Hi: I am currently replacing my old furnance with a new high efficency furnance. When I opened up the wall to expose the old duct work I noticed that their are 2 4" pipes supplying 1 special made boot in the living area. The house is sitting on a concrete slab so there is not much room. My question is can I have the 2 4" pipes go into a 8" oblong or round to elimate the extra space on the plenium. I am not handy with duct work, and the experts I call in can not figure out my problem either. Old house with bad ducts all around. Any help would be greatly appreciated. Thank you
Hi Mr Ed. You mention that the ducts in your house are of poor quality. If they haven't been repaired in a while, it's likely that they're leaking or restricting airflow, thus wasting energy and raising your utility bills. This could cancel out the benefits of your new high-efficiency furnace. It might be a good idea to replace your ducts completely rather than seal them inside of another pipe.