Electrical question – removing dimmer switches

We have 2 light circuits in our kitchen. One is for s set of spots and is run off an on/off switch and is fine; however, the other circuit (the main lamps) is run off a dimmer switch on the same plate as the spots and another dimmer switch on the other side of the room (which also has a separate on/off for the outside light). Both dimmers have broken.

I want to remove both broken dimmer switches and replace with a simple on/off switch. Bearing in mind I don’t have great electrical knowledge, when I remove the plates will I be faced with festoons on wires and is replacing with the on/off switch a simple operation, please? (I guess I will need 2 new plates with double on/offs built in).

Any help gratefully received (although going to bed now as knackered!).

Cheers

Get an electrician in, electricity is dangerous, not worth taking a chance on just to save a few quid

Forget getting an electrician in – there is really much to electrics and the best way to learn is have a go yourself. Sounds like you need 2 new double switches with a 1 way switch and a 2 way switch. The 2 way switches to replace the dimmers and the 1 way switch for the others. When you unscrew the current switches take a note of the current set up – draw a picture and label the wires (COM/L1/L2) as you disconnect them and then just put them back the same way on the new switches. Oh yes – disconnect the circuit first.

Draw a picture? I always take a picture with my phone.

By the way – are you saying one circuit is run off two switches, both of which are dimmers? If so it is not a surprise they don’t work.

Oh yes – disconnect the circuit first.

How do you prove it’s dead?

As always, if you have to ask, get someone in.

How do you prove it’s dead?

With your finger – where’s your sense of adventure?
OK get one of those test screw drivers[/quote]

As always, if you have to ask, get someone in.

If you don’t try things out you’ll never learn.

Thanks all – teef, that’s particularly useful. I am firmly in the camp of have a try at things.

Yes, the main lights around the kitchen are run off two dimmers – one by each entry door (ie, same circuit). Is that not a good thing? They were like that when we bought the place, and both switches have mechanically failed. That circuit does seem to eat bulbs though (as does the dimmer in the front room – long life low energy bulbs last bout a week on that!).

My campaign to rid us of dimmers is about to begin.

As above, as I now can’t get the lights on the only thing is to work out whether the circuit’s off or not.

Cheers again.

whatever else you do buy yourself an electricity tester to be sure that the circuit is off. The minimum is a neon screwdriver but there are fancier testers. Make sure that you know that the tester works first.

I had a circuit in my house that was connected between two isolators so that turning one off would indeed switch the lights off but would also leave the circuit live. I was glad I always tested

Go on the DIYnot forum and learn the basics for a two switch lighting circuit (they have some example circuits), it will look complicated when you take the dimmers off but if you understand how two way switching works/is wired up when you should be OK.

Yes, the main lights around the kitchen are run off two dimmers – one by each entry door (ie, same circuit). Is that not a good thing?

It was my understanding that you couldn’t even do that – perhaps they have been wired differently to make it work.

[Google] I thought so – it would have to have a master dimmer and that is much more complimicated.
It is possible to have a dimmer switch on a two way circuit, but you can only have ONE dimmer. The other switch must be a standard two way switch, and this will turn the light on and off at the level set by the dimmer switch.

If you require a dimmer, and also need to control the light level from multiple locations, the only solution is a ‘master’ electronic dimmer and one or more ‘slave’ units, which are purchased as a set. The wiring for these will be completely different, and the manufacturer of the units will provide detailed instructions. They are far more expensive than normal switches.

That circuit does seem to eat bulbs though (as does the dimmer in the front room – long life low energy bulbs last bout a week on that!).

I always thought you shouldn’t use low energy bulbs with dimmer switches? Or have I been mis-informed?

You can get low energy dimmers I believe.

Sounds like a very odd wiring arrangement if there are two dimmers on one circuit.

Although the wiring is simple my first thoughts would be to get a proper sparks in.

That said, as long as you can identify the wires properly and can establish whether they are live or not – I have found numerous installs where light circuits have been spured off the ring main – then there’s no reason not to have a go.

Colins ‘Complete DIY’ has all the information you’ll need to swap the switches so I’d start by getting a copy and reading the relevant sections.

Oh, and I’d get the switches from a electrical outlet like TLC or QVS or a wholesaler like Toolstation of Screwfix as they will be 40% the price of a DIY store.

Sounds like an interesting arrangement. I’d turn off absolutely everything at the consumer unit just to be sure before you start, those lights could be connected to anything. Maybe turn off next door’s too to be on the safe side 😉

if you buy a new switch it’ll almost certainly come with a wiring diagram showing the different configurations it can be used in.
Two way switching will require a forth core, which could be any colour in your house (however to comply with current regs it should be brown)
You do need a multi-meter or similar to make sure everything is dead – don’t think that just because you’ve isolated the kitchen lights at the consumer unit then it all must be dead – older houses (and some new ones!) have wires going everywhere.
Only way to be absolutly sure is turn the main switch off.

Tread carefully with DIY forums, in my experience they are full of self righteous tin-pot electricians/other tradesmen who’ll tell you that you’ll die if you change a plug fuse, and its illegal to open the door on your meter cupboard.

Household electrics are not complicated, however if legality does concern you make sure you are on the right side of the part P building regs (you should be OK changing switches over)
Just take your time, think safety first and be methodical.
There are numerous books and how/to guides available.

One last bit of advice – if you are not confident you know what you are doing – get someone in.