AC discharged completely questions
 

Hey guys,
I had my fans give out on me in my A3 (2007), (replaced and working now) anyways one day i pulled into my driveway and heard a long hissing sound then my ECON light has been on and my ac is not working. i have checked and the system is completely discharged. Is there a valve that would "pop" in such a situation that would bleed off the system if over pressured ? or am i looking at a possible quenched oring somewhere ?

I am in the downtown toronto area and its quite hot without ac and well now my blower fan isnt working either but that a separate situation. just wondering if there is a way i can check the system for leaks without spending a fortune ? I have worked on and built my own cars my whole life but here in Toronto i have no where other than my underground parking to work on it and thats apparently not allowed :P lol ..

any help would be appreciated.

cheers
clet

Re: AC discharged completely questions
 

A hissing sound, quite possibly your compressor

Re: AC discharged completely questions
 

I would be inclined to think so but this happend while idling in my driveway after the fans had failed and once I turned off the car the hissing continued until all of the gas was discharged. Now 0 pressure in the system. Meaning a blown line because of over pressure due to heat and expansion ( unlikely ) or an o-ring quenched out because of pressure ( also unlikely because of the type of seal this o-ring provides but the more likely of the two ) or if there was a valve ie: weak link to discharge the system incase of failure ( smart design ) I'm inclined to think this route but I can't seem to get my hands on a schematic for the system on the 3.2l

Thanks for the input though. Or I'm completely wrong and the compressor seals the bed with the back pressure in the system after the fans fail to cool the charge and pressure spikes.
( I'm a Mechanical eng specialty is Hidraulics and pneumatics)
Just wondering if anyone has had this problem when the famous fan failure has happend ?

Re: AC discharged completely questions
 

Well, the soap and water test has always been the go-to method for finding air leaks of any sort.

Load up the AC system with an air compressor and spray the soap water along the lines and on the compressor.