hmm beenthere do we need to know the distance of the 12" from the plenum
to determine if we needed two 8" vents for one room? because if i understand correctly an 8" vent will give you more pressure but less volume. meaning the air of one 8 " vent will arrive fast but will not cool the room fast enough so if we needed to cool down this room quick enough because it is a long run from the plenum we would need two 8" vents on 8" flex duct to be able to get the volume the room requires ? so it can receive the air on time and cool it on time before the unit shuts down? am i correct, I'm not a pro but if this guy didn't do something right i need to know. i understand that visual is a big roll in this but the windows also play a roll and this room has 5 tall windows. beenthere if you'd like me to pm you let me know.
thank you for helping understand this allot more. i need to be more prepared for the next unit. i always find forums too late to do some homework before i pay someone for something. live and learn. i didn't think i would find such a forum for hvac wish i had searched before i hired someone to the job .