We’re delighted to share that Steve Munn, Managing Director of Hevasure, recently joined Simon Woodward, Chairman of the UK District Energy Association (UKDEA), for an episode of the UKDEA Podcast.

During the discussion, Steve explores the growing importance of real-time water quality monitoring in protecting heat networks from corrosion and maintaining long-term system performance.

As the heat network sector continues to evolve and the Heat Network Technical Assurance Scheme (HNTAS) approaches, continuous monitoring is becoming an increasingly important part of effective system management. The conversation covers how real-time monitoring can help operators identify issues early, reduce corrosion risk, improve reliability, and support the long-term efficiency of closed heating and chilled water systems.

The episode also highlights the role intelligent monitoring can play in helping heat network operators prepare for future industry requirements and adopt a more proactive approach to water quality management.

Whether you’re responsible for the design, operation or maintenance of a heat network, or you’re looking to understand the impact of upcoming HNTAS legislation, this episode provides valuable insight into one of the industry’s most important topics.

We’d like to thank Simon Woodward and the UKDEA for the opportunity to discuss the future of heat network monitoring and share Hevasure’s experience gained from over 12 years of monitoring closed heating and chilled water systems across the UK.

Listen Now

You can download the episode from your preferred podcast platform or watch it on the UKDEA YouTube channel here:

As the UK heat network sector continues to evolve, there is increasing discussion around adopting the VDI approach commonly used across large parts of Europe. This represents a significant shift in how closed heating and chilled water systems are designed, maintained, and protected against corrosion.

Traditionally, in the UK, most closed systems rely on chemical inhibitors to reduce the risk of corrosion. These inhibitors act as a second line of defence by passivating metal surfaces and suppressing corrosion if, and when, oxygen enters the system. This has long been the standard approach across commercial heating and cooling systems as covered by BSRIA guidelines BG29 and BG50.

However, in many European markets operating under the VDI 2035 standard, systems are designed to operate without chemical inhibitors. Instead, they rely on higher engineering standards to minimise oxygen ingress and use much purer, low-conductivity water within the system.

The theory behind this approach is straightforward: prevent oxygen ingress from occurring in the first place while reducing the conductivity of the system water to minimise corrosion currents. But in practice, this also means that chemical-free systems can become more vulnerable if oxygen does enter the system, as there is no inhibitor present to suppress corrosion activity.

This is one of the reasons why continuous, real-time monitoring is becoming increasingly important as the UK market explores wider adoption of VDI 2035 principles.

In fact, the draft TS1 Heat Network Technical Standard highlights the importance of monitoring both chemically inhibited and chemical-free (depleted water) systems to ensure long-term system integrity and operational efficiency.

This is where Hevasure’s technology is uniquely positioned.

Unlike some monitoring solutions focused solely on chemical-free systems, Hevasure’s real- time monitoring technology supports both chemically inhibited and VDI-style chemical-free systems.

For chemically inhibited systems, our monitoring technology continuously checks that inhibitor concentration does not fall below an effective level. This ensures the system maintains its protective corrosion barrier and allows operators to intervene early if dilution or system losses occur.

For chemical-free (depleted) systems, Hevasure continuously monitors conductivity to ensure water quality remains within VDI 2035 operating parameters – typically below 100 micro-

Siemens. This is critical, as increases in conductivity can indicate contamination or changes in system conditions that increase corrosion risk.

Importantly, across both approaches, the fundamentals remain the same. Oxygen ingress, pH instability, and active corrosion remain the key threats to long-term system health.

This is why Hevasure continues to monitor critical parameters, including:
● Dissolved oxygen
● Conductivity
● pH
● Corrosion activity

By continuously analysing these parameters in real time, operators gain complete visibility into system behaviour and can identify issues before they develop into serious failures.

With over 12 years of experience and approaching 200 installations across the UK, and now in its fourth generation of product development, Hevasure has built its reputation on delivering intelligent corrosion control for real-world operating systems.

As the UK market moves towards broader adoption of VDI principles and TS1 requirements continue to evolve, the need for reliable, adaptable monitoring technology will only increase.

Hevasure is already ready for both worlds.

