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How Often To Change Your Water Filter


What’s the best way to keep your water tasting great all the time — from the minute you install a drinking water system to months or years later? Simple: replacing your water filter. The key is to do this on a regular basis, and it all comes down to the manufacturer’s guidelines.

If you wait too long, you run the risk of the water filter not functioning as intended, possibly reducing the water quality. However, if you buy replacements too frequently, you could be wasting perfectly good filters.

Here’s what to know about taking care of your water filtration system so it can take care of you.

When To Replace Your Water Filter

To make it easier to remember when to change your water filters, our Culligan engineers have determined time frames for all of our water filtration products. Recommendations for your particular filter system will always come with your Owner’s Guide. On top of that, your local Culligan® expert also knows your local water conditions, so they can work with you to recommend a schedule based on your water quality and usage.

Here are a few examples:

Whole-Home Water Filtration Systems

Culligan’s whole-home water filtration systems treat your water supply from every faucet, helping catch problem water issues such as iron and sediment. Instead of traditional filters, these systems use filtration media that should be replaced regularly:

  • Cullar® Filter: This filter can last for several years and only needs professional replacement when it less effectively addresses chlorine tastes and odors.
  • Filtr-Cleer®: This filter also has a several-year lifespan. However, if you notice a drop in water pressure, you may need a replacement filter.
  • Cullneu® Filter: Because media is consumed in the water pH neutralization process, these filters require periodic replenishment.
  • Iron-Cleer® Filter: In most applications, this iron filter can also last several years.
  • Sulfur-Cleer® Filter: While periodic cleaning may be necessary, this filtration solution can last for years without needing replacement.
  • Arsenic Reduction Filter®: You should have regular water tests to check how effectively this filter is reducing arsenic content. Based on the results, your local Culligan expert can tell you when it’s time to replace the filter media.

Reverse Osmosis Water Filtration Systems

Reverse osmosis (RO) water systems use a specialized, multi-stage process to treat your drinking water. The main difference from other types of filtration is the RO membrane, a semi-permeable, net-like material that traps certain contaminants and lets the rest of your water flow through.* Naturally, this membrane is exhausted over time, so it needs to be replaced. Some systems even have smart settings that enable you to check filter and membrane life right from your faucet or smartphone.

Here’s an inside look at one of these systems, Culligan’s Aquasential Smart RO®, and the recommended replacement time frames for its various filters and media:

  • Sediment/Carbon Combination Prefilter: The lifespan for this filter is one to two years.
  • RO Membrane: This membrane’s capacity is 75 gallons per day (gpd). It typically lasts three to five years, though varying chlorine, sediment or TDS levels may affect replacement frequency..
  • Specialty Cartridges: The Specialty Total Defense, Specialty Total Defense with Mineral, Specialty Remineralization and Specialty Arsenic cartridges can last either one year/1,000 gallons or two years/2,000 gallons depending on what filter life option you choose.
  • Postfilter: Both the One-Year and Advanced Postfilters last one year/1,000 gallons or two years/2,000 gallons, also depending on your filter life choice.

Other Filter Systems

When you count on Culligan solutions, you don’t have to worry about needing a filter change every few months. But how do other filtration systems compare? Here are a few examples:

  • Refrigerator filters: Some people don’t realize that a fridge water filter ever needs to be changed, but manufacturers generally recommend replacements every six months. Often costing $50 or more per filter, this can quickly add up — and all for a system that primarily addresses chlorine instead of countless other contaminants.
  • Pitcher filters: These filters seem quick and convenient, but they’re short-lived: You should replace the filters about every two months or 40 gallons. On top of that, a pitcher filter generally isn’t certified to reduce a wide variety of contaminants.
  • Faucet filters: Depending on how many people are in your household and how much water you use from a single faucet, you may need to replace this filter every three months (or every six months maximum).

Although these options may have surprisingly affordable prices, remember to consider the total cost of ownership — and what you’re really paying for. For most people, it makes more sense to buy a more comprehensive system that addresses more contaminants, works faster and requires fewer filter replacements.

How To Replace Your Water Filter

Every water filtration system comes with its own directions, recommendations and requirements. While you may be able to buy filters for simpler systems at your local home improvement or grocery store and install them yourself, whole-home and RO filtration solutions are best handled by water professionals.

That’s because your local Culligan expert knows exactly what kind of filter cartridge or media you need, where to install it and what to do with the old filter. Smart systems can even notify you or your Culligan partner that maintenance, replacements or repairs are required.

Why Water Filter Lifespans Matter

Water filter cartridges or filtration media do much of the real work when it comes to ensuring water quality. Over time, they become less effective; for example, some act like sponges and can get “full” when absorbing contaminants, while others are more like nets and eventually become less restrictive. When this happens, your “filtered water” is no longer quite so filtered, and that can lead to unpleasant tastes, odors and more.

To maintain performance and reliability, manufacturers recommend specific time frames for replacing water filters. These time frames are based on a few details, such as the type and design of your water system, but the most important variable is water usage. Naturally, this depends on the number of people in your household and your water needs — and it can be difficult to keep up with all of those factors.

That’s why it’s smart to:

  • Brush up on manufacturer recommendations
  • Make a note when you replace your water filter
  • Mark your calendar or set a phone reminder for regular replacements

Smart filtration systems can keep track of this information for you, making it even easier to stay on top of maintenance.

Other Considerations for Water Filter Replacement

Although it’s smart to stick to manufacturer recommendations as much as possible, there are a few situations where you should actually break those rules.

For example, if any water filter system seems to stop working before the filter lifetime is up, you could have a problem. Look for changes in the taste, odor or color of your tap and drinking water, as any of these could indicate that your filter needs early replacement or your system needs service.

The same is true any time there’s a water service interruption or a “boil advisory” issued for your area. These incidents can impact water quality and may leave potentially harmful contaminants in your filters, so contact your local Culligan expert for advice and next steps.

Additionally, it’s important to note that manufacturer recommendations are based on assumptions and averages. Varying levels of contaminants and water usage can affect how often you will need to replace your filter. Some contaminants, such as iron, can wear down an RO membrane especially quickly — and that’s where a water test comes in handy.

Water quality tests help determine what’s present in your water and in what amounts. This doesn’t just tell you what you’re drinking, cooking, cleaning and bathing with; it also helps your Culligan expert understand how water quality could impact filter life. For example, if you notice a significant decrease in filter life, a water test can help determine if something has changed or if a particular contaminant is causing more trouble than usual.

Get Help With Your Water Filter

Whether you’re looking for a comprehensive, cost-effective new water filtration system or just want to know how to care for your current one, you’re in the right place. It’s important to learn everything you can about water treatment so you make the best decisions for your home and family.

That all begins with a water test. You’ll see hardness levels, potential contaminants, recommended solutions and more — all in 30 minutes or less.

Get started today — schedule your free, in-home water test and consultation.

*Contaminants may not be present in your water.

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