Explained: How to Choose a Whole House Water Filter?

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Choosing the right whole house water filter for your home can be very daunting. With so many options available, how should you ensure that a particular system is perfect for your place?

Besides, it is not always correct to trust others’ choices and recommendations. What may work for them may not suit you.

Hence it is essential to do your homework and select a whole house water filtration system that meets your standards.

Here is a list of a few questions that you should think through and answer before purchasing.

From your current water quality to your planned budget, these determinants will help you make a successful and quick decision.

Key Takeaways

These are the 4 essential steps for choosing a whole house water filter:

  1. Know the quality of your water supply by having it tested.
  2. Based on the test results, choose a filter capable of removing any contaminants and impurities that you want to get rid of. Tip: Look out for NSF testing and certifications.
  3. Choose the right system size based on your peak water usage. Too small of a system could result in water pressure drops throughout your entire home.
  4. Consider your budget and available space.

1. Knowing the Quality of Your Water Supply

It is very crucial to know the quality of your water before you buy a whole house water filter or any type of water filter in general. Unfortunately, not every whole house system is efficient enough to remove all the contaminants you might be facing. So, before you waste your money on an inefficient filter, clear this query right in the beginning.

Public City Water

Most of the public water supplies in the US are pretty safe. However, unfortunately, the EPA doesn’t regulate all the contaminants that might be present in your water.

So, it is imperative to test your water supply and know about the contaminants on your own before choosing a filter.

Private Well Water

On the other hand, private wells come with their own challenges. According to a few reports, many wells have harmful contaminants such as Coliform bacteria (i.e. E. coli). Besides, water from private wells is often sediment-laden and high in iron and other heavy metals/minerals.

Well with Well Cap

How to Test for Water Contaminants

If you receive water from a local utility, get a free report on water quality. You can either contact the authorities through their website or call them on their helpline.

However, you can also be more proactive and get your water professionally tested. Take a sample to a lab near your house and ask the experts to help you determine its quality.

The latter is also your only option when receiving water from your own well.

2. What Do You Want to Achieve?

Once you have received your water quality report, take a step further and determine the right type of whole house water filter you require and establish what you want to achieve with that unit.

There are different varieties of these systems available in the market. Since each of them tackles a unique contaminant, you should learn about them in detail. For example:

Chlorine Taste and Odor Removal Through Carbon Adsorption

Whole house activated carbon filtration systems are pretty common these days. If your water quality report shows high amounts of chlorine, gases, and chemicals, this filter type is best for you.

The carbon adsorption media uses crevices and pores to trap large and small organic particles and chemicals. These harmful contaminants can also be inhaled during baths or showers, and hence their removal is imperative for your health.

Sand and Dirt Removal Through Sediment Filtration

If your water comes from a private well, it may contain contaminants like sand, dirt, and scale particles. These substances may even cause your water to look cloudy and taste bad.

So, to remove them, whole house sediment filters are the best options. They contain cartridges that trap these unnecessary impurities and make your water look nice and clean.

Hard Minerals and Metals Removal

Does the final report indicate the presence of hard minerals and/or metals? If yes, you might be consuming this water for your daily use and letting it harm your skin, hair, and clothes. Hard water and water high in iron is also known to damage the entire plumbing system including home appliances.

But, you can solve the contamination problem with an efficient treatment system.

Water softeners are most commonly used for making hard water soft. They apply ion exchange to replace minerals such as magnesium and calcium with potassium or sodium. Moreover, they can also reduce a few other contaminants, primarily low levels of iron.

Speaking of, ferric iron or high concentrations of ferrous iron require a different kind of approach. Here, specialized iron filters come into play. They often combine pre-oxidation with certain kinds of filter media to eliminate contamination.

Other metals may require different filtration methods and filter media.

Lead Removal Through Oxidation-Reduction

Many whole house water filters use the oxidation-reduction method to get rid of heavy metals like lead. Unfortunately, these metals are immensely harmful for the human body when consumed. KDF is the most famous filter media based on oxidation-reduction.

Lead can also be removed using a whole house reverse osmosis water filter system. While this purification method is expensive, in some cases it’s the only option and the results produced are worth an investment.

The last step is to find the whole house water filter that will meet your requirements.

Type: What Does the Filter Remove?

