Hi all,

 

I've had the issue of AC not working at idle since I got my car. After I had it regassed a few years ago, it worked fine as long as I was moving but not at idle.

 

A strange development has occurred though..

 

Last week I took it to a garage to have them investigate the blowing-warm-at-idle issue. They simply (re)-regassed the system, stating that it was 300g of gas lower than it should have been. They told me that this should fix the problem. So, I got in the car and drove to work with the AC on. It didn't work at all - I was fuming (in more ways than one). After work (10pm) I tried it and lo and behold, it worked lovely, and came through nice and cold. I've tried it every day since and it has worked, and it sometimes even works when I'm not moving. 

 

That's the strange thing - that it didn't seem to work at all, then started, and most of all that it seems to work when I'm not moving. It coincides with a noise and engine vibration I hadn't heard before - increased load and a squeaking / whining noise. On investigation this is the smaller rad fan starting up for a few spins, then stopping. Today, I put the AC on, opened the bonnet and prodded the fan, which spun into life, before stopping and starting, always spinning fairly slowly. 

 

Can anyone think of why this may be? does the fan need servicing / repairing? Is it supposed to come on and stay on when stationary?

 

Apart from the re-gas, the only thing I can think of recently that could have affected it is that I had the thermostat and engine temperature control sensor replaced. 

 

if anyone's got any air con knowledge please share!

I'm no expert, but I would suspect that there's a loose connection somewhere and the fan needs cleaning.

Most fans will run with quite low voltage, but have a minimum voltage needed to get them moving, which is higher than their running minimum. Putting the engine under load could divert enough current to stop the fan and the vibration could be messing with a dodgy connection.

The squeaking/whining could be a dirty fan bearing, which would need cleaning if you can or a fan replacement if it's non-servicable.

 

Again no expert, just offering intuition and things that mostly cost nothing to check.

ok, thanks for the advice! I'll see if i can get it out on a nice day and inspect it. I think replacements can be sourced for little expense so I might even try a new one. 

As above, check connections first, but the design of these fans means the bearings can be exposed in certain conditions which eventually start to sieze. If the car has been standing due to lockdown, that may have pushed them closer to the edge. Can you spin the fans - keys out of the car first - by hand?, are they fairly free to move or are they stiff to move?

 

Also, the fan control unit lives directly under the battery, have you had any battery fuming issues down onto that area at all, or water corrosion?.

Edited 3 June, 20206 yr by kentphil1