I just recently found out that my return-air vent is partially blocked. I've been having trouble cooling my upstairs, so I've been looking around to try to find out why. I've been told that my AC is big enough. I took off the vent cover and found that part of the hole is covered by a portion of the wall and even then it looks like they had to build into my bathroom (its on the other side of the wall that has the vent in it). Besides cutting into the wall and making the opening bigger, I was wondering if I could make another return coming from the upstairs. I've always thought that the return should be centrally located anyway. Mine is right behind the front door; there are non upstairs. So basically my question is - can you have two returns going into one blower?

Most homes have returns on every floor and sometimes several per floor. Would it be possible to cut away the blockage? Sounds like that's the easiest fix.

Where is your air handler located? In the basement, first floor or attic? Sometimes it can be difficult installing a return air in the second floor of a house when the air handler is on a lower floors, making it work properly during both cooling and heating cycles can be touchy. When running it as a air condition unit it will work better and be better balanced if you can install a return air in the ceiling of the second floor. Remember heat rises. This can cause you a problem heating your house because the second floor tends to be warmer as well.