Replacing dimmer switch with new metal switch.

[AJ2014]

Hi Guys,

Before I start, I've already tried searching the forum for an answer to my problem but i'm still confused.

I've basically moved into a house and want to replace all the plastic light switches with metal ones.

I thought i'd start in the living room but i've run into a problem.

Basically the switch i'm replacing in the living room is a dimmer, in addition to this there is a 2 button switch in the hallway which also controls the living room lights aswell as the stairway lights but, there seems to be a problem with this setup because if I switch the living room lights off with the hallway switch I can no longer use the switch in the living room, it is somehow disabled, I have to switch on again before I can use the living room switch again. I'm assuming its been wired wrong.

I've unscrewed the dimmer and found it had 2 red wires twisted together going into L1 and the black going into C. The new metal switch i'm replacing with has C, L1 and L2 and an earth point. I've managed to get it working but the issue with the hallway switch is still there. I've tried using different wiring combinations but the problem is still there. I haven't had a look at the hallway switch yet.

I'm not too bothered about having the hallway switch for the living room, it would be useful but if its going to cause problems then I would rather just have the one switch for the living room lights.

Am I correct in assuming that one of the red wires links the 2 switches together?

Can someone please advise how I would wire the new switch correctly.

Thanks

 

[AndyPRK]

Give us pics or a description of the hall switch

 

[ban-all-sheds]

It doesn't really matter how much dancing around we all do here - basically you've got a choice of Plan A or Plan B:

PLAN A:

• Learn how lighting circuits are wired.
• Get a multimeter and learn how to use it.
• Identify which conductors are which at the switches and the light positions.
• Check for voltage present, circuit continuity, switches working etc.
• Connect everything up properly.

PLAN B:

• Get an electrician.

 

[tommo2]

You will not be able to have normal 2-way switching unless you can run a new wire between both switches.
It appears both switches are wired "in series". So both have to be on in order for the light to work. Turning either one off will prevent the light coming on regardless of what the other switch does.
I would do away withe the hall switch. Change it to a single switch for the stairway lights, join the 3 wires for the living room together.

Now this is very important... make sure you earth the metal switch. If there is no earth wire in the switch box then you need to run a new earth wire (1.5mm) or else you cant have a metal switch.

 

[AndyPRK]

You will not be able to have normal 2-way switching unless you can run a new wire between both switches.

I don't think we can say that for certain.

There appears to be 2 wires coming into this switch.
There are no reports of other lights being prevented from working in the house.
It's possible the 2nd wire is a strapper and both switches are incorrectly wired.

Knowing what's going on in the hall switch is key

 

[tommo2]

I don't think we can say that for certain.

There appears to be 2 wires coming into this switch.

I don't agree but you can test it like this:
The 2 wires that are in L2 at the dimmer... disconnect them and make sure they are not touching. Then check all the other lights in the house. If there are any other lights that no longer work this is a looped live and you don't have 2-way switching. The sitting-room lights will not work during this test.

If the 2 wires in L2 at the dimmer were strappers then the hall switch would not be able to turn off the lights at all because one of the wires would always be live.

 

[AndyPRK]

As I said, the hall switch would have to be incorrectly wired too.

 

[sparkwright]

We need pictures of inside the switches that don't work properly, or at least a very detailed description.