I know multiple people say to close the downstairsregisters, but HVAC sources that I look at say that it greatly stresses the system if you do this and that it's a bad idea.
Haha well true. I just presume that if you have dampers built into the system by an HVAC company that steps would be taken to ensure it doesn't mess up your system.
I've never seen manual dampers that smart. 🤷 Give closing up downstairs a shot and if your evaporator turns into a block of ice, well, then you let it thaw and know your need more air flow.
Haha. Well I don't mean the dampers themselves are smart. I mean that the HVAC companies will do pressure checks make sure things are flowing and vented properly if they are adding in dampers in particular areas.
If you close a register all pipes and joints between the furnace and the register will be under more pressure than designed and can force the joints to cause leaks, this can push humid air into joist spaces as well.
Theres lots of potential issues, putting a damper as near to the source as possible prevents this issue.