Specifications
selected level.  In this case, the extractor continues to operate for the selected period 
set on the timer after the switch light has been switched off. 
ATTENTION:  When  the  humidity  rate  is  above  the  selected  value,  the 
automatic option takes precedence over the manual and the unit cannot then 
be switched off using a switch. 
The desired humidity level is selected by means of a potentiometer “% Hr” positioned on 
the printed circuit board (fig.10) and accessible once the grille (1) has been removed. 
  - To increase the humidity setting turn anticlockwise (min.60 %) 
  - To reduce the humidity setting turn clockwise (max. 90 %) 
To set the timer, turn the potentiometer “t min.” on the printed circuit board (fig.10): 
  - To reduce the "run on" time, turn anticlockwise (min. 2 minutes) 
  - To increase the "run on" time, turn clockwise (max: 20 minutes). 
SILENT-100 PIR (this version is only available as SILENT-100) 
Models  provided  with  a PIR (passive infra-red) detector. The unit starts automatically 
when a movement is detected with a maximum distance of 4 metres (fig.9). 
They are also fitted with an adjustable "run on" timer (1 to 30 minutes), and the unit will 
continue to operate for the set period after initiation by the movement detector. 
To set the temporisation, turn the potentiometer on the printed board (fig.7): 
  - To reduce the "run on" time, turn anticlockwise (min. 1 minute) 
  - To increase the "run on" time, turn clockwise (max: 30 minutes). 
SILENT-150 P and  HTP (these versions are only available as 
SILENT-150) 
Models provided with on/off pullcord switch use the following wiring diagram: 
Fig.11 – SILENT operated only with the pullcord 
Maintenance 
The extractor fan only requires periodical cleaning using a cloth lightly impregnated with 
a soft detergent. 
After Sales Service 
We recommend you do not dismantle or remove any other parts than those mentioned, 
as  any  tampering  would  automatically  cancel  the  guarantee.  If  you  detect  any  fault, 
contact your EnviroVent on 01423 810810. 
EnviroVent reserves the right to alter specifications without notice. 
All EnviroVent products are designed to be recycled when they reach the end of their 
working life. To save the environment and to reduce landfill, please call EnviroVent on 
01423 810810 to arrange for the fan to be returned to the factory. 
EnviroVent Ltd 
Envirovent House 
Hornbeam Business Park 
Harrogate 
HG2 8PA 










