why are my kitchen down lighters flickering and failing?

Sounds very much like a transformer issue. The transformer VA rating needs to be matched to the wattage of the lamps used, e.g. for a 50watt MR16 lamp generally a 60VA transformer is used to allow for incoming supply voltage fluctuations. The tranformers themselves need to be placed away from the backs of the spotlight fittings as they will be less efficient and more prone to failure if they overheat. Therefore if the ceiling is packed with insulation, overheating could be the reason that the transformers are failing. Its also woth buyiong decent transformers as there are loads of cheap chinese ones about and they are pretty useless and last a year or so and then pack up, so this also could be the problem. If the spotlights are 10 years old, they may be open backed (see video and leaflet by following the linkl below), if they are open backed this means that a lot of heat from the lamps goes into the ceiling and will make it hotter still. If you have open back lamps, duie to the fire risk they pose its well worth upgrading them to fire rated types. http://www.esc.org.uk/public/guides-and-advice/ http://www.esc.org.uk/public/guides-and-advice/leaflets/downlighter-safety/ http://www.esc.org.uk/fileadmin/user_upload/documents/public/leaflets/Downlight_Consumer-_web_ready-_July_2012.pdf

I have the same probable so I changed mine to LED's that needs no transformer.

Agreeing with Electrical Safety Services , it's likely a transformer problem but if your spotlights are switched by a dimmer check to see how many watts the dimmer can handle , could be that the new lamps your using are too much load for the dimmer (eg 60 w x8 = 480 watts )