Balanced Air Flow TIps

Published 2010-05-12
In this episode, Dave describes the importance of balanced air flow in a heating and cooling system. Making sure your vents are working properly and preventing leaks in ducts will help save money and energy.

All Comments (21)
  • Dillon M
    To any ac or hvac guys out there , I recently got my ac blower motor changed and this new variable speed blower Blows pretty slow compared to the last one but my house still cooled , I was wondering is it gonna be more efficient or not as good ? For comparison of the old one blew at speed 7/10 the new one blows at 3/10 ( how hard the air comes out all vents )
  • Bryce Taylor
    Hi. I have a 110,000 btu oil furnace with a .85 hp blower. Originally all the intake air was supplied at the blower on the basement floor were there was a 14" by 20" opening for the filter. The furnace had no return duct at all. I had work done by a professional and a 8" x 18" duct was added to extend across the basement and two returns were added to the first floor. The two returns grilles about 6 by 12 inch in size are coming from 7" oval duct off of the larger 8" x 18" duct. My question is: Isn't this going to seriously restrict the return air volume to the furnace and also effect efficiency? I read that 7" duct has a cfm of 150, so total with the two returns is just 300 cfm for the furnace
  • Ulises Pico
    Super useful tips! The music is a little distracting while you’re talking, hope it’s okay to leave that feedback!
  • staggs earl
    Given your choice of a new Ruud Or Goodman heat pump which would you say is the better system overall?
  • Rudolfo Rojas
    Very useful tips and effective presentation, i will try some on my own place that is quite inefficiently constructed.
  • Gidagorfen
    No issue hearing Dave talk with the music in the background. Good tips to start with! I've got one large room not getting the strong furnace airflow for cooling I want, so this was a good start. Thanks Dave!
  • ZERO[F2G]
    First check before sealing duct-work, is to determine if the blower is delivering proper airflow. The simplest check is taking a total external static pressure reading and comparing it to the manufactures fan curve chart. If the duct system is undersized, and that's often the case, then sealing the duct-work makes matters worse.Undersized duct-work= low airflow, sealing undersized duct-work= making duct-work smaller=lowering airflow=more system issues.
  • Hobby Organist
    I have a really hard to duct house, with basement ceilings only about 6' to 6'2" high, and being of a cross tee design, so the floor joists run in opposite directions. I did the best I could but one room is real warm in winter and the others are chillier, the real warm room has a return in it, only one of the others has a return, maybe I need to figure out how to add returns to the other rooms.
  • Anthony Wayne
    Oh, I also want to say that this was an outstanding segment. I learned a truck load! cheers!
  • tyson sittu
    The intro was an overkill but the tutorial made up for it. Thank you sir and have it a thumbs up! Great vid
  • Luba Luba
    Could increase airflow of cold air in other rooms by closing vents from rooms I don't care to cool. Because my central air system is on continuesly.
  • Maayong Aga
    Very informative...you're the only one that make sense.
  • Ruminator
    Mars is the best HVAC teacher out there that I've seen.
  • Duh, code violation of CSST passing into furnace. This is against code because the all furnaces have some normal violation movement and the CSST can easily flex down to be cut by the moving sharp edges of sheet metal. Only Black Iron Pipe should pass through the walls of the furnace cabinet.
  • My thermostat is located in the furthest (away from the furnace) room in the house, It gets the least amount of air flow and the central air is constantly ON because the room takes forever to cool?, Should I close off other rooms to increase the air flow?
  • Lvvry1
    I have a finished basement apartment. Can I redirect the cold air INTO the return system before the filter in the furnace?
  • tstatech
    Call a contractor that specifically states that they deal with air distribution problems.
  • Andyyy
    Is this only for single zone HVAC?