Hot Tub Install

[Oncearugger]

I am installing a 220V hot tub outside, and plan to run 6/3 NM-B wire from the breaker box, up to the attic and across it, then through a concrete block wall to the outside. I'd like to use the appropriate size J-Box (LB) mounted to the outside wall under the soffit and then through 1" SCH 80 conduit to a subpanel mounted to the house. I will need about 70 feet inside the house and 30 feet outside. Is it NEC code to run 6/3 NM-B through conduit, or do I have to splice to THHN?

 

[wyliesdiesels]

I am installing a 220V hot tub outside, and plan to run 6/3 NM-B wire from the breaker box, up to the attic and across it, then through a concrete block wall to the outside. I'd like to use the appropriate size J-Box (LB) mounted to the outside wall under the soffit and then through 1" SCH 80 conduit to a subpanel mounted to the house. I will need about 70 feet inside the house and 30 feet outside. Is it NEC code to run 6/3 NM-B through conduit, or do I have to splice to THHN?

It is code permissible to run NM-b aka Romex, through conduit INDOORS ONLY. You need to transition to THWN in pipe outdoors. Make sure its THWN and not THHN, which is dry locations only. Most THHN is dual rated THWN, however, but check to be sure.

 

[Terry D]

For a pool or spa, You are allowed to use a NM type cable as long as you are inside the dwelling. Once you exit the dwelling, the wiring system must have a insulated EGC. As wylies already mentioned, you will have to use THWN single conductors. You will also need a spa disconnect within sight of the tub, but no closer than 5 feet from the wall of the tub The spa needs to be GFCI protected, the 2-pole GFCI breaker is usually in the spa disconnect,
.

 

[NWOhioChevyGuy]

as stated by Wylies & Terry for the wiring change outdoors.

If you can see the place where wire will exit the house from the spa, put your GFCI spa panel there and NM-B to it and THWN from the breakers to spa.

 

[mike93lx]

When you transition to thhn, make sure you use the proper size box, which is determined by the conduit size. You can look up the formula online.