I am in the midst of writing a research paper for school. It's for an English class not an AC class, but I chose to write about ductwork.
My personal opinion is that centralized returns are better for the following reasons. I just need text to quote as this is a research paper and personal opinions are not allowed.
1) It puts the filter in the view of the home owner. It will get changed (maybe) if the nasty thing is staring them in the face and not in the attic through a scuttle hole or buried deep in a small crawlspace.
2) It keeps unfiltered air out of the return duct system.
3) The return can be short and simple reducing the chance for leakage, high static loss or undersizing.
4) The return path stays in the conditioned space longer and is not being pulled back through ductwork in an unconditioned space.
I just need text to quote as this is a research paper and personal opinions are not allowed. I know the disadvantages and found text to quote on that already.
Here is what I have already from ACCA Manual D
A central return is the least expensive system to install. Usually, the return duct is short; consequently, the return side pressure drop is small. This type of return air system occupies a minimum amount of space, is easy to install and is inexpensive. The disadvantages of this system are that each isolated room must be equipped with an air transfer opening (grill or door undercut), equipment noise may not be effectively isolated from the living space and a large return air grille may be unattractive. (ACCA Manual D pg. 1-14)
That should cover opinion 3, just looking for something to cover 1, 2, and 4
Thanks in advance.
(still a student/pro-member)