Strange aircon noise W126 SEC

[steveb]

I have recently bought a 560 SEC, and notice that with the aircon running I get a peculiar noise - about every 10 secs, there is a noise like sucking air through a pipe for about 1.5 secs. Sounds like it is coming from under dash, but not sure. Is this normal & what causes it?

Thanks for help. I am Merc newbie, 'grown up' from Saab turbo so hope to be able to contribute in due course.

Steve

 

[nickh]

Hi.

Does your aircon blow cold air at all?

I had the same thing on my w124, the aircon was cool, and sometimes cold for a while. I had some aircon specialists come around and regas the system. Now the noise has gone and the aircon is cold again.

I expect you will be running on the old r12 gas which means you will have to have this taken out, then the compressor cleaned then a substitute r143 gas put back in. I know this as it was all explained to me by the aircon man.

N

 

[steveb]

The aircon is functioning - output is quite cool, although I don't know how effective the units should be. The gas is as original R12 - is it a costly job to convert?

Steve

 

[nickh]

I can tell you it will most likely be around £100 all in.

you have to pay for the extraction of the old gas, a clean of the compressor, and the new gas, the process will likely take around 1 hour or a bit more.

As I found out if you have the later r134 gas then a top up is around £60-80

 

[jaymanek]

MB dealer will be about another 150 quid.... but most specialists are very competent as its not rocket science....

 

[steveb]

Ta for help - I will try local independant.

Steve

 

[Badger]

Just out of interest :!:

My dealer quoted £165 to service and re-gas my aircon.

Went down the place down the road that had been recommended and they charged £96 + VAT

what is interesting is that the specialist informed me that Merc don't service Air-Con, they get this speacialist to do it!