Automatic ventilating system for water closet bowl units - controls extractor fan by timing switch draws air from bowl for discharge through building stack pipe

摘要

The fan withdraws air from the water closet bowl, to be replaced by fresh air from the immediate environment. Discharge is effected into the existing building stack pipe, or into a separate ventilator duct provided. Connected to the bowl is made by a special additional aperture in its structure. Where the flushing cistern overflow pipe discharges into the bowl, connection may instead be made to the cistern itself, above the waterline, air then being drawn from the bowl via overflow pipe. - The extractor is controlled either by a conventional switch or through a time delay unit which switches off after a predetermined period. The time delay unit and extractor are started by a link with a local lighting circuit.