There the steam was fed directly into the feedwater, which thus heated up to boiling point.
The remaining steam was allowed to escape to atmosphere through a second chimney on the tender.
The Rohrbeck system differed in detail from the Kirchweger condenser, in which steam was removed at the blast pipe and led away along the top of the boiler.
The Lower Silesian-Märkisch Railway (Niederschlesisch-Märkische Eisenbahn) put this saving at 7.5% on its locomotives.
Old sources report erosion of the boiler plates which was caused by fatty acids contained in the lubricant accompanying the exhaust steam.