The Viessmann Group is a German manufacturer of heating and refrigeration systems headquartered in Allendorf (Eder), Germany.

[4] In April 2023, Viessmann announced that it would sell its heat pump division to its US competitor Carrier Global for €12 billion.

Maximilian Viessmann has assumed responsibility for whole group as CEO, while Ulrich Hüllmann fulfills the position of the CFO.

[9] For the company's 100th anniversary in 2017, a new research and development center was inaugurated at the headquarters in Allendorf in the presence of German Chancellor Angela Merkel.

In September 2016, Viessmann launched heizung.de, an information and advice portal aimed specifically at end users such as new builders and refurbishment companies.

After World War II, Hans Vießmann took over his father's company and modernized it by introducing series production and industrial processes.

In 1972, Viessmann opened its first foreign factory in Faulquemont (France), followed by Waterloo, Ontario (Canada), the first site outside Europe, in 1978.

With the development of new technologies, the company responded to the challenges of the energy crisis: In 1976, the first solar collectors were produced, followed by the first heat pumps in 1978.

Viessmann set up a new production facility for wall mounted gas boilers in Allendorf, whilst developing an international sales office and branch network.

In biathlon, the team includes Sven Fischer, Laura Dahlmeier, Denise Herrmann, Franziska Hildebrand, Benedikt Doll and Arnd Peiffer.

The Nordic combined athletes Eric Frenzel and Johannes Rydzek are in the Viessmann team, as well as ski jumpers Katharina Althaus, Stephan Leyhe, Richard Freitag and Markus Eisenbichler and one of the greatest German talents Constantin Schmid.