Electrical – Is it okay to use an LFNC whip to connect air conditioner where subject to physical damage

code-complianceconduitelectricalnec

I have seen many air conditioners at ground-level in multiple cities near me that are connected using liquid-tight non-flexible conduit (LFNC) whips.

Example: http://www.southwire.com/products/whip-assemblies-ultra-whip-water-well.htm (Note: this is not an endorsement of the product I selected it as an example because it states: "Commonly used for connecting air conditioners" under applications)

Per 2014 NEC section 356.12(1), LFNC shall not be used where subject to physical damage. As I understand, connecting an air conditioner at ground level on an exterior of a home without any surrounding protection like a fence makes the LFNC very much subject to physical damage (particularly from string trimmers).

Are the installations I have seen in violation of code, or does 2014 NEC section 356.10(1) (listed below) somehow trump 356.12(1)?

356.10 Uses Permitted. LFNC shall be permitted to be used in exposed or concealed locations for the following purposes:

Informational Note: Extreme cold may cause some types of nonmetallic
conduits to become brittle and therefore more susceptible to damage
from physical contact.

(1) Where flexibility is required for installation, operation, or
maintenance.

Best Answer

This would be a decision left up to the inspector, as only they can say what's "subject to physical damage". Though technically, you're correct. Liquid-tight non-flexible conduit should probably not be used in these situations.

It's possible that the units come with the whip factory installed, so the HVAC techs simply install it that way. In my experience, the HVAC community doesn't always follow NEC very closely.