Corrosion monitoring – spotting and stopping corrosion in closed water systems

25th February 2019

Corrosion in sealed HVAC systems can lead to leaks, costly repairs and system breakdown. To prevent corrosion, buildings must be constructed correctly, water systems pre-commissioned effectively and ongoing maintenance must be preventative, focused on fixing problems rather than masking them with more chemicals.

What causes corrosion in pipework?

Corrosion in pipework is caused by a combination of issues. The presence of bacteria, particularly when it’s sessile and has formed a biofilm is one culprit. Bacteria in isolation is not the route of the cause, however. Bacteria needs oxygen to thrive and dissolved oxygen itself can also cause corrosion. Conversely, some of the treatments for bacteria proliferation can contribute to pipe degradation and consequent corrosion, including over-zealous flushing and chemical dosing.

How can corrosion be prevented?

To prevent corrosion, care must be taken to keep oxygen out from the start; during construction, pre-commissioning cleaning and maintenance. Keeping track of air tightness and pressure once a system is built, being aware of the potential for aeration when new water is added to the system and in our opinion, not relying on sampling as the sole way of understanding system condition.

Sampling has a number of flaws, including the fact in can take weeks for results to be returned, it only represents a snap shot in time and doesn’t effectively detect for dissolved oxygen. We recommend 24/7 real-time monitoring using Hevasure’s innovative technology to ensure a true picture of system condition. With Hevasure, small issues can be flagged-up and dealt with quickly, potentially stopping corrosion altogether.

When should corrosion monitoring start?

Corrosion monitoring should begin during pre-commissioning cleaning and then be carried out throughout a water systems life, to ensure maintenance is fit for purpose, which can lead to a reduction in chemical usage and flushing. Any change in the system has the potential to alter the water conditions and allow oxygen in – when repairs take place, or where different zones are integrated, for example, so it’s vital to keep an eye on what’s happening all the time.

At Guardian we believe sole reliance on sampling as diagnostic practice is outmoded. These days there are more innovative and comprehensive ways to pick up the problems that lead to corrosion. New technologies, such as Hevasure, give building managers and maintenance teams better control of their water systems, enabling them to react quickly to changes in the system’s condition before bigger problems take hold.

Corrosion monitoring prevents breakdown

24/7 corrosion monitoring and analysis is key to a healthy water system. Hevasure’s monitoring technology tracks oxygen, pH and inhibitor levels, as well as pressure and corrosion rates. Live data is sent direct to FMs and building managers inboxes, allowing them to track changes in condition and investigate issues without calling in expensive consultants. Crucially, this approach prevents corrosion and prevents breakdown, a problem which can run into the millions in large commercial buildings.

For more information about Hevasure, click here.