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Discussion Forum

Underwater splices

eleeski | Posted in General Discussion on December 28, 2012 11:38am

Our pool has lights that have failed. One light has a bit of wire to work with – but not enough to completely clear the water. The other just has a short stub. The one light with a bit of wire still works. Lights on trips the breaker frequently – but not always. Plus it is an old incandesent that costs a fortune to run. The short one doesn’t work at all.

I would like to either seal off the short one or splice enough cable on to it to replace it with an led pool light. I would like to replace the longer cable light with the led light and a spliced in cable.

Time constraints and cost of water discourage draining the pool. So I need to splice or seal off underwater. Note that the underwater seal off is most critical as the drawdown of the pool for the splice requires  quite a bit less drawdown.

I have replaced many well pumps with splices that have lasted for years in brackish water so I am confident in the security and safety of underwater splices. But all of these splices have been made above water. A Google search turned up links to the splices I have used above water and too many warnings to never ever splice underwater (?).

Any leads to a system that would splice totally underwater would be appreciated. Or at least terminate the short wire. I would also be interested in a low voltage led pool light supplier (maybe a low voltage system wouldn’t trip the breakers if my splices aren’t perfect).

Thanks, Eric

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Replies

  1. DanH | Dec 29, 2012 08:28am | #1

    Unless this is a low-voltage setup, DON'T DO IT.  Even if it is a low voltage setup you need to use caution, as electrocution is not out of the question in the worst-case scenario.

  2. florida | Dec 29, 2012 09:22am | #2

    No splices in pool light wires. You need to run a new wire all the way back to the junction box. You only need to drain th epool to just below the light.

  3. gfretwell | Dec 29, 2012 10:56am | #3

    The LED pool light should come with a cord. Do not try try to splice this. Pool lights are supposed to have conduit all the way back to the J box and pulling in the new one should be easy. Tie a string to the old one when you pull it out to use for pulling in the new cord. Coil up enough cord in the niche to allow working on the light up on the deck before you trim it to size in the J box.

    1. eleeski | Dec 30, 2012 12:02am | #4

      I can't believe that nobody has spliced underwater successfully.

      With that said, the ads that came tailored to this question offered a solution. A battery powered floating light should be the perfect fix for our pool situation.

      However, perhaps I should work on an underwater splice system. There seems to be a real vacuum there. Whether there is enough of a market to make it worthwhile?...

      Eric

      1. gfretwell | Dec 30, 2012 01:55am | #5

        A swimming pool is not a good place to start experimenting. The new light will come with a cord anyway.

      2. DanH | Dec 30, 2012 09:44am | #6

        Yes, they do make equipment for doing underwater splices -- for trans-Atlantic cables, et al.  But the voltages involved are miniscule, and the only creatures in danger of electrocution are fish.

        Do you want to experiment with the lives of your children?

      3. florida | Dec 30, 2012 12:41pm | #7

        No, I doubt there would be any market at all. Code wouldn't allow it and who would take the liability? As Greg said the fix is fairly simple anyway.

        1. eleeski | Dec 31, 2012 12:11am | #9

          I don't understand. "Code

          I don't understand. "Code won't allow it"? Why not? Underwater splices ARE legal. Every well pump has passed inspections with an underwater splice at the pump.

          Safety? I have had broken wires in the well. Either they trip the breaker quickly or the pump won't work. Never have I had a shock from the steel casing of the well or the water around the well. My well driller once got a bit of a shock arc welding in a puddle on the well - but that is entirely different (and he wasn't hurt at all). Low voltage lighting should be even safer. Licking a 9v battery just tickles.

          How does a broken wire in water electrocute a person in a pool? This is not a facetious question. Are there a lot of pool electrocutions? How many levels of failure must be present to cause problems? What are the first line solutions (good grounds, GFI breakers, others?)?

          Obviously, electricity can be dangerous. But we have a long history of safe methods to handle the risks. I would bet that any underwater splice system I would come up with is previously patented and approved.

