Central heating boiler fill and drain valve - has slide with radial holes adjacent head communicating with bore

摘要

The valve consists of a body with an attachment thread and sealing ring. The inlet bore is chamfered to form a valve seat which co-operates with the plastic head of a valve slide. The valve slide has radial holes near the head which communicate with the bore. The valve is screwed on to the seat by a nut which is held against a shoulder by a spring ring. The outer end of the valve slide is provided with serrations to provide a grip for a rubber hose. When the valve is open, leakage is prevented by the sealing ring. The nut is prevented from being completely unscrewed by a retaining ring.