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See our FAQs below

The Combimate is due for its annual re-fill, but there is still plenty of Combiphos crystals in it. Do I still need to change the Combiphos?

Yes. To maintain the treatment effectively both the quantity and quality of the crystals needs to be kept at an appropriate level.

Combiphos reduces in volume in proportion to the amount of water passing through the Combimate which will vary according to individual circumstances.

Combiphos immersed in static water for more than two months without through-flow will start to deteriorate and will eventually form into a solid mass.

We recommend replacing the Combiphos annually. This provides a simple routine for a range of typical domestic applications.

I have a Combimate fitted but still have scale in my showerhead / kettle / taps.

Combimate is not a water softener. Combiphos reduces the scale deposits by keeping the minerals which cause scale in a dissolved and suspended state at higher temperatures. As a result most scale-causing minerals pass through the system instead of forming scale deposits.

Unlike softened water, water that passes through a Combimate remains unchanged, so hard water treated with Combiphos but left in a kettle may still create a build-up when the water evaporates. However, this residue is more paste-like in consistency rather than hard scale and is easily wiped away with a cloth without need for chemicals.

How do I change the Combiphos crystals?

To remove the old Combiphos remove the cover from the Combimate (this automatically isolates the water supply) then open the unit by removing the cover, filler plug, retaining ring and clear dome.

Remove old Combiphos. Reassemble in reverse order but place new combiphos through the top prior to replacing the round plug. Clean the ‘o’ ring seat before replacing the ‘o’ring with new (supplied within the replacement Combiphos jar). Click here to read our full maintenance guide.

Do I need to turn off the water supply to change the Combiphos?

No. When the Combimate cover is removed the mains supply is automatically isolated. This feature also works as an emergency mains-supply cut-off device - much quicker and easier than trying to find your stop-cock !

I want to change the Combiphos but can’t undo the metal ring?

Having removed the cover you should then remove the red filler plug to relieve the internal pressure. The aluminium ring should be not more than hand tight, although after 12 months it can very occasionally ‘bind’ on the plastic thread. If it will not release using both hands we recommend using a filter band or ‘boa-constrictor’ type tool available at DIY outlets. When replacing the ring it should only tightened manually.

I have just changed the Combiphos and have a leak !

The most likely cause is that the large ‘O’ ring is in the wrong position or a small piece of Combiphos is preventing the ‘O’ ring from seating correctly. (See changing the Combiphos – above).

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From just £171.60 (inc VAT)

Combimate will last a lifetime and is virtually maintenance free.

£27.50Inc VAT
Combiphos refills

To maintain your Combimate’s effectiveness, we recommend Combiphos is replaced annually.


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