Filling vessel for central heating system - has inlet and outlet controlled by rotating plug to provide air pocket and prevent contact between system water and mains water

摘要

A cylindrical vessel (2) has an inlet (13) and an outlet (14) controlled by a rotating plug (11). A pipe (16) from the inlet rises to near the top of the vessel. A drain (8) is controlled by the same plug (11) so that the drain is closed when the inlet and outlet are open. Water from the mains is admitted to the inlet and enters the heating system through theoutlet. When the system is full a pocket of air is compressed in the vessel and separates the system from the mains.