Closed water systems

Water treatment services and chemicals

Closed circuit systems are subject to corrosion, scaling, sludge formation and bio-fouling all of which can result in problems such as system lack of performance, reduced economy and increased maintenance and repair costs. It is important to choose the correct treatment to suit system conditions which can depend on a number of aspects such as system type, eg chilled, LPHW, MPHW, HPHW and materials to be protected; copper, brass, aluminium, iron, mild steel, stainless steel etc.

•   Improve the performance and economy of your systems

•   Decrease maintenance and repair costs and prolong the life of systems

•   Benefit from application-specific chemistry and engineered solutions

Corrosion inhibitors

We have a wide range of corrosion inhibitors specifically designed for various types of closed water systems. We understand that closed water systems come in a variety of sizes and applications. Because of this we strive to provide the most comprehensive range of corrosion inhibitors possible, from multifunctional borate nitrate based products, to control corrosion in closed cooling systems, to non-toxic corrosion inhibitors for use in small multi metal heating systems.


Microbiological fouling can lead to multiple problems within closed water systems. Therefore using the right biocide to protect your system against these problems is vital. SUEZ have a fantastic range of biocides that are proven to eliminate microbiological contaminants found within closed water systems. Whether you need a biocide for day-to-day protection or to quickly eliminate a problem that has arisen in your system, we have the chemicals that are proven to do the job.



The build-up of scale can lead to severe problems within closed water systems as it will dramatically reduce the ability of a closed water system to transfer heat to and from water. Therefore the application of an effective chemical scale protection regime is an essential aspect of maintaining your closed water system. SUEZ have a wide range of anti-scale chemicals to protect your closed water system from the problems cause by scale build up; to see the full list please visit our closed water system chemical range page. Plant and equipment is also an effective scale control method.


Water freezing within a closed water system can be a major problem that could potentially damage your system beyond repair. Protecting it against freezing temperatures using Glycol and other antifreeze chemicals is an economical way to protect yourself from the major problems that frozen water in closed systems can cause, such as burst pipes, plant failure, loss of services and production and remedial reparation works, all of which can have major cost implications. SUEZ have a range of chemicals that can be used to protect against a frozen system and our full range of antifreeze chemicals please visit our closed water system chemical range page.


Closed water systems generally have a fixed volume and a build-up of foam from the use of certain chemicals can dramatically increase the volume contained within the system, putting extra unwanted pressure on the system. Alternatively a situation may require the use of chemicals prone to foaming, such as when higher concentrations of chemical are required for systems which may be stood dormant and unused for extended periods, or biocidal flushes. In this instance an antifoam chemical is required alongside the chemical which may be prone to foam, to ensure a build-up of foam doesn’t occur.


The pre-commission cleaning of new or refurbished closed water systems before they are put into operation is vital to ensure that problems don’t arise due to contaminants left behind from the manufacturing process. Manufacturing contaminants can lead to blockages, corrosion, scale and microbiological hazards from the beginning of the systems operation, which can dramatically reduce the overall lifespan of the system. SUEZ not only have a wide range of highly effective pre-commission cleaning and flushing chemicals that are extremely effective at removing unwanted contaminants from your system, we also have an expertly trained team who specialise in this process


Closed water system chemicals are ideally dosed automatically via a precise chemical pump, giving the correct amount of chemical for the application. One such popular method for closed systems is to link the chemical pump to a water meter that is measuring the make-up water quantity so that chemical is replenished as water is added. However some systems will have a very low make up but, as inhibitor levels may fall over time, it is essential to carry out periodic chemical tests to ensure that the correct inhibitor levels are maintained.

what our customers say:

I feel that B & V (SUEZ) are an extremely professional and reliable company, in the way that they approach and support our water treatment requirements. They offer a wide range of services and have always met our expectations.

We offer one of the largest ranges of products, custom engineered systems, chemicals, training and support services available from a single source.

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