Method for detecting overheating in a heating installation

A method for overheating detection in a heating device, which heating device comprises: a heat source (12), a first sensor arrangement (18) sensing the operating state of the heat source, a heat exchanger region (22) through which fluid to be heated can flow, a second sensor arrangement (34) for temperature detection in the region of a fluid outlet (32), at which fluid outlet (32) fluid that has flowed through the heat exchanger region (22) exits for delivery to a system to be heated, comprises the steps: a) based on a sensor output of the first sensor arrangement (18), determining a first variable characterizing the operating state of the heat source (12), b) based on a sensor output of the second sensor arrangement (34), determining a second variable related to the temperature in the region of the second sensor arrangement, c) when the first variable indicates the presence of a predetermined operating state of the heat source (12), checking whether the second variable lies within a predetermined value range (B), d) when the second variable does not lie within the predetermined value range (B), determining that the heating device (10) is in an overheating state.