How often should I change my filters?

Premium water filters can make a shocking difference to the quality of your water. They remove tastes and smells caused by unwanted chemicals and contaminants, bring certainty and peace of mind through the flood of water contamination headlines, and provide benefits for your health, home, and wallet. However, this all hinges on the condition of your filter cartridges.

Water filters work by capturing impurities and storing them in a filtration medium. Different media have different storage capacities, but any water filter will need to be replaced eventually to avoid having its captured contaminants leach back into your water supply.

This article takes a look at some of the different filters on offer, things that can influence their lifespans, and how often you should be changing your filters.

Why do I need to change my filters?

Whatever filtration medium your filter system uses, it will have a limited capacity. Sediment filters can grow clogged with silt and rust, carbon granules can completely fill all their cracks and pores with impurities, ion exchange resins can run out of ions to exchange, and RO membranes are gradually worn down by the high pressure of their filtration process.

Filters that have exhausted their capacity have several impacts on your home and water:

• Reduced Performance: Filters nearing their maximum capacity will have a diminished impact on your water quality. If you have an ion exchange cartridge that has expelled most of the sodium in its resin, you may start to notice an increase in limescale around your home from more calcium and magnesium slipping through the softener.
• Leaching Contaminants: Once a filter has filled all its pores or cracks with contaminants, it is unable to pull any more out of the water. Instead, it may start to do the opposite; as water flows over the exhausted filter, it may pull collected contaminants back into the stream and carry them into your home.
• Bacterial Growth & Biofilms: Over long periods of time, the accumulated impurities in filter cartridges provide a breeding ground for bacteria. Even if your filters haven’t completely exhausted their filtration capacity, leaving them longer than 12 months can lead to bacterial concerns—especially in later filtration stages after disinfectants like chlorine have been removed.
• Lowered Water Pressure: Filters clogged with sediments and impurities won’t be able to filter water as quickly, as the pores will get tighter and restrict flow rates.
  

It is also worth noting that most water filtration systems will have warranties that require regular filter changes. Complete Home Filtration, for example, recommends filter replacements at least every 12 months to avoid these issues and keep the system’s warranty intact.

How contaminants build up in water filters

Different kinds of filters have their own ways of pulling impurities out of your water. The method of filtration will significantly impact the lifespan of your filters.

Sediment Filters

Filters designed to capture physical particles like sand, silt, and rust are the simplest variety of water filters. Modern sediment filters are often made from water-safe plastics like polypropylene, but historically, they have also been made from finely woven cloth or even carefully washed sand. Complete Home Filtration’s sediment filters can catch particles as small as 1 micron – 70 times smaller than the width of a human hair!

Carbon Filters

Charcoal and activated carbon filters are among the most common filtration media used today for water and air purification. Specially treated carbon granules (granular activated carbon, or GAC) have tiny crevices that can capture impurities through a process called adsorption.

GAC filters are highly effective for filtering common impurities like chlorine and its carcinogenic disinfection by-products. Some filters use specially treated catalytic carbon to enhance its reactive properties, making it more effective for breaking down stable particles like chloramine.

Ion Exchange Filters

Rather than presenting a physical barrier for contaminants like carbon and sediment filters, ion exchange resins use the positive or negative charge of certain particles to draw them out of the water and replace them with something else. Softening resins draw in hard water minerals like calcium and magnesium, replacing them with harmless sodium to reduce limescale.

Reverse Osmosis Filters

RO purification involves using high pressure to force water through a semi-permeable membrane, capturing impurities as small as 0.0005 microns. This method of purification catches chemicals too fine and/or stable for other filters, stripping out things like fluoride and pharmaceuticals to make your water as pure as possible.

Ultraviolet Treatments

Ultraviolet (UV) light is a powerful disinfectant used to kill bacteria and sterilise water supplies. The light neutralises bacteria without changing the properties of the water itself, making it a much subtler treatment method than chemicals like chlorine.

However, UV treatments must be paired with physical filters to provide complete protection. The light neutralises bacteria, but any sediments, chemicals, or organic matter in the water will be unaffected.

How long do whole-home water filters last?

The exact lifespan of your filters will depend on the size, type, and configuration of your filtration system, the amount of water passing through them, and the quality of that water.

Each Complete Home Filtration customer has an individual filter replacement schedule tailored to their specific home and water. However, there are some general guidelines that help predict how often your filters will need changing.

• Sediment Filters: For most homes, 9-12 months. Larger filters have higher capacities, providing longer filter cycles for homes with high sediment levels or large families that use a lot of water. In extreme cases, these filters may need changing every 6 months.
• GAC Filters: Activated carbon cartridges are usually changed at the same time as sediment filters unless the sediment levels present in the water are abnormally high.
• Ion Exchange Resin: The lifespan of a softening filter will vary depending on your region’s water hardness. A Melbourne townhouse may only need to change the resin cartridge every 12 months, while a large property in Adelaide may use up the softening resin in just 5-6 months. We have a custom replacement cycle called a Hard Water Pack (HWP) that provides a second softening filter with each replacement set, to be replaced halfway through the life of the other cartridges.
• Reverse Osmosis Filters: Depending on the quality of your water and what additional stages of filtration you have before your kitchen sink, an RO system will need its filters changed every 6-12 months. If you have a whole-home filter as well, the under-sink system’s filters will typically last longer. The RO membrane itself will also need to be replaced every 24 months.
• Ultraviolet Disinfection Systems: Unlike the physical filters, this cycle depends on the lifespan of the UV light bulb. Complete Home Filtration’s 56-watt bulbs are rated for 9,000 hours of disinfection (a little over a year).

How to know when your filters need changing

No matter what kind of filter your home uses, there will be early warning signs to let you know when the filters need to be replaced. These signs can either be subtle changes in your water quality or a built-in alert from the filter itself.

Signs your filters need changing include:

• Low water pressure: As a sediment filter becomes clogged with more particles and impurities, the space for water to pass through will be restricted. A noticeable drop in pressure can indicate a particle filter in need of replacement.
• Change in taste or smell: Carbon filters may not impact flow rate as they pull more impurities out of your water, but there are still signs when they are approaching maximum capacity. Once all the cracks and pores across the carbon granules are full, chemicals like chlorine will start slipping back into your water and impacting the flavour and odour from every tap.
• Limescale on kettles and shower heads: Scale forms faster in higher temperatures, so the first places hard water will start showing up will be outlets and appliances that regularly hold or dispense hot water. If you are noticing white mineral deposits that do not wipe away easily, your softening resin may be exhausted.
• Built-in alerts or reminders: Complete Home Filtration sends text and email reminders 30 days before your filters are due for replacement. In some cases, the taste, smell, and flow rate of your water may be completely fine at the end of a filter’s lifespan, but it is still important to change them on time to avoid bacterial issues.
  Additionally, if you have one of CHF’s rainwater systems, they have a built-in alarm that notifies you when the UV bulb has gone out.

Complete Home Filtration: One solution, one set of filters

Regular filter changes are a vital part of maintaining your home’s water quality. Complete Home Filtration makes filter changes easy, cutting out the hassle of individual tap and shower filters while still providing filtered, softened water to every outlet in your home.

Our regular filter change reminders help you stay on top of annual maintenance, and our 24/7 Australia-based service team is on hand to help with any questions or concerns you may have about your filters. We also have a filter subscription service, allowing customers to pay off their next set of filters before they’re due.

We also perform an in-depth water test and consultation as part of our quotation process, allowing us to tailor your filtration system and filter schedule to your specific home and water. To find out more or book your own FREE consultation, send us a message below or call 1300 693 459.