This is sort of a continuation of: http://hvac-talk.com/vbb/showthread.php?t=176863
My readings are (with a wet coil):
Stage 1 -- +.34", -.56" (set to 80% of 1200cfm)
Stage 2 -- +.44", -.65" (set to 1200 cfm)
So my return is a bigger issue right now, although I'm guessing increasing the return will lower negative but increase positive static? (I'm also planning on asking them to increase at least 3 of the 6" runs to 7" in the main living areas, so that should help. Enough?)
I've attached a picture of my return. It's an 8"x24" drop, connected to a curved ell, which is also 8"x24". The ell connects to a long trunk, which is 8"x16" on one side, and 8"x10" on the other. All returns feed into this trunk.
My question is...even if I increase the size of the ell and the drop, I'm only getting 8"x26" from the trunk, the way it's connected. I wondering how to increase the flow without having to rip out the trunk and replace it with a larger one. I've heard of using helper ducts on supply runs, can that be done on a return as well? I haven't spoken to my installer yet on the duct changes, I'm hoping to get some ideas of options before I hear from them.