How to Add an Air Conditioning Vent
Do you need to add an air conditioning vent to cool a hot room? This is a project that is not very difficult. Doing it yourself will save you alot of money. Follow these steps to install an extra air conditioning vent.
- Determine what is causing the hot room. If the room has only vents that blow air then you will need to add a return/bypass duct. If you have two vents and one blows air and the other sucks air then add a supply duct. Most older houses do not have air conditioning return ducts in each room.
- Make a material list. All air conditioning flex connections will need duct tape, straps, and mastic. To add a supply duct you will need a 10X6 boot, two 6" flex collars, 6" flex, 10X6 supply grill. To add a return duct you will need two 10X10 boots, two 10" flex collars, 10" flex and a return grill.
- Buy all the materials you need before you start. A home improvement store will have everything you need. Oddly the parts are often in the plumbing department.
- Position the air conditioning boot in the attic above the hot room. If it is a return duct that you are adding then install it near the opposite wall from the existing supply. A supply duct should be positioned to blow into the hot area.
- Cut a hole in the hot rooms ceiling from the attic down into the room. For a return cut the hole 10 1/4 X 10 1/4. For a supply cut the hole 10 1/4 X 6 1/4. The hole should be 12" off the wall and 2" from a truss. The hole needs to be cut from the attic so you know where the trusses are. Move the boot to another wall if needed. A return will need another boot installed as close to the air conditioning unit as possible. Sometimes there is a large one already in the ceiling, if so you can just tap into that.
- Hold the boot in the hole while a helper attaches the grill from below. This will hold the boot in place for now. Screw boot clips or angle to both the boot and trusses.
- Stretch the flex from the vent to either a supply mixing box or to the other return vent. Place a collar on the vent and trace the hole. Cut a hole with a knife. Do the same on both ends of the flex. Install the collars. Make sure to bend the collar tabs over.
- Hook the flex to the vent collar. First push the inner liner over the collar. Use duct tape to secure it in place. Tighten a strap over the inner layer of flex. Pull the outer layer as well as the insulation to the vent. Do not leave a gap. Tighten a strap over the outer layer. Seal the outer layer to the vent with mastic.
- Cut the flex if it is to long. Use a knife to cut both the inner and outer layers. Use wire cutters to cut the wire.
- Hook up the other end of flex the same way as above. Use straps to tie the flex to trusses.