Adding heat sink to LED in hot weather

[Thighland]

I'm growing in the tropics, using a 1mx1m tent with a MARS FC-E300. It's always too hot here and the light is about 3 degrees celcius above ambient, even with two fans running. While I realize the light will always produce the same heat, I'd like reduce how much is hitting the plants. An idea is to add a lightweight heat sink using conductive glue and then have a duct above it, drawing the heat upwards and straight out of the tent.

I've seen heat sinks with fans attached, however the fans blow downward, I think upward would be better. Does anyone have opinions about extra cooling for LEDs?

 

[Ca++]

Is the ballast remote yet? That might be worth 10%

I see it's a bar light. Can you encase the back of each bar? Something with a C section, like cable trunking.

 

[xet]

SALE HOMEPAGE

www.heatsinkusa.com

 

[Ca++]

Bit bigger than bars, but seems like the same idea. Encase the hot bit to get better control of where the hot air goes.

Could also look at a 1x1 sheet of plastic tent divider. Putting your lights over the sheet and plants under it. I do this with polythene. So it's like having the lights looking in through a window

 

[Thighland]

Thanks for the input. Yes, the ballast is remote, that definitely helps. I think I can attach light heat sink to the rails, but I don't want to push my luck with weight.

I now have two 6" fans, which is enough to suck in the tent sides. My idea was to run ducting over the top of the light, so the hot air would be sucked straight up. Hopefully with the extra heat sinks this would help.

Another idea was to increase the ventilation at the bottom. I'm in tropical Asia, it's either hot or very hot.

 

[Ca++]

I presume your tent is the hottest thing in your room? Have you insulated it, and the exhaust work, to ensure the heat actually leaves?

 

[Thighland]

No, it's not insulated, but I would have thought insulation would have kept heat in? The room it's in is very open, heat can't accumulate.

 

[Ca++]

Insulation is probably not applicable in your case. For most people, heat escaping the tent though lack of insulation, is heat destined to warm the room further.

If heat leaving into the room isn't a problem, then a fan pointed at the tent can very useful.

 

[troutman]

I set a small fan pointing upwards so it blows across the underside of my
SF4000 LED lights so the heat will find it's way to the top of the tent faster
where the inline fan ducting can take it outside.

Running the lights at night may help if daytime is already very hot.

 

[exploziv]

I usually run some pc fans right a bit under the light, but above the canopy. Is a way to make air go between them and separate the hotter space above from the cooler below, while also slightly moving air over the lights and canopy. Taking the hot air from the top part is also very important, you want your air port for exhaust to draw air from near the ceiling, where air is hotter. Also make sure the air that comes on intake is fresh cooler air, and not same or mixed with the one you are exhausting.
Then you can take out the driver, if you didn't do it.
3C above env. is not much, and many would probably call that PERFECT, I would just run the exhaust a bit more powerful and you can make that work, before having to invest too much to change or add to the light heatsinks.

 

[Three Berries]

You could put a false ceiling in the tent with the light body part of that. This should keep most of the heat on the up and out other than radiant.

 

[Ca++]

White bit is polythene tied to the posts
The air from the lights, never gets to the plant

 

[Thighland]

Thanks for the replies. Yesterday I added ducting from above the lights to the top of the tent. There was maybe a slight change in temp. Then I left the tent door open, which didn't seem to do anything

While the polythene idea may work, I think the heat may be radiated from the lights and there's not much I can do. As I can grow legally here, I will mainly use the lights for veg, which was my original intention.

 

[Ca++]

Plants grow there outside, in the sun. I can't imagine it being too hot in a shady room, with an LED panel. If the idea it's too hot comes from books, the answer is often to buy another book

 

[Thighland]

Plants grow there outside, in the sun. I can't imagine it being too hot in a shady room, with an LED panel. If the idea it's too hot comes from books, the answer is often to buy another book

I tend to agree, but with the sun being free and reliable I think veg under lights and flower outside is the best option. We have some cooler weather coming up, so I'll probably be able to flower indoors during that period, but after that it's pushing 40 in the shade.