Noise when A/C is running

[realh]

My engine (1.6 normally aspirated) sometimes sounds different, making a low whining noise rising with revs, rather as if it had an engine-driven fan, but I'm pretty sure it just has an electric one. The "sometimes" seems to be when the air conditioning is running. Do the compressors usually make a noise like that?

[BenS]

Sounds normal enough to me

[realh]

I don't know, there's definitely something wrong. I'd had it re-gassed a few weeks before my OP; it hadn't been working at all, so after the re-gas I noticed the return of the noise and made the association with the A/C. The mechanic said there was a tiny leak in the condensor which he plugged with no guarantees. Since then it hasn't been blowing as cold as it used to, and once or twice it's failed to work at all. But if it was still leaking surely it would have got rapidly worse until it was off all the time, not go intermittent like this?

[DavidDS3]

Could be that if you had a re-gas following a leak there may not be enough lubricant in the system. I believe that it isn't sufficient to put just refrigerant in the system. I would check with the folks who did the re-gas that they checked the lubricant as well. With regard to intermittent working of the A/C would suggest that the level of refrigerant needs looking at again. It would explain why it isn't blowing as cool as before. If the refrigerant is low then it doesn't activate a pressure switch which in turn activates the compressor. I have known situations where the heat within the engine bay is sometimes sufficient to warm the refrigerant up causing just enough pressure to activate the switch.

[Cake]

I got a whining noise when the AC is on in my ds3. Has been like this since i got it last year and it works good. But might be something to do with to little lubricant for the compressor like David said.

[realh]

Thanks for the replies. Mine has made that noise ever since I got it nearly 3 years ago, so hopefully it isn't too abnormal. I have noticed that the times it wasn't working were when setting off from cold, and then it works a bit later if I restart it with the engine warm, so David could be right on both counts. It did the same today, but even when it was working it was completely inadequate for this heatwave.

[Pepper23]

I came on here to post a similar thing too.
Recently when the aircon is on I hear the engine fan. This can be from as soon as I start my car, even if its been parked in the shade overnight. It stops soon after turning off the aircon.
Aircon works fine and is plenty cold, so I'm not sure if there's a problem or if it's just because it's so hot at the moment?

[Pepper23]

And today the fan was on again, then service light came on with error message 'engine fault, repair needed. In to the garage she goes!

[Pepper23]

And this evening I've returned to my car and the battery is completely flat. I've been into citroen way too many times recently, getting a bit sick of these issues that keep cropping up.

[WeeCamel]

Pepper23.  Did you get to the bottom of the error message "'engine fault, repair needed"?  It has just popped up on my friends car and the fan won't go off either.