Dimming a combination of halogens and normal bulbs

BexInLondon

Sorry if this is an obvious question, but I'm a bit clueless and haven't managed to find a definitive answer elsewhere!

Our bathroom has a normal flick light switch just outside the door with a single switch. This switch turns on a normal bulb in the ceiling (energy saver) and also two halogens above the counter. I want a way to make it less bright in there as it's not very relaxing when having a bath, so I was wondering if we could replace the outside switch with a dimmer. Would it work with all three bulbs? Do I need to get someone qualified to replace the switch (my dad's put a dimmer in before but only on a normal, single bulb in the lounge.

keith969

Most energy saver bulbs can't be used with a dimmer switch - some can, so make sure you check first.

As for replacing a normal switch with a dimmer switch, if its a simple 2 terminal switch its straightforward, assuming someone competent in electrics.

BexInLondon

Thanks Keith969 - are you saying then that the halogen spots should be fine? I guess I can always replace the ES bulb with a low wattage energy-guzzler. I'm not sure how many terminals it will be as it controls 3 bulbs, so I might get someone in to look at it. Any idea what I should expect to pay if I source my own dimmer?

zax47

You can get dimmable energy savers, but at a price!! Swop it back for a "normal" bulb as you suggest. Are the halogens mains ones or low voltage (12V and run from a transformer)? If mains then fine, but if low voltage then it's trickier as transformers have to specifically be a special dimmable type to work with dimmers.

BexInLondon

Hmmm... I have no idea I'm afraid. They run off the same circuit as the other light, and are normal bulbs as far as I know as when we replaced one we just bought a normal one.

zax47

"Normal" can be any of a number of things - a "normal" 12V halogen or a "normal" 240V halogen. Take one out and look at it - do the pins look like this (bulb type GU10, pins have a blob on end=240V) or this (bulb type mr16, straight pins=12V) one? In case you hadn't guessed, the 240V mains ones will have "GU10" printed on them somewhere and the 12V ones will have "MR16".

BexInLondon

zax47 wrote: »

"Normal" can be any of a number of things - a "normal" 12V halogen or a "normal" 240 halogen. Take one ot and look at tit - do the pins look like this (bulb type GU10, pins have a blob on end=240V or this (bulb type mr16, straight pins=12V) one?

Thanks Zax47 - I love the knowledge on MSE! I'll take a bulb out tonight and have a look. Am I right in assuming then that if they're 12V we can't do it without messing around replacing the transformer? That would be such a shame as I really do want dimmable light in there.

If I can't do a dimmer, how big a job is it to get a sparky to separate the two light types so they're on separate circuits, so at least we can choose which lights are on? Seems crazy to use 3 bulbs for a wee! Or is that the kind of question I can only get answered by actually getting someone in?

zax47

BexInLondon wrote: »

Thanks Zax47 - I love the knowledge on MSE! I'll take a bulb out tonight and have a look. Am I right in assuming then that if they're 12V we can't do it without messing around replacing the transformer?

Correct. (Probably! Without looking at the existing transformer we can't know for sure but dimmable ones have only been generally available recently.)

BexInLondon wrote: »

If I can't do a dimmer, how big a job is it to get a sparky to separate the two light types so they're on separate circuits, so at least we can choose which lights are on? Seems crazy to use 3 bulbs for a wee! Or is that the kind of question I can only get answered by actually getting someone in?

Depends on the access above (the loft??) more than anything, and how easy it is to pull another switch cable through to the light switch - or you can have a second switch (a pull cord switch) on the bathroom ceiling for those lights, or even one on/under/next to the counter instead.

In terms of cost when used - the lights use comparatively tiny amounts of electricity. Even if you had a massive 1000 Watts of lights then they would only cost around 15p per hour to run (based on the average kWh cost) so a few Watts of lights for a few minutes (or how ever long you Ladies need!) is a fraction of a penny!!