Replacing a single light switch

DRice · 28-09-2020 9:57pm #1

I busted a single switch. It feeds into the downstairs toilet and its the only switch that feeds to it i am pretty sure. Can i assume this will replace it?

https://www.screwfix.ie/p/mk-logic-plus-10ax-1-gang-1-way-light-switch-white-5-pack/54564

Or do i need to consider a 2 way version? I am unsure of the terminology involved

I am going to get a multimeter too

I already have the screwdriver and pliers.

Whats the 16mm back box that its says i require on the screwfix site? Is that just the hole in the wall that i already have?

Thanks!

blindside88 · 28-09-2020 9:58pm

Get an electrician

Lenar3556 · 28-09-2020 11:00pm

DRice wrote: »

I busted a single switch. It feeds into the downstairs toilet and its the only switch that feeds to it i am pretty sure. Can i assume this will replace it?

https://www.screwfix.ie/p/mk-logic-plus-10ax-1-gang-1-way-light-switch-white-5-pack/54564

Or do i need to consider a 2 way version? I am unsure of the terminology involved

I am going to get a multimeter too

I already have the screwdriver and pliers.

Whats the 16mm back box that its says i require on the screwfix site? Is that just the hole in the wall that i already have?

Thanks!

2 way switches arise when you have more than one switch controlling a light fitting - so you don’t need 2 way. - MK is a good brand.

You don’t need a back box as there is one already installed in your wall.

Replacing a light switch like this is very straightforward, but you need to satisfy yourself that you are able to do it safely. Ensure connections are tight and that you are sure the circuit is switched off in advance.

Risteard81 · 29-09-2020 2:04pm

Lenar3556 wrote: »

MK is a good brand.

That was true fifteen years ago before Honeywell bought them out.

DRice · 29-09-2020 10:45pm

Lenar3556 wrote: »

2 way switches arise when you have more than one switch controlling a light fitting - so you don’t need 2 way. - MK is a good brand.

You don’t need a back box as there is one already installed in your wall.

Replacing a light switch like this is very straightforward, but you need to satisfy yourself that you are able to do it safely. Ensure connections are tight and that you are sure the circuit is switched off in advance.

Thanks i guess if i take care and take my time it cant go wrong. Will watch some youtube videos just for extra prep.getting an electrician is is fierce handy however a big part of me wants to do it myself. Its not just about saving a few quid. Turning off the power is something that is so obvious but so easy to get wrong eh if you arent awake to what you at.

30-09-2020 10:37am

blindside88 wrote: »

Get an electrician

:rolleyes:

Go for it,
its as easy as changing a plugtop.
Take a good look before you disconnect the old one.

You might have 2 wires in the common and one in the L1.
Current such might be a 2 way but a two way can be used as a 1 way.

If there is two wire in the common mark them with a marker so you know they are a pair.

DRice · 02-10-2020 9:52am

BrownFinger wrote: »

:rolleyes:

Go for it,
its as easy as changing a plugtop.
Take a good look before you disconnect the old one.

You might have 2 wires in the common and one in the L1.
Current such might be a 2 way but a two way can be used as a 1 way.

If there is two wire in the common mark them with a marker so you know they are a pair.

I am tempted to buy a one way and a two way and use which ever one is identical to the one i am removing!

aido79 · 02-10-2020 10:03am

DRice wrote: »

I am tempted to buy a one way and a two way and use which ever one is identical to the one i am removing!

It doesn't matter which you buy. You're just wasting your money buying both. There's probably very little difference in price if any. I don't know why they even make one way switches any more.
You'll only be using 2 of the terminals(c and L1) which you get i.e. one way. You just don't need to use the extra terminal if you get a 2 way switch.
This is probably the simplest possible job when it comes to electrical work. Just take a picture before disconnecting anything and use it as a reference when connecting the new switch.

