Abstract: The invention has for its object to provide a control unit for the air choke in an oil burning installation which affords good fuel economy and is simple in construction, while being at the same time easy to mount and adjust. The control unit is composed of a piston cylinder (14) the pressure side of which is connected to the pressure side of the fuel pump (22) of the plant in such a manner that its piston (24) performs a working stroke when the pump starts and returns to the starting position when the pump stops. The piston rod (18) of the piston cylinder unit is coupled to a throttle which opens as a result of said working stroke and closes on the return movement.

Abstract: Device for automatic draft control of a furnace having an oil burner, a smoke flue, and an exhaust valve located in the smoke flue, part of said smoke flue comprising a metal tube which is connected with the wall of a chimney, said device comprising a first sensoring device provided on said metal tube and subjected to the influence of the temperature prevailing in said tube, and a second sensoring device provided in said chimney wall, said first and second sensoring devices being connected with the exhaust valve in such a manner that their combined registration is transmitted to the exhaust valve.