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400watt HPS Heat?

Gaffle

Well-Known Member
I am considering a potential HPS purchase. I am currently using a 300watt led (those fake watts) and everything has been fine, but yield is a prob. Not enough light for a real good yield. Now I could spend more jack on a larger LED, or I could spend less and still get a good amount of light from a 400watter. The trouble with the HPS is heat. My area is under my stairs, so main grow for flower is 3x3. This is not a small confined tent, yet I do not want to battle heat issues. As of right now my led has the room (at canopy height) at 75F max. A larger led will increase heat I'm sure, but I know what I get now so im not scared about that.

In the winter i had a small space heater in my room with temps going as low as 60F in that room. It has no window and is insulated with 1/2in foam. I would not be afraid of HPS Heat during winter, I would lower my space heater, but I am scared of HPS Heat during the summer. I have a 4in inline pulling in fresh air and carbon filter is at top of room.

How hot can a small HPS make a room?
 

marleynme

Member
Upgrade your extraction to 5 inch use the 4 for intake
It will get hotter in there for sure maybe a cool tube is an option ?
I used to run two cool tubes with filter on end of one and fan in the end of the other one in a straight line if worked great although I was using a 6 inch L 1
But cool tubes a thought for u
 

Icemud

Member of the Month: July 2012, July 2014 - Nug of the Month: July 2012
3.412142 BTU/hr = 1W

400W = 1364.8 BTU/hr *approx not including ballast

Using a cool tube or sealed "air cooled" hood would probably reduce that to about 1/3 of the 1364.8 BTU/HR

HPS aren't as "hot" as most people think they are, the bulbs get hot where you don't want to touch them, but LED of the same wattage get just as hot...

wattage draw = heat load to a closed room, when looking at lighting. So no matter the source, LED, HPS, Florescent...if they are all same wattage the all will put out the same heat load on a room for the most part.

I would suggest adding a Ceramic Metal Halide... slightly higher price than HPS, but amazing bulbs, full spectrum, also comes in 400w. (well the new ones are 315W I believe) And make sure to get an Air cooled hood if you go with HPS or MH or CMH...

Also, run your lights at night, not during the day which will help keep the temps low, especially during summer months.
 

Gaffle

Well-Known Member
Thx! The led I'm using is cheap, but not bad. Guesstimate of draw is in the 180s. Sucker is just barely warm under the lights. I'm just trying to get the best bang for my buck. Luckily if I go HPS I have a outlets to use outside of my room. Ballast will sit outside so no extra heat.

Ice, I sure do like those budmasters....
 

Icemud

Member of the Month: July 2012, July 2014 - Nug of the Month: July 2012
HPS and LED equivalent puts off the same heat....BULLSHIT. Most LED growers ive seen on here choose GARBAGE ass lights. KIND LED's are proven Cup winners and the only complaint anyone can have is price. Which, you make back off your first harvest.

I didn't say LED equivalent... watts for watts the heat load is the same. The reason that some can get away with saying "led is cooler" is because LED's are more efficient at generating light, which means less watts are needed. So yes, if you were talking about "LED equivalent" and heat, then the heat would be different. Such as a 60w house bulb and a 23w CFL (60w equivalent), obviously the 60w incandescent light would be about 2x hotter, because it is using 2x as much wattage. IF you compared at 60w incandescent and a 60w CFL with actual draw being 60w, then the heat would be the same. Equal wattage draw = equal heat load in a sealed environment. This is laws of thermodynamics and conservation of energy.

I don't know what other growers using garbage has anything to do with the conversation......

Also, Kind LED are far from quality.... unless something changed with their new models, they are just a rebranded cidley apollo panels. Look up "Cidly Artemis Aquarium" and you will see the exact same thing as a Kind K5, just with different diodes. Kind just buys premade panels from Cidly, has some diodes swapped out to make a "proprietary" spectrum, and then has the cases laser cut with their logo. Its basically marked up garbage..
 

TorturedSoul

Member of the Month: May 2009, Oct 2010, Sept 2017
I am currently using a 300watt led (those fake watts)

IMHO, it is always best to state actual wattage when discussing lighting. Of course, if you do not have access to that number...

The trouble with the HPS is heat.

I have read that cannabis actually grows - and yields - best at a temperature of between 77°F and 86°F, with the top of that range being required for the plants to take full advantage of the 1,500 μmol that is said by many to be the optimum light intensity (for, I am assuming, equatorial sativas, lol). This does, of course, depend on other factors such as having enough CO₂ in the room. But... I take this to mean that - within that temperature range - as one increases the amount of illumination, not only is a slight increase in heat acceptable, it is a good thing. But keep in mind that I'm no brain scientist or rocket surgeon ;) .