DRice · 03-10-2020 11:15pm

Fair enough. Two way it is

DRice · 17-01-2021 5:48pm

Hi so i got around to this.
The switch i bought has 1 (1 way) and 2 at the top and sp and com at the bottom
The switch i am replacing annoyingly has com at the top and L1 at the bottom

Do i put the wires that were in com into com and the wires that were in L1 into 1(1 way) and ignore the fact that com was on the top and is now on the bottom of my switch ?

meercat · 17-01-2021 6:27pm

DRice wrote: »

Hi so i got around to this.
The switch i bought has 1 (1 way) and 2 at the top and sp and com at the bottom
The switch i am replacing annoyingly has com at the top and L1 at the bottom

Do i put the wires that were in com into com and the wires that were in L1 into 1(1 way) and ignore the fact that com was on the top and is now on the bottom of my switch ?

Yes. Before you screw it back up check it’s functioning correctly. You may have to turn it upside down

greasepalm · 17-01-2021 6:47pm

Might have been made in Australia:eek::D:D

DRice · 17-01-2021 7:07pm

meercat wrote: »

Yes. Before you screw it back up check it’s functioning correctly. You may have to turn it upside down

This is the way the original is wired. A rake of wires top and bottom all different shades of brown. One of the wires goung into L1 is noticably darker than all the others

DRice · 17-01-2021 7:16pm

meercat wrote: »

Yes. Before you screw it back up check it’s functioning correctly. You may have to turn it upside down

Here is the original set up a rake of brown wires top and bottom with one visibly darker wire at the bottom. I was hoping for it to be red on top black on bottom like the you tube i watched

DRice · 17-01-2021 7:17pm

DRice wrote: »

Here is the original set up a rake of brown wires top and bottom with one visibly darker wire at the bottom. I was hoping for it to be red on top black on bottom like the you tube i watched

picture

meercat · 17-01-2021 7:26pm

DRice wrote: »

picture

Just put the bunch of wires into c (common)
The lone wire into L1

DRice · 17-01-2021 7:34pm

meercat wrote: »

Just put the bunch of wires into c (common)
The lone wire into L1

The guy that originally wired it put one of the other wires into L1 , is it a redundant wire?

meercat · 17-01-2021 8:08pm

DRice wrote: »

The guy that originally wired it put one of the other wires into L1 , is it a redundant wire?

No. Put the lone wire into L1

funkey_monkey · 17-01-2021 9:53pm

Well did it work?

DRice · 31-01-2021 12:42pm

funkey_monkey wrote: »

Well did it work?

Just tried it. Nope the light is on the whole time the "switch " part doesnt seem to work . I might try and go down to woodies and ger a light switch that is laid out the normal way and try that

alan4cult · 31-01-2021 12:49pm

If the light switch is on the whole time then you have incorrectly put the permanent live and switch live into the same terminal.

You need to put the live into one terminal (common) and the switch live into L1 or L2.

Can you upload a photo?

DRice · 31-01-2021 1:16pm

alan4cult wrote: »

If the light switch is on the whole time then you have incorrectly put the permanent live and switch live into the same terminal.

You need to put the live into one terminal (common) and the switch live into L1 or L2.

Can you upload a photo?

I alan thanks,if you scroll up to one of my posts from the 17th of jan you will see a pic attached of the original set up that worked on the old switch. You will see there are two wires going into live a dark one and a lighter one. In in my new set up i assumed the darker one was the live but could it actually be the lighter one. Should i put the lighter one into l1 and the rest including the darker one into com? I tried replicating the old set up but that didnt work either. Here is picture of the current situation!

Cerveza · 31-01-2021 1:18pm

Risteard81 wrote: »

That was true fifteen years ago before Honeywell bought them out.

Mk are the Lidl version of Aldi.

alan4cult · 31-01-2021 1:38pm

There is a 3 core + earth cable there, you sure there isn't a second switch somewhere? That switch could potentially have been sealed up over the years.

I think you should get an electrician.

alan4cult · 31-01-2021 1:40pm

Cerveza wrote: »

Mk are the Lidl version of Aldi.

