I have a 15 year old heat pump. Three years ago the compressor died since it ran out of freon. I had the choice of replacing just the compressor or replacing the whole system. I chose to replace the compressor for $1300. The next 2 years I had to have them come and recharge the freon since everything was freezing up. Cost like $225 each time. Last year I told them to make sure to use the stop leak type to see if that helps. So far so good this year but I just know that a whole new system is in the works just down the road.