New 315 LEC too hot

[PuravidaC]

Hey gang, need some advise. Just finished expanding my grow space and fired up new 315. Wow!! Unbelievable light but big problem! Temps climbed to 97 degrees in a matter of a few hours! Can different lamp manufacturer's bulbs put out different amounts of heat?
New set up specs:
Grow space- 2.5'X3.5'X6.25' (not very big but serves my purpose)
light- 315 LEC
exhaust fan- 4" centrifugal (190 cfm)
Intake is 4 times larger than exhaust, still have good negative air pressure and blowing out hot air like crazy. Haven't install fans in the grow space yet, too jacked up to see new light! Really confused. When I checked out a 315 at local hydro store I couldn't believe how little heat it generated. Certainly no more than my old CFL set up (265w actual) that controlled heat easily. I know there are several of you that use LEC, what say ye???

[abadtrip]

A fan moving air will bring it down a little your space is bigger than mine I have a 315 my heat was up there I had a crappy exhaust fan upgraded to a 260cfm and added a 10 inch fan in the tent moving air I have it on low but the bigger blades do a good job of moving more air slowly

[PuravidaC]

Yea, I wondered if I could solve issue with larger exhaust fan...

[Sammy]

I purchase the air cooling kits for both of my Phantom 315 a little Overkill but no heat all heat exhausted out of the room.

[PuravidaC]

Are you talking about a closed, ventilated hood? Haven't seen the air cooling kits.

[Sammy]

Yes it's an add-on for the Phantom 315 consist of a glass a couple of hinges screws of course and weatherstripping and 6 inch adapters.

[Sammy]

I'll shoot you a better picture tomorrow if you'd like this is an older one don't know if you can zoom in and see.

[PuravidaC]

Interesting. I have read that glass will block LEC light output by 10%. I have a Sun System light and not sure if they offer the kit but will research on line. Got close to $500 invested in expanded grow space already so really bummed right now!

[Aloner]

I had read that about glass, too.

[abadtrip]

I was under the understanding that the glass will block the uvb light that the bulb puts out.

[Sammy]

I'm sure it hurts the light a little I doubt it's 10%even with the air cooling kit still grows the freaking prettiest bud I've ever seen. Still can't get lights any closer than 21 or 22 inches pretty intense light.

[Sammy]

Sonnyhead, you don't get any Leaf curling or heat stress at that distance, I had mine lower but my black Dominion's didn't seem to like it very much however the green crack acted like it was turbo charged obviously difference between sativa and indica. What type of plant or what strain are you growing that close to the light just curious.

[Sonnyhad]

I'm growing mostly indicated. And I haven't had a problem so far!

[PuravidaC]

I added a fan to "stir" air in grow space and it helped alot but temps still get to the mid 80's with exhaust fan running full speed. That is marginal so I think I will bite the bullet and get an air cooled hood too (in for a penny, in for a pound)! That way I can lower speed on exhaust fan, which will be quieter, and be able to lower temps during flower. I remember being told when I first started growing to just jump in because I would learn from experience and man, isn't that the truth!

[Sonnyhad]

The ballast gets a little warm on top so a fan would be helpful.

[PuravidaC]

I agree but I need to bring temps down 20 degrees. Just started "dry" runs to get new area dialed in. Nothing growing now so not in panic mode... yet!

[Sonnyhad]

I hear that! Better to get it figured out now than when it would be a panic situation! Lol

[PuravidaC]

Stopped by local hydro store this morning and they have a Sun System air cooled hood. It is for hps light but they have an adapter for the cmh bulbs. Do you think it would lower grow room temperature 20 degrees? The hood costs the same as a bigger exhaust fan and I don't want to throw good money after bad!

