Hi all, 

 

I've got a 22 plate Octavia 1.5 SEL Estate which I'm having problems with the Air-con. I started last week when I kept hearing a hissing sound coming from I think behind the dashboard. It was rather quiet at first so I kind of forgot about it and couldn't really hear it much as it kept coming & going away. This carried on for about 4 days and then suddenly started to get louder and louder kind of sounding like a gas main type hissing. I then tried to investigate it thinking I've got some kind of air-con leak, the air-con itself wasn't as cool as it usually was so I then inspected the condenser - no obvious leaks, looks still brand new, the compressor clicks in & out when you turn the ac on & off but still I get this noise. I then stuck my head down into where the pedals are up under the dash & the sound got louder as if its coming from somewhere behind the dash???? 

 

I was thinking I'd got a leak somewhere but I'm now not convinced as its been 'hissing' for over a week now and surely all the refrigerant would have gone before now as the air-con is always on????

 

Anyone any ideas at all?????

I think the hissing noise does indicate low refrigerant quantity, but it's how the evaporator valve sounds in that situation, rather than the sound of the leak itself.