"A thorough sealing of the duct system, including the furnace cabinet should do a lot to remove pressure differences from the air handler. Radon issues aside, there are a number of reasons to avoid basement returns."
Hi Gregory, Welcome to Home Energy Pros! Feel free to join the conversation in the Forum and Groups. And share your energy efficiency photos, videos and upcoming events. If you're blogging about home performance, this is the place for you!
Let me know if you need help with anything.
Diane, HEPros Moderator