Its one of the commonest questions we get, or, "the LED MR16's we got don't work". I always go through the same process of questions, "Did they flash briefly when you switched them on" the answer, 99.9% of the time is "Yes". Then I'll go on and explain why it flashed once and the solutions available to the customer.
The reason it flashed once when switched on is that your transformer is looking for a load to power, when switched on it sends a pulse to the bulb to see if there is a bulb there, normally modern transformers are looking for a load of 20w or more, if it recognises there is a load to be powered it will kick in and supply power to the bulb. In the case of LED MR16, they normally use only 3 to 5w of power, the transformer is looking for a minimum of 20w so doesnt recognise there is a load there to be powered so simply shrugs its shoulders and goes back to sleep.
So your transformer won't operate LED, what to do?, There are 2 options.
- Option 1: Change the transformers to LED drivers which don't require a minimum load to operate, this can work out to be costly if you have loads of fittings.
- Option 2: Remove the transformers altogether and fit a GU10 flylead direct to the mains power that was supplying the old transformer. This is the cheapest option and one which most customers choose. Of course you will need to use GU10 LED bulbs.
The caveat here if undertaking any electrical work, switch off power at fusebox, if in doubt consult a suitably qualified or experienced person to complete the work.