I would like to open up the wall in my garage and install a bookcase type built in to store various items in my wood shop. A small part of the built in would stick out into the air return which is what is on the opposite side of the wall.
My question is would this small intrusion into the air return space cause any problems with air flow to the 3 ton central unit above in the attic? Only about 1 1/2 - 2 inches would protrude into the return air space. My air filter is a 20x25".
My plan is to build the built in out of 1x6 material with a plywood back. Nail and seal all joints with caulk to prevent any air being drawing into the air return. Once installed I will trim the opening and caulk and paint the entire unit. This would help me get a little more organized in a crowded one car garage.
if your not blocking it as it goes back to the unit no problem and or just add another flex connection off the return duct and a wall grill to compensate....pix/drawing might get you so more input....if it is just a wall cavity return you good with the instal l
More likely then not, your return is already under sized. So any thing that protrudes into the return will reduce air flow. Best to add another return to get you the return you should have had. A 20X25 return air filter grille is about what a 2 ton system should have.