Under ErP, what about systems that contain different products?
In these circumstances, there is a responsibility to provide a package label when combining a heating appliance with a temperature control and/or solar system with a cylinder and/or a supplementary heating appliance (e.g. a two boiler cascade with a combined output of less than 70kW).
The person who puts that package together will need to produce a package document known as a fiche (data table) and a label that provides the combined energy efficiency rating rather than ratings of each individual component. For example, this could be the merchant's responsibility if they supply a complete package under one part number or your responsibility if the items are bought individually under separate part numbers.