Weird hall light wiring

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I recently moved into a large bungalow which needs a lot of work, which I’m getting through with the generous help of the people on this forum… the latest puzzle is the wiring of the light switches in the long hall, which has three lights in total, all of which come on and off together.


There’s a switch at each end, and one in the middle by the kitchen door. Now any house I’ve ever lived in before, whatever state the lights are in (ie on or off), you reverse it by switching any switch; then you can go to any other switch and reverse it again with that one etc.


However… here it’s different… while, as far as I can see, if the lights are on, flicking ANY switch switches them off, they only come on if they’re up or down in the right combination! I’m going to try and figure out what the working combinations are now, and post – but in the meantime, could this be by design, or is there a fault, do you think?


The house was built in 1994, if that’s relevant.
 
could this be by design, or is there a fault, do you think?
It would seem a very odd thing to deliberately design.

Far more likely that it's like that because it's been fiddled with by someone who didn't know what he was doing but didn't see why his lack of understanding should be a reason for him not to fiddle.

Photos of the wiring would be useful, but really you ought to learn how 2-way and intermediate switches are wired, work out how yours are wrong, and put them right. You don't want to be the next person to go fiddling with them without understanding it.

https://www.diynot.com/wiki/Electrics:Intermediate

http://wiki.diyfaq.org.uk/index.php/2_Way_Switching#Three_Way_.28or_more.21.29_Switching
 
Right, have tested every combination of the three switches - results follows:

For the lights to be on, the following must be true:

1. Switch by front door must be down. AND:
2. EITHER the switch by the kitchen, OR the switch by the bedroom must be down.
3. If both kitchen and bedroom are down, lights stay off, no matter what you do with the front switch.

Make sense of that, if you can...
It would seem a very odd thing to deliberately design.

Far more likely that it's like that because it's been fiddled with by someone who didn't know what he was doing but didn't see why his lack of understanding should be a reason for him not to fiddle.

Photos of the wiring would be useful, but really you ought to learn how 2-way and intermediate switches are wired, work out how yours are wrong, and put them right. You don't want to be the next person to go fiddling with them without understanding it.

https://www.diynot.com/wiki/Electrics:Intermediate

http://wiki.diyfaq.org.uk/index.php/2_Way_Switching#Three_Way_.28or_more.21.29_Switching

Thanks, and you're quite right, of course. I really would like to learn more about house wiring and plumbing. If I wasn't so old, I'd ask somebody to apprentice me... when I have looked at house wiring in the past, one of the problems I've found is that the wiring coming into sockets etc is (a) very short (I guess so it fits in the socket), (b) very stiff (as it's single-core), so it's hard to move it around, twist it etc without breaking the copper.

I know how to use a meter etc (I'm a computer engineer), but it's these physical limitations which tend to flummox me. What do electricians do? I mean, if a wire in a socket breaks, do you have to go up into the attic, pull the whole cable out, and feed a new one back down to the socket??
 
The wiring behind each of the three switches, please.

Okily-dokily... This is the one by the front door, which must be down for the lights to come on:

IMAG1197.jpg


Hope you can see the wires ok... next is the one half way up the hall, by the kitchen door:

IMAG1198.jpg


Finally, the one at the far end of the hall, by the bedroom door:

IMAG1200.jpg


Hope you can make more of that than I can :confused:

**EDIT** Should have said that the left hand (is it "gang" you call them?) portion of the first switch is for an outside light.
 
The switches are the correct type by the looks, but it could be explained by one of the strappers are broken between the first and second switch and second and third switch or a terminal/contact faulty.
It also looks like both cores are connected into the same switched terminal in the first switch. Although not clear so I assume it's just the angle.
Try isolating and testing all the strappers and switch contacts. Especially on the middle switch.
 
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Something not right there. The second switch. Are there a couple more red wires in the back af the box, joined together?
If so, that switch may be the wrong type. It looks like a standard 2-way switch and it should be a special sort called an intermediate.

Edit: and as John says, also the first switch does not look wired right.
The two wires at the bottom shouldn't be together in one terminal.
It's hard to see from those photos.
 
@Taylortwocities agreed it must be something with the second switch but I can't see the extra wires you mention! It all looks spot on to me even down to using 2 reds cable for identifying lives.
My money's on a faulty intermediate switch or loose connection
 
It's hard to see from those photos.

Sorry guys, here we are again - hopefully better this time.

Pic 1 (front door):

IMAG1201.jpg


Middle-of-the-hall switch:

IMAG1203.jpg


Ummm... like Dirty Harry, I know my limitations, and when you guys start using terminology I don't understand, like "strappers" etc, I suspect I may have reached them... time for me to pour more money into this black hole of a house maybe, and get a sparky in?
 
Is the intermediate switch earthed? (not related to your fault, but important anyway)
 
Needs to be earthed as it has a metal face plate. The back box is OK for earthing via the socket if it has a fixed lug but not vice versa. It is still good to earth the switch directly Edit: but you can do it via a flying lead from the back box.
Also the point I made about the connections bring to the wrong terminal of the first switch were correct. The two reds at the top right on the photo should be one at the top right and the other on the terminal next to it.
 
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Now THAT I can understand... although knowing which of all those red wires is which is another thing...
It doesn't matter, all 4 middle ones are pretty much alike. The first and last are correct, assuming your outside light works and doesn't affect the operation of the hall light.
My money is on incorrect wiring at the first switch (proved) and either a broken connecting wire between the second and third or a fault in one of those two switches.
You're going to need a multi meter or continuity tester of some kind and test them, but fix the wiring issue at the first switch first.
 

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