Help with operating pressures and flows in new residential system
I am an aerospace engineer and have some commercial HVAC experience but limited somewhat on residential. I am building a new system for an old house. I will runn 100% flex for the output and some flex for the returns as well.
1. is there a standard operating plentum pressure for residential systems to target?
2. Does anyone have any flow numbers for flex with a foil liner? I know this stuff is more restrictive than galv but I gotta use it on this install.
3. Is there a general rule of thumb for return sizing? ie, return flow = 120% of output?
My over all plan is to create an output plentum in the attic and add start collars as needed to run the 8 registers. Size has not been determined yet but units are 2.5T which is a shade big for the house but the house leaks and will be added on later...