Selection of elector devices for electrochemical heating water conditioning

The use of an elector-corrosion-protection device for prevention of corrosion in heating system or for the refurbishment of old silted heating systems is always part of an overall package. Therefore, prior the selection of an elector-corrosion-protection device a water analysis should always be accomplished.

The analysis of the heating water provides fundamental information for the determination of what actions should be made in addition to the electrochemical water treatment. This may include system flushing with the cleaning and dispersing agent OXILIN-P20 or demineralisation of make-up water.

The selection of the correct elector-corrosion-protection device depends on the system volume without considering the contents of buffers. For simplification the system volume can approximately be estimated by the heating output.

As an average value <20 l/kW is considered. For a more detailed interpretation the following values can be used:

  • ~18.5 l/kW UFH
  • ~12 l/kW Radiators
  • ~8,5 l/kW plate heaters

These values are based on old boilers. Modern heating technology requires about 10-20% less power at the same system volume, which should be taken into account in the calculation.

TypeSystem volume m3 max.Installation
elector XS5 0.5Full flow
elector S10-V1.5
elector S10-B 1.5Bypass
elector M25 5.0
elector L60 10.0
elector XL13030.0
elector XL+30080
elector XL+500150
elector XL+800250
elector XL+1000


If the system consists of both underfloor and radiators the elector is always choosen over the values for underfloor heating. In marginal cases you should always select the next larger device. Due to constantly developing heating technology, the system volume of new systems differs at the same heating output in comparison to older plants. The table is to be understood only as an auxiliary tool and is based on the system volume and heating output of older heating systems.

In case of large heating systems the total heating power should be divided onto a number of elector-devices to be installed at different locations in the system. E.g. in the main heating central an elector XL130 and in each connected houses one elector S10.

There are two types of the elector S10. The elector S10-B and the elector S10-V. The difference between the devices is in the first line the integration into the system. The elector S10-V is installed in full flow (flow or return). The elector S10-B is installed into a bypass. Due to the different installation situations there is a difference in the functional detail.

The elector S10-B is, as well as the devices for corrosion protection in heating systems up to 10 MW, installed in a bypass with regulated flow rate. The result is an quiet zone in the elector where suspended solid can settle. Due to the longer residue time of the water in the elector the electrochemical water treatment is much more intensive - especially in the electrochemical oxygen consumption the factor time plays a major role. The elector S10-B is the "refurbishment unit" and should be used especially in older systems, as for example in UFH heating systems with non-diffusion-proof plastic pipes.

The elector S10-V is for installation in full-flow an should be installed in newer system, when the stabilisation of the pH is the first purpose.


Situationelector S10 - full flowelector s10 - bypass
1New system with radiator, underfloor heating, heat pumps, heat exchangers etc.
2Old system with severe sludge problems
3like 2, including system flushing with OXILIN-P20 and installation of an air-separator
4Old system with non-diffusion-protected underfloor heating and air-separator
5Old system with heat exchanger, including system flushing with OXILIN-P20
6like 5, without additional flushing but with installation of a dirt separator in the return