Conductor Insulation in Conduit Outside

[czars]

NEC 300.5 states that the insultation on conductors in conduit buried underground must be rated for wet. Good. Eventually water will condense or get in.

NEC 310.8 states that insulation on conductors used in Wet Locations must be rated for wet.

NEC 100 states that a Wet Location is one that is subject to saturation with water or other liquids.

My question is this: If individual conductors are are run in non-metallic conduit on the outside of a dwelling (e.g. to the A/C compressor/condenser unit), where the conduit is subject to being saturated with rain water, must the conductor insulation be rated for wet? That seems to make sense because of possible condensation in the conduit, but only the conduit gets saturated by the rain water. Are the conductors really in a Wet Location?

 

[Pierre C Belarge]

It would make sense that if the raceway or enclosure is installed in a wet location, the conductors in the raceway or enclosure should also be listed for a wet location.

 

[bphgravity]

See 225.4 of the NEC...

 

[thinfool]

Unless carefully sealed, all ug conduit breathes, even non-metallic. Moist, atmospheric air enters the conduit....meets the much lower temperature of the surrounding earth and then condenses on the walls....I am sure there are others here that can tell you, as I can, that condensation can, quite literally, fill an ug conduit completely full of water over a period of time.

In some cases, pvc is worse than grc because it may have no way for the moisture to leak out once it gets in there.

As an aside...what type of insulated wire is commonly sold in the US that is not rated for wet locations.....other than NMC?