To identify a return vent, take a piece of paper and hold it up to the vent. If the paper is drawn towards the vent, then it's a return vent. Return vents are usually larger than supply vents, and they usually don't have adjustable slats to direct airflow since the air is going into the ducts instead of out.
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.
Because the return air vent works to suck air from a room and back into the ducts, you can try this simple test to see if it is working: take a tissue or thin paper and hold it in front of the return air vent, about 6” away. If the paper is being pulled toward the vent, you know it is doing its main duty.
There is no proper direction for the vanes to point. If they're high sidewall, normally they would be pointed upward which makes them vision proof and just the opposite for low sidewall. Frankly the more open you can leave them the better for system operation. The last thing you would want is to restrict is return air.
Symptoms include weak airflow and uneven cooling or heating throughout your home, with some rooms feeling much cooler or warmer than others. Homeowners should regularly check vents for consistent airflow. If you notice a significant drop in air pressure or uneven temperatures, it could indicate return air issues.
The Secret to Comfort is Balanced Airflow
The current Supply Air vent pressurizes the room, until (in many instances) the pressure inside the room slows the airflow coming from the Supply Air vent! When we install the Return Air vent, the pressure is alleviated. The Return Air vent balances the Supply Air vent.
Hot air rises and cool air sinks. Therefore, opening the right return vents in the summer and winter significantly improves the distribution of air by your forced-air system. You'll also enjoy more even heating and cooling throughout your home. In the summer, open your high returns and close the low ones.
Up High: having an air return higher up on a wall will be better at sucking in hot air that rises. Making it more efficient at transferring this hot air back into your system to repeat the cooling cycle. Down Low: if you have your air return lower on your wall it will function better as a cold air return.
To maintain an even temperature throughout the room, return air vents should ideally be positioned higher on the walls or near the ceiling to capture the rising warm air effectively.
Limited Return Air
You will want to check and ensure that the return vents throughout your vent are not blocked. If these vents are blocked, it can lead to a lack of air being pulled back into your system.
While return vents don't always require filters, adding them provides additional filtration, improving indoor air quality and keeping dirt and debris out of your system.
Instead, there should be at least one return vent in every room, with two or three being ideal. If your house has only one return vent, this is not a problem — make sure to keep the doors open in every room so the air can circulate properly. Make sure there are no furniture, draperies, rugs, etc. blocking return vents.
1. Openings shall not be located less than 10 feet (3048 mm) measured in any direction from an open combustion chamber or draft hood of another appliance located in the same room or space. 2. Return air shall not be taken from a hazardous or insanitary location or a refrigeration room as defined in this code.
Dirty filters, leaky ducts, and poor insulation can cause cold return vents. Leaky ducts often cause cold air to blow even after cranking the heat up. 20-30% of air, especially hot air, is lost because of leaky ducts. Cracked, holey ductwork needs sealing or replacement.
Along with the air your HVAC system pushes through the ducts and vents, the air inside your home can lead to a dusty buildup — especially if your air conditioner recirculates dirt, pet fur, or other debris. This means the exterior cause of your vent's dirty situation may actually come from an interior problem.
If the return duct is too small or there are an inadequate number of return grilles, your HVAC system won't be able to return enough air to recirculate into the system. Again, it's like if you were breathing in through a straw while jogging.
Turn them where you don't look at them and see in. So if they are near the ceiling turn them up. Near the floor turn them down. It really is not going to make a difference in the air flow.
If you prioritize heating, put the HVAC and vents in (or below) the floor. This principle works for return heating vents as well. Place returns for cooling in the ceiling where the warm air congregates and heating returns in or near the floor where the cold air congregates.
If you have a combined heating and cooling system and need to decide between placing the return vents high or low, consider your climate. If you live in cooler climates, it might be wise to install them towards the floor, whereas if you reside in warmer areas, they should ideally be installed close to the ceiling.
While it's best practice to install a thermostat near a return air vent, so that the thermostat senses a homogenous mixture of air sucked from various areas of the home, it's a mistake to have the thermostat located near a supply air vent, where hot or cold air blowing on it can change its reading.
Many central air conditioning systems don't get enough return air. When they don't, you can have all sorts of problems. Hot spots and cold spots throughout your home, indoor air quality problems, premature component failure… It's a long list of really bad stuff.
The filter belongs on the return side of your HVAC's furnace and AC system. It's a “must” to have one there. And if you have a return air filter of the right size that is properly installed, then there is no need for a supply vent filter.
The Size Of Your Return Ducts
If you are installing just one or two return vents, you will want to go with a 12-inch return for 2-ton units and lower. 14- inches for 3 and up. 16-inch should be suitable for 4 ton systems, whereas 5 might require 18-inch returns.
Keep air ducts close to the ceiling: When air ducts are installed near or inside the ceiling, it's usually the most energy-efficient placement. You'll have more even heating and cooling and lower energy consumption.