Hiss when aircon first switched on??

[Rickiw]

Had. Regas 9th April 2011... Started using aircon again recently an was fine not as cold as you would expect but did the job and recently when we switch it on you hear the compressor click in and the engine labour but I'm getting a hiss from behind the vents (so it sounds).
Now I checked for gas by quickly pressing in the valve on the pipe and it came out quite forcefully and coated my Allen key in green stuff ( is this die?) so I assume the gas is still there.
I took bumper off and looked at the condenser it has took a beating but can't see no die leaking out... With gas still being in the system Am I looking at a compressor fault?
My opcom read at idle 750kpa when off and went up to 1200kpa when on but sometimes dropping back as low as 900kpa. I'm told it should be up in the 2000kpa area at idle when on.

Any input welcome

Thanks

[Rickiw]

It's a 1.9 120 cdti 07 exclusive

[Rickiw]

Bump

[Big Sig]

The green stuff could also be lube. The hiss is probably just the liquid refrigerant entering the evaporator and gassing off as normal.

[Rickiw]

Thing is it never used to do it and now it's not really cold anymore! I don't wanna just start changing things. Suppose best thing is take it somewhere let them look for a leak.

[LADmachining]

The hiss noise when first turned on is indication of the refrigerant level being low in the system.

It sounds as if a leak detector dye has been added to the system, so that should allow any leaks to be found - of course, the area around the valve you depressed is no covered in dye, so you best tell them you did that or at least give the area a very good clean!

The condenser is favourite for causing leaks due to them rotting out. It only takes a tiny pin-hole to lose refrigerant.

[Rickiw]

Will that stop a condensor leak stop the compressor from pressurising?

[crispy007]

mine does the same had it to local vx dealer £75 and regas later now waiting for a leak to be found so i can get refund and air con repaired under warranty

[Rickiw]

I've writen to kwik fit and complained about the regas I had at Sheffield suggesting they should regas my car im sure they did it wrong it's been pants since they did it. My local kwik fit was spot on.
We shall wait and see.

[Marky]

My opcom read at idle 750kpa when off and went up to 1200kpa when on but sometimes dropping back as low as 900kpa. I'm told it should be up in the 2000kpa area at idle when on.

Since having my aircon regassed by kwik-fit I have had similar hissing.
I always had a suspicion that it wasn;t as cold as it used to be either, but havn't used it much.

Can any one confirm what the kpa should be for the air con as I wouldn't mind checking it myself.