Abstract: Equipment for the three-stage preheating and degassing of make-up water by means of steam in a power generation installation comprises, in a first stage, a mixing chamber (3) which is located on the outside wall (2) of the condenser of the power generation installation and communicates with the condenser interior via a steam inlet (6) and steam outlet (8). In this mixing chamber, a plurality of water injection means (4) are arranged. A separation column (11) which is located upright underneath the mixing chamber (3) and which is fitted at its upper end with a water distributor (15), forms the second stage. A receiver (21), which is located underneath the separation column (11) and in which steam-dispersing means (22) are fitted and which is connected via a weir (23) to the condenser interior, forms the third stage.