HPS aren't as "hot" as most people think they are

You can say that again, lol. I see people complaining that they cannot handle the heat of, for example, a 400-watt HPS so they "went with 400 watts' worth of CFLs instead" and I shake my head. And then, when they end up adding lots more CFLs in order to make up for the poorer efficiency of CFLs so that they can get approximately the same yield that they would have gotten with that 400-watt HPS, lol...

the bulbs get hot where you don't want to touch them

I've told people that 100 candles burning in a small area can heat it up just as quickly - and as much - as one larger fire can, but they just look at me funny. <SHRUGS> I guess maybe it's because they can touch a CFL bulb and not run away screaming (but then they do not use ONE CFL in their grow room :rolleyes3 ).

3.412142 BTU/hr = 1W

I have seen that before. There's one thing that I do not understand, though:

So no matter the source, LED, HPS, Florescent...if they are all same wattage the all will put out the same heat load on a room for the most part.

That's the part that I am having trouble with. Doesn't the differing efficiencies play any part in this at all? Light sources produce two things - they eat electricity and... defecate (lol) light and heat. Right? We say, "A very efficient light will produce a greater amount of illumination than a very inefficient one will (when using the same amount of electricity)." But by the same reckoning, wouldn't that mean that the more efficient light source produces less heat (again, for the same amount of watts)? If... If the amount of energy consumed is the same, then doesn't the total end result have to be the same in each case? And, if so, and one product produces more light... So, well... I'm confused, lol.

I know from reading your posts that you are both intelligent and knowledable about various sources of illumination. So can you explain where my logic(?) is incorrect. If it is? Feel free to dumb it down, as it has been many years since my high school physics class and I seem to have left a trail of brain cells all along the way. I do remember... something about light itself producing heat - maybe when it strikes a surface? I guess it is more that I feel that I once heard someone explain it to me than actually remembering <SIGH>. But... I would have thought that this would only be highly significant with, IDK, infra-red light (I'm thinking of "heat lamps" here). Even IF all wavelengths of illumination are equally significant in that regard, err... Well, the light would have to be converted to heat in order to make heat (huh?) but the heat that an inefficient light source produces as a waste product is already heat.

My head hurts ;) .

Guesstimate of draw is in the 180s.

The product's specifications should state the actual power consumption in watts. But not every manufacturer/seller publishes this information, I guess. Still, they should list - and it ought to be listed somewhere on the actual product - its amperage draw @ a given voltage (110V, et cetera). Since it is a simple formula, you can calculate this. Watts = Amps x Volts .

You can also purchase a product called a "Kill A Watt" that you plug into an electrical outlet and then plug the device you wish to measure into it. Looks like they're selling for between $12 and $25. I wouldn't make life or death decisions that require four-digit accuracy based on one, lol, but I have used them in the past and they seem to be pretty accurate as long as their calibration doesn't get messed up. That shouldn't happen under normal usage, but it is probably a good idea to check one occasionally against a known load. There is a simple - but undocumented calibration method that only requires a certain known load (IIRC, it's 1,000 watts @ 110V but I wouldn't swear to it), so I guess someone could recalibrate one - if it ever became necessary - with 10 100-watt incandescent light bulbs running in series or something, IDK. Anyway, these devices are dead simple to use and have a multifunction LCD display. They'll also show you if you aren't getting the correct voltage at your receptacle.

This is laws of thermodynamics and conservation of energy.

But do those laws take into account varying degrees of efficiency with two dissimilar objects, or do they make the assumptions that the levels of efficiency are equal?

It has been a while since I ran a 400-watt metal halide and a 400-watt high pressure sodium running at the same time in two equal-sized spaces. But I was under the impression that the MH ran a little hotter (and produced slightly less illumination). But, again... trail of brain cells. So IDK.
 

Icemud

Member of the Month: July 2012, July 2014 - Nug of the Month: July 2012
I have seen that before. There's one thing that I do not understand, though:



That's the part that I am having trouble with. Doesn't the differing efficiencies play any part in this at all? Light sources produce two things - they eat electricity and... defecate (lol) light and heat. Right? We say, "A very efficient light will produce a greater amount of illumination than a very inefficient one will (when using the same amount of electricity)." But by the same reckoning, wouldn't that mean that the more efficient light source produces less heat (again, for the same amount of watts)? If... If the amount of energy consumed is the same, then doesn't the total end result have to be the same in each case? And, if so, and one product produces more light... So, well... I'm confused, lol.

I know from reading your posts that you are both intelligent and knowledable about various sources of illumination. So can you explain where my logic(?) is incorrect. If it is? Feel free to dumb it down, as it has been many years since my high school physics class and I seem to have left a trail of brain cells all along the way. I do remember... something about light itself producing heat - maybe when it strikes a surface? I guess it is more that I feel that I once heard someone explain it to me than actually remembering <SIGH>. But... I would have thought that this would only be highly significant with, IDK, infra-red light (I'm thinking of "heat lamps" here). Even IF all wavelengths of illumination are equally significant in that regard, err... Well, the light would have to be converted to heat in order to make heat (huh?) but the heat that an inefficient light source produces as a waste product is already heat.

My head hurts ;) .

