Richards of Hull Ventaxia Darkroom Fans Lightproof Extraction or Intake Ventilation

Can be fitted into a window panel but comes with all the components needed for fitting into a wall up to 14.5" thick. Three speed and reversible for intake when wired to a T Series Controller. Choosing the right size To get 10 Air Changes per Hour (ACH) specify for the following room volume: 800 cubic feet. - Model TX6DR - - 6" unit 1100 cubic feet - Model TX7DR - - 7" unit 1900 cubic feet - Model TX9DR - - 9" unit 3600 cubic feet - Model TX12DR - 12" unit These fans have an internal shutter which closes when the fan is switched off; there is a cheaper Model (TLnDR) without this shutter but this is not recommended because it prevents heat loss and dust blowing in. More recent best practice is for 15 ACH so if space allows always go for a bigger unit which can then be run at a slower (quieter) speed and boosted whenever needed

The air extracted must be replaced so there has to be a light proof grille positioned to allow make-up air to come into the room to create an appropriate air flow movement ... see overleaf