The invention relates to a pressure equalising insert (1) which is provided for installation in a valve (10) for regulating a fluid stream in particular in a HVAC system. The pressure equalising insert (1) comprises a housing (2) having an actuating member (3) which is movably mounted thereon and is configured to at least partially guide the fluid stream regulated by the valve (10) and, when the pressure equalising insert (1) is installed, co-operates with a valve seat (15) depending upon a pressure difference prevailing in the fluid stream in order to regulate the fluid stream. The invention further relates to a valve (10) having an installed pressure equalising insert (1), wherein the pressure equalising insert (1) can be inserted in particular as a pre-assembled assembly into the valve (10).