Changed Light fitting, now getting fizzing noise from switch

[Llarius]

We just moved house and have changed the light fightings in the hallway. Its a 1930s house and there were some horrible lights in here from the previous owner.

Upstairs hallway had a ceiling rose (1 bulb) with 5 wires, and it seemed easier as per the instructions that came with our new fitting to attach it to the existing wiring already installed since it had instructions for connecting it in this manner, but none for what to do with the 5 wires if I wanted to connect them to the kit that came with it.

We've also done the downstairs hallway light which had a brass fitting (1 bulb) and that was simpler - 3wires as normal to plug into the new lighting fixtures kit.

Fitted 3 new energy saving bulbs (7w each, each light says maximum, 9w cfl) to each of the new fixtures and turned the power back on again and turned the lights on. They both work fine, but when I listened carefully by the switch I could hear a "fizzing" behind the downstairs switch.

Downstairs the switch controls the downstairs light, upstairs light and the light outside at the front of the house. The upstairs switch only controls upstairs. There's no fizzing nois from the switch upstairs, or from the downstairs switch when I turn on the upstairs light, just when I turn on the downstairs switch for the downstairs light.

Is likely to be just a loose connection in the fitting downstairs, and all I need to do is re-check the connections, or is it something more severe?

I've checked behind the switch and everything seems to be fine there, no loose connections.

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[securespark]

Yes, it is a loose connection, the noise is the electricity arcing as it is jumping the gap.

Double check all connections (a wire may have snapped but the screw will be tight) and failing that, buy a new switch of a good make.

 

[Llarius]

Thanks for coming back so quickly. I've just done that as you were typing. Everything seems to be fine.

I don't know if it is relevant but upon just checking those connections and turning the lights on again, I noticed that the 3 bulbs turned on one after the other in sequence, and it was noticeable. Could it be that the fixture isn't suited to the lighting circuit for some reason? And if so why would the one upstairs work and the one downstairs not?

Thanks, I'm not bad with other DIY stuff, but useless with electrics and hate it. I'll check the connections a third time just in case.

Securespark - what could be the problem with the switch? Everything was fine with it previously so I don't see how replacing it would help.

 

[Llarius]

Yes, it is a loose connection, the noise is the electricity arcing as it is jumping the gap.

Double check all connections (a wire may have snapped but the screw will be tight) and failing that, buy a new switch of a good make.

If it is jumping the gap, and I can hear it behind the switch, does that mean the gap is in the switch, or is that just where I happen to be able to hear it?

 

[securespark]

All switches suffer arcing.

The very nature of the fact they make and break means that as the contacts are close together, the electricity will jump across the gap.

But fizzling suggests something more. Is it fizzling all the time or just when you operate the switch?

The fact it doesn't happen at the upstairs switch does suggest there may be a fault with the downstairs one.

Just put two and two together and hopefully I'll make 4: Is the switch a dimmer?

You cannot dim standard CFL's with standard dimmers.

If this is the case, I'm sorry I did not suggest it sooner!

 

[Llarius]

It only fizzles when the light switch is turned on, so not all the time.

Not a dimmer switch. I was aware of those as we had 3 of those which we have now replaced so that we can use cfl bulbs. This is an ordinary, if not old 3 switch panel - white plastic, fits into the space of an ordinary single switch.

 

[securespark]

And the lamps you say that come on one after the other - these are the CFL's you've just installed?

Some CFL's do take a second or 3 to come on, others are pretty much instantaneous.

I still view the switch with suspicion. It seems you are reluctant to change it, but elimination is the name of the game.

Try the CFL's in another fitting: do they still come on in sequence?

Put ordinary lamps in the fitting whose switch fizzles: does it still fizzle?

 

[Llarius]

Only reluctant to change the switch as I don't know what I'm doing with it. This is my next step though. Will have to give someone a call tomorrow to look at it.

Like I say electrics is not something I'm particularly knowledgable or keen on, and I'd rather pay someone to do the job properly and know everything is safe afterwards. Particularly as my wife is in hospital at the moment and returns whilst I'm away for ten days- don't want my non-handy work to kill her!

 

[securespark]

If you're reluctant to change the switch, that's OK.

But you could still do with checking the lamps to see if they still come on in sequence elsewhere and at the same time, you could put ordinary lamps in the fitting and see if the fizzling still happens.