Why chemical water treatment adds up
Published: 05 May, 2016
Investing in chemical water treatment for heating systems makes long-term financial sense — both to maximise energy efficiency and protect equipment, especially boilers. Neville Small of Potterton Commercial takes up the case.
Chemical water treatment is an important aspect of any commercial heating system, whether a replacement boiler is installed into an existing system or an entirely new system is fitted. Although there are numerous benefits to ensuring adequate treatment is in place, it is often overlooked — either due to lack of awareness or budget constraints.
Heating systems, of course, perform better and more reliably with good-quality water circulating in them. However when commercial boilers are being installed and maintained, chemical water treatment is often overlooked.
For many contractors and building managers, this omission is down to a ‘fit-and-forget’ ideology, with ongoing maintenance and whole-life costing often left out of the equation. In fact, recent research by the Carbon Trust found that this is a widespread concern, as two-thirds of surveyed professionals stated they do not fully take into account the whole life costs of equipment when making purchasing decisions.*
The fact is that chemical water treatment should always be incorporated into both the commissioning and ongoing maintenance of a heating system, including a system clean/flush and regular doses of inhibitor as required. This is critical to ensure boiler efficiency and longevity in any commercial heating system, large or small. Even completely new heating systems with new boilers and new pipework need to be chemically treated.
This is because water contains dissolved atmospheric gases, which can affect a heating system’s components. Failing to invest in appropriate water treatment can result in corrosion and the build-up of lime scale — leading to inefficiencies, poor performance and potential boiler failure after a relatively short period of time.
Systems that are corroded become blocked with sludge and debris, which will cause the boiler to work harder and for longer, as the circulating water is unable to transfer the heat efficiently throughout the system. This drastically reduces energy efficiency, in turn increasing running costs as well as carbon emissions.
Meanwhile, limescale deposits on heat-transfer surfaces compromise efficiency, as the boiler has to run hotter for longer. Hard water affects over 60% of England, and most commercial heating systems installed in buildings located in the south, east and middle of the UK will be subject to the detrimental effects of lime scale if ignored.
The build-up of scale and debris can also cause noise in the boiler, as well as high temperatures due to little or no flow, which can result in failure of significant parts of the system.
Corrosion and limescale have a negative impact on system operation and boiler and component longevity. It might sound sensational, but failing to clean, flush and inhibit a system adequately could mean that the boiler could break down in a matter of months or, even, weeks. This of course causes unnecessary cost and the inconvenience of system downtime, which can affect productivity of building users and in some cases result in temporary shutdown.
In addition to affecting efficiency and performance, poor water treatment can, in some cases, invalidate the boiler manufacturer’s warranty.
We appreciate that some customers might be reluctant to spend extra money on water treatment — either as a result of budget constraints or a lack of awareness about how important it is. However, although it might seem like a costly exercise, an appropriate water treatment programme, in line with the boiler manufacturer’s recommendations, can pay dividends.
BSRIA, ICOM and leading boiler manufacturers all recommend flushing, chemical cleaning and the use of appropriate inhibitors. In terms of the processes involved, a chemical clean, ideally in conjunction with a power flush, should be the first step, even if the boiler and pipework are new. If a new boiler is being installed on an old system, we recommend a gentle neutral-pH clean four to six weeks prior to the installation, followed by a more aggressive (though still neutral-pH) chemical clean over one to two days, along with power flushing.
Following this, an initial dose, and ongoing use, of a high-quality inhibitor will prevent corrosion and any further build-up of limescale, helping to maintain boiler efficiency and extend the life of the system.
The chemicals used must be in line with the boiler manufacturer’s recommendations, which can usually be found in the installation manual. As inhibitors need be applied on an ongoing basis as required, it is important for the person responsible for maintaining the heating system to be able to find and refer to this information — so the installer should point it out at handover. We know of at least one case where a new commercial boiler, professionally installed in perfect condition, broke down under a year after installation because the incorrect water treatment chemicals were used.
We suggest that water quality is routinely checked (simple testing kits are available from companies such as Sentinel and Fernox) and that it becomes part of the maintenance programme. The ongoing testing of water quality can highlight any issues early on, and will indicate if inhibitor levels have depleted, helping to save money in the long run. This approach is again recommended by BSRIA, ICOM and leading commercial-boiler manufacturers.
Adding central-heating filters as part of routine service and maintenance to capture any circulating contaminants within the system can also improve system efficiency and longevity, and is well worth the extra investment. Filters are not a substitute for chemical water treatment, however, as they cannot prevent corrosion.
Although often overlooked, adequate water treatment can not only help save energy but also extend the life of a boiler and improve reliability. It should therefore be top of the list of any heating system installation or upgrade, with the many benefits outweighing the cost of investment.
Neville Small is sales director at Potterton Commercial.