Monitoring detects problems that sampling fails to identify

Monitoring detects problems that sampling fails to identify

We have helped Guardian Water Treatment prevent a major breakdown of the heating system at Telephone House on London’s Embankment, by using our real-time monitoring and diagnostic tool to help determine the cause of corrosion and radiator leakage – an issue that would have eventually led to expensive repairs and loss of revenue.

Despite the fact that traditional sampling tests showed BSRIA chemistry and bacteria to be within guideline limits and that iron levels and solids were both within range, the radiators at Telephone House were leaking on an increasingly regular basis. Hevasure’s sister company Midland Corrosion’s analysis of the damaged pipes and radiators cited gross aeration as the problem, demonstrated by oxide deposits in the radiators’ water channels. These deposits (mainly magnetite sludge) had not been detected through water analysis due to low solubility and settling within regions of the system with low flow rates.

As a first step, the Hevasure unit was installed in the building’s basement for an initial three-month period of monitoring. Analysis of the readings pointed to a loss of pressure on the building’s fourth floor when the system was at rest. Hevasure’s data identified that when the water in the heating system was cooler, the pressure dropped and oxygen levels spiked. When the system was hot and the pressure more stable, the DO levels were seen to reduce.

On analysis of these results, Guardian was able to recommend that the client undertake a series of simple measures and adjustments, including repairs to the expansion vessels, pressurisation units and AAV’s. Once these straight-forward fixes were complete, Hevasure’s readings confirmed that the DO levels were no longer of concern. Corrosion rates became negligible and inhibitors were effective.

The project has been a great success – Guardian’s client was so impressed that they extended the period of Hevasure analysis for another five months. Because potential problems were flagged up early enough, the building’s maintenance teams could stop the cause of air ingress before it got out of hand, ensuring the heating system in this prestigious listed office building, remained operational.

Both sampling and flushing – traditional approaches to understanding and treating water system issues – were ineffective in this instance. By using Hevasure, the root cause of aeration could be identified and fixed, saving huge amounts of money long term.

  • Monitoring identified problems undetectable by sampling
  • Chemical usage was reduced
  • Flushing was not required
  • Breakdown and expensive repairs were avoided
  • The problem was fixed, not masked

To read the full case study, please click here: Telephone House case study