          Eric

          1. florida | Dec 31, 2012 07:48am | #11

            I think I see now. You didn't come here actually looking for advice but for confirmation of what you want to do or have already done. Why don't you take the advice of electrical  experts here and do it right so you don't kill someone.

          2. DanH | Dec 31, 2012 09:30am | #12

            Underwater splices ARE legal. Every well pump has passed inspections with an underwater splice at the pump.

            I'm guessing you don't let your kids swim in the well.  And the well housing is, kinda by definition, "grounded".

            How does a broken wire in water electrocute a person in a pool?

            The problem is that wet skin has very low resistance, so the voltage required for electrocution is very low.  One would have to get fairly close to the voltage source to be electrocuted, but in medical settings people have been electrocuted with around one volt, so it can happen.

            Probably the worst case would be if someone were holding onto, say, a metal step railing while coming near the (faulty) splice with the other hand.

  4. User avater
    Mongo | Dec 30, 2012 11:25pm | #8

    It's a no-no

    Eric, when you shop for LED lights, you'll see that they come with long lead wires on them, usually 50' or 100' long. That's becuase as the other kids have mentioned, splices are not allowed below water level. Sure, there are splice kits out there. But they are prohibited by code for use with swimming pools.

    All electrical connections for the lights must be made at a certain height above the level of water in the pool, I think code required is a minimum of 12" above water level. Each light should have underground conduit running from the pool light pots to a common area, usually the in the pool pump area. The conduits come up out of the ground usually 2' - 3' or so above soil level, and that is where the electrical connections are made.

    The lights can also be replaced without having to drain the pool. That is IF your new LED light can fit in the existing light pot that is set into the side wall of the pool. That's for gunite pools. I'm not sure about vinyl or fiberglass pools. 

    The light you have now, it should have been set into the sidewall pot with enough free electrical cord to so that you can remove the light housing from the sidewall pot and set the light assembly up on your pool deck. That allows a homeowner to open the water-tight light housing and replace the bulb if need be, all out of the water, without having to disconnect any wiring.

    In your case, if you get an LED light that can fit into your existing light's sidewall pot, then the swap out is pretty simple. All you'll need is a screwdriver and a pull line longer than your conduit.

    1. eleeski | Dec 31, 2012 12:24am | #10

      There is a broken wire in one light without any slack. The other does not have enough play to work above the deck. I'm not sure that the wire can be pulled at all (I'll check). But the easy swap out is not an option. We disconnected the lights at the switch as we were not comfortable with the condition of the wiring. But the lights did function (for several years?) in the damaged condition without electrocuting anybody.

      Some people are requesting pool lights now - that's what is driving the repair. But the floating battery light is too easy - we'll probably go with that.

      Eric

      1. User avater
        Mongo | Jan 01, 2013 09:17pm | #13

        It should be easy if it's in conduit

        If the wire can be pulled:

        You separate the wires wherever the electrical conections are made; at the switch, or in a j-box in your pool pump area, for example. Take a roll of string, mark it every 10' or so. connect the string to the disconnected end of the light's lead wire.

        In the pool: remove the light from the sidewall niche and pull the lead wire into the pool. As the lead wire is pulled, you'll bring the string through the conduit and into the side wall niche.

        Calculate the length of string pulled. Add on several feet so you can store excess wire in the pool wall light niche. Then purchase a light with that length of lead wire.

        Then in the pool, reverse the process. Tie the light's lead wire to the pull string, then go to the switch or j-box or electrical make-up area. Pull the string back out, this will bring the new light's lead wire through the conduit and to the j-box. Make your electrical connections.

        Make sure you coil a few feet of lead wire and install it in the light niche behind the installed light. That way if you ever have to service the light, you can remove the light from the side wall niche, place the light on your pool deck, and service it there instead of having to drain the pool.

        If the wire can't be pulled, they might have direct-buried it. Which obviously should not have been done. In that case, yeah, everything I described is toast.

