The Luxor hood by Sun System

I purchased four of the Luxor hoods and am having an impossible time cooling the room. I understand the theory behind the sealed light box but, the hoods are like heat lamps in my grow room. My room is 11' x 10' x 8' with four Luxors (1000w). The Luxors have 8" rigid ducting with cold air intake pulled from outside the room by a 1019 cfm 10" MaxFan. Inside, the room is vented by an 8", 792 cfm can fan that pulls through an 8" Phresh Filter and has an ACTIVE 6" can fan intake. After the lights have been on for a few hours, the temp in the room steadily climbs into the low - mid 80s. I love the theory behind these hoods but, with almost any other sealed hood on the market I wouldn't be having heat issues. I can't recommend them based on everything I have tried.

Pics?

This is one of the best rated air-cooled hoods on the market. And the number one reflector in this test.

http://www.greners.com/reflector-test.html

From your description of ventilation I also see no reason why your temps wouldn't be a bit lower. Your cfms for that size of room are a bit low(at 110 square feet you should have 1100 cfms exhausting), but you already have your lights exhausting separately so I would think the 800 cfm exhaust would be enough. How much air are you pumping into room and what is the average temp inside and outside of home when you took temps of grow room?

Do these hoods have a EX39 type
Socket or just a regular E39?

Boost the size of your inlet or outlet fan. Wrap insulation tightly around the outside of the hood. ( the silver bubble wrap stuff)

Did you say rigid duct work? Wrap your duct work also. Then all you can do is mess with air volume and maybe lower intake temperature. That is a ton of heat to move. I bet an HVAC guy could figure it dead nuts for you..but I will try.

1.. If your four hoods are all ducted in series... try venting them two at a time. As far as cfm goes 800 on each one will work.
2.. You are getting a huge pressure frop across the 6" intake, open that to the 8 inch as all the rest is. that may help by itself.

PS..try number 2 first because it is the least expensive I would guess.

I second increasing the intake first. Your creating a bunch of negative pressure which just sucks in rated air from your house.

Put it this way...I have 1400 cfm intakes and exhausts (dayton blowers 11x8 opening..$150 ebay) cooling an 8,500 watt flower room. When they kick on, it takes about 10 minutes (or less) to cool the room three degrees.

Outside air is around 55

It's all about the flow.

TheHarvestConnoisseur said:

I purchased four of the Luxor hoods and am having an impossible time cooling the room. I understand the theory behind the sealed light box but, the hoods are like heat lamps in my grow room. My room is 11' x 10' x 8' with four Luxors (1000w). The Luxors have 8" rigid ducting with cold air intake pulled from outside the room by a 1019 cfm 10" MaxFan. Inside, the room is vented by an 8", 792 cfm can fan that pulls through an 8" Phresh Filter and has an ACTIVE 6" can fan intake. After the lights have been on for a few hours, the temp in the room steadily climbs into the low - mid 80s. I love the theory behind these hoods but, with almost any other sealed hood on the market I wouldn't be having heat issues. I can't recommend them based on everything I have tried.

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Your problem is what is called air roll from static air pressure drop , Ok baer with me ,I will try to put it in terms you understand first you have to understand that air is not a solid like liquid (water= plumbing) and air moves under static pressure in air we calculate using either (equal friction method or velocity reduction method.to find correct duct size to a particular layout (design)


what is going on in your case is the 1019 cfm of air is moving through 10 inch duct witch is about 100 sq inches = only 500cfm, now when the air hits the first hood, the sq inches of space in that hood is more then 100 sq inches , so what happen is you have dramatic static pressure lost , and the air will naturaly take on a roll effect inside the sealed light enhancing the staic pressure drop,as the air pasess through each light the loss of static pressure increases and the roll become slower and slow as it moves down the line.

When air is moved through a confined space square,rectangle,round , it naturaly spirals ,this natural movement of is easly put in to a roll configuration if not ducted properly

The main problem with these light manufactures is they put all there efforts into the light reflection and tell you all about that,but they lack the correct instructions on duct and fan sizing, correct duct installation in general. I am in the process of fabracating some hood in my shop for testing for my room ,so been reading a lot here on light choices ,what works and what dont .as far as reflection and bulb placment in general.

