility and maintains warranty coverage. Some filters are compatible with multiple brands, but it’s best to stick to approved or certified filters to ensure proper function.

Visit our Sears PartsDirect website to find and order the right filter for your refrigerator. Set up a subscription to have a new filter shipped to your home every 6 months for your convenience.

How to Replace Your Refrigerator Water Filter

Replacing a refrigerator filter is usually a straightforward process:

1. Locate the Filter: Most filters are found either in the base grille at the front, inside the fridge door, or at the top corner inside the fridge.
2. Turn Off Water Supply: This step isn’t always necessary, but it’s good to check the user manual for any specific instructions. Some filters are easier to remove when you turn off the water supply and dispense a little water to release pressure on the water filter housing fitting.
3. Remove the Old Filter: Depending on the model, you may need to twist, pull, or unlock the filter.
4. Insert the New Filter: Make sure it’s properly aligned and secured.
5. Flush the Filter: Run water through the dispenser for several minutes to remove any carbon dust or particles and prepare the filter for use. This will also remove air from the water supply lines in your fridge. Trapped in the water supply lines can cause the water dispenser to drip water.
6. Reset the Indicator Light: Some refrigerators have an indicator light that tells you when it’s time to replace the filter. After replacing it, reset the light according to the instructions in your user manual.

Here’s a video that shows you how to remove one of the most common refrigerator water filters:

Refrigerator water filters are a simple yet powerful tool for ensuring clean, safe drinking water. By understanding how they work and maintaining a regular replacement schedule, you can enjoy refreshing water and ice that’s free from many of the common contaminants found in municipal water supplies.

In addition to replacing your refrigerator water filter regularly, keep your refrigerator and its water system in top shape by scheduling annual refrigerator maintenance by a professional technician. Our technicians will visit your home to clean, inspect and maintain every part of your fridge to keep it working safely and smoothly all year long.