Heating system and method for influencing air flows in a heating system

The heating system has at least one first (10) and second heating device (12), and at least one controller. There is at least one flow path between the heating devices, a non-return flap (56) preventing flow from the first to the second heating device and an arrangement for detecting the inhibition of such a flow. An operating state of the second heating device can be controlled or regulated depending on the output signals of the detection arrangement. AN Independent claim is also included for the following: a method of influencing air flows in a heating system.