PDA

View Full Version : How do I use existing ducts to heat/cool the bassement?


Sunil Dixit
Dec 21, 2008, 05:01 PM
I just finished my basement and I want to use current HVAC ducts in the basemet for airconditioning. I have central air and I have some idea as to how I can accomplish that but I have never done this and would appreciate expert technical advice - right from tapping into the source to connecting it to the vent.

Thanks.
Sunil

21boat
Dec 21, 2008, 06:22 PM
Need more detailed information. Are the duct(s) in the actual room of the finished part? Do you know where the air return trunk line is? How many cubic feet to A.C. in finished basement? How is the C.F.M. in the rest of the house when the A.C. is on? Are your trunk lines boxed in and finish drywalled? I am not trying to be difficult to answer your question. I could just say cut a hole in the duct and put in a grill, but that is not a good answer right now. So not to leave you with nothing I Wall say this. Cold air is much harder to push through a house and work right properly than pushing heat. A.C. Its what we call heavy air. It just drops quick to the floor and sits there or falls down the staircases. Keep that in mind when taping into the system and robbing from the trunk line won't won't diminish the performance of rest of the house too much or cause another question to Askmehelpdesk because you were not told or not warned of the possible change that tapping" might effect. I don't know what you system set up is but if there room on the plenum or duct You can cut a round hole 6" hole and use a 6" starting collar to start your A.C. This is like a coupling to start the air run. Now on to to that you can use 6" flex round duct to hook onto the starter collar and run that to you location. If your situation needs more support to hang the new air run use 6"round galv pipe which looks like metal chimney pipe. That also come in flat oval for tight spaces. At the end you get a 'Boot" / which is 6" round in the back of the "boot" and a square opening at the opposite end its all one piece. If you are tapping directly into the trunk line than just do that. NOT the air return trunk line. I hope this helped you enough and gave you some things to think about and you can ask your question with better knowledge and detail. Your big box stores may have all that you need and that will also give you and Idea. Obviously The pluming and heating supply house has it all. Happy Holiday. More Info.