Installers have been urged to take extra caution over their choice of boiler components and accessories, amid a growing number of controls and flue systems being sold on the internet as compatible with certain manufacturers’ boiler models.

The warning comes from Martyn Bridges, director of technical communication and product management at Worcester, Bosch Group, who believes installers could run the risk of compromising their customers’ safety by fitting flue plume redirection kits which haven’t been tested, approved or certified for use with their boiler.

Mr Bridges said: “We’re seeing a growing number of suppliers selling generic heating accessories such as flue kits that they claim are compatible with a given manufacturer’s boiler, but have never actually been tested to the required standards.

“While these products may match the physical size and dimensions of the manufacturer’s flue, it is important for installers to realise that the absence of a CE mark means there is no proof that they meet the UK’s safety, health and environmental requirements. Worse still, with no testing having taken place, there is no evidence or guarantee that the flue kit won’t be susceptible to damage such as freezing, cracking, or degrading in the sun.”

Boiler manufacturers in the UK generally have their appliances and flue systems approved to C1, C3 and C5 classifications, which are essentially horizontal, vertical and flue plume redirection categories. Under these categories, the manufacturers are required to have their boiler and flue system approved as a partnership, and with good reason according to Mr Bridges.

The generic alternative may be cheaper and its aesthetics might appeal, but Mr Bridges warns that buying one is a risky move for something as critical as a flue system – not least because it will not hold the essential CE marking and will also invalidate the boiler’s warranty.

Mr Bridges believes the rise in the number of generic, third-party boiler accessories available means installers need to be extra cautious with their product selection.

He continued: “There is a plethora of replica boiler accessories being launched into the market and we’ve seen issues where installers and homeowners have been caught out by third-party timers and controls which are not covered by the boiler manufacturer’s warranty. This in turn places much greater emphasis on the need for installers to be vigilant when selecting the most suitable appliances and accessories for their customer’s property.”