Quick question for Led growers

[Damngrower]

I'm enticed by the low heat produced by Led lights but I'm wondering, roughly how much heat do they give off? I know it will vary depending on size, im looking at getting 2 300w viparspectra boards to replace my hps which is too hot for summer growing.

[Obi-Wan]

Those 2 lights will put out about 1/2 the heat of a 400W hps but they’ll only replace a 250W hps in terms of coverage in my experience. The best plants I ever grew were under 2-300W LED’s, 1 viparspectra and 1 GalaxyHydro. 2 of them covering 1/2 of my 2x4 tent. I ran 4 of them in a 3x3 until I realized I was better off with a 400W air cooled hps. I have quantum boards now and they’re great in the summer but they don’t keep the tent warm enough in the winter.

[JDU]

I'm noticing that in my 4x4 veg tent since I dumped the T5s in favor of a Mars Hydro TS1000. 70°F is high anymore..... I have a low hanging T5 I use as a bench & have started leaving it on for the heat.

[SoOrbudgal]

How big's your tent? At one time before i got the 36x36x72 i had 2-450 vipars in there it got warm above 83 i was running all photos so i placed a fan out side the tent to help. I had to adjust the timer to run during night when it was cooler. Really if i had to get new lights and you want alittle heat for winter these would be it. I don't think i ever ran during hot time in summer ( now i am do to need ) but i'm running all auto flower in both tents for now. My smaller tent is 3x3x54? it's got 2- vipars in it also but i can leave flaps open no worries. 12/12 on photos may be all closed up could be to warm without inside fan ?

These newer QB's are sure nice though if i ever need another i would go with those.

[bboyfromwayback]

The quantum boards barely put off any heat and have better coverage. Those 2 300’s in a tent will put off more heat than you’d think they would and their fans are pretty loud.

[JDU]

That's not entirely true. I have about 650w of Mars Hydro in the flower tent & I have to leave the flaps open AND run duct from an AC unit to stay below 84°F in a room that is 70° They definitely DO emit some heat.....
But I hate to think of how hot it would be with anything other than LEDs

[Damngrower]

Sadly more expensive stuff is out of my budget. My tent is 60cmx90x150 so the coverage is spot on and I'm currently using a 250w hps. Sounds like they will still raise the temp in my tent by a few degrees compared to the rest of the room.

[gbauto]

I'm enticed by the low heat produced by Led lights but I'm wondering, roughly how much heat do they give off? I know it will vary depending on size, im looking at getting 2 300w viparspectra boards to replace my hps which is too hot for summer growing.

The amount of heat the pair introduces into the grow is equal to the combined ACTUAL wattage consumed.
Although HPS emits a large portion of its output as infra-red radiation, the total amount of heat is still determined by the amount of energy you introduce into the room.
Watts are watts
Because of no IR, leds can run in the low 80's.

[Gjourney101]

I'm using a 300W full spectrum right now. My temperature stays between 73-78 with tent zipped up. And the fan is fairly loud. Not loud enough to be heard 5 feet away from the room, but when you walk in you can definitely hear it doing work.

[Preston12]

I have a Spider Farmer (SF-1000) in a 2x3x6 closed space and the temperature gets to 80°-82°, while outside it's around 75°. I have three small PC fans hanging around the grow. No intake or exhaust

[Insight]

The amount of heat the pair introduces into the grow is equal to the combined ACTUAL wattage consumed.
Although HPS emits a large portion of its output as infra-red radiation, the total amount of heat is still determined by the amount of energy you introduce into the room.
Watts are watts
Because of no IR, leds can run in the low 80's.

This is true and exactly what I found...

4x4'x6.5' tent.........first had 4- 300 watt viparspectar LEDs drawing a total of about 550 watts. Then replaced with 2-315 LEC drawing a total of about 600 watts. Tent remained about the same temperature with either setup. I believe the 315 LEC's gave me a better yield than the LED's.

I even tried 1 315 LEC and 2 300 watt LED's....same amount of heat.

[Damngrower]

Cool, thanks for your advice everyone!

[johnb1963]

Hello Damngrower, i have a 3x3x6 tent, and i use 1 california light works solar extreme 250, and their UVB light(a must, last 3 weeks of flowering), and my tent runs 4-5 degrees hotter that the room temp.

[changeofpace2014]

Hey D.G - I use 9# 50w bridgelux leds with a mixed spectrum and each one does indeed require a strong CPU fan mounted on a heat sink. The led is taped to the heat sink with electronic caption tape along with a good thermal compound for the led / heatsink. this setup has been successful for 2 grows.

I vent the heat with a 300 cfm fan / carbon scrubber.

my setup cost about 40$ a month in hydro bill and that includes 9 # 50 w led, each with cpu fan, intake fan for the tent and 300 cfm exhaust fan. Pretty good I.M.O..

[NeBoddy]

What kind of yeild are you getting from that setup?

[changeofpace2014]

a pound, give or take.. I do follow Nebula's manifold technique and have been able to keep sativa around 4 1/2 feet maybe 5 ft..