Whether your system uses chemical inhibitors or follows a VDI chemical-free approach, Hevasure’s real-time monitoring technology provides the visibility needed to protect system integrity, maintain compliance, and reduce corrosion risk. Contact us today to find out how we can support your heat network.

Corrosion remains one of the biggest threats to the reliability and lifespan of closed heating and chilled water systems.

At Hevasure, we are proud to say that in over 12 years of monitoring almost 200 closed systems (heating and chilled water) across the UK, we have never had a single system fail due to corrosion damage while under our watch. That is a 100% record – and one we believe speaks volumes about the value of continuous, intelligent monitoring.

Over the last decade, real-time monitoring has evolved from an emerging concept into a critical part of maintaining modern heating and cooling infrastructure. During that time, Hevasure has remained at the forefront of the industry, pioneering remote water quality monitoring technology designed specifically to protect closed systems from corrosion, inefficiency, and avoidable failure.

Our monitoring systems are currently used across a wide range of sectors, including:

● Commercial offices
● Government buildings
● District heating schemes and heat networks
● Hospitals
● Universities
● Data centres

Each of these environments presents different operational challenges, but they all share one common requirement – maintaining water quality and preventing corrosion in their closed systems before costly damage occurs.

This is where Hevasure’s technology continues to lead the way.

Our flagship product, the Aquila-2, is now in its fourth generation following years of extensive research, development, and innovation. Designed specifically for closed heating and chilled water systems, it continuously monitors critical system parameters in real time, including dissolved oxygen, conductivity, pH, pressure, and corrosion activity.

This continuous visibility allows maintenance teams to quickly identify abnormal behaviour, investigate root causes, and intervene before issues escalate into serious failures.

Importantly, our approach is not reactive. We do not wait for corrosion damage to appear before action is taken. By continuously monitoring system conditions, our technology enables operators to spot trends, identify risks early, and maintain long-term system stability.

Over the years, this has allowed our clients to avoid the costly consequences of hidden leaks, oxygen ingress, unstable pressurisation, contamination events, and inhibitor dilution – all common causes of corrosion within closed systems.

We are justifiably proud not only of our technology, but of what it has helped deliver to our clients over the last 12 years:

● Reliable systems
● Efficient operation
● Reduced maintenance risk
● Long-term asset protection
● Corrosion-free systems

As heat networks and commercial building infrastructure continue to evolve, the importance of intelligent monitoring will only increase. But while the industry continues to change, our focus remains the same – protecting systems before failures occur.

After nearly 200 monitored systems and more than a decade of operation, our record speaks for itself.

If you want to protect your closed heating or chilled water system with proven monitoring technology trusted across the UK, contact Hevasure today to find out how our real-time monitoring solutions can help safeguard your assets for the long term.

The UK heat network sector is entering a new era.

Heat network regulations are undergoing fundamental changes, with Ofgem officially taking on regulatory responsibility for heat networks across Great Britain. This marks one of the most significant shifts the sector has seen to date.

For building owners, operators, FM teams and consultants, these changes are about far more than compliance. They signal a clear move toward greater accountability, stronger consumer protections, improved operational transparency, and higher technical standards across the entire heat network landscape.

Reactive maintenance and periodic checks are no longer enough for operators expected to demonstrate system reliability and proactive management. This is exactly why real-time monitoring is becoming essential, and why more organisations are turning to Hevasure.

Why Heat Network Regulations Are Changing

Heat networks are expected to play a major role in the UK’s decarbonisation strategy. Government targets indicate heat networks could supply a significantly larger proportion of UK heating demand in the coming decades as the country works toward net zero.

But as the sector grows, so too has scrutiny around performance. These challenges prompted a long-awaited regulatory overhaul. The result is a new framework designed to professionalise the sector and build greater trust.

Ofgem

As of 27 January 2026, Ofgem has formally become the statutory regulator for heat networks in Great Britain under the Heat Networks (Market Framework) Regulations 2025. This is a landmark change for the industry. It means heat network operators are now subject to regulatory oversight similar in principle to other utility sectors.

