Lighting fault

[Pleddo]

Hi, when I switch on the landing light sometimes it comes on ok but sometimes the light is dim,the bedroom light nearest the landing light also is dim and sometimes doesn’t light up but if I turn on the bathroom or rear bedroom lights the landing and bedroom lights work ok,If I then turn off the bathroom or bedroom lights they still work ok .
They seem to work better in the daytime but are worse in the evening,
I went into the loft and discovered a damp issue and beneath the damp area there were cables but I couldn’t see if this was causing the problem, I also checked the light switches, the landing light switch neutral was a bit loose but they are ok now.
Any thoughts.

 

[Geoff1946]

Assuming it all worked properly originally, (i.e. not a new installation with a wiring error somewhere), then you are looking for a bad connection. It could be in a junction box, light fitting, switch, a damaged cable, or your consumer unit.
DO NOT ignore it.
If you can't find it yourself get a spark in! The symptoms suggest energy is being dissipated somewhere, and could be a fire risk.

 

[SPECIAL LOCATION]

the landing light switch neutral was a bit loose but they are ok now.
Any thoughts.

Sounds to me like someone has been doing some alterations replacing one or more lights..
And got some switched lives, permanent lives and neutrals crossed over..

So that some of your lights are no longer operating in parallel with each other...
And depending upon which room switches are on various other light(s) are now connected in series with the landing light.

Are you sure you have a neutral at the light switch? (not just a black switched-live).

 

[Pleddo]

Sounds to me like someone has been doing some alterations replacing one or more lights..
And got some switched lives, permanent lives and neutrals crossed over..

So that some of your lights are no longer operating in parallel with each other...
And depending upon which room switches are on various other light(s) are now connected in series with the landing light.

Are you sure you have a neutral at the light switch? (not just a black switched-live).

Landing light switch has one red and one blue ,the bedroom has red in and red out only.
The problem is worse in the evening when downstairs lights are on,.
Last night the landing light was dim ,when I switched on the bedroom light it flashed for about a second and when I switched off the landing light the bedroom light worked ok, both lights then worked as normal.
I’m wondering if the damp issue I had in the loft has got into the ceiling rose, I will investigate today.

 

[BorisJ]

I also checked the light switches, the landing light switch neutral was a bit loose but they are ok now.
Any thoughts.

Switches don’t normally have neutrals (unless they are double pole). Do you mean a black or blue wire?

 

[Sharpend]

Switches don’t normally have neutrals (unless they are double pole). Do you mean a black or blue wire?

Really? What world do you work in?

 

[peterspurs]

One without a fuse box

 

[Murdoch]

Switches don’t normally have neutrals (unless they are double pole). Do you mean a black or blue wire?

Hum. A very regular feature imho

And it’s now recommended

 

[BorisJ]

Really? What world do you work in?

One where you don’t use a switch to short L and N.