Flexible duct
Flexible duct
(OP)
I've unsuccessfully searched the internet several hours for a supplier of a heavy-duty, 42" diameter, spiral-wire-reinforced, flexible duct for conveying clean ambient air at 5" WC. Does anyone know where I might find such an animal?





RE: Flexible duct
Could you not employ some smaller parallel paths to accomplish this task?
RE: Flexible duct
RE: Flexible duct
http://www.abccanada.ca/
I know they will consider specialty runs.
RE: Flexible duct
Very informative
RE: Flexible duct
Nice study EmeraldCoastHVACR, that one goes in my references folder.
RE: Flexible duct
I have seen the bad results of sloppy flex installations in too many balance reports.
I knew about the high pressure loss, but the paper indicates that my calculations are off by about 10%. All the more reason to limit the use of flex duct.
Excellent paper.
RE: Flexible duct
RE: Flexible duct
The only time flex came close to galv steel was fully extended and there was considerable loses when at 94% efficiency, which is extremely rare (i've never seen it) in the field.
Expect to see flex duct losses approaching 50% compared to galv metal; in addition, expect to see losses using ductboard with liners more than 33% compared to metal(ASHRAE design manual).
From a techs point of view, my experience shows that ductboard & flex systems lower seer ratings 2 to 3 points with all the deteriorating effect that low-airflow systems give(too numerous to mention here).