The immediate focus of Ofgem’s framework is consumer protection. One of the key priorities involved in this is that of service reliability. Operators are expected to deliver consistent service standards and demonstrate effective operational management in order to be compliant. This is where technical performance and monitoring become increasingly important.

Why Operational Visibility Matters

Reliable service cannot be achieved without reliable systems. And reliable systems depend on visibility. Traditional water sampling has an important role, but it only provides a snapshot. It cannot identify developing issues the moment they emerge, which is a key component of staying compliant with these new regulations.

The Technical Standards Shift

Alongside Ofgem’s consumer protection framework, further technical assurance measures are on the horizon through the Heat Network Technical Assurance Scheme (HNTAS), which will be overseen by Ofgem. This will introduce mandatory technical standards across heat networks, including requirements around system monitoring and operational performance.

As heat network regulations evolve, continuous monitoring is a strategic necessity. Hevasure’s real-time remote monitoring technology is designed specifically for closed water systems. When system failures affect service continuity, consumer outcomes are impacted. With regulation changes on the horizon, it’s incredibly important that businesses get protection in place sooner rather than later.

A Practical Compliance Checklist

For operators assessing their readiness, the following areas are worth reviewing now:

• Registration: Complete registration with Ofgem by 27 January 2027.
• Authorisation conditions: General conditions took effect 27 January 2026 – review your obligations under the Market Framework Regulations 2025.
• Data reporting: Establish systems for quarterly and annual reporting; annual submissions are generally due by 30 April.
• Metering and monitoring: The draft Metering and Monitoring Standard requires a structured Automatic and Remote Monitoring System (ARMS), with data storage, fault reporting, and data access.
• HNTAS readiness: Begin reviewing the HNTAS technical feedback process, which outlines how the scheme, planned for launch in 2027, will apply to new and existing networks.
• Water quality records: The draft TS1 standard requires commissioning to include acceptance testing and recording of water quality parameters, with verification that they are within control limits.

Preparing for the Future

The regulatory direction is clear. Heat networks are moving toward the same expectations of accountability, transparency, and technical performance seen elsewhere in the energy sector.

As HNTAS and further technical requirements emerge, operational data and real-time insight will become increasingly valuable. For building operators, consultants, and asset managers, now is the time to assess whether their systems are truly prepared.

Hevasure can help your business meet these requirements. To learn more or discuss your specific needs, please contact us today at 01629 735743 or via email at info@hevasure.com.

Key Takeaways

• As of 27 January 2026, Ofgem enforces new heat network regulation under the Heat Networks (Market Framework) Regulations 2025, bringing stricter oversight and accountability to the sector.
• Operators must now demonstrate system reliability and proactive management to comply with updated consumer protection standards.
• Continuous real-time monitoring provides the operational visibility necessary to meet mandatory technical standards like the upcoming HNTAS, planned for 2027.

Frequently Asked Questions

When does heat network regulation start and who oversees it?

Ofgem is the statutory regulator for heat networks across Great Britain. The first general authorisation conditions officially entered into force on 27 January 2026. The regime is introduced in phases, focusing heavily on reliable customer service and fair energy pricing. You can read more about the rollout directly on the Ofgem website.

Do all systems fall under heat network regulation for registration?

Most district and communal networks are in scope and must be registered by 27 January 2027. Registration requires operators to use the Ofgem digital portal to share ownership and consumer protection details. 

How does real-time visibility assist with upcoming regulations?

The regulatory shift places a clear emphasis on consistent technical performance rather than occasional spot checks. Continuous monitoring tracks parameters like pressure and dissolved oxygen in real-time. This evidence-based approach helps operators spot developing issues instantly, keeping maintenance proactive and avoiding costly system downtime.

Hevasure in Action

Pressure stability is critical in maintaining the health of closed heating and chilled water systems, whether it be in commercial buildings or heat networks. When pressure fluctuates and drops to negative values at the top of the system, the impact can directly contribute to increased corrosion risk and reduced system lifespan. Gaseous air is effectively sucked into the system through air vents and weak seals/joints raising dissolved oxygen to dangerous levels.

