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Heat from led panels and downlighters

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Mrs C

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We are thinking about using led panels and downlighters on our kitchen ceiling, but instead of insetting them into the ceiling instead surface mount them. Getting at the ceiling from above to do it properly is too painful.

I want to mount them in some sort of wooden frame so that they look like they should be there.

Do I need to worry about heat I.e. would I need something between the edge of the panel and the wood? I know the led bulbs don’t get hot, but can’t find anything about the panels.

Thanks
 

MikeG.

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No, don't worry. Lighting plenums are often suspended on chains so that they can be accessed, and the gap above them is more than enough ventilation space. As you say, the units don't generate much heat, and their shrouds are designed to cope with whatever heat they produce.
 

rafezetter

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Droogs":u1zy2kkm said:
Have a look here for some ideas that will tie into what you are trying to do. a very interesting channel actually

https://www.youtube.com/watch?v=8JrqH2oOTK4
Wow that is amazing - My fathers house has a spot at the end of the hall where we had been considering building a light box tunnel from the roofline, down through the end of a loft conversion to the next floor down - which would not have been simple at all - but this? Simplicity itself.

And our upstairs hallway as it has no external windows, just has low energy lights on 24/7.

And my work area could use a couple of these.

and my shed.

In the comments people suggested adding an arduino to make a "sunshine alarm clock" - I'd also say it could be linked to a PIR for hallways at night for children going to the bathroom etc etc.

Keep an eye on facebook marketplace ppl !
 

Eric The Viking

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I recently helped a friend fit one, 4ftx2ft, in the kitchen of a house in California. It was designed for surface mounting on a ceiling, and had a neat bezel. The back of the panel was a zinc-plated steel sheet, which served both as strengthening and heatsink.

I found only two issues:

1) the condition of the 1940s wiring (and those horrifying wire nuts - don't go there!),

2) the mounting system required pretty accurate hole placement on the ceiling - this is harder to do than you might think, especially if your head no longer tilts up as it should!

To cope with (2), you need to know what's above the ceiling with some precision. Most sparks just lay cable for lighting where it will fit, as that is far quicker than setting it out in straight lines parallel to the walls (and the latter is usually unhelpful anyway). If it's gypsum board (plasterboard) or similar, you have fixing screws along the joists, concealed by plaster. If lath they will be long tacks. These you can find with a metal detector, and you can also probably map the route the cables take. As you will be drilling for fixings, this is important. I would mark what you find on the ceiling in soft pencil, so it's unambiguous.

Then there is the ceiling construction: if lath and plaster, it isn't flat. Panels don't bend, and anyway they do need to look neat, so you will probably have a fairly awkward scribe to do.

Finally, on the one we had, the only cable entry point was dead centre. This was awkward for various reasons: obviously the ceiling rose was _not_ dead centre, but not least the difficulty of connecting it up before the mountings were fixed.

I had limited time and limited resources available, but one thing that would make this much easier would be thin lighting flex. that would fit behind the panel, say 1 metre extra, to allow you to manoeuvre it.

LED panels don't need much power (e.g. 60W is only 0.25A at 240V), so the heating effect spread over 8 sq ft is tiny. You don't need heavy-duty flex, but three core (so you can maintain the earthing) is sensible.

I've no doubt there are better panel designs out there (and ours was made for the US market anyway), so if you haven't bought it yet look for one that gives you the easiest fixings and cable entry options, or room for flex to be hidden behind it.

HTH, E.

PS: If you can't get all the fixings into the joists, I think "cavity fixings" such as "Intersets" are perfectly strong enough for that application. Obviously use the ones that allow you to remove and re-insert a machine screw or woodscrew, otherwise you can't do a test fit! You can also wood-glue blocks or plywood plates on the ceiling (above, out of sight) over your anchor point, and screw into those - that's really strong too. I've done extractor fans that way, to protect the plasterboard from crumbling.
 

sunnybob

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Just a point to make... the leds dont produce any noticable heat, but the supply transformer does, so dont pack it into a cramped space.
 

Deejay

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It's not the heat generated by the panel that's the problem, it's the integrity of the ceiling in the event of a fire.

Fire rated panels will slow down the spread of a fire up into the floor above.

Google 'fire rated LED panels' for chapter and verse.

Cheers

Dave
 

Geoff_S

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What a great idea!

I am seeing my TV in a new light.

But it's fascinating, so much so that I found these

https://www.ledkia.com/uk/buy-basic-ult ... gJqBvD_BwE

Are these the sort of things you are looking at Mrs C? They have solved a problem for me. I wanted to fit downlighter in the top of a kitchen cabinet, but didn't want to see the gubbins on top. These are just the job.
 
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