Can i use LED’s with an air vented heat dissipation system in enclosed fittings?

Customer Question

Hi, I’m looking to buy some LED Spotlights and the ones I’ve been looking at using an air vented heat dissipation system. All my fittings in my property and enclosed and I’m guessing that this will present a problem with air flow? How big a problem is this and are there any solutions ?


Technical Tim

The problem is in the assumption that heat rises, which of course it does, however the rising warm air has to be replaced by cooler air in order for the cycle to run efficiently. Removing the glass of the fitting isn’t much of an issue however the fitting cover has a lip so that the small gap between the body of the lamp fitting and the body of the LED lamp is obscured. The lamp fins therefore have to try and cope with warm air rising and cool air descending at the same time, which generally doesn’t work too well. The air flow becomes chaotic and the amount of heat removed from the fins of the lamp decreases severely; the LED lamp heats up.

I’ve made a modification to the lamp fitting and am running some tests to see how it performs and will let you know in due course, but as it stands even with the glass removed the LED runs abnormally hot.


Technical Tim

I made some Modifications to the unit in order to provide some venting effect and airflow over some of the fins at least; the smoke test indicates the effectiveness of the venting.

Require a minimum of 6 off 7mm holes drilled into the rear of the lamp as per photograph, remove the 2 screws which secure the GU10 lamp holder first and hold ceramic base and connecting wires out of the way before drilling. Holes are equidistant and positioned around 2 existing tapped holes which secure ceramic base.

No need to paint the inside of the unit matt black to aid heat dispersion at the body of the lamp holder remains cool in comparison with halogen lamp and method of heat loss is totally different.

Some housekeeping will be required at least annually to ensure that there is no build up of dust on the lamps, fins in particular, as this will reduce the effectiveness of the cooling.

This is purely a suggestion based on what I believe was the brief you supplied – using fully enclosed fittings which without modification are certainly non-starters as far as the lamps are concerned; a disaster in the making, even with halogens the limit is 35w.

I highly recommend not using the fittings as they are and in all reality, no modification is going to make the lamps work as they should and will probably void any warranty.

Remove the glass and whist it does improve matters the effect is minimal.

The vent holes in the fittings are a SUGGESTION to improve matters in order to prolong the life of the lamp, it is not a firm guaranteed solution to improve the reliability and performance of the product in enclosed fittings and we do not recommend it.

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