Should I Close Doors To Unused Rooms For AC Efficiency?
This question tends to stir up a debate. So many of us have grown up with the impression that keeping bedroom doors closed will trap the cool air in the room, thus cooling the room quicker and longer.
To answer this question properly, first, let’s look at how your AC system works:
Closing Doors To Unused Rooms Creates AC Inefficiency
Your AC system is a central air system designed for whole house cooling based on the foundation of balanced air. To run efficiently, this incredible machine needs balance between the air it takes in and the air it pushes out.
If the intake is blocked because of a closed door, the balance is off, negatively affecting the air flow your system needs to cool your home efficiently. Your system can become damaged, resulting in AC Service.
Should I Close Doors To Unused Rooms Based On Conditions
To answer this question properly, let’s look at 3 scenarios for your home:
- You have one return air grille, typically located in a common area.
- Your home was retrofit with pass through grilles or returns.
- Your home is new, with multiple dedicated return grilles already installed.
Scenario 1: If your home only has one return air grille, the answer to this question is a hard No. Closing the bedroom doors in your home does not cool the room better, save energy, or decrease your monthly electric bill. In fact, it increases your energy expense.
The Inefficiency of Closing Doors To Unused Rooms
When you keep a door closed, the air becomes trapped inside that room, increasing the air pressure.
This positive pressure forces the air to find a way out, i.e., through walls, windows, sliding doors, ceilings, etc.
Simultaneously, the air outside the room is experiencing negative pressure, pulling air in from the walls, attic, windows, doors, and any gaps to the outside to compensate.
Two things now happen.
The imbalance in air causes your home to feel uncomfortable. And, your compressor is working harder to fight this imbalance. This scenario will result in an increase in your electric bill, and potentially AC Service if left alone.
In addition, shutting off interior rooms from air conditioning can decrease the air quality in those rooms.
Since outside air is making its way into your home, allergens and other outdoor pollutants can build up inside. Opening closed-off rooms will create a healthy balance for your system to work efficiently and allow your AC to clear the air.
Scenario 1 basic fix: Keep the door open. Opening the door serves as the air return.
Two Exceptions To Closing Doors To Unused Rooms
Scenario 2: Your home has been retrofit with pass through grilles. These are dedicated air return grilles installed in a specific room (like your bedroom) that solve the issue of pressure balancing between the room and the rest of the home.
Scenario 3: Newer homes built today already have dedicated return grilles installed in specific rooms, as well as common areas.
In scenario 2 and 3, Yes, you can close the door.
In summary, if you have only 1 return grille, keeping your interior doors open will improve the comfort level in your entire house, increase the energy usage of your AC unit so you can avoid AC Replacement, and keep your utility expense down.
Sunset Air and Home Services has been serving SW Florida residents just like you, for nearly 25 years. The foundation of our culture is finding the right solution for you and your family, so you can remain safe and comfortable all year-long.
Contact us to learn more, 239-693-9005