In real-world operation, pressure issues are not theoretical risks. They are common events that the Hevasure monitoring systems actively detect and help resolve before significant damage occurs.

Fluctuations in pressure can be due to several reasons. Often, we will see sudden pressure drops caused by partial system drain-down during maintenance. Sometimes we see pressure decreasing on cooling, indicating that the pressurisation unit is not properly set up. And, as in the recent case of a large commercial office in London, we see pressure fluctuating on a periodic 24-hour cycle with corresponding increases in dissolved oxygen (figure 1). In this particular case, Hevasure alerted the maintenance team, who were able to quickly deduce the root cause by looking at the BMS activity at the relevant times. The problem was caused by pumps being switched off overnight, reducing the dynamic pressure in the system. In effect, the static pressure was insufficient to hold up 30m of water, resulting in air being sucked into the system at the upper levels of the building. Having identified the root cause, the solution was obvious: either increase the static pressure or, preferably, keep all the pumps running.

Conventional water sampling would not have picked this issue up. However, with the Hevasure Aquila-2c system in operation, simultaneous changes in multiple parameters (pressure, dissolved oxygen and corrosion rates) made it relatively straightforward to notice that something was wrong and deduce an appropriate corrective action.

With over 12 years of experience and more than 175 installations across the UK, our Aquila system is designed specifically to detect these complex, time-dependent behaviours. Now in its fourth generation, it delivers not just alerts, but a deep understanding of how systems are performing in real time.

This allows operators to move from reactive maintenance to proactive intervention, reducing corrosion risk, lowering maintenance costs, and extending overall system lifespan.

If you suspect pressure fluctuations may be affecting your system, get in touch to see how real- time monitoring can reveal hidden patterns and help protect your asset before damage occurs.

Water quality within a closed heating and chilled water system should remain stable over time. When it changes unexpectedly, it is often a clear indication that the system has been compromised and requires immediate investigation.

In real-world operation, these are not theoretical risks – they are live events that our monitoring systems actively detect and escalate.

A recent example involved cross-contamination of water in a CHW system due to negligence – detected by an abrupt and unexpected change in dissolved oxygen, conductivity and pH. Since the Hevasure Aquila-2 system captures multiple parameters and applies a date/time stamp against all readings, this allowed the building owner to identify exactly when the contamination occurred and identify the guilty party.

What made this particularly critical was the speed of change. These were not gradual variations associated with normal system fluctuations, but sudden and large deviations that signalled an external influence had compromised water quality. In effect this was like a ‘smoking gun’, and the contractor responsible had no hiding place. They agreed to flush and re-dose the system at their own expense, returning the water to an acceptable level of quality.

Without continuous monitoring in place, this type of event would typically only be identified during routine sampling, and the time of the cross-contamination would not have been deduced. Perhaps more importantly, corrosion and system degradation would almost certainly have begun.

With over 12 years of experience and 200 installations across the UK, our Aquila system has repeatedly proven its ability to detect these sudden and critical changes in real operating environments.

Now in its fourth generation, it provides not just data, but immediate insight into system behaviour – enabling fast, informed intervention when it matters most.

If you want to see how real-time monitoring is identifying cross-contamination events in live systems and preventing costly damage, get in touch to learn how Hevasure can protect your installation.

info@hevasure.com

Detecting water leaks and identifying appropriate intervention.

In closed heating and chilled water systems, even small faults can escalate quickly if they go undetected. One of the most disruptive issues we see in practice is a sudden or intermittent water leak. If not identified early, it not only leads to collateral flooding damage but also allows fresh aerated water to enter the system, raising dissolved oxygen and diluting inhibitors.

This is exactly what happened in a hospital’s LTHW system monitored by Hevasure. Over the course of a few weeks, we detected several intermittent leaks by measuring flow rates on the water make-up line and corresponding changes in dissolved oxygen and conductivity levels.

What made this case particularly significant was that the leak was not readily visible, as it was hidden behind plantroom walls. Routine water sampling would not have picked this up, but by measuring multiple parameters in real-time, the Hevasure system flagged up the problem straight away. The Hevasure system data told a clear and consistent story. While the inline water meter readings confirmed the unexpected demand for fresh make-up water, high dissolved oxygen levels and reduced conductivity readings pointed to potential corrosion issues if not remedied. Taken individually, these readings would only give a partial picture. But together, they provided a clear diagnostic picture that allowed the root cause to be identified and appropriate interventions to be made.

