On Thu, 19 Jul 2007 17:55:54 -0000, Orlanzo wrote:

I've got a question for you. I live in a two story home
approximately 2400 Sq ft. with a bonus room above the garage. The
heating/cooling equipment is located in the attic. In two weeks, I'm
going to have the first and second stories split into separate HVAC
zones.

An issue I'm facing is the bonus room is either warmer or cooler than
the remainder of the house depending on the season. The HVAC tech
suggested adding a 12x12 return duct in the bonus room; in addition to
a previously existing duct in the upstairs hallway, to help equalize
the temperature. I read the return ducts should equal the total size
of the heating/cooling ducts in the rooms. So, if a second duct were
added in the bonus room, would the existing return duct in the hallway
need to be reduced accordingly?

Any information you can provide would be helpful. Secondary resources
would also be beneficial.

Regards,
Orlanzo

I would NEVER reduce return duct size to any room where I wanted AC.