Troubleshooting 3-Way Switches: Why Does My 3-Way Switch Only Work Sometimes?

all right I just put a new three-way  switch in and for some reason   it doesn't work sometimes but it does work  other times why is this happening [Music]   all right so I had a really good question asked  to me this actually happens quite a bit if you're   out in uh you know like putting new devices into a  home and you guys are just kind of ripping through   and somewhere along the line somebody miswired one  of the switches so it's kind of indicative usually   if you have a three-way setup where like one side  doesn't work the other side will so you'll just   flip it into the other position that changes the  nature of power being sent over to this one and   now this one will work but the problem might not  be on this hot side I have my incoming hot then I   have Travelers and then I have a switch leg that  goes up there so hot side is incoming hot switch   leg side is the leg side that goes up to the  light so if you have some of the conductors on   the leg side switched normally you're just going  to notice a problem with the one light source or   like the group of lights that you're working on a  lot of times on the hot side if there's a problem   you'll notice when you switch something on an  entire room will switch on or like multiple rooms   might turn off or turn on it kind of depends on  the situation not always but a lot of times with   the hot sometimes somebody will have wire nutted  something together and then now they're instead   of passing the hot through the box they're using  the device mistakingly they're hooking the hot   up to the device so the connection for the the  rest of the circuit only happens once you flip   the switch into a certain State when you flip it  back if there's no longer a connection through to   the rest of the circuit that's not only a hot side  thing or only a leg side thing I'm just saying a   lot of the times when you realize that when that's  happening when you see multiple rooms I tend to   just go to the hot side first because I know a lot  of times they did something with the hots and then   on a leg side A lot of times it's just this Source  again there's 50 ways to wire stuff and that's not   always the case so you could have one or the other  so how do we go about fixing something like this   so you kind of have to pay attention to what's  happening between the two switches so it's kind of   indicative when you have this side that will not  do anything you know this is the side that there's   a there's a something's being affected too this  is probably not where the problem is it's probably   not being sent power for it to be able to change  States again not always there could be some weird   stuff going on but my feeling about this situation  is that when I go to this side and I all of a   sudden change it now everything works over here  so I'm like okay this seems like it's fine it's   just that when this is sometimes doing something  different it's not okay so my bet is that the   problem is over here so what I'm going to do is  first go turn the breaker off so I can take this   apart look at it see if it's something switched  put it back together and we'll see if it works all right now that the breaker's  off I'm going to go to my leg side   again that's just where I've got a hunch foreign I actually love this little thing because it's  only one speed it's just for taking screws out   it's so light it's tiny I can stick it in my pouch  like uh you don't need this monster drill that   you're carrying with you all the time if I'm not  like drilling into something trying to pop holes   or drill through masonry I don't need a big clunky  drill on me I keep this little thing and I love it   anytime that you take a device out you don't want  to just like rip the thing out you want to look   at it first and be like okay well I know there's  nothing going weird there's nothing like loose   because sometimes loose terminations make things  happen as well and then you slowly when you're   troubleshooting always very slowly pull everything  out it's not because you're going to get   electrocuted I mean you could I guess you should  get shocked maybe but you don't want to change   the state of whatever is happening so you always  want to look around very slowly take everything   out and once you realize okay me messing with  this device is not going to change the problem   or change the state of the problem and now I'm  chasing a ghost then I pull the whole thing out   so what I've got here is I've got one conductor  going on a gold screw and I've got well I've got   a red already on my black so I know that there's  something screwy there a Red's gonna be a traveler   the Red's not going to be a hot or a leg again  could be depends on how somebody wired something   but already that's kind of like suspect so I've  got two black Travelers and a red on my black   screw so I have a three-way switch works is on  the back side of this you can kind of think of   like a flapper in there that's not how it works  internally it's like a it's a different thing   but the way that I conceptualize it is I like to  think that there's a piece of metal going across   here when the switch is in one position and when  I switch that switch into another position the   flapper goes like this and goes boom and connects  these two so all a three-way switch is doing is   just going boom boom boom boom that's why we  call this the common screw because this is the   one that has everything in common so when you  switch it into any state this one is always a   part of the the situation these two are not it's  switching back and forth anyways so another thing   that we can look at is well this is a 14 gauge  conductor it's a lot you know like skinnier these   are 12 gauge conductors so these are probably  in the same 12 3 sheathing and therefore they   should be Travelers so that's my that's what I'm  suspect of the other thing is always look at the   sheathing so back here I've got one black coming  from 1 14 2 and I've got two 12s black and red   that are coming from a 12 three the same sheathing  your Travelers are always going to be in the same   sheeting they should be unless you have some kind  of tricky crazy illegal little three-way dead end   three-way Chicago three-way like weird stuff it  could be weird stuff but if you know that this   house was wired by y'all and it's like present  times and there's nothing weird old 50s wiring   then it's probably that you just got these mixed  up so I know first and foremost okay I've got two   Travelers here my two Travelers should be my gold  screws and my 14 should be the one that goes on my   black screw because that's the switch leg your  switch leg and you're hot on both sides of a   three-way this is your hot side your hot is always  going to be on the black screw on this one and   your switch leg going up to the light is always  going to be on your black side on this this device   so let's just switch these two around pretty  confident that this is going to be the problem I'm   so confident in fact because I actually set this  problem up myself I know this is going to work but I'm gonna act really super surprised for y'all [Music] all right now get it all magically foreign [Music]   ER back on and before this thing did nothing oh man look at  that but what happens when we flip it into the   other state well it still comes on I wasn't doing  that before so now everything works no matter what   if you flip it on you can flip it off here if  you flip it off it actually comes on but then   you flip this one on so you'll also notice with  three-way switches there is no on or off State   it's always changing if you start in one end  of the room and you come in and you the lights   off we'll say and you flip it and you go to the  other side and you flip it off and then you walk   back through notice it's completely changed now  so now when you flip it up it's on when you and   you just keep doing that now it's going to go on  now it's going to go off well not off up but a lot   of people are like wait the switch is upside down  no it's not three ways are always going to change   if you continually go in one side and go back out  the uh the same way then they'll always stay like   the same but once you go in one side and out the  other and then come back around it's going to keep   like changing states which is why none of the  three-way switches say on or off on them like a   single pole switch does there's definitely an off  and definitely an on so that's it hope that helps   you out in the field stop wiring stuff backwards  love you crazy people see in the next one

Channel: Electrician U

Views: 161,226

Keywords: electrician, electrical, electricity, dustin stelzer, electrician vlog, commercial, residential, electrical vlog, electrical courses, electrician courses, electrical class, electrician class, electrician school, 3-way switch troubleshooting, troubleshooting, 3-way switch not working on one side, journeyman electrician, customers questions, electrical contractor, journeyman tips, skilled trades, terms of trade, current affairs today, power issues, troubleshooting 3-way switches

Id: k2yLAFKkzeQ

Length: 8min 59sec (539 seconds)

Published: Wed Dec 28 2022