The Truth About Closing Vents: Does It Save Energy or Damage Your AC?

Many homeowners believe closing air vents in unused rooms can help save energy and lower utility bills. It sounds logical—if you block airflow to specific rooms, your AC won’t have to work as hard, right? Unfortunately, this common myth can cause more harm than good.

Closing vents can reduce efficiency, increase energy costs, and even damage your HVAC system. Let’s examine how your AC works and why closing vents isn’t the money-saving trick many think it is.

How Your AC System Works

Your home’s air conditioning system uses ducts and vents to distribute cooled air evenly throughout the house. The system maintains balanced air pressure to ensure proper airflow. When you close vents, you disrupt this balance, causing unintended consequences.

Why Closing Vents Can Damage Your AC

Increased Pressure in the Ductwork

Your AC system is sized for your home’s total square footage and airflow requirements. Closing vents increases pressure inside the ducts, forcing the system to push air through the remaining open vents harder. This extra strain can lead to premature wear and tear on components like the blower motor and fan.

Reduced Efficiency and Higher Energy Bills

Contrary to popular belief, closing vents doesn’t reduce the amount of work your AC does—it makes it less efficient. When airflow is restricted, your system has to run longer to reach the desired temperature, consuming more energy and leading to higher utility bills.

Frozen Evaporator Coils

When airflow is restricted, the evaporator coils inside your AC unit may not receive enough warm air to function correctly. This can cause condensation to freeze on the coils, reducing cooling performance and increasing the potential for system failure.

Duct Leaks and Damage

Increased air pressure from closed vents can cause weak or aging ductwork to develop leaks. Cooled air escaping into attics, walls, or crawl spaces reduces efficiency and wastes energy.

Uneven Temperature Distribution

Closing vents can create hot and cold spots in your home. Because your system is designed to distribute air evenly, blocking off rooms disrupts the temperature balance, making some areas uncomfortable while others remain too cold or too warm.

What You Should Do Instead

Instead of closing vents, try these energy-saving strategies that won’t damage your AC:

• Adjust Your Thermostat: Raising the thermostat a few degrees in the summer or lowering it in the winter can significantly reduce energy use.

• Regular Maintenance: Keeping your air filters clean and scheduling routine AC maintenance helps your system run efficiently.

• Seal Ductwork: Ensuring your ducts are correctly sealed prevents air leaks and maintains efficiency.

Bottom Line: Keep Your Vents Open

While closing vents might seem like a simple way to save money, it can lead to higher energy costs and expensive AC repairs. The Elite Plumbing, Heating, and Air Conditioning experts can help you find ways to improve efficiency and reduce cooling costs.