How To Replace a Cartridge in a Mixer Tap

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How to Replace A Mixer Cartridge

How to Replace a Cartridge in a Mixer Tap

One of the most common leak-related enquiries we receive is about replacing a mixer tap cartridge. This component controls the water’s flow and temperature and is typically located inside the handle or body of the tap. This component includes a mechanism that enables you to mix hot and cold water to achieve the right temperature. Mixer tap leaks can occur when the cartridge is worn, damaged, or develops seal cracks or tears.

If this has happened to you and you now want to know how to replace a cartridge in a mixer tap, read on! Here we outline some easy mixer cartridge replacement steps and give you plenty of additional information so you have a thorough understanding of the topic.

Shop all mixer tap cartridges here

How do you know what kind of mixer tap cartridge you need?

Firstly, measure the diameter of your existing cartridge. The two main sizes for cartridges are 35mm and 40mm, but newer, slimline taps could also have 25mm mixer cartridges.

Next, have a look at your existing tap mixer cartridge, is it flat or raised?

Image of the side profile of two types of mixer tap cartridges: flat and raised.

Now, have a look at the bottom of your cartridge. Flat and raised cartridges for mixer taps have different profiles.

Image of flat and raised tap mixer cartridge bottoms

These examples suit most popular brands of mixers including Brewers, Irwell, Greens, Raymor and many more.

If your end looks considerably different, you may need a special mixer tap cartridge replacement made by the manufacturer of your mixer. If in doubt, take your existing cartridge to your local hardware or plumbing store and request installation by a registered plumber. This professional can also source the correct parts for you. Our plumbing directory can put you in touch with the local plumbers in your area.


How does a mixer tap cartridge work?

The answer depends on the type of mixer cartridges involved. Typically, you will have inlet ports for hot and cold water – these are connected to hot and cold water supply pipes under the sink. A valve stem sits within the tap mixer cartridge and features passages aligning with the inlet ports. A sealing mechanism covers the inlet ports. When the stem is closed, water flow is blocked. The water mixing action occurs as the stem is adjusted and you allow more or less hot or cold water.

How to install mixer tap cartridges

The taxonomy of a mixer tap and the location of all its components, including the mixer cartridge

  • Turn off water at mains
  • Remove handle by removing indicator button
  • Use an Allen key to unscrew the grub screw
  • Unscrew dome cover and locking nut
  • Install the mixer tap replacement cartridge
  • Re-assemble tap
  • Turn on water supply and inspect for leaks

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