Building Code and Building Construction - Questions and Answers
Or when you want to know how construction is supposed to be done.

|
AskCodeMan.com
|

Custom Search

AC flex duct in contact with NM wire.

AC flex duct in contact with NM wire.

New postby RICHARD TAN on Mon Feb 23, 2009 3:19 pm

Hi Codeman,

AC aluminum flex duct in contact with NM wire, is this allowed, can aluminum flex duct be energized, is this electrical shock issue if the NM wire has nick or failed.
RICHARD TAN
 
Posts: 60
Joined: Wed Jan 14, 2009 9:43 am

Re: AC flex duct in contact with NM wire.

New postby Jerry Peck - Codeman on Mon Feb 23, 2009 3:49 pm

Hi Richard,

First a question: Are you actually meaning "flexible aluminum duct" used for air ducts such as bathroom exhaust fans and clothes dryer connector duct, or regular flexible duct used for conditioned air, supply and return, which has a plastic outer covering, sometimes metallic looking in color?

If you are referring to actual flexible aluminum duct, then, yes, there is that risk, but no code which addresses it as not being allowed to touch NM cable (with a slight twist, see below).

If you are referring to the regular flexible duct used for conditioned air, then there is only a minimal risk, and still no code which addresses it as not being allowed to touch NM cable (with the same slight twist mentioned above, see below).

The "slight twist" is in "how" the two are in contact. If the NM cable is under the duct (either type of duct) and in contact with the duct, then the NM cable is being used to support the duct, and NM cable is not an approved support for either duct, and in fact NM cable is not an approved support for anything, NM cable in and of itself must be secured and supported by the structure itself.

Hope that helps even though it was not exactly what you were asking.

Codeman
Jerry Peck - CodeMan
AskCodeMan.com
Construction Litigation Consultant - Retired
Construction and Code Consultant - Semi Retired
User avatar
Jerry Peck - Codeman
Site Admin
 
Posts: 1199
Joined: Fri Dec 12, 2008 12:06 pm


Return to Mechanical: Heating and cooling equipment, duct work, ventilation and exhaust fans



Who is online

Users browsing this forum: No registered users and 1 guest