SoluCalc : frequently asked questions

Do you have questions about SoluCalc? We have the answers! 

Questions about the operation principle

The Belgian Building Research Institute – (BBRI, equivalent of CSTB in France) carried out a full-scale test on the various techniques used against limescale: salt softeners, CO2 and magnetic systems.

The conclusion of their report is as follows:

“Among devices tested, the CO2 injection device proved particularly effective, offering a result quite close to the softener set at 15°F”

Injecting CO2 into the water transforms limescale (calcium carbonate) into calcium bicarbonate.

It is a well-known chemical reaction that is guaranteed up to 95 degrees Celsius:


CaCO3 + CO2 + H2O → Ca (HCO3)2

Limescale is actually calcium carbonate in an annoying form because it sticks everywhere: on the resistances, on the shower screen…

Calcium bicarbonate is interesting because it is:

  • Soluble in water: it is therefore dissolved in water and goes away with the flow of water
  • Non-encrusting: it is no longer able to attach anywhere

In addition, bicarbonates are excellent for your health.


SoluCalc only injects CO2 to treat the limescale and get rid of its drawbacks.

It therefore does not use any salt and does not carry out regeneration.

The result: thousands of liters of water saved, and a healthier planet.

Résultat : des milliers de litres d’eau économisées pour vous et une planète qui se porte mieux.

No, the SoluCalc is designed to inject a small dose of CO2 needed to treat limescale without making your tap water sparkling.

It uses a dose of CO2 that is 10x smaller than that used for sparkling drinks.

Many clients immediately feel the difference on their hair, others even see their skin problems disappear (until the CO2 bottle is empty).

The taste of your water will not be altered since there are no added minerals in the water.

Unlike a conventional softener, SoluCalc does not remove limescale from the water.
The water hardness level is expressed in French degrees and represents the number of milligrams of calcium per liter of water.
With the action of SoluCalc, calcium carbonate is transformed into calcium bicarbonate.The amount of calcium therefore remains the same, but there is no longer any limescale in the water.


It is true that the injection of CO2 into the water has an impact on the pH of the water.

For over 10 years, SoluCalc has been specially designed to inject the smallest dose of CO2 in order to impact the pH of the water as little as possible.

SoluCalc lowers the pH by 0.5, so there is no risk for your installation.


Yes, since the CO2 used by SoluCalc is a food-grade gas, the same used to make sparkling drinks, and used in beer taps all around the world.

Questions about CO2

CO2 is an inert gas, which means it does not explode. The CO2 used by the SoluCalc is food-grade CO2. It is the same CO2 that is used to make sparkling water (Sodastream, etc.) and in cafes and restaurants for beer taps.

You just have to know that CO2 is a gas heavier than air, so it tends to fill rooms from below.
Assuming a 10 kg bottle of CO2 suddenly emptied into a sealed room at the very bottom of the building, the volume of CO2 would reach 4.5 m³ of CO2 in the air.
It would fill about 30 cm from the floor in a 15 m³ room, and those 30 cm would contain no oxygen.

You might want to avoid crawling next to the cylinder if such a situation was to arise.

It’s very simple: when the left pressure gauge drops to 0, it’s time to replace the bottle.

The average consumption is 10 kg of CO2 per 100 m³ of water.

A family of 4 will therefore have to replace the bottle once a year.


The average selling price of a 10 kg CO2 refill is 25 euros. This means that SoluCalc has a cost of around 5 euros per inhabitant per year.
You can also ask your installer to subscribe to a “Gas Comfort Service” which includes: delivery of a full cylinder, removal of the empty cylinder and verification of the settings and correct operation of the SoluCalc.

Food-grade CO2 can easily be found everywhere in Europe from various suppliers: Air Liquide, Westfalen, etc.
You can also order CO2 from us, and a 10 kg bottle will be delivered directly to your home.

Questions about the device

Unlike conventional softeners, SoluCalc does not require any maintenance.

SoluCalc has a 5 year warranty.


You can use this simulator which will allow you to define which device model is suitable for you.

Questions about installation and settings

By setting the SoluCalc to curative mode (+1 bar of pressure instead of +0.2) for a maximum of one month, a surplus of CO2 will be injected, more than the amount needed to treat the incoming water flow.

This excess CO2 will circulate in the installation and dissolve any limescale it encounters, thereby cleaning your installation.


The SoluCalc requires settings to be defined manually upon start-up: a pressure difference of 0.2 bar between the CO2 pressure and the dynamic pressure of the water.

When the kitchen tap is fully open, the CO2 pressure must be set 0.2 bar above the water pressure to give the CO2 enough force to be injected into the water.

The complete settings procedure can be found in the user manual.

The SoluCalc device is extremely easy to install.

You can:

  • arrange installation with a SoluCalc installer
  • have it installed by your plumber, which should take two hours
  • install it yourself