Without this level of continuous monitoring, the leak would likely have remained undetected for an extended period, gradually degrading water quality and accelerating corrosion across the system. But with Hevasure’s real-time monitoring in place, the event was identified early, enabling engineers to locate the source of the leak and take corrective action before any major system failure occurred.

This is not a theoretical benefit – it is a practical example of how continuous data visibility changes outcomes on live systems. With over 12 years of experience and approaching 200 installations across the UK, our Aquila system has repeatedly demonstrated its ability to detect exactly these types of intermittent, high-risk events.

Now in its fourth generation, the system is designed not just to show that something is wrong, but to provide the clarity needed to understand what is happening and why – in real time.

By identifying issues early and enabling targeted intervention, downtime is reduced, system damage is prevented, and asset lifespan is significantly extended.

If you want to see how real-time monitoring is actively identifying hidden leaks in live systems, get in touch to learn how Hevasure can help protect your installation and prevent costly failures.

info@hevasure.com

Hevasure technology ensures compliance with HNTAS and TAS1

The newly released draft of the Heat Network Technical Assurance Scheme (HNTAS) and accompanying Technical Standard TAS1 (2025) marks a significant shift in how heat networks will be designed, commissioned, and maintained as the UK targets 20% of national heat demand being met through heat networks by 2050.

A major pillar of TAS1 is the requirement for continuous, realtime monitoring of water quality in both chemically treated and chemically depleted closed systems. To protect asset integrity, prevent unplanned outages, and maximise thermal efficiency, operators will now be expected to track key system health indicators, including:

• Top-up volume
• Corrosion rate
• Conductivity
• pH
• Dissolved Oxygen (DO)

Hevasure has been at the forefront of real-time closed system water monitoring for more than a decade. Our advanced sensor and data acquisition technology, combined with sophisticated analytics, are already aligned with the requirements of
TAS1, providing heat network designers, installers, and maintenance teams with a robust solution for achieving full compliance.

With 12 years of field-proven expertise, Hevasure offers the insight and tools needed to protect system performance, extend asset life, and ensure adherence to the upcoming HNTAS framework.

Learn more at www.hevasure.com.

At Hevasure, we understand that maintaining the integrity of closed heating and cooling systems is critical for commercial buildings. For over 10 years, we’ve been at the forefront of preventing costly damage caused by corrosion. Our 24/7 remote monitoring technology provides truly intelligent corrosion prevention, offering unprecedented insight into your system’s health and proactively tackling a significant threat: oxygen-induced corrosion, especially in modern thin-walled steel pipework.

Over 50% of commercial buildings are under threat from corrosion in their closed-systems. This isn’t just about minor aesthetic damage; it’s about compromised efficiency, expensive repairs, and potential system failure. Our goal at Hevasure is to eliminate these consequences by offering a solution that provides continuous vigilance and actionable data.

Why traditional methods fall short 

Historically, managing water quality in closed systems relied on periodic water sampling and chemical dosing. While these methods have their place, they present significant limitations in comparison to intelligent corrosion control. This is why Hevasure pioneered real-time monitoring technology. Our approach moves beyond reactive troubleshooting to proactive, continuous monitoring of closed-circuit water quality, empowering facilities managers and building owners to maintain optimal system health at all times.

Hevasure’s Aquila-2 range: the pinnacle of intelligent corrosion control

Our flagship Aquila-2 product range, including the Aquila-2+ and Aquila-s models, provides the foundation for our intelligent corrosion control solution. These devices constantly monitor key parameters that indicate the likelihood and rate of corrosion, especially oxygen levels. The Aquila-2+, for instance, monitors several critical parameters, including:

• Dissolved oxygen – the primary corrosion driver
• Corrosion rate
• System Pressure
• Temperature
• Conductivity
• pH

How it works

1. 24/7 data acquisition: Our Aquila-2 units continuously collect data from your closed system.
2. Real-time data transmission: Data is sent securely to our cloud-based dashboard via 4G.
3. Intelligent analysis: Our system analyses trends and identifies anomalies that suggest potential issues, such as oxygen ingress or a rise in corrosion rates.
4. Instant alerts: You or your water treatment specialist receive immediate alerts via email or SMS when parameters exceed safe thresholds. This allows for rapid intervention.
5. Comprehensive dashboard: Our intuitive dashboard provides a clear, real-time overview of your system’s health, historical data, and trend analysis.

