The widely used panel radiators demonstrate the latest evolution from the original sectional or ribbed radiators. Unlike those, they do not consist of individual links, but of one or more smooth or slightly profiled heating plates through which the warm water flows. Between these are convection plates, past which indoor air flows.
The type designation of the radiators depends on the design. It consists of two numbers, the first indicating the number of heating plates and the second the number of convection plates. A type 21 model, for example, consists of two radiator plates and one convector plate. The basic principle here is: the higher the number of convection plates, the higher the proportion of convection heat. Viessmann offers corresponding radiators as universal radiators as well as panel radiators. The latter are best characterised by their smooth surfaces and visually slim design. The radiators are basically available in different connection variants, for example as centre connection radiators. This offers even more flexibility.