Distributing and recirculating pre-purified water centrally


The CENTRA-RDS is a storage and recirculating distribution system designed to work with other CENTRA or PURELAB systems or existing purification installations. In addition to storing and distributing pure water, the CENTRA-RDS maintains and improves water purity.

The CENTRA RDS stores, controls and distributes pre-purified water throughout a building, or a suite of laboratories, via a loop system.

  • Delivers up to 30 liters per minute of type I, type II and type III water from a distribution loop
  • Up to 18.2 MΩ.cm, type I, type II and type III water suitable for general and analytical applications
  • Bacterial specification <5 CFU/ml is maintained using a combination of technologies
  • Reliable continual supply of pure water using unique access controls and leak detection system with optional building management system (BMS) connectivity
  • Designed to operate with other ELGA LabWater systems or existing purification installations
  • Compact design provides more flexibility for new buildings and refurbishments.
  • Full service and validation support


Frequently Asked Questions (FAQs)

What is the CENTRA Product range?

The CENTRA is ELGA's centralised distribution system for laboratories to feed multiple polishers. 

What is the CENTRA RDS?

The CENTRA RDS is a purification system designed to feed a whole building from a plant room. It type 1 ultra pure water or simply distributes RO quality feed water. The difference between a CENTRA RDS and a CENTRA R200 is it does not have an RO so water supply is only limited by pre-purified volumes being distributed to it. Its 200m loop can cover multiple floors or multiple laboratories on a single floor to provide a truly centralised solution. The CENTRA saves space in comparison to competitive products by having an integral 350L reservoir to significantly reduce its footprint.

Most water purifications systems have a limited make up rate. Is this the case for the CENTRA RDS?

No, the RDS is designed as a distribution system for pre-purified water. This means the only limitation is the amount of water you are able to feed into the RDS.

How does the CENTRA R200 get type 1 water?

The CENTRA uses an SDI cylinder with a mixed bed resin to remove Ionic content and produce type 1 water.

Dispense flowrate 18 l/min
Inorganics (resistivity at 25°C) Up to 18.2MΩ-cm * Up to 18.2 MΩ.cm *
Bacteria <5 CFU/ml ** <5 CFU/ml **
Particles 0.2 μm filtration 0.2 μm filtration
Delivery flow rate 30 l/min

* Ion-exchange cylinder (SDI) installed

** Dependent on feedwater quality and the system is correctly installed and regularly sanitized 

Composite Vent Filter
Composite Vent Filter
Part Number
Life expectancy
12 months
Impurities Removed
Impact of Overuse

Increase in airborne contaminants and potential recontamination of purified water

Reverse Osmosis
Reverse Osmosis Module
Part Number
Life expectancy
24-36 months
Impact of Overuse

High levels of organics and inorganics remain in the water reducing the functional life of the DI pack

Ultra-micron filter
Ultra-micron filter
Part Number
Life expectancy
14 months
Impact of Overuse

Reduced flow-rates and bacterial specification will not be maintained

Pre-treatment pack render image
Part Number
Life expectancy
6 months
Impact of Overuse

Chlorine, chloramine and organics remain, increasing the burden on downstream consumables which will need more frequent and expensive changes

UV Light render image
UV Light
Part Number
Life expectancy
12-18 months
Impact of Overuse

Uncontrolled bacterial contamination and TOC levels are not reduced

To learn more about the benefits of the CENTRA Range or any other ELGA product, contact us and we’ll put you in touch with one of our Approved Partners and Lab Water Specialists.

Why Choose ELGA?

  • We have installed thousands of water purification systems globally, and our service engineers will apply their expertise to the installation, validation, and maintenance of your system
  • ELGA is trusted by labs around the World and we are renowned for excellent quality and reliability
  • Our dedicated local help desk is always available to provide advice, troubleshooting, and parts identification