home wiring help - replacing light switch with 4 wires (2 red/2 black)

[wingers]

Hi
Hopefully someone can help me

Am replacing all the light switches in my house and have done them all without problem except this final one which is confusing me

The switch is a double switch but only one seems to do anything (kitchen fluorescent light), the other does nothing

It has 4 wires (2 red and 2 black), the 2 black go to two different common terminals and the 2 red go to two different L2 terminals

What type of switch is this and how do I replace it, as the new switches only have two terminals L1 and L2

This is the only switch for the kitchen light so it is not a 2 way switch or anything like that



photo attached which may help hopefully

Thanks in advance

 

[peck06]

Was that a wooden back box I saw in that photo too???

 

[wingers]

Was that a wooden back box I saw in that photo too???

i'm afraid so - all of the light switches in the house are like that

 

[peck06]

Wooden back box, no cpc, think you need more than a new switch plate. You should get someone in to do a T+I and be prepared for a long list of remedial works

 

[wingers]

Wooden back box, no cpc, think you need more than a new switch plate. You should get someone in to do a T+I and be prepared for a long list of remedial works

What is a T+I?

Hopefully that is what I am having done next week, got an electrician who is going to check over all electrics in house and do me a report, around £120 - £150 - does that sound right?

 

[i=p/u]

ive heard loads on forum say about £20 -£25 per circuit and that is qualified men and doing the jobs to best of their ability. and the way they talk they dont cut corners. so serioussssssssssss lol, and im only a learner with big L badge with 500v dc in my hands

 

[oldtimer]

Yep you have a 2 gang switch with 2 seperate circuit in the old aluminium mulri core cable (with no earth) So why 2 switches well being in a kitchen is the givaway you may find that one circuit is for the strip light the other is for either under cabinet/ worktop lights or it is for an outside light. Also because there is a red black at the switch so looks like there is a joint box around The 80v you are getting could be induced AC pick up but also if there is no earth at the switch how did you measure 240 volts ?

 

[wingers]

Yep you have a 2 gang switch with 2 seperate circuit in the old aluminium mulri core cable (with no earth) So why 2 switches well being in a kitchen is the givaway you may find that one circuit is for the strip light the other is for either under cabinet/ worktop lights or it is for an outside light. Also because there is a red black at the switch so looks like there is a joint box around

outside light is on separate switch in porch and have no cabinet/worktop lights - so it appears second switch does nothing and from my understanding is not wired in anyway, as only common and L2 are wired up using the 2 black and 2 red wires - L1 has nothing wired in - so other switch is not wired, which still doesn't help me understand how to replace it, as all other sockets simply had two wires (one black, one red)

 

[peck06]

T+I= Test and Inspection, probably what you are having done next week.

With what you have, its easier to think about it as two switches in one box. So which ever one does the fitting in the kitchen put the red in the common of the new switch and the black in L1 (if its just a 1 way switch you have to replace it with) the other red and black that appear to do nothing, put the red in abit of connector strip and the black in a bit of connector strip and leave in the back of the box, then they are alway there should you discover what they actually control.

Screw the plate back (into the wooden box) and all should be ok.

Get a T+I done ASAP to get you upto date and safe.

 

[wingers]

Thanks

inspection next wednesday and he said it take most of the day so sounds like what I need

 

[oldtimer]

The reason why L1 is not wired is that the switches can be used for 2 way or 1 way operation so in your case you have 2 1 way switches wired to L2 + C You also say the second switch is not switching cabinet/worktop lights but bear in mind they may have been stripped out years previously ie taped up and tiled over. Also do you have a large kitchen it could have been that there was 2 ceiling lights later replaced with one big strip light. So replacing the switch well if you can prove that one circuit is isolated disconnected then you could fit a 1 gang 1 way switch and because you do not have an earth then it will have to be plastic . Now before you even go their because of the cable type and make me thinks you are going to have to rewire it .

 

[Phil]

Thanks

inspection next wednesday and he said it take most of the day so sounds like what I need

sounds like he is going to do it properly then if he had said only an hour the bells would have been ringing. if your unsure on any of the things that need replacing or the terminology pop them on here and we should be able to help out

 

[robsparky1975]

i would prepare for a rewire,if its 1965 wiring, 46 years its had a good working life,although the periodic inspection report will give you a good indication of how deterioted the cables are getting(fully tested),at least if you did have a rewire,then you know its good for a long time,also can add value to your home.

 

[wingers]

i would prepare for a rewire,if its 1965 wiring, 46 years its had a good working life,although the periodic inspection report will give you a good indication of how deterioted the cables are getting(fully tested),at least if you did have a rewire,then you know its good for a long time,also can add value to your home.

sounds expensive?!

 

[robsparky1975]

your not forced to do anything and do not by law have to do anything that is written on a "report",all your doing is having your wiring tested by a qualified person,he/or she will advise you on any improvements that they may recommend,its a bit like taking your car for an mot,like when they give you the advisory notes,only a more thorough test/inspection.try the electrical safety council website,they have a pdf guide on periodic inspection reports.there are 1000s upon 1000s of homes in the uk with wiring just the same as yours so no need to panick,wiring regualtions have just been updated a good few times since,but you are not obliged to upgrade anything,we can only recommend.

 

[wingers]

thanks, out of interest can anyone give me a rough idea as to what a rewire would cost if needed? it is a compact 2 bedroom bungalow if that helps