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.

Corrosion is one of the most underestimated risks in commercial HVAC systems. Hidden inside closed heating and cooling circuits, corrosion can develop quietly over months or years before revealing itself through system failure, loss of efficiency, or catastrophic plant damage.

For building owners and facilities managers, the cost of corrosion failure in commercial HVAC systems can easily escalate into six or seven-figure sums once repairs, downtime, tenant disruption, and reputational damage are accounted for. Understanding how corrosion develops, and how real-time monitoring can prevent it, is critical to protecting both assets and budgets.

Why Corrosion Is So Costly in Commercial HVAC Systems

Closed water systems are designed to operate in stable, controlled conditions. When that stability is compromised, corrosion can start to take hold.

The financial impact of corrosion failure typically includes, but isn’t strictly limited to:

• Premature failure of boilers, chillers, pumps, and heat exchangers
• Emergency repair and replacement costs
• System downtime and loss of heating or cooling
• Disruption to occupants, tenants, or business operations
• Increased energy consumption due to reduced heat transfer efficiency
• Insurance claims and potential legal costs

In large commercial buildings such as offices or hospitals, a single corrosion-related failure can trigger cascading problems across the entire HVAC network. When multiplied across multiple assets, the cost of corrosion failure in commercial HVAC systems can quickly stack up.

Air Ingress: The Silent Trigger for Corrosion

The most common cause of corrosion in closed HVAC systems is air ingress. When oxygen enters a closed system, it fundamentally changes the corrosion environment. Dissolved oxygen reacts with metal surfaces, accelerating corrosion of steel, copper, and mixed-metal components. Inhibitors can impede and slow down corrosion, but they should not be seen as a panacea for non-airtight systems. Sudden or long-term pressure drops, and make-up water intake are usually the root cause of air (oxygen) intake.

Crucially, many of these events occur between scheduled water sampling visits, leaving building owners blind to developing risk.

Why Manual Sampling Alone Isn’t Enough

Traditional water sampling remains an important part of HVAC maintenance, but it only provides a snapshot in time.

Manual sampling:

• Cannot detect sudden oxygen ingress events as they occur
• Misses short-term changes in corrosion rates
• Provides limited visibility between service visits
• Often identifies problems only after damage has begun
• Provides limited information on the root cause of any issues

This gap in visibility is a major contributor to the high cost of corrosion failure in commercial HVAC systems.

How Real-Time Monitoring Prevents System Failure

Real-time remote monitoring transforms how closed HVAC systems are protected. By continuously tracking key system parameters, real-time monitoring provides early warning of adverse conditions before they escalate into failures. This includes immediate detection of air ingress, inhibitor dilution, system water contamination and corrosion.

Parameters that can be monitored in real time include:

• Dissolved oxygen
• Make-up water flow
• Pressure
• Temperature
• Conductivity / chemical dosing level
• pH
• Galvanic currents (related to corrosion rate of steel)
• Crevice corrosion

Instead of reacting to failures, the Hevasure team gains the ability to intervene early, investigate root causes, and apply targeted corrective actions. Real-time monitoring is not just about collecting data, it’s about interpretation and action. This proactive approach significantly reduces the likelihood of major component failure and helps extend asset life.

It’s important to note that real-time monitoring does not eliminate the need for periodic sampling. However, continuous monitoring significantly reduces sampling frequency, improves the effectiveness of maintenance visits, and ensures sampling is targeted rather than reactive. Most importantly, it closes the visibility gap that allows corrosion to develop unnoticed.

Protecting Assets, Budgets, and Buildings

In today’s commercial environments, HVAC systems are critical infrastructure. Failure is not just an engineering issue, it’s a financial and operational one.

By addressing air ingress risks and monitoring corrosion conditions in real time, building owners can dramatically reduce or completely avoid corrosion failure in commercial HVAC systems, avoiding unexpected downtime and preserving long-term asset value.

How Hevasure Helps

Hevasure provides real-time remote monitoring of closed water systems, offering early warning of corrosion risk, air ingress, and system instability.

By combining continuous data collection with expert interpretation, Hevasure helps building owners move from reactive maintenance to proactive protection, preventing small issues from becoming million-pound failures.