One thing that no-one ever mentions about hoods is they get dirty and degrade (oxidise and/or lose their shine and lustre) very quickly - especially the glass-enclosed, air-cooled hoods. Even if you meticulously wash and shine them every grow - and let's face it, how many people do that? - those 75% efficient reflectors soon become 60%, 50% effective. (Only about 25-30% of a horizontal bulb shines directly on to any given grow - the rest is reflected by the hood.)

With a bare-bulb vertical grow, you simply change the bulb. If you really want to maximise your vertical grow with a reflector, hang your bulb about two-thirds up the height of your plants, and then hang a chinaman's hat-type reflector just above the top of the plants.

A bit like this, but with the bulb hanging right down into the plants and the reflector hanging over the top of the whole grow. You can duct the heat away through the hole in the middle of the reflector:



But it's hardly worth the hassle in my view, as a more efficient way to make use of the light is to bend and train the tops of your plants in towards the middle - over the top of the bulb - so that they almost completely enclose the vertical bulb in the middle. Just imagine a cone or bullet-shape standing on its end, with all your plants around the outside, growing up and bending in towards each other, touching in the middle towards the top. Of course, you need to leave a shaft of space at the top for the hot air to escape, and if it's really hot in your grow room, you won't want to bend your plants in too much or they will burn.

It's a bit like I do with my haze grows. This isn't the best example (I had already harvested the plants behind this one), but it's the best photo I have at the moment:



I basically try to completely enclose my bulbs (I use 2x600w) with my plants using the cage around them.

That is a good way to grow for sure. Allot more training and what not, but excellent use of light.

Reflectors are not that far behind total light basking the plants however. A hood surface is 98% reflective, so your not loosing much light at all. The plus side of a reflector is that the focus and reflect all that light down towards your plant. No light is wasted at all.

Many ways to grow buds, all have their merits and trade offs. But back to the actual point of the thread... Any luck fixing the problem? The flow description above is spot on. My solution was to insulate your room from all the radiant heat coming off the reflector. There is so much fucking metal on those things...they act like a big radiator.

When I tapped up my hoods with bubble wrap, the surface Temp went from like 98 to the ambient temperature of the room. I have allot of hoods in the new room so just decided to increase the size of my cooling system instead.

Good luck

big fatjoint said:

Buy one that has the light horizontal not vertical if you are going to use this type of hood!
Horizontal hoods put out more light than vertical burning ones this is fact!

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as quite a few others pointed out. uh, no. http://www.greners.com/reflector-test.html

Koladog said:

I own both Luxor and magnum. Both great, Luxor concentrates light magnum spreads it out. Luxor is very impressive super bright.

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I have several "ochos" I like em but for the seal leaking. Thinking bout trying some luxors sometime.

Both the Luxor and the OG look awesome, I found this video..it was made by sunlight supply (Luxor) so hardly impartial but it's still interesting.

[video=youtube;2zVzgPPDTsE]http://www.youtube.com/watch?v=2zVzgPPDTsE[/video]

big fatjoint said:

Buy one that has the light horizontal not vertical if you are going to use this type of hood!
Horizontal hoods put out more light than vertical burning ones this is fact!

Click to expand...

LOL, I missed that one. I love when people so emphatically believe they are right... and they are in fact, not.

S.S Loxur has a real nice air flow design ( Double diamond design )nice airflow transitioning compared to what I have seen. def did there homework there ,but was wondering how hot the glass gets.

dont see the need for using more then 250-300 cfm for this light , with this design you can move air to fast and the cool air wont be able to transfer the heat load , So this is one of the cases where more is less.

legallyflying said:

That is a good way to grow for sure. Allot more training and what not, but excellent use of light.

Reflectors are not that far behind total light basking the plants however. A hood surface is 98% reflective, so your not loosing much light at all. The plus side of a reflector is that the focus and reflect all that light down towards your plant. No light is wasted at all.

Click to expand...

Not quite true This is the vertical forum, so I'll just add one more post and leave you guys alone . . .

When light travels, its lumen output is recuced by about a quarter for every doubling of distance (exponential). When light reflects off a hood, it has to travel double the distance to reach the tops of the plants. So reflectors will never be as efficient as direct light. This is one of the main advantages of vertical growing over horizontal growing. Draw a line directly from the bulb to the top of the reflector, then down to the top of the plant, and you will see what I mean. You may think you can simply place the hood closer to the plant, but the design of the hood limits how close you can get it. And with an air-cooled vertical bulb, you can get your plants very close to the bulb itself.

