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Thinking about installing a Combimate?

See our FAQS below

What is the advantage of Combimate compared to other water treatment systems?

  • Combimate is a widely recognised, proven hard water scale inhibitor that since its launch in 1987 has delivered protection to hundreds of thousands of UK homes.
  • Combimate does not use magnets or any electricity in its anti limescale operation and is both easy to install with minimal maintenance.
  • The product is also supported by a professional customer service team with first class technical and spares support.

Do I need a separate (non-treated) drinking supply?

No. Combimate is not a water softener; water softeners generally use salts so softened water requires a separate supply because of the increased salt content.

What is Combiphos?

Combiphos is the name of the crystals used inside the Combimate unit. The Combiphos in your Combimate is a harmless food-grade polyphosphate compound which is used to prevent the formation of scale deposits in your hot water system.

What do the Combiphos crystals do to the water?

Combiphos which, when in contact with water is released in very small quantities, is sufficient to keep the mineral ions in suspension.

This action prevents the formation of scale while retaining the health benefits of the natural minerals contained in hard water.

Is Combiphos safe?

Yes. Combiphos is classed as a ‘food grade’ additive which conforms to European Standards EN1208 and World Health Organisation standards as a safe additive to drinking water.

You can install a Combimate directly on the rising cold water mains and safely bathe in or drink the water supplied. Combiphos is safe for water in contact with babies, tropical fish, pets and skin conditions.

Can I taste it?

No. Combiphos is completely tasteless.

Does it smell?

No. The Combiphos is odourless.

Will it discolour my clothes?

No. Combiphos has no effect at all on fabrics.

Will Combimate protect my central heating system?

In a central heating system, Combimate will only protect the boiler via the mains water feed into the heat exchanger. However, the ‘closed loop’ of the heating system (radiators, pipework etc) is not protected.

Combiphos coats the inside of the pipework, boiler heat exchanger and appliances with a non-residual, microscopic, protective coating to prevent scale-causing minerals from accumulating and aggressive soft water from corroding the system and appliances.

How do I know when the Combiphos crystals need replacing?

Combiphos will reduce in effectiveness in proportion to the amount of water passing through the Combimate unit. This will vary depending on individual consumption, so not every situation will be the same – hence, we recommend the Combiphos is replaced annually.

Does Combimate need maintenance?

Apart from the annual replacement of the Combiphos crystals, Combimate requires no other maintenance.

Does heat affect the Combimate?

Yes. If the Combimate is located in a warm environment (e.g an airing cupboard) or near a heat source, the Combiphos crystals will dissolve at a faster rate.

Ideally Combimate should be installed at room temperature with a cold water supply, located at least 450mm from any appliance or local heat source to prevent water in the dome from warming and accelerating the dissolution of the Combiphos.

My property may not always be occupied during the year. There could be times when the water is not used often or periods of non use. Would this affect a Combimate?

If the property where the Combimate is installed is likely to be empty for extended periods, we recommend the Combimate be emptied of Combiphos, and then Combiphos be dried and stored in a dry cool place.

If the Combiphos is immersed in water for more than three weeks without regular water through-flow, it will start to deteriorate and eventually breakdown.

Can I replace the Combiphos crystals myself?

Yes. Replacing the Combiphos is easy if the procedure is correctly followed. See ‘How do I change the combiphos crystals?’ question below or refer to the owner’s manual supplied with the Combimate unit.

Do I need a plumber to fit the Combimate unit?

Fitting the combimate requires a basic competency level of plumbing skills and equipment. However, for peace of mind we recommend a professional plumber installs the product.

Where can I buy a Combimate and the replacement Combiphos refills?

Both the Combimate unit and the Combiphos crystals can be purchased from plumbers merchants. Alternatively you can purchase online, click here.

Buy Online

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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