Air conditioning on 1999 Volvo S70

AC on 72 degrees is blowing out hot air but if on 62 degrees it gets cold right away. Also the recirculation button and the AC button both turn on for approx. 20 seconds before turning off. What could be wrong?

1 answer 1 comment
If the A/C lights are flashing when you turn on the vehicle then you have a fault recorded in the climate control module that needs to be diagnosed. If the lights aren't flashing, I would have the refrigerant system checked, it may be low.
I don't quite understand the last part of your question: "Also the recirculation button and the AC button both turn on for approx. 20 seconds before turning off. What could be wrong?" can you elaborate?
I took it to the Volvo dealer and they say its's the ECC temperature sensor. They want $223. for the part plus $6250 for installation plus tax. Is this reasonable?