Whole House UV Water Filters: What You Need To Know Before You Buy

whole house uv water filters: a buyer's guide

Are you interested in buying a whole house UV water filter?

UV water filters can destroy up to 99.9% of harmful pathogens in your well or city water. I invite you to also read my guide on how whole house water filters work.

In this guide, I will go over…

  • Why invest in a whole house UV water filter
  • Pros and cons of UV filter systems
  • How do UV filtration systems work?
  • And some new technologies you should know about

Whole House UV Water Filter Installation: Is It Worth It?

The main reason for investing in a whole house UV water filter is to disinfect the water supply from microorganisms. Since it is installed right next to the main water shutoff, the clean and disinfected water will go throughout the entire home and not just a single fixture.

UV light has a very high effectiveness in removing microbes such as giardia, E coli, cryptosporidium, and other waterborne pathogens. The most common home use is to disinfect well water, but if you are in city water — it can be a huge safety feature.

If there is a power failure, water main break, or a suspected contamination… the city will issue a boil water advisory. Unfortunately by the time homeowners even get the boil water notice, there is a high chance the contaminated water is already inside the home’s piping. If you had a UV water treatment system, boiling your water is completely unnecessary.

Read Also: When The Whole House Water Filter Is Leaking From The Top?

How Does A Whole House UV Water Filter Work?

whole house uv water filters: a buyer's guide

The first step in a whole house UV water filter is when water enters the filter chamber. The UV light bulb is inside the chamber, and the bulb is protected by a clear quartz sleeve to prevent contact with the water.

The UV light is connected to an external power supply and ballast that is plugged into a wall outlet.

As the water swirls around in the chamber, the UV light irradiates the water supply — reaching a 99% disinfection rate. The UV radiation of wavelength 254 nm destroys bacteria and viruses by damaging their nucleic acids.

The water then leaves the UV water filter chamber and goes throughout the rest of the home.

Read Also: What Are The Best Iron Filters For Well Water?

What To Know About Whole House UV Water Filters

UV Water Filter Cost

These ultraviolet filtration systems typically cost around $400 to $800 for homeowners.

The installation from a qualified plumber can add another couple hundred to a $1,000 depending on the complexity.

Sediment Pre-filtration

UV water treatment systems are typically installed as the last filter just before water passes into the first home appliance like a water heater.

It is important to have a sediment filter installed prior to the UV water purifier otherwise it won’t work effectively and may not kill all microbes. Most UV water treatment systems require a sediment filter of at least 5-microns.

Water Chemistry

The effectiveness of ultraviolet light (known as UVT or ultraviolet transmittance) is based on the chemistry of your water. Water with a high hardness will impede the ability of the UV light to pass through and kill microbes.

Every manufacturer has their own minimum requirements for iron, turbidity, hardness, and other factors. If your water chemistry isn’t up to the specs of the manufacturer, you may be putting your water at risk of contamination.

How To Install A Whole House UV Filtration System

UV water purifiers ideally should be installed by a qualified plumber, but they can be done by a homeowner with some DIY skill.

You will need to secure the filter to a wall using the supplied brackets, connect it to the supply water line, and fasten the ballast or controller next to the filter. The UV lamp will need to be inserted into the steel chamber and secured.

whole house uv water filters: a buyer's guide

Whole House UV Water Filter Maintenance

UV filtration systems are usually made with low-pressure mercury lamps. The mercury vapor is a fuel source and it will eventually get used up. The biggest maintenance item for a UV water filter is to replace this UV lamp every 9k to 10k hours.

You will need to follow the manufacturer directions, but most UV lamps last about a year. And when you change the bulb, it is important that you do not touch the bulb with your fingers.

There is also a quartz sleeve that protects the bulb from water, and you will want to change this about every two years. You want to make sure that it stays clean and transparent.

How Long Do Whole House UV Water Purifiers Last?

With proper maintenance, a UV water filter should last for 15-20 years. The UV bulb will need to be replaced yearly, and the quartz sleeve bi-annually.

Read Also: What Are The Top Whole House Water Filter To Remove Chlorine And Fluoride?

Whole House UV Water Filters Pros and Cons

whole house uv water filters: a buyer's guide

PRO: No Chemicals

Whole house UV water filters don’t use any chemicals to treat the water, but a special frequency of ultraviolet light to kill microbes. So there aren’t any chemicals to mess with, and it won’t affect the taste or aesthetics of your water.

PRO: Easy Maintenance

The only real maintenance required is to change the bulb annually and to change the quartz sleeve bi-annually.

The sediment pre-filter that is prior to the UV filter will also need to be replaced on schedule.

PRO: Energy Efficient

The UV bulb doesn’t require much energy, and the wattage is similar to a normal lightbulb.

CON: Requires Electricity

Since the UV lamp needs electricity to work, if you have a power outage, your water won’t be disinfected.

CON: Pre-Treatment May May Be Needed

Unfortunately, UV light won’t be effective with water that has high hardness, turbidity, iron, and other impurities.

Every manufacturer of UV water sterilizers have their specifications for what the water chemistry must be like. At minimum, all manufacturers require a sediment pre-filter that has a minimum of 5-microns rating.

Read Also: What Are The Best Whole House Water Filters And Softener Combos?

New Whole House UV Water Filter Technology

Whole house UV water filters evolve over the years, and here are some of the latest improvements…

UV Sensors

Some UV water filters have sensors that detect a change in the UVT (ultraviolet transmittance) in the water. Basically, if something changes in your water or bulb that reduces the amount of UV light, the UV sensor will trip an alarm and may even cut off your water (through a solenoid valve).

Lamp Age

A lot of UV water filters have a display that will tell you the estimated age of your UV lamp or when it will need to be replaced. And when it gets to the end, it may even trigger an alarm signaling that you need to replace the UV bulb.

Safety Caps

There are UV light filters that have special safety caps on top of the UV filter to prevent children from touching the electrical components.

Read Also: How Does A Whole House Water Filter Work?

Final Thoughts

Whole house UV water filters can be great devices to keep your well water safe, and as an additional safety against contaminated city water. These UV filtration systems can destroy up to 99.9% of harmful pathogens.

It is important to size it correctly for your home, but to also make sure that your water chemistry is within the specs of the manufacturer.

If your home’s water has high turbidity, iron, or other impurities — it can decrease the effectiveness of the UV filter. Most manufacturers also require a sediment pre-filter that is rated at 5-microns minimum.

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Arie Van Tuijl

Arie Van Tuijl

I am a licensed home inspector in two U.S. states and the founder of Home Inspector Secrets. After performing hundreds of inspections, and seeing thousands of house defects, I realized people would love to have an online resource dedicated to home maintenance. I write detailed home guides and product reviews sprinkled with inspection tips. You can read my bio here.

About Home Inspector Secrets

Home Inspector Secrets is an online resource for owners, buyers, and sellers to understand all aspects of home maintenance. We have detailed home guides, product reviews, inspection advice, and much more.

Other Home Guides

Looking to learn more about home maintenance? Check out our other informative home product reviews and guides!