Noisy aircon

[swgf]

Following the hot weekend, I used my aircon for the first time in a while and was reminded that there is some constant rattling/noise from under the bonnet somewhere regardless of whether it is on hot or cold, or what temperature. Although it disappears when I use the "Econ" option.

Has anyone got any ideas?? Thanks in advance.

[gazza57]

It may have something to do with the compressor pump if as you described, it disappears when you select econ. when econ is selected the pump is merely rotating but the system is offline so to speak.
If you've not used it for sometime, then you may have a refrigerant leak and the rattling is the empty pump.
The seals can dry out if the air con is left unused for sometime and then the refrigerant leaks away, they usually put a flourescent dye in the refrigerant so a leak can be spotted easily.
Get the system pressure checked and preferably recharged, as the refrigerant is hygroscopic like brake fluid and absorbs moisture from the atmosphere.
Once you have got it sorted it's a good idea to run the aircon all the time, keeps the system up and running OK.
Gazza57

[jill richardson]

You are going to say 'obvious girl thing' now, but my air con made a terrible sound as if the fan was about to come off, even had my mate the mechanic puzzled into believeing it was the motor?? We then noticed that the bonnet release cable had come off its clip on the large air filter inlet (usually damaged when removing to change a bulb) and was catching on the fan, a tie wrap later, all is well, finger crossed its a silly fault like mine.