Lighting converting a hood to a Cree LED

[Ripper]

So I have been bothering the heck out of @Atulip and he has generously been providing me with more information than I could ask for.

So I am thinking of taking a 23" x 17 hood and converting it to a cree led for my 4x4.

I have a few thoughts and would like some input.

My first thought is getting 2 big heat sinks that cover the whole inside of the hood and keeping the glass on. I would then set up an inline fan that drew air only from the outside thru the hood and back out of the tent so it would not be hooked up to the scrubber at all.. (I would have a separate fan for my scrubber ).

any thoughts on if this would create a massive heat issue?

Ps I am thinking of have 4 72v cxb3590 (4000K) and 4 36v cxb3070s (3500k)

 

[Atulip]

Going with a big heatsink, you can almost run them passively cooled, running them with an exhaust is more than enough to keep them icy cool. I'd share it with the carbon filter, no need to have its own fan.

As for the cobs, what watts you planning to run at?

 

[Ripper]

Going with a big heatsink, you can almost run them passively cooled, running them with an exhaust is more than enough to keep them icy cool. I'd share it with the carbon filter, no need to have its own fan.

As for the cobs, what watts you planning to run at?

well I have to talk to you about the watts... I want them to not make the electric bill go nuts.... looking for the bill to go down... also My fan turns off and on from the scrubber based on the heat in the tent.. I use one of these http://www.ebay.com/itm/Inkbird-ITC...844292?hash=item4af722f944:g:92AAAOSwKtlWlJ0- so should I put a couple of pc fans in the hood so there is some sort of cooling at all times?

 

[Atulip]

Depending on what heatsink you go with a couple pc fans would probably do just fine. And I'd run them at 50w each for a 4'x4', should see about a 700w hps equiv for 400w. That'd be .7A for the 72vs, and 1.4A for the 36vs.

Check one of these for an easy prewired fan. They move a good bit of air. (I use one to pull air out of my drying tent into the grow tent)

http://www.ebay.com/itm/120mm-38mm-...627587?hash=item35cc67e503:g:yvUAAOSwZ1lWdJYs

 

[thetreeman]

I guess I dont see the benefit of putting the HS and cobs in a hood, unless you are in a very warm area and want to try to capture and remove all heat from the light immediately. Then it might not be a bad idea....

 

[Atulip]

Makes it protected also. And neater looking. My area has exposed leds and wires flopping out lol.

And economical if you've already got the hoods.

And thinking about higher heat scenerios running 700-800w of cob inside an old hood to light a 5'x5' like a gavita would. You could build an easy gavita killer for $800-900 that way. Cool em all like you would normal hps hoods. Electrical savings alone would pay for itself in 1.5 years @ $.12kwh.

 

[Ripper]

I guess I dont see the benefit of putting the HS and cobs in a hood, unless you are in a very warm area and want to try to capture and remove all heat from the light immediately. Then it might not be a bad idea....

I grow in my garage and it gets warm in there