A heating block half-shell and a heating block for a continuous flow heater, each half-shell including a (partial) wall for a heating channel that includes at least one straight section. In the at least one straight section, at least two guide elements are situated in succession on the wall in the axial direction, each being configured for supporting a heating coil in the heating channel in the radial direction. A continuous flow heater that includes a heating block of this type is also described.