Hi,

The aircon in my 2003 S60 2.4 fails when outside temp approaches 30°C.
It works fine for a while, then the compressor shuts down, and delivers warmer air via the vents.
The compressor then kicks in again for a few minutes after being off for 10 minutes or so. --> Typical of expansion valve freeze-up.
In cooler weather it seems fine, maybe because the compressor is called on to run less.

It is probably coincidence, but thinking back it possibly started after I had the windscreen and drivers side (right hand) window replaced. The side window is Volvo, but the windscreen not, and less tinted. I accept that it will allow more heat into the car, but the a/c should handle that?

I am familiar with the older (electromechanincal controlled) systems, but have been out of the refrig game for many years now. Anyhow I have checked all the "traditional" things, compressor comes on, pressures seems OK, condenser fan on, HP pipes and condenser warm, suction pipe cold, then the compessor shuts down.
I am not sure why, the I suspect that the car's computer computer nowadays controls these things, and I do not have access to it.

Can anyone advise an easy way to access the computer and how to determine the cause of this trickery?

Are there common culprits like a thermostat or other sensor that tend to fail? How does one confirm these?
Can it be caused by differentials in teperature, inside, out, engine, dash, coolant, condenser, evaporator, whatever.

I am reluctant to go to the agents, around here they are notorious parts replacers and I cannnot afford to replace a series of good parts.
Preferably I also do not want to follow the same elimination process.

Out of desperation, I have resolved to evacuate the system this weekend, draw a proper vacuum to get rid of any moisture, and re-charge with 1000g fresh (and dry) R134A.

Any experience shared will be highly appreciated.

Kind Regards

Cecil

 

Hi Again,

subsequent to further checking it appears that the ac stays on from cold start, but afer a warm stop after say 20km to fill up, it stopped.

The engine is now warm, and the cooling fan is not running? I think it should, and was not comfortable letting the car idle and haet up more.

From this I would guess that the AC gets disbled because of excessive engine/coolant temp? - and it makes sense.

How can this be confirmed?

Is there possibly a relay that failed, if so, which would be the probable suspects, and how to check.

Thanx & Regards