I am the second owner of a 7 year old home. I have been in and out of my crawl space a lot lately. Every time I go in I have to crawl around my HVAC system. I always thought something was not quite right with the ducting, well I just figured it out. There is a duct that runs from the distribution tunnel to the floor in a part of the interior of the home where there is no register vent. I determined this duct terminates in the subfloor of the front entryway to my home in a corner adjacent to my front door. I have deducted, no pun, that whomever installed the hardwood flooring went right over the duct flange maybe thinking he would cut it in later or something and forgot about it.
There is airflow that is obviously blocked by the hardwood floor covering. I am inclined to cut it in and install a vent, but in reality that part of the house is comfortable without it and that area isnt really a living space. We have to walk by it to go in and out of the front door and my stair case is right there.
I could cut it in and bring air flow to that area which would probably diminish the airflow elsewhere.
I could take down the duct and cap that outlet to the distribution tunnel thereby eleminating any possible heat/cool air loss.
I could leave it alone and pretend I never saw it.