Abstract: The invention relates to an insert for an exhaust manifold of a heat exchanger device for a cooking appliance comprising a support for two or more pipe sockets having at least one expansion slit, a first cover for the at least one expansion slit on the support, an insulation comprising a support insulation on the first cover and a pipe socket insulation around at least a portion of the pipe socket, and a second cover at least on the pipe socket insulation. It further relates to an exhaust manifold with such an insert, a heat exchanger device with such an exhaust manifold, and a cooking appliance with such a heat exchanger device.