Heat of HPS lights?

[espo51]

I was thinking of buying a new hps light at the start of my next grow, but I am worried about the heat. I plan on either getting a 200w or a 400w, so the total watts would be either 350 or 550 from hps. I am wondering if I would need to run an inline fan to get the heat out, or if something like a swamp cooler would do the trick. Thanks!

 

[Radio_Dread]

not sure bout a 200w but a 400w you will prob need an inline fan to get your heat out. that is depending on your space of course

 

[espo51]

its around a 2' x 4' space...maybe a little bigger

 

[Widowmaker]

What temp range is the air you would pull in with the fan? What is the current temp range of the room? If you are on 12 & off 12 hours and the lights are on at night the air is most likey going to be cooler.

How high is the ceiling?

:icon_spin:

 

[CAPO]

yes you need air exchange-period; unless you are gonna use co2.
If you use co2 (not recommended with that little of light) you use a sealed hood with vent ports. You could easily get cooled down with a cheap 4 inch inline and a small carbon filter.
Your plants will thank you.

 

[Widowmaker]

:sign0006:
Understand this is not what you asked but here it comes anyway…………To me light is the whole game, everything follows light or supports the growth light promotes. For small spaces I like T5 fluorescent fixtures and use all red spectrum lamps. Quantum Triphosphor Lamps 2900 Kelvin stay brighter longer than normal lamps do because of the Triphosphor coating. From what I’ve seen the red ones have all the spectrum the blue lamps have plus red. The other issue is distance to the plant. A T5 at 2” is 50K Lux and I’m sure your 250W HPS is brighter than that but only the closest parts of the plants will get it. The T5 is 50K almost the whole length of the tube.
See


The HPS is more or less what’s called a point source and the light falls off at by ~75% per doubling of distance. Let’s say your 250W works great at 8” (just a guess) at 16” it’s about 25% as bright. The long fluorescent tubes may not be as bright, but may end up delivering more light to your plants depending on your configuration. The tubes are a line source and the intensity does not fall off as fast as a point source. If the plant touches the bulb you’re not likely to burn. Understand if money is an issue, but that aside you could put three 4’ four lamp fixtures in their 1 on top 1 on each side, 2’x2’ on each end, but just one 4’ will work. I’ve got 2 plants that have a T5 fixture with Blue lamps on one side and a 1000W HPS on the other and the buds that are getting both lights, half and half look the Dankest. Maybe the lighting just makes them look better. Let you know in a couple months when I smoke them.
:icon_spin:

 

[espo51]

thanks for all the help guys, but another question. if i were to get an inline fan would i need glass sealing the light? If so why? cause i was never really sure

 

[Widowmaker]

thanks for all the help guys, but another question. if i were to get an inline fan would i need glass sealing the light? If so why? cause i was never really sure

I believe the thought is that you would use air from outside the room through sealed light fixtures for their cooling and exhaust to the outside. This way you are not blowing your CO2 out of the room.
:icon_spin:

 

[espo51]

ahhhh...ok! thanks for that help. But one last thing, if i use an inline fan and filter i am going to have to run the air out of the room right?

 

[BudBlazer]

ive got a 400 hps in a 4x4x7 tent and i draw from the crawl space and exhaust into the attic. im using a can fan and can filter and pulling through the filter to scrub out smell. i also put a sliding door inline with the intake port because my winter temps were dropping too much.

 

[ShorelineTex]

There are lots of different ways to hook this up. The best way is probably to have an inlet duct coming into the light fixture from the outside of the tent, and an outlet duct with an inline pulling air across the sealed light fixture. This way the light is on a completely closed "circuit" and you can vent your heat somewhere else (attic or whatever). You would need an extra inline to pull air through the tent if you did it this way, but it'll be a lot easier to cool.

With a 200 or 400 and a filter, you can hook up the filter inside the tent, duct it to the inlet of the sealed light fixture, then get a good fan to pull air out the other side of the fixture and duct it somewhere you want to vent the heat (unless you're running CO2, then you wouldn't want to be pulling gas out of your tent to cool your light). This is probably the most cost-effective way to do it in your situation.

You're going to want to at least vent the air to another room so you don't have a heat problem in your grow space, but with a 200 (and maybe even a 400), you can probably vent it inside the house and the AC will pick up the slack if venting elsewhere isn't an option. I've temporarily vented a 600w light inside of a house to a different room in the middle of a Texas summer and the AC was able to take care of it. It'll hurt a bit more when the electric bill comes along, but definitely an option.