With the collapse of the Habsburg monarchy, sales markets disappeared and “the rest of Austria” found itself in a permanent state of economic emergency. But the company survived the difficult war and inter-war years in contrast to manufacturers such as Kafowie, S. Lang and Pongratz & Bock, also based in Vienna.
In the 1950s, the company began to specialize in heating fittings. The familiar sounding slogan „Where there’s heating, there’s HERZ“ also dates from this period. This slogan has long since become obsolete due to the further development of the company. Gebauer & Lehrner attracted media attention in the 1970s with the conversion of the company to Herz Armaturen AG and the employees became shareholders in keeping with the spirit of the times. Employee participation, including group work, brainstorming, group dynamics experiments and seminars, shaped the company’s activities. However, this new form of enterprise did not bring economic success. The Lehrner family had to sell their shares after seventy years as (co-) owners, an investor took over and the employee shareholders gradually returned their shares.