Purge, or drain button, to fit Divator breathing valves (336190349/ 336190348/ 336190345/ 336190347) mouth-held and mask versions; with and without positive pressure.

The purge button is used for relieving pressure, when closing down 'negative' (Ambient) pressure SCUBA and for clearing the mask when underwater.

It manually operates the demand lever, causing air to flow through the breathing valve, or mask; at rates not exceeding 2 litres per second and at relative pressure below 45 cm Water column (the safe limit designated (ISO) for airway pressures used for resuscitation, for example). The mechanism is therefore very reliable and safe.

The button may be fitted by users, ensuring that the button moulded is properly secured  in the keyway, which accepts the rubber moulding on to the demand valve housing.

When fitted, test the security, pressing gently with a finger, FROM THE INSIDE of the housing, to make sure it does not detach.  It is first necessary to remove the demand valve housing attachement from the breathing valve body and to carefully remove both the diaphragm sub assembly, which is replaced after fitting.

See image 3, for service instruction excerpt on how to do this.

Please inquire, if uncertain how to do this. Aways function test your re-assembly of components, prior to putting the item back in to service.