I had a new complete heat&air unite put in about two year ago I had to go under the house for something and saw the duckwork hanging down and it was about half full of water how can I fix this thanks Arch Lancaster Ky

Leak will have to be located and fixed and duct work is another problem. Leak may be from clogged condensation drain, and needs to be cleared out. There is a couple of good AC guys here and hopefully respond shortly.