Air conditioning not blowing out cold air on 2007 Chevrolet Uplander

It has been very warm and humid lately. I have noticed while running my A/C on low there is a ticking noise, only on low. Today I noticed that it was not making that noise and blowing out nice cold air! On the way home at the end of the A/C is not blowing out cold air any more!!

Asked by for the 2007 Chevrolet Uplander