2- The Ionisation Chamber Cell:
The Ionic chamber cells are composed of PVC, CPVC or stainless steel. They have sacrificial metallic electrodes embedded into them. These electrodes come in contact with the water to deliver ionic metal particles within the closed water network system. The overall mass and surface contact of each electrode varies based on the manufacturers’ design specifications in relation to water volumes. When multiple chamber cells are required, they are installed in parallel or in series and with one or multiple power output control units.

2.1 - The Electrodes: The sacrificial electrodes for CWN systems have a mass that vary between 250g and 2.5 Kg with a surface contact of between 6cm2 and 200cm2. These biocide electrodes are composed of Copper (Cu) and/or Silver (Ag) alloys at different concentrations. % Cu/Ag = (99.9/0 | 90/10 | 80/20 | 70/30 | 30/70 | 0/99.99). The alloy concentration levels will vary based on the manufacturers specifications.

2.2 - Specifics: Some manufactures might also use two dissimilar metal alloys to accomplish metallic water ionisation when electrode polarity reversal is not offered. Ionisation is accomplished with a typical small sacrificial biocide electrode on one side and a “non-sacrificial” draw electrode on the other. Some might use a negatively charged metallic chamber cell instead of a draw electrode. These non-sacrificial electrodes are normally composed of titanium, zinc, stainless steel or even in some cases, platinum alloys.

System Maintenance: These types of units normally have easy access to the ionic chamber cell and let the user periodically inspect and clean the electrodes without the need for mechanical tools.

System Requirements: Periodic shocking with the appropriate agent (preferably non chlorine based) is required to “burn” away any remaining organic matter left behind by the biocide effects of copper silver ionisation.

Prices: These CWN systems have a price range of between $200 and $2,500 (US) depending on overall electrode mass and power output. Remember, the more water you have to treat, the bigger size unit you will require.

Conclusion: The size and number of CWNs required for each installation depends on the total water volume found in the swimming pool or body of water (ornamental fountain, small pond, mammal aquarium).

The CWNs are small in size with relatively small electrodes and deliver a fix VDC power output. Unless the manufacturer uses a non-sacrificial electrode, the manufacturer should offer a power output polarity switching feature for the even ionisation of electrodes. In all, these systems are small in size and have a relatively simple electronic power converter system; this is why these systems are readily affordable and commonly used in swimming pools, spas and ornamental fountains.

Important note: Since these units have a relatively small electrode mass / surface contact and a low VDC “fix” power output capacity, they are not manufactured for open loop systems even if the silver concentration is modified. It is strongly advised not to use these systems in open water network systems (i.e. domestic hot water, cooling towers, irrigation). Closed loop water systems use small amounts of makeup water on a daily basis. As a result, these smaller ionisation systems for closed water networks are ideal to deliver and maintain appropriate ionic levels.