Patent ID: 8356724

Claim:
An expansion tank for liquid separated in two chambers of the tank, the tank comprising: a tank body; a filling pipe extending into the tank and forming a passage leading into the tank, the passage including an inlet aperture configured to replenish liquid of the expansion tank; a cover configured such that in a non-fitted state, the cover leaves the passage clear and in a fitted state, the cover closes the passage; a first expansion chamber positioned in the tank and configured to receive liquid which circulates in a first system; a second expansion chamber positioned in the tank and configured to receive liquid which circulates in a second system; the passage divides, at a distance from the inlet aperture, into a first branch which leads liquid to the first expansion chamber and a second branch which leads liquid to the second expansion chamber; wherein the passage divides into the first branch and the second branch at a height level in the tank which corresponds to a maximum level for the liquid in the first expansion chamber and to a maximum level for the liquid in the second expansion chamber; and the cover comprises a closure element configured for closing the first branch and the second branch so as to prevent a movement of the liquid between the first expansion chamber and the second expansion chamber, when the cover is in the fitted state, wherein the closure element is configured to move, responsive to pressure higher than a threshold pressure in the first expansion chamber or in the second expansion chamber, from the fitted state to the non-fitted state so as to allow the movement of the liquid or air between the first expansion chamber and the second expansion chamber.