To air cool or not to air cool...That's the question

[LumpStatus]

Hello everyone...

Basically, we got a 10x20 room, completely sealed (except when I open the door of course). Plan on running 4 - 1000w HID lights with ballasts in room. I have more than enough air conditioning to cool the lights wheather they are air cooled or not.

A. Would it be in my best interest to air cool these reflectors?
B. If yes, how much can I expect it to cool the hoods over not using air cooling (IE: how much less will my AC have to run if I air cool them).

I have always air cooled my lights, but that is because I NEVER had air conditioning before. I have noticed that even with over 400cfm going through my lights, when I put my hand below the glass, it is still REALLY HOT.

C. How effective would it be to use the hoods with NO glass whatsoever and rely on my AC 100% of the time? Will this allow more lumens to get to my plants since I have no glass blocking some of the light and no dust/debris building up on the glass blocking even more light?

 

[seebobski]

if you look up in the stickies ac size

3-4000 btu to cool per 1000 watt hps heat load not air cooled
that's 12-1600 btu just for lights
with good duct work separate in and out
you have 10x20 = 200 sf
1600 cubic feet
try maybe 8-1200btu with aircooled try maybe 2400btu if not

you have to think of what heat sources in the room (area grow
in,ballast,fans,dehu, ecc.)that will need to factor in also


do some reading ac sizing is important!!!(it will cost more in the end if not)

bare bulbs no hood

or hoods and ducting with glass is my vote alot depends on grow style

 

[toodles]

I wouldn't advise removing the glass in your fixture. The heat absorbbing glass helps prevent IR radiation from ever getting to the plants. All that heat absorbed by the glass is heat that won't get to your plants.

Running air through the reflectors would help a lot carrying away that heat, but maybe if your A/C keeps temps where you need them, blowers wouldn't be economical?

Keep the glass though. Here's a good explanation why.

Toodles

From the net

"Heat absorbing glass is used to reduce the amount of heat transmitted through an optical system. Heat absorbing glass effectively absorbs wavelengths beyond the visible spectrum. Unlike a hot mirror, which reflects the infrared wavelengths, the heat absorbing glass absorbs the infrared radiation and then dissipates the heat into the air around the glass. Heat absorbing glass can also be utilized as a shortpass filter, in order to pass the visible and block the IR. We recommend using a cooling fan with any of our heat absorbing products to reduce stress associated with excessive heat."

 

[Haps]

I air cool my K's, by rigging fans to blow over them and take the hot air to the exhaust. Works for me.
H

 

[badmf]

First off you can do it either way. But a 400cfm is not adequate to cool 1k's without significantly cooler intake air. Two schools of thought
1. no a/c = better PAR light, but added heat plus distance of light to plants.
2. a/c lites= lower distance (if Elicent 309cfm. Vortex 6" or better, remember static pressure is what moves the air past duct friction, turns etc!) ducting must be as straight and short as possible. What size vent flanges are on your lites if they are 4" you need a large azz set of fans intake and exhaust to really be "air-cooled" if you have newer 6" or really newer 8" then the design is such you can use lesser fans. Best way is to silicon all glass and any perceived cracks etc to prevent in-room smelly air + Co2 being sucked out, not good.
I would K.I.S.S, no a/c lites, osc. fans blowing between lites and plants, watch temps at plant top heights, of course LST to gain more plant to PAR ratios. With a closed room and CO@ added at 1550ppm or > you will love it! Spend the extra $$ on some fine product while you wait for yours to finish!