      2. User avater
        Mongo | Jan 01, 2013 09:18pm | #14

        forgot to add

        Don't forget potting compound.

  5. Amish Electrician | Jan 03, 2013 01:15pm | #15

    Too Smart to Learn?

    That seems to be what we're teaching kids these days. Don't bother researching things, don't bother learning first - you're smart, you can figure it out. It's not rocket science, after all.

    Yea, Sure.

    There are LOTS of pool electrocutions. There have been these problems for decades - both in the 'old days' before GFCI's, and now. With every code cycle the rules get more exacting.

    But, let's not dither with the new and trendy. Instead, let's look at the very first rules. The oldest, most proven rules. These are, simply:

    1) Light wires MUST be long enough to let you set the light on the deck, out of the water, without having to disconnect anything;

    2) Those wires MUST run uninterrupted all the way back to the junction box - no splices, no repairs; and,

    3) Everything has to be in real pipe.

    Then there are the 'other' rules about sealing pipes and bonding the parts

    Does this mean that sometimes you can't repair a light without tearing up the deck? Yes, it does. Too bad.

    It's very simple, really. Do it right or someone WILL die. It's just a question of 'who' and 'when.' 

    Of course, right about now the 'genuses' will chime in with their 'wisdom.' They'll say things like 'no inspector will ever know' or 'MY splices are perfect.' Or, my favorite: "I did it before and it works."  Would you like some cheese with those whines?

    Oh, and by the way ... it IS 'rocket science.' Ever look inside a rocket? There's a lot of wires in there. Rockets were nothing but Chinese party favors until they started putting wire in them.

  6. eleeski | Jan 04, 2013 12:21am | #16

    Thanks to all who have replied. I will certainly have my repairman look for a junction box, conduit from the light and even try Mongo's rope pull trick if the wire is movable. Some of the replies were very discouraging - the pool (and light) is certainly not worth digging up the deck. I posted here looking exactly for ideas which would avoid that outcome.

    Some of the comments were questionable. People claiming death by pool wiring are not realistic. Google search gave results of 60 pool electrocution deaths in 13 years. 13 of those were related to pool lights. Zero pool deaths have been attributed to 12v circuits of any type. That is not a crisis. Using pool rated 12v transformers for lights certainly seems safe. Even with an illegal(?) splice. More people might die from swimming in the dark.

    The advertisers have been very helpful. The poolworld banner advertising offers some great products. Battery powered lights, 12v led lights and edge lights give several options. I wish the underwater splice advertiser was on a banner...

    Regardless, the 120v lights will remain disconnected - for both safety and cost reasons. Eventually we'll come up with a final solution. Thanks again,

    Eric

    1. gfretwell | Jan 04, 2013 12:56am | #17

      If you don't see a box sticking up a foot to 18" above water level on 2 or 3 pipes somewhere around the pool, look on the deck itself for a box under a plate right next to the light. That may not be as much help as you would think because it is supposed to be poured solid with potting compound that you need to dig out.

      Fortunately I have not seen a deck box in years, particularly with low voltage lights. I bet you have a J box (one per light) somewhere near the pool deck or the pump area. If so, give the cord a tug and see if it moves on the other end.

  7. eleeski | Jan 18, 2013 10:43am | #18

    Update on the pool lights: After serious searching, junction boxes were found! My guy was reluctant to pull wires as he had limited time to repair serious damage and no new wire/light assembly to replace with. He was comfortable disconnecting the wires at the junction box for the light with the cut cord and completely severing the cord so the light could be removed and disassembled on dry land. He was able to find a low wattage replacement bulb that sit that style of light - and perfect the assembly process. The other light with the cord in good condition had just enough slack that the light could be carefully disassembled without flooding (he said it was close). We now have one working low wattage light in the pool! It looks great! And has a more comforting safety factor.

    Perhaps in the future we will pull new wire and get LED lights. Thanks for all the input,

    Eric

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