When your HVAC system blows air into your home, that changes the air pressure inside. The excess air needs somewhere to go, and that spot is the return vent. The return vent is usually bigger than your supply vents because it’s how the air handler sucks air into the HVAC system.

What is the difference between a vent and a return?

You can distinguish which vents are your supply vents because they are the ones you can feel conditioned air being blown out of. Return vents are also covers for the openings in your walls but the difference is that they are connected to your return ducts.

What is the purpose of return air ducts?

Return air ducts draw air out of each room through a separate air vent and convey it back to the central unit to be reheated or cooled. The entire air distribution system is a closed loop, continuously recirculating the same volume of air throughout the house.