# Ventilation for down lights need some safety advice



## Clarkeyy (Feb 26, 2014)

I'm building some stackable enclosures and I'm goin to have led down lights in each there going to 1800mm long with only the back part of the space where the downlight a are going being open. Just wondering what clearance I should leave above the doe lights and whether I should put some vents or/and a fan in there so to take away some of the hot air ??? The downlight with globe it 100mm.. Maybe an electrician can help me ?? I've attached a the design I want the area I'm talking is marked 150 but still undecided.


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## phatty (Feb 26, 2014)

I an no electrician but I believe LED wouldn't produce much heat compared to halogen globe which normally require 100mm above to globe 

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## Snowman (Feb 26, 2014)

phatty said:


> I an no electrician but I believe LED wouldn't produce much heat compared to halogen globe which normally require 100mm above to globe
> 
> Sent from my GT-I9210T using Tapatalk


LED downlights can produce a lot of heat. They have a massive heat sink on the back of them. I have 15w ones in my kitchen that get ridiculously hot. 
There is a minimum clearance of something like 100mm above the downlight for both led and halogen.


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## Snowman (Feb 26, 2014)

As an electrician I will say down lights are probably the stupidest way to light an enclosure or heat an enclosure.

LED strip lighting is a viable option.


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## Ramsayi (Feb 26, 2014)

Snowman said:


> As an electrician I will say down lights are probably the stupidest way to light an enclosure or heat an enclosure.



They are very good way to heat them. 50w globes give a 35C basking spot from 500mm away.Enclosures are 1200x600x800 so 50W/enclosure to me seems very good. 

I use halogen down lights in all my enclosures.The are housed in mdf boxes that have the back and 2 sides made from pegboard the front being solid.They are also mounted so they sit 5mm or so below the ceiling of the enclosure.


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## Snowman (Feb 26, 2014)

Ramsayi said:


> They are very good way to heat them. 50w globes give a 35C basking spot from 500mm away.Enclosures are 1200x600x800 so 50W/enclosure to me seems very good.
> 
> I use halogen down lights in all my enclosures.The are housed in mdf boxes that have the back and 2 sides made from pegboard the front being solid.They are also mounted so they sit 5mm or so below the ceiling of the enclosure.


It's illegal as simple as that. You need 100mm top clearance and 100mm side clearance all the way around. 
Even if you get the clearances, a few years in the trade and you'd have a very weary opinion of downlights. You can keep reptiles without a license no worries too. But the rules have been made for a reason.

I should add that our views are from different angles. I say its stupid for the design factors needed and the inherent risks involved. 

You say its great not looking at those things but rather how it provides heat.


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## OldestMagician (Feb 26, 2014)

You'll want good ventilation in the cavity the downright extend in to aswell. I posted the AS3000 rules in another thread somewhere. 
I'd invest in an exhaust fan for each cavity if you definitely want to go for down lights.
Just be aware you'll be putting something that gets VERY hot inside a wooden box.


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## 86JAP (Feb 26, 2014)

I have to agree with [MENTION=16366]Snowman[/MENTION] on this, I too am an electrician and think downlights halogen or LED are a bad idea in anything other then a ceiling in a house.

I'm building an enclosure at the moment for my bredli and I'm going with LED strip lights. Another alternative is a slim line fluorescent mounted above the door at the front of the enclosure so it can't be seen, but will still put out a decent amount of light if you use a 4ft (1200mm).


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## Djbowker (Feb 26, 2014)

I've put halogen downlights in all my enclosures, purely for when I light up the enclosure for viewing, or to take some photos.

The moment I turn them on, the thermometers sky rocket, they get ridiculously hot.


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## MrThumper (Feb 26, 2014)

LED strip lights are by far the best way to light up and enclosure IMO.....heating I can see where ur coming from but personally I use something that's designed to heat an enclosure to do that job. Just my 2 cents


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## Snowman (Feb 27, 2014)

There was a thread awhile back. People were showing their handy work in regards to lighting. 

Whilst it was disturbing to see, it was also wildly hilarious to the electricians just how wrong and illegal many of them were. 

