i have a 2001 fabia 1.9tdi hatch elegance with an annoying gremlin,there is a loud and intermitant hissing coming from the center vents when i run the aircon,it seems worse at slow speeds/tickover,ive seen many referances to it in posts but nothing explaining what causes/cures this problem,the aircon works but it is only cool not cold and if im stuck in traffic it struggles to get cool,is somthing broke as i had one of those cans put on and it did not seem to need toping up.

this is my first post by the way,this site is fantastic its helped my a few times over the last 12 months.

bograt...

Sounds like it needs to be re-gassed. Take it to someone who knows what they're doing and who can check for leaks.

Hi,

Mine started doing this last summer, I took it to my local dealer who cleaned and re-gased the air con. This stopped the hissing noise and air temp was much cooler. My only problem is that a year later it's started again. So it's worth asking them about leaks while your in.

Mike.

Air con needs to be run at least monthly, to keep the seals properly lubricated.

For the OP, do you keep the centre vents open or closed? I don't get this issue, but I keep them wide open because the full Climatronic system works best with all vents open. You'd get a hissing when it was on full chill and blow with a slightly cracked open vent.

if you air con has never been regassed since new, it's now time to be re gassed and leak tested. You lucky it has lasted this long.

Air con needs to be run at least monthly, to keep the seals properly lubricated.

I think that that relates mainly to the "traditional" design of A/C compressors where there is an elctro-mechanical clutch that only lets the engine turn the compressor shaft during times when the chiller is being demanded. With the system on the Fabia/Polo9N/Ibiza6L plus maybe now some others, the engine turns the compressor shaft 100% of the time - so at least the casing seals are always kept "oiled" - could be as the system operates on a bypass cycle when not required that a small ammount of gas - and so oil, gets passed round the entire system and that should keep all the other seals "oiled". As said elsewhere, no pipework system is completely 100% leak tight, so even with no additional system damage, some of the charge will be lost - maybe someone said as much as 10% per year - originally these systems will have been charged up to a level that will keep them alive for a few years without causing over pressure problems.

i guess its a trip to the aircon man then,thanks for the answers