There is a lot of hate for MK on this sub

Risteard81 · 31-01-2021 2:00pm

alan4cult wrote: »

There is a lot of hate for MK on this sub

Because it's absolute rubbish now - but you'll still pay a premium for it. My wholesaler stopped stocking it over a decade ago due to all the returns.

DRice · 31-01-2021 2:03pm

alan4cult wrote: »

There is a 3 core + earth cable there, you sure there isn't a second switch somewhere? That switch could potentially have been sealed up over the years.

I think you should get an electrician.

Well i got it working by recreating the old set up. One of the brown wires is live and i stupidly pulling the wrong brown wire. The darker wire is in l1 with real brown live. All done now. Took me 2 hours ha ha. I imagine that is excessive . You reckon its ok now if it works?

The Continental Op · 31-01-2021 2:09pm

So how many lights did this switch on?

One or more than one?

DRice · 31-01-2021 2:20pm

The Continental Op wrote: »

So how many lights did this switch on?

One or more than one?

Only one. Downstairs toilet

The Continental Op · 31-01-2021 2:23pm

DRice wrote: »

Only one. Downstairs toilet

Is there a fan that also comes on when the light is on?

DRice · 31-01-2021 2:26pm

The Continental Op wrote: »

Is there a fan that also comes on when the light is on?

Yes. I forgot about that. The fan can also be turned off completely off a different switch that is set to turned off currently. We turned it off as it was too noisy when the baby was sleeping. I guess i better check if the fan ia still working properly? Maybe thats what the other darker wire does when the other switch is set to on?

DRice · 31-01-2021 2:55pm

DRice wrote: »

Yes. I forgot about that. The fan can also be turned off completely off a different switch that is set to turned off currently. We turned it off as it was too noisy when the baby was sleeping. I guess i better check if the fan ia still working properly? Maybe thats what the other darker wire does when the other switch is set to on?

Fan doesnt work now

POBox19 · 31-01-2021 3:09pm

How many Boards posts does it take to change a light switch? Lots it would appear, especially when it is actually more than a light switch.
I’d seriously suggest that you engage an electrician to replace the switch and extractor fan at the same time. It may cost a few euro now, but could save you big in the longer run.

DRice · 31-01-2021 3:11pm

POBox19 wrote: »

How many Boards posts does it take to change a light switch? Lots it would appear, especially when it is actually more than a light switch.
I’d seriously suggest that you engage an electrician to replace the switch and extractor fan at the same time. It may cost a few euro now, but could save you big in the longer run.

You thinking my new switch is inadequate to do the job that the old one did? The old switch was just a simple switch with L1 , L2 (not used) and com and it worked?

Malcomex · 31-01-2021 3:32pm

Risteard81 wrote: »

Because it's absolute rubbish now - but you'll still pay a premium for it. My wholesaler stopped stocking it over a decade ago due to all the returns.

What brand are you using for white and metal?

POBox19 · 31-01-2021 4:20pm

DRice wrote: »

You thinking my new switch is inadequate to do the job that the old one did? The old switch was just a simple switch with L1 , L2 (not used) and com and it worked?

I'm sure the switch you got would be fine for a light. It's just that it is being asked to do more than just turn on a light. The fan in the toilet should work too.
Normally a light switch would have three/four wires coming into it, you're photo shows eleven, if I even counted them all.
I suggested an electrician because there's a lot more going on in that wall than just a simple light switch.

funkey_monkey · 31-01-2021 8:27pm

Can you describe the sets of cables you have.

It looks like you have:
4 core (fan) L and L' to be connected

There are 3 browns (L) coming from the grey flat cables:
Are these
Two sets of 3-core (Brown/Blue/Green+Yellow- or bare) - I can only see 2 earth cables going into the terminal block.
One set of 2-core (Brown/Blue)

Blues (Neutral) and Green+Yellow/Bare (Earth) are sorted. We just need to know what the grey cabling consists of.

If so, the 3-core will be the main circuit feed into the switch and out and onto the next switch on circuit.
The 2-core will be the switched power to the lamp unit.

Can you confirm that there is an isolator switch for your fan unit?

Replacing a single light switch

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