[PuravidaC]

I have room for larger tent but stealth is high on list for me. Got some straight neighbors that like to drop by and borrow tools. Having them walk by a grow tent would diffently blow my cover! I have built a "hidden" area for grow space and can't make it any larger without major renovation. This was supposed to be a hobby for me in retirement!!! 😆

[Sonnyhad]

That sucks, because you really want the head room. Maybe move the tools! Lol

[PuravidaC]

Roger that! Or maybe just go back to CFL! I've had several successful CFL grows but I guess it's just our nature to want to improve!

[abadtrip]

Have u got a circulating fan in there with out that fan moving air inside the tent my temps were around 92 with out moving air inside your tent u may not be exchanging all the air inthere and getting stagnant air thats just heating up.my exhaust fan is 260cfm 4 inch with a charchole filter I have a 8ft flex duct that I use to vent into the hall

[abadtrip]

Also what is the temp in the room u are growing in

[PuravidaC]

Temperature of room drawing return air from is around 70. Haven't put oscillating fan in room yet, too excited to see new 315 fired up. I figured it would help with high temps but not lower 20 degrees. Thermometer located at 5' above floor, above light was in low 80's but the other one placed directly below light, about 2' away was at 97.

[abadtrip]

Put a fan in there and see what happens u will be pulling the cool air up from the bottom and circulating the hot air around mixing so yea I might bring it down quite a bit

[PuravidaC]

An oscillating tower fans is (was) the last thing on my list but I will try any fan to see what effect it will have before spending any more money.

[PuravidaC]

Crazy thing is the temperature is higher down low (and under light) than it is higher in the grow area, above the light but I still think you are right that I need to stir the air inside the grow space.

[abadtrip]

Yea I am sure u have a fan any fan just get that air moving just don't do what I did and drop it on your plant it makes for a very sick felling in ya gut

[PuravidaC]

Thanks abadtrip, your suggestion seems to be spot on! I stuck a window fan in grow space on low setting and temps seem to be holding at 79-80 AND humidity isn't dipping as low either! Moving forward with getting a smaller (12")
oscillating fan to see if results stay the same! Much cheaper than a new air cooled hood!! Really looking forward to growing with 315 (and yes, I diffently got a minute!) 😎

[abadtrip]

I went through the same thing I am glad i could help

[Weed Pharma]

When selecting any light you have to consider the number of btu's it will generate.
That's the only thing that stopped me from buying a Viparspectra because, they could/would not, tell me the amount of btu's it generated- Lazy customer service rep that was more of a salesperson.

As I recall, the 315 generates about 1,200 btu's an hour (I like that light) and you will have to offset that one way or another.

That's about 2-3 times the amount of heat (btu's) I can compfortably have (20"x36"x63" flower tent), as large fans would be too noisy in my condo.

[PuravidaC]

Yea, I didn't get into specifics on the 315, just did a hand test on display at hydro store. What lights are you using?

[Weed Pharma]

What I use is listed directly above the grow journals on my posts.

[PuravidaC]

Sorry...

[Aloner]

My understanding is that you want your exhaust CFM to be higher than your intake CFM. Anyway, that was my takeaway from watching Everest's videos on setting up a filter/exhaust fan. I'm getting my first tent together and just bought my exhaust system. I haven't gotten an intake fan yet because I'm not sure I'll need one -- if I'm incorrect I'd love to know before I blow money on the wrong size fan!

[DrPhoton]

No i cannot, sometimes i do. But usually i will go into more detail than i need. I just prefer it that way.
I have edited my previous post so i would suggest a reread. However to sum it up.
The size of the passive intake is dictated by the volume of air inside a room. More space means the ventilation system needs to process more air to maintain the recommended air replacement rate. The adjustment of the passive intake is to maintain ideal negative pressure.

There are formulas to calculate the passive intake size based on flow rate and room size. However i have none on hand.

[Aloner]

lol still pretty inscrutable but thanks for taking the time!

[DrPhoton]

No worries, perhaps you might want to learn about temperature and pressure, and the physics of it. Getting your head around how the air molecules are effected by such factors, really helps you understand pressurization and the coherence of the molecules.