Steam iron having: - a water tank which can be hydraulically connected to a steam chamber via a preliminary chamber, wherein the preliminary chamber may have an inlet opening which is connected to the water tank, and an outlet opening which is connected to the steam chamber; - a drip-protection valve for opening and closing the inlet opening; - a displaceable control rod which extends within the preliminary chamber through a hermetically sealed preliminary chamber through-opening, for adjusting the quantity of water which flows out of the preliminary chamber through the outlet opening to the steam chamber, if the control rod is located at least in a first position (P1a, P1b); wherein the displaceable control rod has a plug part for adjusting the quantity of water which flows from the preliminary chamber through the outlet opening to the steam chamber, if the displaceable control rod is located in a first open position (P1a), wherein the plug part hermetically closes the outlet opening if the displaceable control rod is located in a first closed position (P1b) and is removed from the outlet opening in a second position (P2a, P2b), so that said outlet opening is completely open for the flow of water, characterised in that - the hermetically sealed preliminary chamber through-opening is provided with a ring seal inserted therein which is in contact with the external surface of the displaceable control rod in the first position (P1a, P1b), and - the displaceable control rod has a rod bypass section, which, if the rod is located in a second position (P2a, P2b), the preliminary chamber through-opening hermetically sealed by the ring seal opens and allows a flow of water from the water tank to the preliminary chamber and from the preliminary chamber through the outlet opening to the steam chamber. - a water tank which can be hydraulically connected to a steam chamber via a preliminary chamber, wherein the preliminary chamber may have an inlet opening which is connected to the water tank, and an outlet opening which is connected to the steam chamber; - a drip-protection valve for opening and closing the inlet opening; - a displaceable control rod which extends within the preliminary chamber through a hermetically sealed preliminary chamber through-opening, for adjusting the quantity of water which flows out of the preliminary chamber through the outlet opening to the steam chamber, if the control rod is located at least in a first position (P1a, P1b); wherein the displaceable control rod has a plug part for adjusting the quantity of water which flows from the preliminary chamber through the outlet opening to the steam chamber, if the displaceable control rod is located in a first open position (P1a), wherein the plug part hermetically closes the outlet opening if the displaceable control rod is located in a first closed position (P1b) and is removed from the outlet opening in a second position (P2a, P2b), so that said outlet opening is completely open for the flow of water, characterised in that - the hermetically sealed preliminary chamber through-opening is provided with a ring seal inserted therein which is in contact with the external surface of the displaceable control rod in the first position (P1a, P1b), and - the displaceable control rod has a rod bypass section, which, if the rod is located in a second position (P2a, P2b), the preliminary chamber through-opening hermetically sealed by the ring seal opens and allows a flow of water from the water tank to the preliminary chamber and from the preliminary chamber through the outlet opening to the steam chamber.