National Electrical Installation Standards

Standards as High as Your Own

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Tuesday, September 8, 2020

Question:

Greetings,

I am wiring an AC unit that operates with 20a 230v circuit, I want to run type 12/3 UF cable from the panel at the side of the house to the AC unit at the rear of the house. My question is can I secure the wire to the outside wall under the siding with other wires or will I have to use conduit? 

Allen Hawkins

A

Answer:

Hi Allen,

Type UF Cable is certainly permitted in wet locations, however, it is required to be protected from the direct rays of the sun, unless rated and identified for that exposure, and it should not be used where subject to physical damage. There is very little provided about the suggested installation. See Sections 340.10 and 340.12 for uses permitted and uses not permitted for Type UF Cable.

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