Why You Shouldn’t Close Vents When Air Conditioning Your Home
The standard central air conditioning system in a home distributes air through ducts and into rooms through vents covered with a grill. Most of these grills have shutters behind them that can be moved with a lever to direct the airflow. The shutters can also be closed entirely, and people often think that this is a way to shut off cooling to particular rooms, possibly saving money.
However, this isn’t how air conditioning works. You should never close up vents in your household or do anything else that might obstruct them.
The problem with closed/blocked vents
When a vent is closed off, it doesn’t mean that any less air is being sent to the room. The air conditioner is still operating at the same power level, as is the blower fan. Cool air may not enter the room (or as least only a trickle will be getting through), but the blockage will result in an increase in air pressure within the ventilation system. This is damaging both for the air conditioner and for the ductwork, which can start to develop air leaks. The more closed vents, the more the pressure increases.
Zone control is the answer
If you want to reduce how much energy your AC uses by shutting down cooling to empty rooms, then the method to use isn’t closing vents, but having a zone control system installed. Zone control consist of dampers set into the ventilation system that close off sections of the ventilation system while also communicating through local thermostats to a central thermostat that will reduce energy use from the AC. If you live in a large house, or a house that has a guest room or some other room that is frequently empty, zone control will help considerably at reducing your air conditioning costs. Call for HVAC professionals to ask about zone control installation.