Detach the connection where the flexible duct meets the circular end of the rigid duct.
Moving return air duct.
4 tons x 144 square inches return air duct in square inches.
Return air ducts usually use ceiling joist spaces as the actual duct which then runs back toward the furnace.
A mismatch in return air inlet grille or duct size will reduce the system s effectiveness.
In most cases you can gain several inches of headroom.
A return air duct is what carries air back to the furnace after it is dispensed throughout the home through the supply duct.
This pulls the air across your body.
Forced air heating and cooling systems use ducts to move conditioned air from the furnace heat pump or air conditioner back into the living space inside the house.
Calculate the return duct size based on the air conditioner s size and the type of duct you are using.
Size of air conditioner example.
Sketch out the current duct layout and note the location of each joint.
The air that it s conditioning though isn t just whatever it can get.
Use the following formulas.
If the supply ducts are high or in the ceiling then the return air ducts or grills should be low on a wall.
Without a return air duct the air would not properly circulate and your energy costs would rise.
Measure the existing ducts that are too low.
When you put the ducts in an unconditioned attic and have the minimum insulation allowed you want to move the air at a higher velocity pushing it up near the maximum recommended by acca manual d 900 feet per minute fpm for supply ducts and 700 fpm for return ducts.
The problem is that there is a return air vent in the wall directly under the window that needs to be moved before i can install the door.
Visual inspection for prior attempts to improve return air such as holes cut into an existing return air duct or worse openings cut to admit more makeup air into the air handler from an un conditioned space such as an attic or crawl area.
I am going to be installing a 5 patio door where my dining room window currently is.
If the supply ducts are in the floor then the return air should be located up high.
The return air vent openings need to be on the opposite side of the room so the conditioned air is pulled across the room.
Air handler platforms used as return air plenums can draw air from vented attics and crawlspaces through other connected framing cavities.
You can reroute it or split it into more but smaller ducts.
While none of these spaces makes an acceptable air pathway on its own some building cavities such as floor joists can make acceptable duct chases to contain an insulated air sealed metal or flex supply or return duct.
