CONTROL VALVE

摘要

The control valve has a flap valve (13) biassed to an open position by a spring (14). The degree of opening is set by a set screw (15) engaged against a surface (29) on the flap valve (13). Adjustment of the set screw (15) enables control of an air flow therepast. The spring (14) is selected to enable the flap to be closed against a flow of water. The control valve can be applied with a saddle (11) to a cistern pipe (47) to draw odours from a toilet pan (38).