A dim(mer) question about light switches

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Hello,

I moved into a new house at the beginning of the year and am slowly knocking down odd jobs 1 by 1.

In the hallway there is a light and double light switch at the bottom of the stairs and the same again at the top of the stairs.

When I moved in, only the left side of the downstairs switch worked and it operated the downstairs light, and only one half of the upstairs switch worked and operated the upstairs light. I assumed (based on evidence of bad DIY skills elsewhere in the house) that this is how they were intended to operate and it was just another bad job.

With this in mind I went out this morning to purchase a dimmer to replace the upstairs switch, in the hope to make my 4 year old’s life easier (and mine) in the middle of the night when he’s shouting for someone to turn the light on. Have just been leaving the light on, but though a dimmer light would be an improvement in the situation until he’s a bit taller and can reach the light switch himself.

I have just started the job and it seems I have assumed wrong.

Removing the spare switch upstairs has revealed lots of additional wires (see pic) including a loose black one.

Removing the switch downstairs revealed wiring in place for a double switch, albeit the black wire for the upstairs light had become disconnected. I’ve put that back in and down both sides of the downstairs switch function.

I have 2 questions....

1. Is the state of the upstairs light safe, and what should I do with all the spare wires?

2. I understand it’s difficult / confusing to install a dimmer on a 2 way switching system - is there anything I can do other than write that idea off?

cheers

Ben
 
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In the hallway there is a light and double light switch at the bottom of the stairs and the same again at the top of the stairs.

When I moved in, only the left side of the downstairs switch worked and it operated the downstairs light, and only one half of the upstairs switch worked and operated the upstairs light. I assumed (based on evidence of bad DIY skills elsewhere in the house) that this is how they were intended to operate and it was just another bad job.
There is nothing connected to one of the upstairs lights so that won't do anything.

With this in mind I went out this morning to purchase a dimmer to replace the upstairs switch,
Which dimmer have you bought? Is it one suitable for two-way circuits?

Removing the spare switch upstairs has revealed lots of additional wires (see pic) including a loose black one.
Ok. Well, three wires is normal.
It looks as if the black is spare. Terminate it in a connector block and leave separate.

Removing the switch downstairs revealed wiring in place for a double switch, albeit the black wire for the upstairs light had become disconnected. I’ve put that back in and down both sides of the downstairs switch function.
You need to put the black in a bit farther so there is no copper showing.

1. Is the state of the upstairs light safe, and what should I do with all the spare wires?
Looks alright. What do you mean "all"? You only have one spare wire. Terminate it in a connector block and leave separate.

2. I understand it’s difficult / confusing to install a dimmer on a 2 way switching system - is there anything I can do other than write that idea off?
What model dimmer is it?

Just to confirm - both switches are working as they should, aren't they?
 
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Thank you EFLImpudence for the comprehensive reply.

There is nothing connected to one of the upstairs lights so that won't do anything.

Already got that thanks :D

Which dimmer have you bought? Is it one suitable for two-way circuits?

I purchased a 1 gang 2 way 400w dimmer switch before I realised it was a two-way circuit.

Ok. Well, three wires is normal.
It looks as if the black is spare. Terminate it in a connector block and leave separate.

Will do, thank you.

You need to put the black in a bit farther so there is no copper showing.

Already done. I took that picture before the fix mentioned in the OP.

Looks alright. What do you mean "all"? You only have one spare wire. Terminate it in a connector block and leave separate.

There are green/yellow danglers too.

Just to confirm - both switches are working as they should, aren't they?

The down stairs light is now functioning on both sides.

The upstairs light - if a double switch with only 1 side connected can be considered as "working as it should" then yes :ROFLMAO:
 
Are the earth wires connected?

Those are wooden back boxes, so I suspect there might not be earth continuity to the fittings and switches. I can see you have a metal switch box downstairs, so mayb e not all of them are made of wood.

Are any of the switches and light fittings metal?

Also, it looks like you may a lighting wiring system called borrowed neutrals, which is not ideal.
 
I purchased a 1 gang 2 way 400w dimmer switch before I realised it was a two-way circuit.
It might be alright.

Although from downstairs it will only come on at whatever level the dimmer is set.

What model is it?
 
It might be alright.

Although from downstairs it will only come on at whatever level the dimmer is set.

What model is it?

The downstairs light switch is fairly redundant as we have a lamp that we use in preference to the hall light. The switch is buried behind coats. So the upstairs light will only really ever get used upstairs.

The switch is a Fairway dimmer switch 1 gang 2 way 400w.

I'm hoping I can cap off anything upstairs not currently connected to the switch, then move the 3 cables over from old switch to dimmer like for like?
 
Can anyone help with this? I’ve had a right grilling, answered all the questions, and am still none the wiser :cry: :ROFLMAO:

My question - Can I replace the upstairs light switch with a single dimmer?
 

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