As mentioned above, if you want to get rid of cloudy texture, choose a whole house water filter that follows the sediment filtration process. Similarly, if you are dealing with elevated chlorine levels, getting a filter based on activated carbon would benefit you.

Simply put, you need to understand the problem with your water first and then buy a whole house filter that can help you solve the issue.

Big Blue Whole House Water Filter

NSF Certifications

The NSF, or National Sanitation Foundation, is an organization that creates many safety and health standards to benefit public health. So, an NSF-certified whole house water filter is an adequately tested and reliable system.

While it isn’t compulsory, you should always try to choose a filter owning such a certification. You can look for systems that come with seals. These labels signify their high quality and approval from authorities.

People & Bathrooms: Can the Filter Provide Enough Water to Meet Your Demand?

You expect a whole house water filter system to supply filtered water for your bathrooms, kitchen, washing machine, and other water-using appliances.

That said, you also want everyone to experience smooth water pressure and flow even on peak usage hours.

According to estimations,

  • A toilet utilizes 2.2 to 5.0 gallons per flush. If the toilet is old, it can use almost 7 gallons.
  • Your showerhead and bathtub tap use around 2.5 gallons of water every minute.
  • If you have a dishwasher, expect it to use between 6 and 16 gallons per load. A washing machine uses around 25 gpl.

Therefore, choosing a whole house water filter with a reasonable service flow rate is mandatory. Moreover, knowing the above data will help you find a unit that can fulfill your demand.

If you are a small or average-sized family, choose a filtration system with an 8 to 12 gpm flow rate. However, if you have many people living in your house with multiple baths, a flow rate of 15 gpm and above may be required.

You can also select the correct flow rate for your use by calculating your daily water consumption online. This estimate will give you an idea of how much water you require to lead a comfortable life every day.

Why is this important? A filter system with inadequate flow will drop the water pressure and possibly even bleed contaminants.

Micron Ratings and Flow Rates

If you want to install a filter to remove sand, dust, and silt only, you could get a sediment filter with a 50-micron rating. This number indicates the system’s capability to eliminate particles with a minimum size of 50 microns.

You also find whole house filters with micron ratings of 25, 10, 5, 1, etc. A system with a lower rating is considered more efficient in removing more and smaller contaminants.

However, there is a big dilemma attached to this concept. Filters with small micron ratings may not produce adequate water flow and pressure.

This is quite a bummer, and that’s why you won’t find any whole house reverse osmosis systems without pumps to boost water pressure. FYI: Reverse osmosis membranes have a micron rating of as low as 0.0001.

Does It Fit Your Budget?

When selecting a whole home water filter, consider all the costs related to the purchase. These include the initial price tag, installation fees, and maintenance expenses.

Since the filters are big, they are mostly expensive. At the same time, they can serve you for long.

For instance, systems with huge tanks are more costly, but they can filter as much as 1,000,000 gallons of water throughout their lifetime. Above that, they often require little maintenance, which saves you lots of cash.

On the flip side, most house filters based on cartridges are small and have low upfront cost. But they require replacement every few months, which isn’t great for your pocket long-term.

Do You Have the Space to Accommodate a Whole House Filter?

Whole house filtration systems are bigger than point-of-use filters, making it easy for them to distribute water around your place. In order to accommodate one adequately though, make sure you have enough space for installation and maintenance.

You can either install your filter outside or inside. Internal installation will certainly protect your system against external elements and environmental factors. Also, an inside space will make it easy for you to carry out any service tasks.

In most cases, the best location is close to where the main water line enters your home, upstream of other appliances, especially water heaters.

If you have any questions about how to choose a whole house water filter please don’t hesitate to leave a comment below!

About the Author Gene Fitzgerald

Gene Fitzgerald is one of the founders of BOS and currently head of content creation. She has 8+ years of experience as a water treatment specialist under her belt making her our senior scientist. Outside of BOS, Gene loves reading books on philosophy & social issues, making music, and hiking.
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Leave a Comment:

Pat says April 26, 2023

Isa Wi-Fi water refiner worth the extra money?

    Gene says April 27, 2023

    Hi Pat,
    This is mainly a question of personal preference I’d say. Many whole house water filters these days come with Bluetooth which is another solution.
    Personally, I wouldn’t worry about Wi-Fi too much.

Michael Grant says August 26, 2023

Any particular whole house brands for city water you recommend the most without concern of budget. I am leaning towards SpringWell due to initial research but there are so many out there.

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