Fiat Stilo 1.6 2002 Air Conditioning.

My air conditioning is blowing plain air instead of chilled. Anyone know if this is a simple matter of charging something up or whether it is some sort
of more sinister fault?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.