Problem with Contactor on Bryant 561CJ036-E

blower motor not turning on.

I had a house built and closed on March 1st, 2002. I have had no problems with the heat pump until about 3 days ago when it stopped cooling my house. The fans are blowing and everything is kicking on, it just isn't blowing out cool air. I notified the builder who sent me to the company that installed my heat pump. They stated that I had obviously used all my freon and it was not covered under warranty after the year was up. I told them that I didn't feel it was possible that I used all of the freon as I only run the a/c about 2 months a year. She told me it didn't matter and that because it is a heat pump it runs freon year round. I still don't think that in 15 months, considering that I run a/c for 2 months and heat for maybe 5 months, I have used up all of the freon. I have been told by others that they have had a problem when their house was built in the winter that they can't completely fill it with freon. My question is, How long does freon usually last? Does your heat pump run off of freon in the winter? Is this something worth fighting them about or am I better off just eating the cost? Thank you so much for your help.