Guldager – Wise Water Treatment

Guldager A/S is a Danish company founded in 1946 by Mr Alfred Guldager. Today the company is run by his two grandsons Hans & Henrik Guldager.
The Guldager group employs approx.. 90 people divided between the headquarter in Denmark, subsidiaries in Belgium and Switzerland and sales office in Berlin..

Throughout the years, the business areas have expanded in more directions from protection against corrosion and bacteria to desalination and softening of water.

Today, Guldager offers all kinds of water treatment for drinking water, boiler water and industrial water. To ensure and maintain the performance of our solutions, we provide a full portfolio of services. Our worldwide service includes spare parts availability, maintenance, repair and modernization. This approach enables us to guarantee the quality and value of your system.



Guldager – our history…

Since 1923, when Alfred Guldager invented the Guldager Electrolysis system for prevention against corrosion and scale, our business has been water treatment.
Over the years we have achieved a profound knowledge on this sector, which as a result includes the development of further products for water treatment.

Apart from the latest generation of the Guldager system, the Katolysis, the product range today also spreads from small softening systems to high tech RO-systems which are used for desalination of seawater, as well as antifouling systems for the oil industry.
We know, that it is wise to learn from nature and adapt her conformity to our development and production. Consequently all our products must fulfil three basic demands:
•They must work efficiently
•Achieved results must be reproductible
•They must be safe for the environment

Business areas

Corrosion Protection
Katolysis for domestic water piping systems
CatoCool®, complete water treatment programme for cooling towers and industry
Cathodic protection of swimming pool filters, tanks etc.
Scale and lime stone protection
CalcFree, Carbon dioxide dosing for domestic water and industry
UniSoft and UniRo
Softening, de-carbonisation, and reverse osmosis for:
Hotels, restaurants and catering
Laundries and industry
Desalination of seawater
Membrane filtration of sewage


Guldager is a Danish family owned company. The company was founded in 1946 and is today a modern company, represented internationally through subsidiaries, agents and dealers. We apply decades of experience, up-to-date knowhow and cutting-edge technology to meet the many needs of our customers.


Guldager A/S is an international company committed to its customers. We are used to provide service and support to our customers all over the world. Please feel free to contact any member of the Guldager team, we are looking forward to hearing from you.

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Copyright Guldager A/S 2013
GULDAGER A/S HEJREVANG 1-5 DK-3450 ALLERØD +45 48 13 44 00