Can solid romex cable labelled "indoor" be used since it's enclosed in conduit on a short run? The guy at Lowes said it would be fine. I listened to him but am having second thoughts & I'd like to double check.
What amp rating is on the breaker? This will determine the size wire to use. 12 guage or 14 gage for 15 amp and 12 guage only for 20 amp. make sure you buy THWN white and black for the feeds and insulated green for the ground. NM romex is not rated for wet locations and ALL conduit outdoors is recognized by the NEC as a wet location. Type UF romex is also against code as the ground wire is not insulated. (the UF romex jacket is not rated as an insulator).
THHN stands for "Thermoplastic High Heat Resistant Nylon Coated". The W is for wet location. There are a lot of manufacturers making dual rated THHN THWN wire now. It is usually marked as such. While NM, UF, etc (Romex is a brand name) can be sleeved in conduit for protection, it is not rated to be used there due to the heat rating of the wire. If it is used in conduit, it may have to be de-rated. However, NM cable is not rated for wet applications as UF cable is. Most wire inside a NM jacket is THHN wire. However, you can not remove the jacket and maintain the UL listing for the wire as the wires inside the jacket do not have any labeling on them. I am a bit surprised to the inspectors comment but, seeing he is not an electrical inspector familiar with pool wiring safety,not too surprised. Not following the codes in some cases does not pose too much of a threat to human safety. Not following the codes with pools is not something I am not comfortable with