Changing your Water Filter Cartridge in 10 Easy Steps
It's easy to change your water filter cartridge.
Follow these 10 easy steps.
Key Points
- Changing a filter cartridge is a straightforward job you can do yourself in 10 steps, with no need to call a plumber.
- Always turn off the water supply and release the pressure at the tap before undoing the housing bowl.
- Check the condition of the black O-ring and replace it every 2 to 3 years, greasing it lightly with silicon grease if it's dry.
- When reassembling, screw the housing bowl on by hand only - never use the spanner to tighten it, only to loosen it.
- Once refilled and leak-free, run the tap for 5 minutes to flush out any manufacturing debris before use.
Table of contents
How to Change Your Water Filter Cartridge in 10 Steps
- Turn off the water supply to the filter system and open the filter tap to release the pressure.
- Place the spanner that came with your kit around the body of the filter bowl and slide up until the lugs enable you to unscrew the bowl from the housing cap. Rotate from right to left looking straight on, or clockwise if you view it from above. If you haven't mounted the housing to the cupboard wall you may need to brace the cap somehow.
- The housing bowl will be full of water so proceed carefully to minimise spillage. Once unscrewed lower the housing bowl away from the cap, and remove to the sink.
- Empty the water and remove the old filter cartridge.
- Rinse and wipe out the housing bowl.
- If the black O ring is 2 to 3 years old this is the time to replace it. Otherwise ensure the O ring is in good condition, it's worth coating it silicon grease if it's a bit dry. Replace it in the groove, ensuring the O ring is properly seated.
- Unwrap the new filter cartridge and place inside the housing bowl, making sure it slips onto the small stand pipe in the base of the housing bowl.
- Screw the housing bowl onto the cap, turning anticlockwise until hand tight - do not over tighten.
- Turn on the water supply and allow the filter system to refill - once done close the tap and check the housing bowl to cap for leaks. If there are any leaks then use the spanner to tighten the bowl a fraction. You may need to either turn off the water supply and release the pressure again to do this.
- Finally, once you're certain there are no leaks, open the tap and allow the water to run for 5 minutes to flush out any manufacturing debris.
DO NOT use the spanner to tighten the housing bowl - this will make it very difficult to undo at the next filter change.
FAQs
Do I need to turn off the water supply before changing the cartridge? Yes - turn off the water supply and open the filter tap to release the pressure before you start undoing the housing bowl.
How often should I replace the O-ring? If the black O-ring is 2 to 3 years old it's worth replacing it while you're changing the cartridge - otherwise just check it's in good condition and grease it lightly if it's looking dry.
Can I use the spanner to tighten the housing bowl when refitting it? No - only screw it on by hand until hand tight. Only use the spanner to help loosen it at the next change; using it to tighten can make the bowl very difficult to undo later.
Why should I run the tap for 5 minutes after fitting a new cartridge? This flushes out any manufacturing debris from the new cartridge before you start using the filtered water.
About the author
Louise Allen is a partner at Fountain Filters, where she's helped run the business since 2011. Alongside the day-to-day order management, despatch, and quality, she's built up a practical, hands-on knowledge of water filtration, and reviews the site's articles to keep the advice accurate and genuinely useful. Outside work, she's run the London Marathon with business partner Simon.