This continuous insight means you’re always informed. Instead of waiting for a quarterly sample to reveal a problem, you can act within hours, preventing minor issues from escalating into major system failures. This is the essence of intelligent corrosion control.

The Benefits

Implementing Hevasure’s intelligent corrosion control delivers a tangible return on investment across several key areas:

• Reduced operational costs: Preventing corrosion extends the lifespan of assets, reduces the need for costly repairs and component replacement, and maintains system efficiency, leading to lower energy bills. We’ve seen firsthand how our technology helps avoid the pricey cost of corrosion failure in HVAC systems.
• Enhanced system longevity: Proactive intervention ensures your heating and cooling systems operate optimally for longer, protecting your investment.
• Improved reliability and uptime: Minimising corrosion-related failures means fewer unexpected breakdowns and less disruptive downtime for your commercial operations.
• Sustainability: Efficient systems consume less energy and water, contributing to your building’s sustainability goals and reducing its environmental footprint. Using HVAC monitoring to ensure system sustainability is a core benefit.
• Peace of mind: Knowing your systems are constantly monitored by intelligent corrosion control technology frees you to focus on other priorities.

Protecting your closed heating and cooling systems from corrosion, particularly the silent threat of oxygen-induced damage, is no longer a reactive task. With Hevasure’s 24/7 remote monitoring technology, you gain truly intelligent corrosion control. Our Aquila-2 range provides the essential data, real-time alerts, and comprehensive overview needed to maintain optimal water quality, extend asset life, and secure operational efficiency.

Don’t let corrosion silently erode your investment. Embrace the future of intelligent corrosion control with Hevasure. To learn more or discuss your specific needs, please contact us today at 01629 735743 or via email at info@hevasure.com.

Hevasure is proud to announce that we are now approved by the CIBSE (Chartered Institute of Building Services Engineers) to deliver a CPD (Continuous Professional Development) focused on real-time monitoring of closed heating and cooling systems.

This CPD has been developed specifically for building services professionals, consultants, facilities managers, and building owners who are responsible for the performance, longevity, and compliance of LTHW and CHW systems. As awareness grows around the true cost of corrosion and system failure, the need for better insight into closed water systems has never been greater.

The CPD draws on real-world experience, data, and live system monitoring to move beyond theory and address the practical realities faced in commercial buildings today.

Hevasure will explore several key points regarding closed water systems, including:

• The ongoing reality of corrosion risk in operational LTHW and CHW systems
• The limitations of relying solely on periodic water analysis
• What building owners and operators should expect from an effective monitoring system
• The practical benefits of continuous monitoring for closed heating systems

The CPD also includes an overview of real-time monitoring in operation, using Hevasure’s Aquila-2 range as a practical reference point, along with case studies.

The approval of this CPD by the CIBSE reflects the growing importance of real-time data in managing closed heating and cooling systems. With increasing pressure on system reliability, energy efficiency, and lifecycle costs, continuous monitoring offers a more robust foundation for informed decision-making.

Hevasure’s CPD is intended to support professionals who are already operating in this space and want to better understand how real-time monitoring fits into modern best practice. 

With over a decade of experience in closed water system performance and monitoring, Hevasure remains at the forefront of the industry in helping building owners and engineers move from reactive maintenance to proactive system management. With the topics set out in this CPD, Hevasure continues to set the benchmark for modern closed water monitoring solutions, supporting safer, more resilient, and more efficient heating and cooling systems across the built environment.

If you think your organisation would benefit from an online or in-person delivery of this CBD, please reach out to info@hevasure.com.