Identification and location. Supply vents typically look like small grates and, depending on your HVAC system's design, are located on walls, ceilings, and floors. You can identify supply vents in your home by turning the system fan on and holding a piece of paper in front of the vent.
The Two Types of HVAC Air Vents
Supply vents bring treated air into each room. They warm or cool the room to the desired temperature based on how you set the thermostat. Depending on your system and home's construction, builders place these vents in the ceiling, on the floor, under windows, or on exterior walls.
Your air ducts will be located within the framing of your home. They can be within floors, ceilings, or walls. If your vents are located on the floor, you will find your ducts in the flooring.
The most common problems that cause a lack of airflow include frozen coils, broken fan and restricted airflow due to dirty air filters or vent obstruction. However, there are many other issues that can lead to minimal airflow, so it may be necessary to ask the professionals.
You can identify return vents by turning on the system fan and holding your hand or a piece of paper up. If the paper is pulled toward the vent or you feel a suction effect, it's a return vent.
Supply vents typically look like small grates and, depending on your HVAC system's design, are located on walls, ceilings, and floors. You can identify supply vents in your home by turning the system fan on and holding a piece of paper in front of the vent. If air blows out, it's a supply vent.
You can usually spot return vents on your walls, ceiling, or floors. Look for a white grille without shutters to spot an air return vent. These vents will typically integrate seamlessly into your home.
In AC systems, the air conditioner reset button is on the outside unit's lower edge, typically close to the ground. Some models have the reset button located behind the service panel, which may require tools to remove. Reset buttons are usually red or yellow with a clear “reset” label.
If you can hear your AC running, but the fan isn't kicking on you will want to try lowering the temperature on your thermostat a few degrees. If your fan is still suspiciously quiet, this can be an indication of an issues with the AC blower. The AC blower pushes the cold air out to the ductwork and through your house.
The short answer: Definitely not. (Unless you have manually engaged your outside fan to run constantly, but it shouldn't be running for hours on it's own.) If your HVAC is functioning correctly, it should keep your house cool by cycling on for 15-20 minutes at a time—with distinct pauses in between each cycle.
Visually inspect all ductwork you have access to. Climb into your attic, crawlspace and/or basement and take a look at the ducts that are visible. Look at each section of duct and connection for obvious gaps, disconnections and tears. Also, look for areas of the ducts which have duct tape affixed.
Vents are typically located on the walls, floors, or ceilings of a home and can be opened or closed to regulate the flow of air.
With a smoke stick, incense, or thin piece of toilet paper, hold it up to duct connections/joints to see if the smoke or paper begins to move erratically. You can feel large duct leaks with your hand. Mark the leaking areas with a grease pencil.
If you have central, forced-air HVAC for heating and cooling your home, it relies on a network of ducts that are essential for proper air distribution through the system. The ducts themselves are routed behind the walls, ceilings or floors, so all you see are the HVAC vents that cover the duct openings.
Galvanized steel or aluminum air ducts can be round, oval, or rectangular like the one Bruce Willis crawls through in Die Hard. Sheet metal HVAC ductwork is the most durable and least likely to harbor mold.
When it comes to cooling your home, return vents are best installed near the ceiling so they can draw in any hot air that has risen. Supply vents should also be placed high on the wall for better distribution of cold air throughout the room.
If your air handler is running but not blowing air, there are two likely scenarios: either a broken AC blower belt or an issue with the motor itself.
Signs of an air duct clog include: One room in your house is hotter than all the others. Dirty air coming from vents. Unusual spikes in electric bills.
It's a small, red button usually located on or around the unit. The button should have a clear 'reset' label. Once you find the button, press it for around three seconds and observe the AC. Check whether the AC kicks on immediately and if it doesn't, press the button again for another three seconds.
Obstructed Vent
Furniture, bedding, and the vent damper could all be possible obstacles to the vent. If you find any closed or blocked vents, you can clear away the obstruction and feel for airflow, but if your vents are open and still not blowing enough air, there could be an issue with the fan's motor.
Check the thermostat
You should check if it's been set to the correct temperature and also make sure it's set to “cool”. If the AC settings are not right, it won't turn on. You can also check if the batteries in the thermostat are fresh and replace them if needed.
They are usually located in central, larger rooms to more efficiently pull air from the home and into the system. Return air vents are often located on a wall, rather than the floor or ceiling.
Return vents should be located in centralized rooms, such as larger living spaces or family rooms. These central locations allow return vents to efficiently pull air from the house and into the system. In most cases, you'll find return air vents located on a wall instead of the floor or ceiling.
Reduced efficiency: Your HVAC system will work less efficiently if you block a return air vent. This will make the units use more energy and will raise your utility costs.