Moving junction (deck) box

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C

champishair

0
May 31, 2018
7
southeast pa
Hi all, first time posting but have been using the forums ever since purchasing a house with an old Sylvan pool a few years ago. Finally doing a face lift on the pool and have run into an issue with the pool light that I'm hoping to get some help with.

Situation: concrete decking has been demo'd and is waiting to be re-poured. New tile and coping was also installed and the pool is currently empty. I am taking this opportunity to update the old (non-functional) pool light as well as move the J box as it currently sits in the middle of the decking underneath where the diving board used to be. I purchased a 120v amerlite which I was able to retrofit to the existing stainless steel niche and am now working on extending/moving the J box to a more convenient location.

The Problem: Currently, the rigid metal conduit running from the nich to J box is acting as the means of bonding the niche, which I understand is acceptable. In order to maintain this form of bonding, my understanding is that I will need to extend the conduit with brass conduit. Brass conduit doesn't seem to be carried by normal hardware stores and from what I've seen on line can be quite expensive.
I have seen that another option is to extend the conduit using PVC conduit, but would then need to run bonding wire back to the niche. This would be fine, but my old niche doesn't seem to have a bonding lug that is included on modern light niches.

Questions:
1. Is there any recommendations on where to locate brass conduit and corresponding fittings? I am located in Southeastern PA.
2. Is there a safe/acceptable way to bond an existing wet niche that doesn't already have a bonding lug?
3. Would it be more economical to ditch the 120v light I purchased and go with 12v fixture, transformer, and PVC conduit if bonding cannot be easily achieved?

Thanks in advance for any help/recommendations!
 
Bonding often presents some challenges in pool renovation.

Is this your only pool light? If so then the light connection with the water bonds the water to the bonding grid. You can't eliminate the water bond and maintain proper pool electrical bonding.

Code says "Metal Raceway. Brass or corrosion‑resistant rigid metal conduit approved by the authority having jurisdiction' can be used. So you have an alternative to brass.

If you have access to the skimmer during your renovation you can put the Burndy BWB680AGRK Waterbug Pool Water Bonding Kit in the skimmer can then connect the rod coming out of a hole in the skimmer to the bonding grid. That gives you the water bond and then you can do a low voltage non-bonded light in the pool.

Have you considered replacing the niche with one that has a bonding lug and fits your new pool light?
 
ajw22 said:
Bonding often presents some challenges in pool renovation.

Is this your only pool light? If so then the light connection with the water bonds the water to the bonding grid. You can't eliminate the water bond and maintain proper pool electrical bonding.

Code says "Metal Raceway. Brass or corrosion‑resistant rigid metal conduit approved by the authority having jurisdiction' can be used. So you have an alternative to brass.
...
Have you considered replacing the niche with one that has a bonding lug and fits your new pool light?
Click to expand...

Yes, it is the only light fixture in the pool.

I did see that portion of the code stating "corrosion‑resistant rigid metal conduit" but from researching similar situations, it seemed like the general consensus was that brass should be used, as traditional galvanized conduit would eventually corrode. Are there more accessable non-brass conduit options that I could go with?

I haven't considered replacing the niche as I would expect this to be a significant undertaking that requires excavation, new concrete, etc. Am I wrong?
 
So you probably need an electrical supply store. There are a few in SE Penn so hopefully it’s not to far to the nearest one. You might want to call first if pools aren’t that common for the area. Also, due to the cost it may be a special order.
 
I have not needed to do this so I don't know the specific materials required.

With your deck demoed and I assume you have not yet installed new plaster installing a new light niche is not too invasive. You have to trehcn from the back of the pool by the light niche to the new junction box location. Then some hydraulic cement sealing around a new light niche and plaster over.

@jimmythegreek thoughts?
 
You can get brass from an electrical supply house. The problem is the niche is a wet niche so at some point you have to have a watertight seal to the new conduit. What I have seen done is am unthread to brass threads and then adapt to female PVC and carry that to new location. Then TWO ground rated pipe clamps with solid bond wire brought back to a UL listed light Jbox and wired to the nond lug there. Obviously GFCI protect and the usual. The joint can leak so critical its waterproof. IDK if inspector would sign off but I saw one OK it here in NJ years ago. You also need a second bond plate inside the niche usually with potting compound and that is #8 thwn with a jacket no exposed copper In the water if u wanna be NEC compliant
 
@jimmythegreek
I appreciate the info. Let me make sure I am understanding you correctly. You are saying I could transition the existing brass to PVC conduit and continue the bonding from the brass conduit to junction box via bond wire that is attached to the brass conduit with ground rated pipe clamps?
In this case, what would the purpose of the bonding plate be? Just insurance of additional water bonding on top of what the niche is providing?

As for the transition from brass to PVC, this would be a male thread fitting attached to the existing brass which the female PVC end could thread around? What would provide the waterproof seal here, just typical teflon tape/dope?
 
Yes ptfe paste its thicker than pipe dope like a soft crayon and a few turns of teflon tape first. In a normal wet niche there is a bonding plate that is shared. That plate has a lug on outside for bond wire back to Jbox. Inside it has a terminal for an additional wire. That's the #8 insulated with potting compound that protects from chemical. That wire shares the conduit with the light cord back to Jbox. In the old days a metal niche was enough for inside and outside for metal contact on lug but years ago they started wanting it on any niche. Make sure you use 2 ground rated pipe clamps and 2 separate wires. Not just amy wire a solid #8 copper. Everything is a redundant backup to the other
 
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