The Manufacturers’ Association of Radiators and Convectors (MARC) has issued a reminder for everyone to ‘check the radiator data’ ahead of National Radiator Day on 1 November.
MARC has highlighted the importance of recognised testing, compliant Declarations of Performance (DoPs) and transparent heat-output claims across product literature, websites, catalogues and advertising.
The association said accurate heat-output figures and clear product information are essential to compliance, consumer confidence and effective heating design. So, MARC has urged radiator manufacturers, importers, distributors, wholesalers and resellers to check that their product data is accurate, properly evidenced and consistently presented. Installers also need to ensure that the radiators they are fitting carry compliant Declarations of Performance (DoPs).
Hydronic radiators, including steel panel, multicolumn, designer radiators and towel rails, fall within the scope of BS EN 442. MARC added that manufacturers must ensure that declared performance is supported by the relevant evidence and that a DOP is available for the product, either digitally or in paper form.
Heat output should be declared in watts at both Delta T 50 (ΔT50) and Delta T 30 (ΔT30), supported by appropriate test evidence. These figures provide a consistent basis for comparing radiator performance and calculating the heat required to warm a room.
Delta T refers to the difference between the average water temperature in a radiator and the surrounding room temperature. As radiator output varies with operating temperatures, the association noted that it is essential that performance figures are presented clearly and on a consistent basis.
MARC is particularly concerned about the use of Delta T 60 (ΔT60) or higher figures in place of the recognised ΔT50 and ΔT30 values. Although a radiator produces more heat at a greater temperature difference, it stated that presenting a higher figure without clear context can give customers a misleading impression of the output they can expect.
Andy Phillips, chair of MARC, said: “National Radiator Day is an opportunity to remind the industry that accurate product data matters. Manufacturers and suppliers should check that their heat-output claims are supported by the appropriate test evidence, that their Declarations of Performance contain the relevant information, and that figures are consistent across all their sales and marketing channels.
“Clear, reliable information helps customers compare products fairly, enables installers to make informed choices and supports confidence in our industry.”
MARC is working with the Office for Product Safety and Standards (OPSS) to promote compliance and improve transparency across the sector.
Duncan Johnson, deputy director of Construction Products Regulation at OPSS, added: “We are delighted to be working with MARC to address the challenges being faced in the radiator industry, helping to ensure that manufacturers and suppliers are providing information that is both accurate and compliant with the standard.”