SYSTEM COMPONENTS

THE ELECTRODES

Application of a direct current with a potential difference of 1.23 V generates two side effects: heating and electrolysis. The heating phenomenon is totally negligible when applying the principle of electroosmosis on walls since the applied potential differences are minimal compared to the wall mass.

The electrolysis phenomenon, instead, will inevitably lead to corrosion of the positive electrode if suitable prevention meaures are not taken. There are two options: using potential differences lower than 1.23 V or using positive electrodes made up of materials that ensure their electro-chemical stability even with higher potential differences. In the first case, the potential difference is too low to ensure that the natural electric field is actually inverted, thus not being able to force the movement of the water inside the wall back to the soil, but only being able to slow its rise.

This is the reason why ELO has decided to use electrodes suitably protected against corrosion. ELO SYSTEM positive electrodes have been specifically developed and manufactured for applying this technique. They are made up of a metallic material activated by a special mix of noble metals, thus ensuring optimum mechanical properties, great flexibility, total electro-chemical stability and minimum invasiveness owing to their tiny diameter (1.5 mm). Conduction between the electrode and the wall is also ensured by specific additives that make the mortar used for fixing the electrodes inside the wall more conductive.

THE CONTROL UNIT

The ELO SYSTEM is powered by ELO UNIT, an automatic management electronic control unit. This control unit is connected to the power supply mains and delivers very low voltage current (approx. 4-6 Vdc) to the electrodes.

The delivered amperage is also minimum and decreases while the wall dries. Although the system is constantly powered, consumption is minimum.

The control unit can also record the delivered amperage on a daily basis, thus monitoring the dehumidifi cation process and signaling any anomalies.

Thanks to its small size, it can be positioned everywhere.

THE SALT REAGENTS

Salt reagents are generally applied when installing the system to additionally protect walls and plasters.

Despite salts, which have oxidating features, do not represent a problem for the “life” of the electrodes thanks to the mechanical and physical characteristics of their components, their presence may potentially cause wall damage and deterioration.

In fact, their high volume variation when switching from the amorphous to the crystal phase exerts enormous pressure on the capillaries. This pressure can damage walls and, in the worst cases, make their materials crumble. Also, whereas the water that has reached the wall surface evaporates, salts remain on the surface, so their concentration increases progressively exactly where they can provoke the highest damage.

Walls can therefore be restored properly only if dehumidification is combined with thorough desalination.

ELO solves the problem of the presence of salts in walls by applying ELO-Dry, a specific salt reagent capable of penetrating a few millimetres inside walls, thus neutralizing hygroscopic salts that could be activated by the atmospheric water. Bear in mind that the salts inside the wall structure are no longer dangerous since the electro-osmotic system eliminates the water inside the walls.

ELO-Dry should be applied, if possible, after the walls have been dried by the electro-osmotic system (after a few weeks of operation) with two coats of low-pressure spray coating.