ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by gfretwell - 03/28/24 12:43 AM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
1 members (Scott35), 276 guests, and 14 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
Joined: Dec 2005
Posts: 152
A
Member
A sparky here at work moonlights doing additional small time resi work. He asked me (I don't know why he picked me, I am just an EE) what the code requirements were for the installation of an outdoor hot-tub. I know there have been posts on this topic (disconnect locations, GFCI requirements etc), please could some of you point them out to me with the relevant code sections if you have them handy.

Stay up to Code with the Latest NEC:


>> 2023 NEC & Related Reference & Exam Prep
2023 NEC & Related Reference & Study Guides

Pass Your Exam the FIRST TIME with the Latest NEC & Exam Prep

>> 2020 NEC & Related Reference & Study Guides
 

Joined: Jan 2005
Posts: 5,445
Likes: 2
Cat Servant
Member
Article 680, which covers pools, has a 'spa and hot tub' section that modifies the pool rules.

It's a good idea that he also check with the local town, as local interpretations - especially regarding whether the ground wire need be insulated - vary. It's possible the town will want an insulated ground wire all the way back to the main panel ... which rules out NMC as a wiring method.

If there's a gazebo over the thing, a ground rod, in addition to the ground wire, is also a good idea. Again, this is a matter of some discussion.

Wires need to be buried deep - preferably 2 ft down. Getting into design issues, I prefer pipe. These steps protect against the gardener damaging them when working on the lawn sprinklers.

Finally, there is the matter of disconnect location. Putting it in the enclosed area that also hides the air conditioner is a common error. An "emergency stop" is not required for residential tubs.

Joined: Jul 2004
Posts: 9,923
Likes: 32
G
Member
680.21(A) pretty much puts you in conduit. You also need GFCI protection. The typical spa setup is a 50a branch circuit with a GFCI breaker and a disconnect box where the spa wires in. Some packaged spas also include a built in disconnect or even GFCI protection so it is good to know what you have before you start. I am not sure how you bond a preexisting concrete deck but by my reading it is still required. You also need to bond all metal within 5' with #8 solid (window frames, screen enclosures, rails, fences and ladders). Most AHJs also want tempered glass in windows near the tub.


Greg Fretwell
Joined: Jan 2005
Posts: 5,445
Likes: 2
Cat Servant
Member
Thank you, Greg, for highlighting some common variations.

I've seen countless variations ... as well as quite a bit of variety in the tubs themselves. The last one I did came with its' own "slab," made of something resembling styrofoam, but looking like cement!

All more reasons to have a chat with the AHJ before work starts ....

Joined: Jul 2004
Posts: 9,923
Likes: 32
G
Member
I suppose that slab is the way around 680.26(C) (3' paved surface bonding.)
Prior to 2005 the bonding of the deck under a spa was not really looked at. I know I did mine way back in 1976 but I was the one who was going to be using it


Greg Fretwell
Joined: Jul 2002
Posts: 717
M
Member
Originally Posted by renosteinke


I've seen countless variations ... as well as quite a bit of variety in the tubs themselves. The last one I did came with its' own "slab," made of something resembling styrofoam, but looking like cement!


Probably made from AAC - autoclaved airated concrete. It is getting more prevalant in building and building materials. Its lightweight and yet fairly sturdy.

Joined: Feb 2002
Posts: 2,233
H
Member
Greg,

Someone mentioned disconnects, and emergency disconnect is not required for resi spas, but a disconnect for the motors is still required to be within 50 feet and within eyesight of the motors, if it is not part of the spa package. As for bonding concrete on existing patios around here some EC's are installing rubber mats around the tubs or wooden decks, this way you are insulated from the concrete.

Joined: Jul 2004
Posts: 9,923
Likes: 32
G
Member
I suppose all these rubber mats and plastic decks are fine ... until they get wet.

The only way to eliminate voltage gradients is with bonding.
That is why we have 680.26 in the first place


Greg Fretwell
Joined: Jul 2004
Posts: 9,923
Likes: 32
G
Member
Mike is that like the Ytong concrete? In any case I would still like to see them put a copper grid in it and a bonding lug.


Greg Fretwell
Joined: Jan 2004
Posts: 1,507
G
Member
Greg- I wonder if a grid is even required around an out door spa if it is above ground. I assume this is the type of spa we are talking about. Maybe it could be a code proposal for the 2011 code? Or maybe an exception?? 680.42 and reference to B kinda tells us what to do with bonding an outdoor spa.

Last edited by George Little; 04/17/08 11:05 PM.

George Little
Page 1 of 2 1 2

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5