Why Closing Off Vents & Registers Isn’t a Good Way to Deal with Air Flow

Although this applies to both central air conditioning and heating systems in Las Vegas, let’s use a furnace for example and assume you are trying to get more warm air into a certain room or area of your home.

Problem #1: Closing Only the Supply Register: Many modern heating systems will have one supply vent and one return vent for every room in the home. When closing off a room, many people neglect to close both the supply and return vent, and they only close the supply vent that pushes hot air into the room. The problem here is that the return vent is still sucking cold air into the system. The return vent will pull cold air from the gaps between windows, floors, or outlets and bring it into the furnace to be distributed elsewhere. With the surplus of cold air, the furnace is forced to run for longer periods of time. This wastes energy and therefore, wastes money.

Problem #2: Closing Too Many Registers: Many people still close off all the registers in the home except for one in order to force all of the heated air into the one room that is going to be occupied. The problem here is that your furnace was sized to heat your entire home, and not just one room. The end result is restricted air flow. The furnace is still generating the same amount of heat, but it can distribute it properly. The hot air can’t escape; the furnace may overheat or fail.

Problem #3: Closing Registers without Sealing Ductwork: When you seal off a register in a particular room, it adds more pressure to the air that is still flowing through the system. If you have duct work with leaks and gaps, the hot air generated by the furnace will escape through gaps before it ever reaches the room you are trying to heat. Even with the vent open you were losing heat through these gaps, but not you are losing more because there is extra pressure in the system forcing it out though the gaps. If the un-insulated duct work is located in an area that is not heated, which in turn can drive up heating costs.

Are You Trying to Increase Airflow?

Another reason why people will close off registers is that they want to increase airflow to a particular room or floor of the home instead. But before you run around and start closing vents, it is best to check the vents for obstructions. Many times, the reason a room isn’t getting the best airflow is because there is a couch or chair placed much too close to the vent.

Think you’re still having an air flow problem with your cooling or heating systems? Contact us today and we’d be happy to help you get to the bottom of it!

Categories: Cooling, FurnacePublished On: November 12th, 2021By