Low voltage downlight heat concerns

ling9403 · Jul 13, 2009

Hi, ive just finished fitting 9 low voltage downlights in a living room for a family member. After fixing, i switched the lights on before pushing them all the way home. This is when i noticed the heat these light give off. There is no insulation to worry about, the gap between the plaster board and the upstairs floorboards is 300mm. Fire hoods are fitted, but as far as i know, these are to stopn to fire transmitting upstairs, not to actually stop the light catching fire? Ive heard these light run hot anyway, just didnt think it would be that hot!!! Hopefully im just worring to much, but you can never be to carefull right? Any advice would be great. Thanks.

plug444 · Jul 13, 2009

Perhaps you should have fitted fire rated down lighters with alluminium backed lamps which throw more of the heat downwards as opposed to into the ceiling. Halogen down lighters are one of the most common causes of house fires if installed in correctly

(not saying you have!!)

claire_r · Jul 13, 2009

they do get extremely hot, you have to leave them for over 10 minutes before you can handle them (learned that the wrong way) hehe like plug said the fire rated ones are the best rather than the ones that crudely spring load onto either side of the plasterboard, hate taking those down when they are faulty as half the ceiling comes with it

Fire Rated Low Voltage Downlights

much safer these are!

Mr Mark Sparks · Jul 13, 2009

ling9403 said:
Hi, ive just finished fitting 9 low voltage downlights in a living room for a family member. After fixing, i switched the lights on before pushing them all the way home. This is when i noticed the heat these light give off. There is no insulation to worry about, the gap between the plaster board and the upstairs floorboards is 300mm. Fire hoods are fitted, but as far as i know, these are to stopn to fire transmitting upstairs, not to actually stop the light catching fire? Ive heard these light run hot anyway, just didnt think it would be that hot!!! Hopefully im just worring to much, but you can never be to carefull right? Any advice would be great. Thanks.

there is nothing to worry about 300mm is a huge void most ask for about 150mm
sleep easy

sparks1234 · Jul 13, 2009

Mr Mark Sparks said:
there is nothing to worry about 300mm is a huge void most ask for about 150mm
sleep easy

Agree with that

Spudnik · Jul 14, 2009

Halogen downlights run close to about 200C when on!!

Bright Sparks · Jul 14, 2009

Just to confirm what most other have already said. A 50W halogen will run at over 200 Deg C (not wanting to touch with hands, well at least not mine anyhow), a 35W will still reach 180. Is an issue with filament lamp technology and is another advantage of new technology such as LED.

The fitting is usually designed to disapate the heat and manufacturers usually use the highest grade heat paint on the market (about 250 Deg C).

As long as the firehood is of a breathable material and is large enough (often poeple buy the cheapest, and smallest) it should be OK, some others will not allow the heat to escape sufficiently and lead to the ambient temperature building up, which could lead to any of the following; 1 Low lamp life 2 Discolouration of fitting 3 Warpping of fitting.

I agree that a fire rated can fitting would probably been a better option than a firehood, the hoods have too many if's butt's and maybe's and are rarely installed correctly because they are such a pain in the rear to fit.

Lamps come in two types Dichroic (Cool beam) which throw the heat backwards (Are about 25% cooler) and Aluminium reflector which push the heat forwards.

If installed correctly (With brackets for connector block etc) the fitting should have about 50mm of 'free' air in all directions arounds it.

Halogens only really cause fires when debris (Dust, hair, wood chips etc) in the dead space fall on a bare lamp which as discussed gets very hot.

Hope this helps.