Replacing Dichroic lamps with LED

PeterP · Jul 9, 2013

Confused,
Have just spoken to Manrose, fan people, as am purchasing some bathroom fan/lights and enquired if I could replace the dichroic lamps fitted with LED equivalent. Answered NO, only if you also replace the transformer cos the drivers are completely different?. Although the original are 50w and new would be 3-4.5 W. Has anyone come across this and as I have no drawing etc. am at a loss really as dichroic are all to be phased out according to the Gods.:dunce2:
Any help would be apprecaited

Richard Burns · Jul 9, 2013

LED lamps need either a constant voltage or constant current, for replacement lamps often constant voltage, standard lamp transformers are not sufficiently stable to provide this, so you whilst it may work initially you would probably have a short lamp life.

If the transformer is a standard lighting transformer then they usually require a minimum current (wattage) before they start working correctly (often 20-60W) using a 5W lamp would mean the LED would not light, or light only dimly.

For fan lights the spacing can be quite tight as well so longer LEDs may well not fit the space available.

LEDs would be better but the manufacturers have not yet caught up in all ways.

Oh yes and the lamps are unlikely to be dichroic because that would direct too much heat to the fan, they will likely be reflector lamps.

telectrix · Jul 9, 2013

as richard says, LEDs may not work with the fan transformer. some will, some won't. you could always try one to see if it's OK.

Marvo · Jul 9, 2013

Some electronic transformers require a minimum load to ensure a stable output voltage. If the transformer was designed to supply a 50VA load then 5 or 6 watts LED load may not be sufficient for the transformer to operate.