A fluid flow control valve is disclosed. This valve includes a housing which defines a central passageway having fluid inlet and fluid outlet openings. A pressure responsive element is disposed within the passageway for selectively opening and closing the inlet opening to fluid flow in response to fluid pressure exerted thereon at the inlet opening. A mechanism is provided within the passageway for exerting a bias force against the pressure responsive element which is sufficient to close the inlet opening to fluid flow absent a pre-established level of fluid pressure exerted on the pressure responsive element. A fluid filter element is also disposed within the passageway; and a retainer device is positioned for removably securing the filter element within the passageway.