The invention relates to a method for operating a hot gas machine comprising at least two cylinders. The upper side of the hot piston is sealingly guided on the cylinder and defines the expansion chamber in a moveable manner. Said expansion chamber is connected to the heater. The lower side of the cold piston varies the compression chamber. The hot expansion chamber of a first cylinder is connected to the compression chamber of a second forward effective cylinder by means of an overflow channel. A heater, a regenerator and a cooler are introduced into said second cylinder. The flow of the gaseous medium is guided in alternating directions and is throttled in the regenerator over the entire flow cross-section and a partial amount of the hot or cold medium is stored. The aim of the invention is to accelerate temperature change and to improve flow conditions. The gaseous medium is throttled or stored in the regenerator (8) in sections which are separated from each other, in the throttle sections (81) and the storage sections (82, 83) which are provided with hollow spaces that are directed in the direction of flow for storing the gas. Said hollow spaces have small cross-sections and predominantly smooth walls.