Hi castremmel,
Welcome to the Heartland Owners Forum and to the family. We have a great bunch of folks here with lots of information and all willing to share their knowledge when needed.
Is this a new unit and have you talked to your dealer? Have you checked the caulking around the top of the window or can you tell where it is leaking.
Be sure and check out our Heartland Owners Club. Join us at a rally when you can and meet lots of the great folks here and make friends for a lifetime.
Enjoy the forum.
Jim M