Recent revisions to BS 7593:2019 have made taking a best practice approach to central heating system maintenance even more vital. Richard Crisp, Head of Chemistry at Fernox, explains more about the standard and the role of testing.

In recent years, the industry has worked to ensure that the use of high quality chemical water treatment and filters is standard practice for professional installers, and the revisions to BS 7593:2019 absolutely reinforce this principle of complementary water treatment. Perhaps one of the most significant additions to BS 7593:2019 is the role that testing should play in central heating system maintenance. 

Under BS 7593:2019, installers are now urged to check inhibitor levels annually and conduct a laboratory test every five years, to identify and prevent any issues. 

Why you should check inhibitor levels annually

If limescale build up and corrosion occurs within the central heating system, sludge and debris will form. These substances can be incredibly harmful to the central heating system, causing blockages in the pipes that force the system to work harder – which can result not only in increased fuel usage, translating into higher fuel bills and increased carbon emissions, but also impacting on the system lifespan and the associated risk of premature breakdown and subsequent costly repair.

Sludge and debris typically cause problems like radiator cold spots and system noise, reducing overall system efficiency.  

Adequately cleaning the system in advance of a new install or combi swap, and dosing the central heating system with a corrosion inhibitor, is therefore vital. An inhibitor actively works to protect the metals commonly found in central heating systems and prevent rust and corrosion formation. However, inhibitor is only effective if the correct quantity is dosed into the system. 

Manufacturers produce test kits that allow installers to conduct analysis of the system water on-site, enabling them to identify any issues quickly and re-dose if necessary. 

For example, the Fernox Universal Test Kit includes everything required to conduct on-site tests for water turbidity, pH levels, and water hardness as well as the presence of chemical water treatment using the Protector Reagent supplied. The kit contains enough equipment to test at least 25 systems and the results are provided in seconds. Similarly, the Fernox Protector Test Kit is an on-site dip test, which determines the concentration level of inhibitor to ensure adequate protection.

The role of laboratory testing

To avoid the risk of chemical degradation over time, BS 7593:2019 recommends that the inhibitor should either be re-dosed at five-year intervals or, a full laboratory analysis of the system water should be undertaken, and the system treated with inhibitor.

To perform a laboratory test, installers should take a sample of the central heating system water and send it off. Results should be turned around quickly to ensure installers can resolve any issues ASAP. 

When working on multiple projects, it can be difficult for installers to keep track of system samples at any given time. Fernox has developed an app designed to help installers comply with British Standards. 

Using the Fernox Water Quality Test app, installers can submit all sample details electronically by scanning the QR code on the sample bottle provided in the kit. Installers then send the physical sample with free next day delivery to the Fernox laboratory. 

Using the QR code as the tracking and matching device, Fernox technicians will then conduct an analysis of key criteria system water parameters. Test results updates, pass and fail, are sent via the app within 24-48 hours of receipt of the sample. 

For installers, all water quality test information is available through the app, providing the ability to review each sample individually, receive confirmation that the system has been correctly treated and fully protected or advice on the appropriate treatment. A full diagnostic report is also sent via email and is accessible via the Fernox web portal.

Testing provides installers with a quick way to comply with BS 7593:2019 and ensure that heating systems are correctly treated. Through annual on-site testing and laboratory testing every five years, installers can easily recognise and rectify any issues with the central heating system, and ensure that optimum performance and efficiency are properly maintained before issues arise.