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You are here: Home1 / Water2 / Closed Loop Water Systems

Closed Loop & Closed Circuit Heating & Cooling

Closed loop and closed circuit water systems

Expert water treatment solutions for closed loop heating, cooling and chilled water systems.

Water Treatment Services is a leading independent UK water treatment company offering a full range of expert services for the management of closed systems, closed loop heating, cooling and closed circuit chilled water systems.

Our closed loop water treatment solutions address the problems of corrosion, fouling, biofouling and scaling that affect the reliability and performance of closed circuit and closed loop water systems.

Our specialist services for closed circuit water systems are delivered by in-field experts who combine the latest high performance closed loop water treatment techniques to help reduce costs, save energy, enhance operational efficiency and reliability, and extend asset lifecycles.

Expert closed system & closed loop water treatment solutions

Our specialist closed loop and closed circuit water treatment solutions include:

  • Closed Loop Water Treatment & Servicing

    In-field closed circuit and closed loop water treatment, engineering support and maintenance services to control corrosion, fouling, microbial fouling and scaling.

  • Monitoring & Validation

    Latest water analysis equipment to monitor and validate closed circuit water treatment programme performance.

  • Energy Efficiency

    Expert investigation and analysis to identify process improvement and energy efficiencies involving heating, cooling and chilled water systems, and heat transfer processes… energy efficiency →

Full national UK coverage

With offices in London serving the South and South East England, Manchester (North West), Birmingham (Midlands), Bristol (South East England and Wales), Leeds (North and North East) and Glasgow (Scotland), supported by regional teams of specially trained engineers, in-field water treatment specialists and technical experts Water Treatment Services can offer professional, cost effective solutions for the treatment of closed circuit heating, cooling and closed loop chilled water systems throughout the UK and Ireland.

Contact us today to learn how our expert water treatment and closed circuit engineering support solutions can help you to save energy, reduce downtime, optimise costs and operational efficiencies, and increase asset reliability. To speak with one of our water treatment experts call us on 0330 223 31 31 or simply use the button below to get our full contact details or submit our contact form.

Contact Us Today

What are closed system water circuits?

Closed systems, closed circuits or closed loop water systems are used in many commercial, industrial and process environments where they provide heating or cooling to work spaces, other internal environments, and manufacturing and industrial processes.

Closed circuits operate as a “closed loop” or “closed system” meaning that they are effectively sealed and the water inside the system is not exposed to the atmosphere. This means that a closed loop system contains a fixed volume of water that recirculates and tends to suffer only negligible water losses.

Problems affecting closed loop systems

If closed loop systems or the water used within them are poorly maintained or left untreated it can lead to problems that will affect energy usage, cost, asset performance and reliability. Specifically, these problems include corrosion, fouling, biofouling and scaling to a lesser extent unless there is significant water loss requiring additional make-up water.

  • Corrosion

  • Fouling

  • Biofouling

  • Scaling

To combat such problems closed loop systems and the water used within them require suitable treatment.

Successful closed circuit water treatment

The successful management of closed loop systems requires a holistic approach to the maintenance and protection of both the system, its components and the water used in them against the detrimental effects of corrosion, fouling, biofouling and scaling.

A well-managed waster system has significant benefits and will help save energy, reduce downtime, optimise costs and operational efficiencies, and increase asset reliability.

Water Treatment Services holistic approach to the successful management of closed loop water systems involves control of the following issues:

  • Corrosion Control

    Appropriate control measures to minimise system corrosion.

  • Control of Fouling

    Controlling system fouling to reduce blockages, maintain energy transfer efficiencies, and flow rates.

  • Controlling Biofouling

    Controlling biofouling from microbial slimes, pseudomonas bacteria, nitrifying and sulphate reducing bacteria.

  • Scale Control

    Scaling in closed circuits is generally less of an issue but can be problematic where significant make-up volumes are required.

Inhibiting corrosion in closed loop water systems

Corrosion can affect closed loop heating, cooling and chilled water systems even though oxygen levels tend to be lower in such fixed volume water systems. However, it is more common in heating systems where higher, fluctuating temperatures can increase rates of corrosion.

Corrosion control is important as if left unchecked it can lead to the degradation of metallic components and increased fouling from corrosion by-products. This can lower flow rates, cause blockages, and reduce reliability and life-expectancy. It can also lower heat transfer efficiencies which increases energy costs.

A thorough understanding of system metallurgy is essential in the development of an effective corrosion control programme. Several different metals are commonly used in closed loop systems and care needs to be taken that any chemical water treatment products selected are compatible. This is especially true for systems that contain aluminium.

Chemical corrosion control can be achieved by incorporating specialist closed loop water treatment technologies including high performance corrosion inhibitors and oxygen scavengers in to the water treatment programme.

Controlling fouling & microbial slimes in closed circuits

Closed circuit water systems can become fouled from sources including suspended solids, corrosion by-products, scaling and the build-up of microbial slimes from pseudomonas bacteria, nitrifying and sulphate reducing bacteria.

The accumulation of such fouling in the form of sludge and suspended solids can cause blockages, reduce heat transfer efficiencies, and constrict flow rates. It can also cause localised corrosion and bioaccumulation.

Pseudomonas bacteria can cause significant microbial fouling issues in closed cooling and chilled water systems. As Pseudomonas bacteria proliferates throughout such closed circuit systems thick microbial slimes can build-up to contaminate the water, reduce cooling efficiencies and increase operating costs.

Successful treatment of closed loop water systems that operate below temperatures of around 80oC should incorporate a broad spectrum biocide to control the growth and build-up of bacteria and microbial slimes within the closed system.

Controlling scale formation

The formation of scale (sometimes called limescale) in closed circuits and closed loop systems tends to be less of an issue because of the fixed volumes of water involved. However, if there are regular water losses that require significant make-up volumes then treatment for scale formation may be required.

This is usually more of an issue with heating systems, especially those using hard water, as the increased system temperatures make the hardness salts more insoluble. The build-up of scale on internal surfaces can cause blockages, reduce heat transfer efficiencies, and constrict flow rates.

Closed systems water treatment training

The industrial and process water treatment specialists at Water Treatment Services have developed an extensive series of professional water and wastewater treatment training courses that includes WTS 0060 “Water Treatment for Closed System Heating & Cooling Water Circuits”. This specialist training for closed systems comprises an intensive one day course designed for facilities managers, water treatment service engineers,  maintenance and engineering contractors, plant operators, and those with responsibility for the installation, pre-commissioning, maintenance and on-going management of commercial and industrial closed water systems used in heating, chilled and cooling water installations… water treatment training →

Expert closed loop water treatment solutions

Contact Water Treatment Services today to discuss your closed loop water treatment requirements. We can provide expert advice and engineering support regarding the management and water treatment of closed loop heating, cooling and closed circuit chilled water systems to help reduce costs, save energy, enhance operational efficiency and reliability, and extend asset lifecycles.

With offices in London serving the South and South East England, Manchester (North West), Birmingham (Midlands), Bristol (South East England and Wales), Leeds (North and North East) and Glasgow (Scotland), supported by regional teams of specially trained engineers, in-field water management specialists and technical experts we can offer professional, cost effective water treatment and engineering services across the whole of the UK and Ireland.

Contact us today for more information or for your FREE, no obligation quote.

Contact Us Today

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Further reading…

More information on closed loop water treatment,  and closed systems water treatment chemicals… here →

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REVIEWS

4.8
Water Treatment Services is rated 4.8 out of 5 stars (based on 103 reviews)
Read our reviews

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