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I added onto my home and had to wire it myself (except the breaker box) to save money. I have a number of connections inside plastic boxes in the attic where I used wire nuts to connect 3 to 5 14 gauge wires together. Wire nuts keep slipping out by themselves and a light or outlet will stop working. Then I have to climb into attic, track down the box and redo it. It there a better way than wire nuts to keep these wires safely and securely together...something more like the Sharkbite plumbing connectors or maybe a little device on which the incoming power wire could come in one end and be crimped and the other 2 or 3 or 4 wires get crimped into the other end?

Thank you in advance for any help you can provide!

Carlin

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    Sounds like you have a sizing or technique problem. #14 wire is pretty easy to work with if you know the right methods. For 5 conductors, you'll need red size nuts, or multi-size nuts rated for that capacity. Modern nuts don't always require pre-twisting, but you may need to use a plier to finish them off securely.
    – isherwood
    Commented Feb 14, 2016 at 20:07
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    Yes, wire nuts are very reliable and I've never had one fall off spontaneously like that. Something is wrong with how you are using them. When they work right, they bind pretty tight and the wires will not pull out of the nut. They sell a bag with an assortment of sizes, I'd experiment until they work right for you. Then, hate to say, recheck/fix all your past work. Here's some docs on wire nuts idealind.com/media/pdfs/catalog/…
    – Harper - Reinstate Monica
    Commented Feb 15, 2016 at 4:02
  • Yes BUCHANAN makes a crimp-on connector and insulator cap that is very secure, but it requires a special crimper to use.
    – spicetraders
    Commented Dec 19, 2016 at 20:02
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    As @isherwood has stated, the problem isn't the wire nuts, it's something you are doing. Additionally, wire nuts coming loose is a serious, drop whatever you are doing and fix it now issue. Not only would them coming loose pose a short circuit risk, but if it comes loose while supplying an inductive load, that can throw a serious arc, and start a fire.
    – whatsisname
    Commented Sep 13, 2021 at 22:51

7 Answers 7

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You are possibly using the wrong size wirenut for the number and size of wires you are connecting, or simply installing them incorrectly.

"Saving money" is a dubious justification for tackling electrical work if you are not up to the task - the money you "save" can easily cost you a good deal more when your work fails in a more dramatic fashion and burns the house down or injures/kills someone. You could hire an electrician to go over your self-installed wiring and make sure it was correct, and odds are excellent that no more wirenuts would fall off after that.

There are "push-in" wire connector blocks made and listed now. I'm not personally a fan of them, but they are made and listed.

i.e. See this image from Ideal Industries (not endorsing or associated, just using the image as an example)
push-in wire connectors

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    I am a fan of Ideal's push-ins. You can easily verify that the conductor is in far enough, and if, for some reason a wire is shorter than you might like, you can still get the block on easily.
    – Aloysius Defenestrate
    Commented Feb 14, 2016 at 18:51
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    I'm also a fan of the push-ins for DIY usage. They have a strip gauge, can easily be verified, and the wire can twist a bit within the hole without breaking the connection, making it much easier to wire things in gang boxes. They also allow you to re-do everything without cutting the wires if you screw up, and they don't strain the copper conductors. Cost is about 2-3x a wirenut, but that's irrelevant for a DIYer doing a one-off project.
    – gbronner
    Commented Feb 14, 2016 at 20:31
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Personally I like the Wago 222 series lever terminals, they are probably a bit slower to use than a push-in but they make modification easier and they are compatible with both solid/coarse strand installation cable and fine stranded flex.

Note that with spring based connectors (whether push-in or lever style) quality matters, a good quality spring-based contact can be very reliable but there is a lot of unbranded junk around.

Since I wrote my original post Wago introduced a newer series the 221 which support larger wires (they come in two sizes, the 221-4xx support up to 4 mm²/12AWG and the 221-6xx support up to 6 mm²/10AWG) and are physically smaller, but the levers on them are a bit more fragile than on the 222 series.

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  • I just took a look at the Wago web site. It states, This component is only approved in conjunction with mounting adapter (221-501). Does that mean that you have to have the 'mounting adapter' to make it NEC compliant? That seems to be a drawback if you just want to pig tail an outlet and have an on-going cable to the next outlet, too.
    – FreeMan
    Commented Sep 14, 2021 at 17:41
  • I only see that on the special "ex-e applications" variant, not on the regular variant.
    – Peter Green
    Commented Sep 14, 2021 at 20:27
  • Ah. Maybe I didn't realize that "ex-e applications" were special, nor did I know what that actually meant. Thanks!
    – FreeMan
    Commented Sep 14, 2021 at 23:23
  • I think it's something to do with explosive environments but i'm not 100% sure.
    – Peter Green
    Commented Sep 14, 2021 at 23:34
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    This Q just popped to the top again. I must say, I have become a raving fan of Wagos! Well worth the extra up-front cost for the simplicity of wiring & rewiring!! I'm doing my entire home addition with them and (now that I have a big panel for needed new circuits) will be using them for future rewiring and new circuits. Love 'em! (Not affiliated with the company in any way, just a huge fan.)
    – FreeMan
    Commented Aug 11, 2023 at 15:19
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Wire nuts work correctly when used correctly, period. Virtually all professional electricians in North America use them for practically all connections in all junction boxes and device boxes, and use them to the exclusion of any of the other suggestions that have been offered. I have installed many hundreds of them myself.

The package will indicate the number of various sizes that each type of wire nut may is rated for. Most importantly, do NOT simply poke the wires into the nut and then twist it. You must twist the wires together first, with your lineman's pliers or similar tool. If your wires are "slipping out" I suspect you have missed this step.

