You would think that closing vents in unused rooms would save money on heating and cooling costs. It’s less space to cool or heat, correct? Regardless of that logic, it’s a real error that closing vents in unused rooms save energy. Honestly, it can waste more energy than working your unit typically does. Closing vents in unused rooms stop energy from coming into the room. However, it also blows the extra air to other areas in your house.
It doesn’t matter how many vents you open, the AC or heater produces the same amount of air.
The additional pressure from closing a vent produces air leaks in your system, creating unnecessary, long-term energy waste. Air leaks make the unit to work harder as it attempts to make your house comfortable. Additionally, shutting vents could harm your heater or AC, leading to high repair costs.
Does it save money to close vents in unused rooms? The answer is no. It’s better if you keep the vents open to make sure the system functions effectively. This way over the life of your system you can save on energy usage and repairs.
One of the Ways Closing Vents in Unused Rooms Can Work
The primary issue is that closing vents alter what comes out in a specific location. It doesn't alter what the blower is attempting to do. Nor does it adjust the amount of heat the furnace, heat pump, or air conditioner is trying to produce or move.
You might be okay closing a vent or two in your house, but it will be contingent on how leaky and restrictive your duct unit is. If it’s a custom duct system with over 55% higher static pressure than the maximum stated, closing even one vent can put it over the edge. If it’s a well-crafted unit with sealed ducts and low static pressure, you shouldn’t have an issue as long as you don’t close too many.
The only way this can work is if closing a vent made the blower move less air and the furnace, heat pump, or air conditioner produces or runs less heat. Zoned duct units that are accurately designed do this by using variable speed blowers (ECM). If not, you're subject to unplanned consequences, one of them possibly fatal. If you want a Rochester HVAC Technician to check your duct work, contact us today.