Air Con Specialist North Hertfordshire

[tmwsccsh]

1.    Hi all,
   
   As per the subject, does anyone know of an Air Con specialist in North Hertfordshire?
   
   I need someone who does more than the regas and clean of the system but can actually do some fault diagnostic and repair as well.
   
   As some background, I have had my X for 5 and a half years now and the AC has never worked, apart from for around 2 weeks a couple of years ago when the engine was swapped out.
   
   The revs increase when the AC button is pressed, so I am assuming the condenser / compressor are kicking in, however nothing cold comes through.
   
   I have had a regas in the past but it made no difference and the place that did it advised me to find an AC specialist to diagnose the issue.
   
   The fact that it did work for a short while suggests a leak or similar to me (possibly quite serious!) but I am clearly not an expert and off on a major tangent.
   
   Any pointers to a good place to check it out well received.
   
   Thanks in advance to all.
   
   Regards
   
   TMW