Electrical Advice Available

[gruvedaddy]

I figured i'd try and help out here in some form , and since i'm not not much of a car mechanic i'd help out with what i know, Electrical. I've been an Electrician for nearly 17 years and have done electrical work in residential, commercial, industrial, institutional and research facilities. So if you got any questions , hit me up and i'll help out if i can.

 

[The_Roadie]

Hiya! I'm an electrical engineer, and do a lot of wiring, but I've never done a portable spa. I've read the advice sites, and know about how GFCIs work. Just not sure about code because the last class I took was in college in 1972. I just bought a used but very nice shape unit.

Going from the CB panel at the front of the house along the inside garage wall to the rear of the house, then through the stucco wall to a GFCI near the spa.

1) With the spa needing 3 #8 AWG conductors for a 40A circuit, and something (12 AWG?) for the ground, is 3/4" EMT the right size for the inside-garage run or do I need 1"? Does it need to be in metal conduit because it's the garage? PVC OK?

2) How long can my flexible run from the wall-mounted GFCI be to the side of the spa? I won't be trenching it because it's right next to the house on a concrete slab.

3) What's with the requirement for a separate 120 V GFCI receptacle near the spa? I have an outdoor GFCI receptacle about 8 feet away, but it's not on the new spa circuit. Does it have to be?

Any other advice? Thanks!

 

[gruvedaddy]

Hey roadie.
1. I'd run a 1" conduit, PVC is fine the entire route. It's much easier to install and cheaper. Also the wires will be much easier to pull in the larger conduit. Use a #10 wire for the ground. And be sure to use a 2 pole 40 amp GFCI breaker for the main feed.

2. The flexable line can be no longer than 6' from the spa, not including the flex line inside the spa that is needed to connect to the junction box. Also, it must be watertight and non metallic , not old fashioned "greenfield". But you'll need to "hardwire" it to the PVC junction box outside, don't use a 40 amp recepticle.

3. As for the 120v plug near the spa, any recepticle outside needs to be GFCI protected and not be closer than 6' , and not farther than 10' from the inside wall of the spa measured horizontally. Also, this recepticle must be independent of the spa circuit.

Only other advice i'd give is to make sure to bond the metal frame to the ground you install. Some older tubs may not have the frame properly grounded.

 

[The_Roadie]

Much appreciated.

1) 1" PVC is cool. I have a 1/2" EMT bender from my college days (put myself through engineering school as a bootleg electrician for my landlord who owned a dozen triple-decker apartment houses), but I thought I might have to get a 3/4" one for this one job. PVC is OK for exposed surface runs even inside a garage? I would have thought it needed to be in metal just for the fire resistance.

2) Watertight conduit is what I was planning for the flex section, and I know about hardwiring. But I thought the GFCI needed to be in the outside box, not back in the main CB panel?

3) Does the outside box need to include a disconnect for emergencies? I found this link:

Spa Disconnect GFCI Load Center, 240V - 30A to 60A

 

[gruvedaddy]

1. Yes, PVC is fine for surface exposure, even in garages. Local codes may require schedule 80 PVC, which is thicker, in exposed areas like a garage. Where i am schedule 40 is acceptable. But if it is to be inspected it's a good idea to check with the local Electrical Inspector for any additional requirments he may have.

2. Yes, the disconnect in that link will work just fine. Again, it cannot be closer than 6' from the inside of the tub wall. In some areas around here it is required for the feed breaker to be GFCI also, as to protect the wires, as short as they may be, that are outide feeding the disconnect. The disconnect is more for the servicing technician to be able to isolate the spa for servicing purposes. I love the tutorials in the link you provided, the women are quite endowed.

Good luck and let me know if you have any additional questions. And by the way, the 4x4 and HVAC on the TB are still working fine. Don't wanna jinx it, but usually the problem would have returned by now. I think we actuallly fixed it roadie! Muchas gracias again!