understanding hvac... cold air return questions
What size system do you have, what size is the main return/ the existing duct run and what is the size of the remaining return grill?
I ask because you need a minimum amount of return air per ton. It could be that the one you are removing was simply an addition to the minimum, or it could be one part of the two that equals the minimum. You can never have too much return air, you can install return airs all over your house if you wanted from just that one system, but you can have too little.