Sometimes, in the midst of summer or winter, a room can be too cold or too hot relative to the rest of the house. You can prevent the heat or air conditioning from making the temperature too extreme in one area of the house or office by adjusting the ceiling vent. Closing the vent will block all air from coming through, and opening it will allow the air to pass through again; the degree to which the vent is open or shut can be adjusted midway to allow some heat or air conditioning to flow through. This lets you control the temperature in one area without changing the thermostat temperature.
Place a stool or ladder under the vent you want to adjust. Put the ladder or stool in a locked position, if possible, to prevent it from collapsing.
Step up on the ladder or stool until you can comfortably reach the vent.
Locate the dial or switch on the vent. If it is a square or round vent, a dial is usually located in the center. If it is a rectangular vent, a switch is located on either the right or left side of it. On some diffusers, you may have to adjust individual blades manually.
Turn the dial on the square or round vent to the right to open the vent. Turn it to the left to close the vent. If it is a rectangular vent, move the switch up or down to open or close it.