In 1933, Mads Clausen founded Danfoss in his parents' farmhouse in Nordborg, Denmark. His initial products were thermostatic expansion valves, water valves, thermostats, pressure switches & filter driers. In 1952 he entered into a licensing agreement with Tecumseh Products to produce hermetic compressors. In 1956, Danfoss Compressors GmbH was established in Flensburg, Germany as a Danfoss subsidiary. The subsidiary was renamed Secop when it was acquired by German industrial holdings company Aurelius in 2010. Nidec Corp., a Japanese manufacturer of electric motors, acquired Secop in 2017. In 2019, Nidec sold Secop to ESSVP IV, a European private equity firm. Danfoss refrigerant flow controls remain part of the Danfoss Climate Solutions business segment.