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Water: the hidden damage

Softwater corrosion

It can be a surprise to learn that naturally occurring softwater can be harmful to your water system.

Natural softwater is water that contains very little natural minerals and this ‘pure’ water is actually aggressive to metals and causes corrosion. The symptoms of such corrosion can be when the residue (caused by oxidisation of the metal pipes) comes out of your taps, turning tap water brown. Left unchecked, such continual corrosion will cause pinholes in the pipe and leaks may be the result.

How can softwater cause corrosion?

Natural softwater (sourced from lakes, rivers etc) is often low in pH (a term used to describe a scale of acid / alkalinity) making it slightly acidic. This acidity makes the water corrosive to metals.

Hardwater can still be acidic, but certain minerals in the water have properties that prevent the chemical reaction of corrosion taking place – thus providing a level of protection for the metal. The drawback is that such minerals can also build up as limescale.

Domestic water softeners

These devices have been widely accepted as a solution to combat the effects of limescale by removing minerals in the hardwater supply. 

Water softeners employ differing methods of operation (depending on model) , but there is a long-running debate to whether hardwater that has been artificially softened is corrosive to heating systems or not.

Domestic Water Softeners also come with their own pros and cons – click here for more information.

Combimate beats both limescale and softwater corrosion

Combimate is not a water softener but a phosphate dosing device.  Combimate does not alter the hardness (or softness) of the home's water supply but through the process of adding phosphate prevents limescale build up and provides softwater corrosion protection - click here to learn more

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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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