Air Conditioning - Return Air Grille Size...?

I have a 1636 sg. ft. home with a return grille that's 21" x 26"...there's only one and it's centrally located in my home. My question is this...is the size of the return grille sufficient to cool my house properly...?

And if not, what size should my return grille be...?

Thanks in advance for any help.

The short answer is no but there is far more to cooling your house than the size of the return air grille.

Why don't you start by letting us know what your problem is and giving us some details of where your house is located and the style, type of construction and age of the house. Include as much information as possible concerning the heating and cooling system now installed.

Many factors determine if it's adequate or not. Tonnage of the system and size of ductwork openings behind the grill also have to be accounted for.

Upon reviewing all your previous posts on this subject it appears to me that you have been given some excellent advice. Have you ever done the heat gain calculation?

I have little doubt that you DO have a serious design flaw in your ductwork. The possibility that anyone (or even a group) over the Internet can properly assess your needs and deficiencies are fairly low.

It might help if you kept everything to one topic AND included as much information concerning your system as possible and include as many pictures as possible.