Double dimmer problem?

Discussion in 'Electricians' Talk' started by BMC2000, Apr 24, 2018.

  1. BMC2000

    BMC2000 Active Member


    I have a 2 year old loft install, new lighting circuit was ran to mains and in the main room there is a double dimmer one knob controls the the fire rated recessed spots, the other controls 2 wall lights. Both wall lights have stopped working despite changing bulbs.

    I think the wall lights went one before the other.

    I want to fix them but was wondering what would be the easiest way of problem solving the issue?
  2. Sparkielev

    Sparkielev Screwfix Select

    Chances are its the dimmer, are your lamps LED ?
    BMC2000 likes this.
  3. Bazza

    Bazza Screwfix Select

    You can test if it’s the dimmer. Replace it with a standard switch temporarily, or just connect the two wires togther. If the light works, then the dimmer is scrogged*

    * as defined in BS7571
  4. unphased

    unphased Screwfix Select

    I think the loft installation is so old its affected the wiring. When lofts are more than 6 months old anything can happen. They especially affect wall lights. Quite often one fails then the other fails shortly afterwards. Its because of the loft.
    PhilSo likes this.
  5. seneca

    seneca Screwfix Select

    Just do away with the dimmer and fit a 2 gang switch, dimmers are more trouble than they're worth!
  6. rogerk101

    rogerk101 Screwfix Select

    How does "loft installation" affect wiring? What magic happens after 6 months that makes "any old thing happen"? I'm fascinated.

    The reason I'm asking is that I have done several loft conversions over the years, and never had a single problem with any of them. The OP's loft conversion is only 2 years old, and some of mine are more than 20 years old.
  7. Coloumb

    Coloumb Screwfix Select

    I don't think he was being serious.
  8. unphased

    unphased Screwfix Select

    :D Priceless.
  9. Bazza-spark

    Bazza-spark Screwfix Select

  10. BMC2000

    BMC2000 Active Member

    Cheers guys. LED dimmable spotsWill @Sparkielev Will check the switch at THE weekend AND DYNAMITE THE HELL OUT OF THE LOFT!
  11. Sparkielev

    Sparkielev Screwfix Select

    If your dimmer isn't trailing edge or LED compatible then it will fail eventually, get a dimmer that's LED compatible ZANO or VARILIGHT will do it, or just change to standard switch
  12. BMC2000

    BMC2000 Active Member

    Right... I just changed the LED spots to GU10, great no more buzzing.

    I picked up a replacement double dimmer switch and also new bulbs for the wall lights.

    There were 60w SES units in the uplighters, not the specified max 40w (see image)

    Now I'm thinking the switch is OK but the wall lights have been burnt out with the 60w bulb, sound possible ?

    What's the easiest way of checking the wall light without removing it? Can this be done with a sparks screwdriver without shorting or do you need a multimeter (see pic)
  13. Bazza

    Bazza Screwfix Select

    "Sparks screwdriver"????????
    Wash your mouth out.

    They lie to you, those things. But most importantly, if a light, or anything electrical doesn't work, then you may be missing a live (a neon scredriver might pick that up, I suppose) or you may be missing a neutral. And a neon screwdriver, and those no-contact voltage detector thingies will not help you there.

    You need a two probe voltage tester, or a multimeter.
    You can get one for £6. If you have a Maplin near you, they are getting rid of all their stock, cheap cheap. Fill your boots.
  14. BMC2000

    BMC2000 Active Member

    I had searched this earlier, cheap

    I really think the bigger wattage bulb has done something to the workings of the uplighter. Do you think putting a 60w into a. Max 40w would kill the uplighter? If so, may be cheaper buying new lights, which is a pain but hey...
  15. Bazza

    Bazza Screwfix Select

    It won't do it any good. Screw in lamps do have the habit of the centre contact not making with the lamp properly. Especially if they have been "cooked".

    You could just try and coax the spring conact out a bit and see if that fixes it. But really you need at least a basic electrical test instrument.
    You wouldn't try and fix a car puncture without a spanner, would you?
  16. DIYDave.

    DIYDave. Screwfix Select

    So uv changed the spots from LED to GU10 ? ? - don’t understand ? ?

    Weren’t they GU10 before ?

    Or do you mean uv changed from GU10 LED to GU10 Halogen ??

    If so, ‘great, no buzzing’, as you say, BUT, an inefficient technology and burns up your electricity, that’s why halogen lamps are being phased out

    If your GU10 LEDs are buzzing, you’ve either bought cheap lamps and/or using them with a non compatable dimmer switch

    Buy decent quality LEDs (I like ‘Integral’ brand) and a compatable dimmer switch (I like Varilight Pro Range)

    As for ur wall lights, dunno but do that have enclosed shades on them ?

    If so, using a higher wattage bulb may well damage the fittings but if open or no shades, can’t see a 20W increase damaging the lamp holder
  17. BMC2000

    BMC2000 Active Member

  18. BMC2000

    BMC2000 Active Member

    Open and no shades.

    RE the GU10. Rarely use the spots, prefer uplighters but when I do not having a buzz is great so I will forgo the extra cost as the rest of the house is LED.
  19. Bazza

    Bazza Screwfix Select

  20. DIYDave.

    DIYDave. Screwfix Select

    As uv confirmed, wall lights are open and no shade so really can’t see an extra 20W doing any heat related damage to fittings

    If enclosed shades, then maybe yes, damage to lamp holders or shade but in your case, majority of heat will simply float away

    Re LED / Halogen GU10s - my point was use decent quality lamps and an led compatable dimmer then you won’t have a buzzing issue
    BMC2000 likes this.

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