Asked by: Boujamaa Hymann
asked in category: General Last Updated: 12th January, 2020

How big should my cold air return be?

There typically are as many supply vents as there are rooms in a house. There usually are fewer return vents, but they are much larger. A typical supply vent is 4 by 10 to 12 inches and a typical return vent is 16 by 20 inches or larger.

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Herein, how big should a return air vent be?

Calculate the square root of the total. (Example: 4 (ton unit) x 144 square inches = 576 squared. The square root of 576 is 24. Therefore, your return air duct and grill size will be 24 by 24 inches.)

Also, does every room need a cold air return? DEAR TIM: Ideally you want to have cold air return registers in every room. If you can't easily install a true cold air duct back to the furnace from each room, you can sometimes fake it. You can install a cold air return register above the door from each room that connects to the hallway.

Subsequently, question is, can you have too much cold air return?

While there is no such thing as too much return air for the equipment (actually, there is, and it causes fan cavitation, but very rare), this CAN be an issue for the house. It has the potential to throw off pressures in different areas of the house.

How do you increase return air flow?

3 Simple Ways to Improve Your Furnace's Airflow for More Comfort

  1. Unblock and clean your vents. Here's a super easy way to increase air flow.
  2. Change your filters and clean your return grill. A dirty air filter impedes air movement and makes it hard for your furnace to work efficiently.
  3. Seal leaky ductwork. Snap on some goggles and a dust mask, it's time to check out your air ducts.

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