Derek ColeGM, Simmons One Hour Heating & Air · AI HVAC Answers

NEVER Close Your Vents: Why It's a TERRIBLE Idea! #shorts

17 Jun 2026 · 1 min

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0:38

In this YouTube short, HVAC expert Derek Cole warns against closing home vents or installing plastic diverters that force air into the center of a house. He explains that a simple smoke test would show warm air exiting a vent rises to the ceiling and then travels down exterior walls, helping to condition those walls. Redirecting the airflow inward by closing vents prevents this natural conditioning, reducing overall comfort and efficiency. Cole concludes that vents should never be closed and such modifications should be avoided.

Chapters

I would never close off the vents and I would never use the— you go to some houses, you see the little plastic diverters, blows the air in the middle of the house. Again, another bad idea because if you were to do a smoke test in your house, what you would see is when the air comes out of the grill, you would see it go up to the ceiling and then fall down the wall. It's trying to condition that outside wall. So by pushing it to the inside of the room, it's not doing any good. So I would stay away from that and never close your vents. Okay.