Remember, a vertical bulb with plants placed around it is already shining most of its light directly on to a plant, so is already 80-90% efficient. Even the best hoods are only 70-75% efficient. The proof is in the yields: horizontal growers are happy with 1lb per 600w. I yield 1.5lb per 600w every time and often push 2lb per 600w when I monocrop.

It does not have to travel "double the distance". The other thing your forgetting is that unless you have plants in a perfect circle around the bulb, that percentage of light is wasted. I'm not saying that vertical doesn't rock or anything, but this whole notion of light being "wasted" or soo many less lumens are hitting the plant is nonsense.

I do know one thing though... two pounds per 600 my ass dude. That picture you posted earlier is NOT a 2 pound plant, and you have TWO 600 watt bulbs in there. I have witnessed 2 lb plants many a time.. and that isn't one of them.

Oh dear. Do you think that was the only plant in that grow?

Well, if your "ass" would like to get confrontational, I'm happy to oblige. Four pounds is 64oz. My highest yielding haze was 15oz - most average 10-12oz - and I can fit six of them around my 1200w set-up. As I said, I don't monocrop, but the yield before last consisted of three hazes totaling 32oz (9oz, 11oz and 12oz) a Swiss Bliss of 8oz, a Sensi Star (7oz) and a Sweet Tooth x Sensi Star (6oz). That's 53oz from one 1200w grow. And that's not even my highest yield, which was 56oz some time ago. I average 48oz (3lb) or more each 1200w grow.

But hey, do I sound like I care whether you believe me or not? I'm here to help people - not brag.

Now let me ask you a question or two. Where do photons come from and where do they travel? Light is energy converted to radiation (heat is also radiation). Once photons leaves the sodium element where they are given off they travel in all directions. In a hood, that means the photons at the top of the element travel upwards, hit the reflector, and then travel downwards.

Are you with me so far? Not that hard to understand, is it?

Once those photons have travelled up to the reflector, then down past the element where they originated, they continue to travel down towards the plants. Those photons have now travelled twice as far as the photons emitted from the bottom of the bulb which have not been reflected.

Now what is a photon? It is an elementary particle that must travel through a medium here on earth (air/atmosphere) made up of mostly nitrogen and oxygen molecules. When photons hit those molecules, they are absorbed (causing the air to heat up as it absorbs the radiation), or bounced.

And this ^ is why a point of light gets weaker and weaker in our atmosphere, but will travel almost infinitely in a vacuum, such as space.

Now my plants might not be in a "perfect circle" but if you know what a scrog is (I'm assuming you do), then you will know that a vertical scrog is no different to a horizontal scrog and can be used to maximise light absorption (photosynthesis).

Sorry mate, but physics and chemistry are on my side. They could be on your side, too, if you would let them . . .

But like I said, you guys carry on with your reflector discussion in the vertical forum. That's obviously what you're interested in, so each to his own.

big fatjoint said:

Buy one that has the light horizontal not vertical if you are going to use this type of hood!
Horizontal hoods put out more light than vertical burning ones this is fact!

Click to expand...

hahahaha no they don't ...where do you get your info from

Prawn Connery said:

But like I said, you guys carry on with your reflector discussion in the vertical forum. That's obviously what you're interested in, so each to his own.

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this is a thread about a vertical hood.... and i don't see where it states you cant post about hoods in the vert forum.
you make it seem like a bad thing

and yes, people will grow the way they choose.

A "vertical hood" is not "vertical growing". Hoods and reflectors don't really have much place in vertical growing - if you understand the concept of vertical growing. Which, I assumed, was the point of this forum: to explain and discuss vertical growing techniques. I don't have a problem with anyone using a hood or growing any which way they like. But there seem to be a few myths about vertical growing versus horizontal growing - myths perpetuated in this thread - and so I simply pointed them out.

One member seemed to take this personally. But it was obvious he knew nothing about my set-up and/or simply didn't understand it. If you want to learn about vertical growing, then people who grow vertically - and have done it for many years - can help. If all you want to talk about is hoods and horizontal growing, I would have thought the Indoor Growing section might generate a bit more on-topic interest.

But it's a free world. Carry on.