I have a 2004 S-Type with around 34,000 miles on it. I had the A/C united fixed about 7 months ago (it stopped blowing cold so I took it in to get it fixed. Not 100% what it was that they fixed). Well know it only blows cold when I have the temperature set to "low". In other wards if I have it set at 63 it blows warm but when I drop it down 1 degree and it says "low" it blows cold. Anyone have a clue on what is causing this?

I also have an extended warranty through Mercury Auto Insurance does anyone have this insurance and know if this is covered?

Thanks guys.
Russell