Electricity is one of those things where people think because it's working it must be okay. Unfortunately the ignorance or lack of understanding gives many a false confidence with their DIY electrical work. Earthing is generally neglected and correct terminations are few and far between. A bad termination can work for 5 years. Then eventually end in fire. 

It is very simple to get a light to work. Doing it right isn't so simple.


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## -Peter (Feb 27, 2014)

Hmm, an electrician offering advice... should I? Nah, his advice doesn't match up with what I want to do..


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## Gavatron (Feb 27, 2014)

I used very small wattage halogens in my enclosure below. These are used mainly for just lighting the enclosure and are on a manual switch. The bottom compartment uses a caged CFL due to there not being any clear back space for a halogen in the bottom section. My heating is heat cords layed into zig zag routed into the floors and covered with tile.
have you considered using heat cords? They are cheap, low wattage and very easy to have wired together to run off a common thermostat.
Find them on ebay.
That dogs breakfast of cords and timer etc is gone too. I had an eleco wire it all.
View attachment 306255


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## Clarkeyy (Feb 27, 2014)

I understand where your coming from snowman and I have considered the led strips but I much prefer the display and spotlight look of the downlights I know it's a lot of wasted space but I think it's worth it they will all be wired up by a electrician all be earthed I'm going to have vents in the front fans at the back and I'm going to screw cement fibre board above the light to fireproof the timber above the lights . Probably have above around 5 watt globes and using heat cord for heating


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## Ramsayi (Feb 27, 2014)

Snowman said:


> You need 100mm top clearance and 100mm side clearance all the way around.



I thought it was 200mm clearance all around?


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## Snowman (Feb 27, 2014)

Ramsayi said:


> I thought it was 200mm clearance all around?


Nah just 100. Unless it's highly flammable material.


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## Ramsayi (Feb 27, 2014)

I thought I read somewhere clearance for halogens was 200mm above and 200mm side clearance 200mm to insulation.Incandescent 50,100 and 50mm respectively.

With regard to whatever distances are correct are they written for unventilated areas such as bulkheads etc,with the exception of insulation?


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## Djbowker (Feb 27, 2014)

The instructions on my downlights specified 200mm apart.


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## OldestMagician (Feb 27, 2014)

AS3000 specifies 100mm, that's best practice so 200mm just means you're doing better.


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## Snowman (Feb 27, 2014)

Djbowker said:


> The instructions on my downlights specified 200mm apart.


200mm apart is different to clearance.


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## Snowman (Feb 27, 2014)

Ramsayi said:


> I thought I read somewhere clearance for halogens was 200mm above and 200mm side clearance 200mm to insulation.Incandescent 50,100 and 50mm respectively.
> 
> With regard to whatever distances are correct are they written for unventilated areas such as bulkheads etc,with the exception of insulation?



AS3000 doesn't differentiate between lighting types. Just light fittings (luminaire). A recessed fitting with any sort of globe has minimum distances of clearance.


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## Snowman (Feb 27, 2014)

This is the general Australian Standard. The other is IC class which is only NZ. The standards are AS/NZS 3000 these days.


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## Ramsayi (Feb 27, 2014)

That's interesting.So the general AS is redundant?

found the info where I read it from originally..AS/NZS 60598


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## Snowman (Feb 27, 2014)

Ramsayi said:


> That's interesting.So the general AS is redundant?
> 
> found the info where I read it from originally..AS/NZS 60598



That standard is used for testing fittings to ensure they comply with AS.NZS standards. The wiring rules apply to install. So AS/NZS 3000 is the bible as far as how you can install downlights. 
There's a lot more to the standards than just the minimum clearances. eg, locations, requirements, warning signs, barriers, combustible materials and installation precautions where each topic has its own set of regs to follow.


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## saximus (Feb 27, 2014)

What about GU10 fittings that don't recess into the roof but attach to it?


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## Snowman (Feb 28, 2014)

saximus said:


> What about GU10 fittings that don't recess into the roof but attach to it?


They would have to be earthed appropriately. And also be tested to Australian standards they would be installed with minimum distances to walls. They also still come under the many other regs I mentioned such as install locations, combustible materials (wood), general requirements etc.


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