Hot Tub Wiring Question - Wire Type?

AidanD55

I have read other posts, but they don't seem to directly answer my question. If I missed the correct post, I apologize in advance.

I am building a new house, and am paying to have it pre-wired for a hot tub.

The builder's electrician is considering using 6AWG Romex wire for the interior wiring to an outdoor disconnect. The actual hot tub, and therefore the wiring from the disconnect to the hot tub, are not in place. They will be purchased next year. Most of the models that I'm considering are 240v/50a models. They all say that they recommend a 4 WIRE installation.

My understanding is that the Romex wire is 6/3 with an uninsulated ground. I have seen several threads that say this is not an acceptable wire, but the reason seems to be based upon the wire being used outside. This wire will all be used inside. Am I correct in assuming that this wire is unacceptable because it does not have an insulated ground, and that has an effect on the circuit breaker?

The other option, it seems, is to use THHN wire, but that has to be run in conduits (which I prefer not to have). A conduit will require many 90 degree turns, and the electrician says they'll have to use some kind of jumper box in the middle to split up the cable pulls. Does this seem correct?

So we have Romex 6/3+uninsulated ground, or THHN 4 insulated wires in a conduit, or is there another option? Is there anyone who makes a cable of 6/4 wire that would work in the interior of the house?

I am clear on all the Article 680 requirements, and this question is specifically related to the wiring inside the house.

Thanks!

Search Term: HotTub

Speedy Petey

6/3NM is perfectly acceptable and typical for the INSIDE portion of the wiring to the disconnect.

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Sometimes I feel like if I answer any more questions it is like someone trying to climb over a fence to jump off a bridge and me giving them a boost.

Jim Port

Petey is correct, but some tubs will call for a #6 ground also. The 6-3 NM does not have the #6 ground.

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Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.

AidanD55

Thanks, gentlemen, for the responses.

Maybe I misunderstand, but those sound like differing opinions on each side of the question I'm asking.

Speedy Petey is saying 6/3NM is fine and customary inside the house, and Jim Port saying it's not fine, you need insultated ground.

Yes, let's assume that the tub calls for an insulated ground 4WIRE install.

So that's the heart of my quandry.

Does it make a difference if it's from the breaker to the disconnect, or the disconnect to the tub? I mean, could the electrician use 6/3NM from the breaker to the disconect, and then use THHN (in the future) from the disconnect to the hot tub? Or does it need to be THHN with insulated ground all the way through?

Thanks, and Happy St. Patrick's Day to you!
Aidan

rrolleston

How about running some conduit and pull boxes so the wire can be pulled later when you know for sure what you need.

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Please ask me about my special discount for people that shut up and stay out of my way! With Electricity there is the right way to do it and the dead way. Just because it works does not make it safe.

Jim Port

The unisulated ground on the inside portion is fine. I have installed hot tubs that called for a #6 ground also. This is not available in 6-3NM so individual conductors would be needed.

__________________
Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.

AidanD55

That's a fine idea, and may end up being what we do. But I'd rather not have the conduit, if I can help it.

AidanD55

Great. So the builder can use 6-3NM on the inside wiring, and then THHN (later, on the outside portion to the hot tub) with a #6 ground also.

Yes, again, I am assuming that the hot tub calls for a #6 insulated ground. That is typical on the type of tub that I want, and I assume that's what I need.

Wait, are you saying that individual conductors are needed, even on the inside?

rrolleston

If you are required to run individual wires because the need of a #6 ground then you will need conduit anyways.

__________________
Please ask me about my special discount for people that shut up and stay out of my way! With Electricity there is the right way to do it and the dead way. Just because it works does not make it safe.

Jim Port

If the tub instructions call for a ful sized ground, yes.

__________________
Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.

AidanD55

Thank you, Jim Port and rrolleston (also Speedy Peety).

I understand fully now, and I agree with everything you wrote.

I can now be confident in what I am asking for with the builder's electrician.

Thanks,
Aidan