ONI-Wärmetrafo GmbH

From a garage to a leading company in building technology! ONI-Wärmtrafo GmbH was founded in 1983 by Wolfgang Oehm and has since grown steadily into a successful corporate group. Today, the ONI Group comprises - the ONI-Wärmetrafo GmbH in Lindlar - ONI Energy Saving Technology Co., Ltd., in Kunshan (China) - ONI Systems de Mexico, S. de R.L. de C.V. (Mexico) - as well as ONI Temperiertechnik Rhytemper GmbH in Großröhrsdorf. The ONI Group serves more than 6,400 customers in 70 countries, employs over 450 people, and specializes in the holistic and intelligent integration of individual systems into highly efficient and sustainable comprehensive systems for building, process, and water technology . From design through delivery and commissioning to 24/7 service , the ONI Group offers comprehensive “one-stop” solutions . Its extensive portfolio of products and services, along with numerous unique selling points, make the group a recognized innovation leader in the industry. The group has filed patent applications for numerous individual products and system solutions and has been honored with more than 50 national and international prizes and awards . These include, among others, an entry in the “Lexicon of German World Market Leaders .” The ONI Group has an excellent credit rating, is particularly committed to social responsibility, and has held the “Service Champion” distinction since 2025 . The ONI Group pursues a clear goal: to work with its customers to achieve maximum process reliability at the lowest possible production costs and to strengthen their competitiveness in the long term. At the same time, energy-efficient solutions and reduced CO₂ emissions actively contribute to climate protection.