You pretty much got it already... when you have a wattage draw you have waste heat and light... since heat is the lowest form of energy, when light strikes a surface it becomes heat as it is absorbed. Therefore if you added up the waste heat plus the heat from the photons striking a surface it would be the same, regardless of efficiency for the same wattage draw. This is why when you turn a light off, the room goes dark, as all the photons quickly absorb into the surroundings. Now physics says this is true in a isolated and sealed enclosure, closed loop system so there is some environmental influence that comes into play as different materials that your grow room are made out of can either allow the transmission of this heat through the surface, or reflecting it back into the grow area, which will influence how a light will heat up a room, even though technically lights of the same wattage draw will produce the same heat load, however the environment will influence how this heat is dispersed. Also if you have plants, which take photon energy and convert it to stored energy or caloric energy, then this would slightly influence the differences between light sources as one light source may be absorbed easier than another... but generally speaking in a sealed enclosure, the lights of the same wattage should theroetically put out the same total heat load in a isolated room.
 

415friendly

Well-Known Member

TorturedSoul

Member of the Month: May 2009, Oct 2010, Sept 2017

TorturedSoul

Member of the Month: May 2009, Oct 2010, Sept 2017
Did the link not show up? It had some posts about BTU outputs of some different lighting setups

Err... Do you see it, upon reloading this thread, lol?

It could, I suppose, have been edited out by a staff member if it was a link to another cannabis-related forum, or to a commercial website which is in direct competition to one or more of our sponsors. But people usually receive a PM explaining why that happened (I think?).
 

Gaffle

Well-Known Member
I bought a 400watt kit with a reflector and bare bulb. The MH at 75% had my room at 82F with the temp takin at small veg canopy. That was too hot for comfort. Sent it back and I went with a different 400w kit with a cool tube. Reflector is not the best but room is small so not worried about my light distribution. I will be happy if i get 80s, as long as the heat isn't directed right at canopy. I was impressed at the amount of light the MH produced. A HID worth of 400watts, wow...
 

TorturedSoul

Member of the Month: May 2009, Oct 2010, Sept 2017
I bought a 400watt kit with a reflector and bare bulb. The MH at 75% had my room at 82F with the temp takin at small veg canopy. That was too hot for comfort.

Ironically, 82°F is pretty much in the middle of the optimum temperature range for cannabis of 77°F to 86°F.
 

Gaffle

Well-Known Member
Ironically, 82°F is pretty much in the middle of the optimum temperature range for cannabis of 77°F to 86°F.

The problem was that 82 was taken low. The light was not at max height, but close. When I raised my gauge the temp obviously jumped. A larger plant at canopy would be questionable. Again, that temp was at 75%, 100% was too hot. With the arrival of cool tube I will kill 2 birds with one stone, it should be cool enough for taller plants and at the same time it will produce enough ambient heat so I may not need a heater during colder months.

I can handle temps that are cooler. I have no equipment for temps that are too high.
 

415friendly

Well-Known Member
Err... Do you see it, upon reloading this thread, lol?

It could, I suppose, have been edited out by a staff member if it was a link to another cannabis-related forum, or to a commercial website which is in direct competition to one or more of our sponsors. But people usually receive a PM explaining why that happened (I think?).

Tapatalk kept removing it, I kept adding it back in. It shows up for me, now, and it is a link to this forum
 

TorturedSoul

Member of the Month: May 2009, Oct 2010, Sept 2017
Tapatalk kept removing it, I kept adding it back in. It shows up for me, now, and it is a link to this forum

That *^&$ing Tapatalk, lol. First it uploads images to its own servers in the United States instead of allowing users to upload them directly into 420 Magazine's own servers where they would be safe, sanatized, and stored in a non-US country - and not it is refusing to post a link to this forum in a post... in this forum? I wonder if whoever wrote that application also helped design the Yugo automobile that was actually slower 0-60 than it was in the quarter mile because it took over a quarter mile to reach 60 mph (talk about a death-trap, trying to merge into 70 mph Interstate traffic at the end of an onramp)?

Anyway... I doubt anyone else is seeing the link that you've tried to post, either. For reference, the quote above is the entire contents of your most recent post in this thread (other than your .SIG), and below is the entire contents of the post in question (again, except for the contents of your .SIG) including some extra (blank) lines:

You might find this old thread useful



Also, you might want to look at the Mars hydro website. They publish the BTU outputs from several of their lights as well as the actual wattage draw so you can maybe make some comparisons or estimates with your current lights

And, yes, I reloaded this thread (again) to make absolutely sure it wasn't somehow serving me an old cached copy of it. If it is a thread/blog/etc., you can post the title of it and one of us will do a search for the thing and post a link to it for you.
 

Croatsan

New Member
I wonder if whoever wrote that application also helped design the Yugo automobile that was actually slower 0-60 than it was in the quarter mile because it took over a quarter mile to reach 60 mph (talk about a death-trap, trying to merge into 70 mph Interstate traffic at the end of an onramp)?

Ah memories, memories...

I'm not so proud to inform you that my former country (Yugoslavia) is responsible for that technological marvel :)
 
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