Soldering (after twisting the wires together!) then wrapping with electrical tape is also acceptable for most codes, and is arguably a superior connection method, but is more trouble than is justified unless using wire nuts would cause you to exceed your allowed box fill (number of wires, connectors, and devices for the volume of the device box in question).

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  • It would sure be nice if people who downvote would have the courtesy to indicate why they did so. It seems to me that that could only help to improve the quality of answers for all of us.
    – user689
    Commented Dec 14, 2016 at 14:08
  • I didn't downvote but citing code or technique for soldering would help. Soldering is easy to do and easy to do properly once you've learned how. To a beginner it is intimidating and possible to do it improperly
    – Freiheit
    Commented Dec 19, 2016 at 16:21
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    @freiheit I completely agree, but soldering also is not a first choice, but merely an alternative that should very rarely be needed. One could argue "Never" needed, unless you did not plan ahead and take box fill requirements into account. It did not occur to me that this might be an appropriate place to offer instructions in soldering, which as you imply requires practice anyway. Code: I have no idea where the OP is located. Since the National Code may be superseded by local variations it's always better for the OP to consult that.
    – user689
    Commented Dec 19, 2016 at 16:38
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I agree with Isherwood's comment in that your wirenuts are probably the wrong size. There are multiple types and sizes. Spend a little more money and get the better nuts.

Next, it's insane that this has happened more than once to you. That should be the sign that it all needs to be fixed up.

It's odd that it hasn't been mentioned yet, but just get wire nuts large enough for the application and then wrap it multiple times round with electrical tape. This will create a better hold.

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    Electrical tape will NOT fix a bad job of installing the wirenut. Nor will it help a properly installed one in any way. It's odd that you would think otherwise.
    – Ecnerwal
    Commented Feb 15, 2016 at 4:46
  • I didn't say it would. It's not a cure-all, nor a solution, but it will hold the wires better than nothing.
    – TFK
    Commented Feb 15, 2016 at 5:07
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    I think arguing over tape has lost site of the issue here, Marr style connecters are very hard to tighten properly when you have an abundance of wires to hold together. I've been prompted to use chanel lock pliers in an effort to make sure they are tight enough to make sure there is a really tight grip on all conductors and no chances of arching within the wire nut. I've seen tape used just to make sure an extra layer of security exists so the Marr style connecter doesn't loosen off!
    – Richard
    Commented Feb 16, 2016 at 16:44
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When purchasing wire nuts be sure to get ones that have a metal coil inside the plastic housing. The metal coil will grip the wire much better and provides a better connection by surrounding the wires with a conductor. Avoid cheap wire nuts that do not have this metal coil insert.

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When you have a lot of wires and Marr type coonecter just aren't doing it, you can always try split bolts. They are a brass bolt with the center cut out in the form of a slot, different sizes. The only hasstle is they have to be taped up good but extremely good when playing with larger wires where marr style connecters are useless to tighten properly.

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    Heatshrink of the proper size can also be used instead of tape.
    – hildred
    Commented Feb 15, 2016 at 2:46
  • I haven't seen any real heat shrinks desiened for this purpose but I suppose even straight ones would work by simple folding over the end before heating I guess. Interesting idea to try though.
    – Richard
    Commented Feb 16, 2016 at 3:01
  • Indeed, Straight sections work fine, although I like to use two sizes, a smaller section that will not fit over the marr will help hold the wires and will add thickness allowing a firmer fit from the larger section, for which I like to cut about three times the length needed, warm one end so it starts to shrink, then fold it in forming a pseudo cup, slide it over the tightened marr and shrink. Works great.
    – hildred
    Commented Feb 16, 2016 at 3:25
  • It sure sounds better than tape, especially the smaller piece before the Marr style connecter to hold all the wries in one place first. This I feel is the hardest part when trying to connect a bunch of wires together with Marr style connecters, keeping them all at the same length to get a tight grip on each. I believe it's Ideal that makes the connecters with the thumb tabs on them to help tighten them properly, one good idea too.
    – Richard
    Commented Feb 16, 2016 at 17:12
  • Could someone define "Marr style connectors" for those who aren't familiar with the term? Note that the preferred technique varies from country to country; wire nuts are ubiquitous and (used properly) trusted in the US, whereas connector blocks are preferred in some other places, and there seem to be religious wars about simple things like whether to twist connectors together before applying the wire nut or not and whether solder is good or bad in this application. In the end, the real determining factor will be the opinions of the Local Authority Having Jurisdiction.
    – keshlam
    Commented Dec 19, 2016 at 16:49
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Binding posts have been used for years, terminal strips are a good choice in many cases as you can get listed ones, but from your brief description, I would use hydraulically applied crimps as they do not fail if done right except in some very esoteric situations like high tension with vibration or moisture with salt (but I have the crimping tool which is not cheap). I have also seen solder, cadweld, brazing and arc welding used successfully. Do not spot weld as it is high resistance and may melt and catch fire. Conductive glue is iffy for any significant current, If you use it you must double check your math for any circuit over half an amp.

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  • Thanks everyone. Looks like I have some more studying to do on my end. Thanks for taking the time to help!
    – Carlin
    Commented Feb 15, 2016 at 19:27
  • In the end if you use the proper sized wire nut, your problem should be solved at the cheapest price. When trying to stuff too many wires into an undersized one, there's never enough room to get a proper grip on all conductors or have them put the right pressure on the center conducters. Try up sizing for safety.
    – Richard
    Commented Feb 16, 2016 at 17:22

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