I'm re-configuring a room and will be moving the register location slightly. Currently, I have two supply ducts that come off the main plenum right next to each other. To gain some headroom in the crawl space, rather than crossing the duct to Room 1 over the duct to Room 2, I'd like to switch the runs so the duct to Room 1 is on the left, inner side. The only reason I can think of that it wasn't done initially was perhaps to gain some room to make a turn up into a vertical stack. With the location of the new register, that's not an issue.
Is it OK to switch the runs or might there be an issue due to the two lines coming off the main plenum right next to each other? I read something recently that suggested that air tends to bypass the second duct if it's too close to the first. I do get air through the register connected to the second takeoff, though I don't have a way to measure flow now that the line is disconnected from the original register location. If there's any concern, I won't switch them because Room 2 is colder because it has three exterior walls and a vaulted ceiling. I don't want to deprive it of heat. The total distance of the two runs is about the same, though one is only horizontal, the other turns up.
Thank you for your advice.
Is it OK to switch the runs or might there be an issue due to the two lines coming off the main plenum right next to each other? I read something recently that suggested that air tends to bypass the second duct if it's too close to the first. I do get air through the register connected to the second takeoff, though I don't have a way to measure flow now that the line is disconnected from the original register location. If there's any concern, I won't switch them because Room 2 is colder because it has three exterior walls and a vaulted ceiling. I don't want to deprive it of heat. The total distance of the two runs is about the same, though one is only horizontal, the other turns up.
Thank you for your advice.