More heat from bulb or ballast?

Hello everyone,

Tried finding the answer to this question on here but could`nt find anything so will ask here.

Im getting a 400w dimmable HPS/MH setup with ballast. Could anyone tell me, which produces the most heat, is it the bulb or the ballast? if the ballast does contribute a lot to the heat build up, i will install it on the outside of my grow area.

Also if i adjust the ballast down to 50% power which will reduce the bulb to run at 200W, will it only consume 200w of power or will it still consume 400w? and will it kick out less heat than having it run at 400w?

Again, thanks as usual for any info

The bulb gets hot as fuck cmon bro. 400 watts in that tiny glass! Anyways, put the ballast outside anyways. It does have a bit of heat.

I've had my Apollo 400w dimmable ballast since sept. Never once has the ballast gotten hot at all. Either way I keep it on a slab of concrete.
If you use it at half or any other setting I think most ballast still use around 20-40 more watts then what's indicated.
So a 400w really uses around 420-440w. Putting it at half setting would be around 220-240.
Something like that. Might be a little higher but not too much.
Also if your ballast does get hot it should come with an internal fan. Make sure you mount that up vertical so the heat exits your ballast at the top. Heat rises so keep that in mind if you get a cool tube for your bulb which will be ridiculously fucken hot.
You want your cool air to be drawn in from the bottom and the hot air to exit at the top wether it's your vent system or cool tube.
How big is your space?

Sali-D said:

Hello everyone,

Tried finding the answer to this question on here but could`nt find anything so will ask here.

Im getting a 400w dimmable HPS/MH setup with ballast. Could anyone tell me, which produces the most heat, is it the bulb or the ballast? if the ballast does contribute a lot to the heat build up, i will install it on the outside of my grow area.

Also if i adjust the ballast down to 50% power which will reduce the bulb to run at 200W, will it only consume 200w of power or will it still consume 400w? and will it kick out less heat than having it run at 400w?

Again, thanks as usual for any info

Click to expand...

Yes 200w is around 10-15 degrees less hotter then 400 with my cooltube. Idk bout a bare bulb though.

VSFLESHnBONE1 said:

I've had my Apollo 400w dimmable ballast since sept. Never once has the ballast gotten hot at all. Either way I keep it on a slab of concrete.
If you use it at half or any other setting I think most ballast still use around 20-49 more watts then what's indicated.
So a 400w really uses around 420-440w. Putting it at half setting would be around 220-240.
Something like that might be a little higher but not too much.
Also if your ballast does get hot it should come with an internal fan. Make sure you mount that up vertical so the heat exits your ballast at the top. Heat rises so keep that in mind if you get a cool tube for your bulb which will be ridiculously fucken hot.
You want your cool air to be drawn in from the bottom and the hot air to exit at the top wether it's your vent system or cool tube.
How big is your space?

Yes 200w is around 10-15 degrees less hotter then 400 with my cooltube. Idk bout a bare bulb though.

Click to expand...

^^ Good advice.

^^ lol AND LOOK OUT FOR SNAILS

VSFLESHnBONE1 said:

I've had my Apollo 400w dimmable ballast since sept. Never once has the ballast gotten hot at all. Either way I keep it on a slab of concrete.
If you use it at half or any other setting I think most ballast still use around 20-40 more watts then what's indicated.
So a 400w really uses around 420-440w. Putting it at half setting would be around 220-240.
Something like that. Might be a little higher but not too much.
Also if your ballast does get hot it should come with an internal fan. Make sure you mount that up vertical so the heat exits your ballast at the top. Heat rises so keep that in mind if you get a cool tube for your bulb which will be ridiculously fucken hot.
You want your cool air to be drawn in from the bottom and the hot air to exit at the top wether it's your vent system or cool tube.
How big is your space?

Yes 200w is around 10-15 degrees less hotter then 400 with my cooltube. Idk bout a bare bulb though.

Click to expand...

Nah not using a cool tube, they are very long and won't fit in my area, it's an open reflector, which I may have to cut down when it comes so I got more room around it for heat ect. Do you think the area is to small? It's summer here but in my storage it's always cool/cold not hot or warm at all. You think SOG will be beneficial to keep height down or does that mainly apply to using CFL lights?

I have 2 pc 120mm fans for in and outtake which seems to have some good pull on it and will add a small desktop sub fan to the room once I start. Cheers guys for your input

SPLFreak808 said:

The bulb gets hot as fuck cmon bro. 400 watts in that tiny glass! Anyways, put the ballast outside anyways. It does have a bit of heat.

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Tiny glass? You mean a cool tube? If that's what you mean, I'm not using one of them, it's one of them open wing reflectors. Not ordered it yet was originally gonna use CFL but thought with all the bulbs I need to use, the cost is almost equivalent to buying a 400w hPs, so thought stuff it il go with the hPs. Also I think the heat would be around the same and the wattage. The lumen output and PAR is way higher than CFL so kinda made sense. But I have no idea how hot either bulbs would get, hence the Reason I'm asking. Thanks for your reply mate.

Sali-D said:

Tiny glass? You mean a cool tube? If that's what you mean, I'm not using one of them, it's one of them open wing reflectors. Not ordered it yet was originally gonna use CFL but thought with all the bulbs I need to use, the cost is almost equivalent to buying a 400w hPs, so thought stuff it il go with the hPs. Also I think the heat would be around the same and the wattage. The lumen output and PAR is way higher than CFL so kinda made sense. But I have no idea how hot either bulbs would get, hence the Reason I'm asking. Thanks for your reply mate.

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No i mean the bare bulb itself is hot as fuck. The ballast is just an amplifier, it will create some type of heat but its not too bad. Anyways id keep it out of the room if possible. Just use the hps. If it gets too hot, pull in cold air.

Sali-D said:

Do you think the area is to small?

Click to expand...

In your other thread you mentioned (a little late) that stealth is a priority. I haven't seen that mentioned here.

I continue to believe HID will be too much for your 4' tall space unless you keep them short, scrog(?). You could use gentler, more distributed light and have the ability to grow taller plants (if that ever was desired) using the entire height of the cabinet.

But, even accepting the height limitation: you're going to have to move more air. Your stealth cabinet will risk sounding less stealthy than running some efficient LED at 20-30w/sq ft. The HID ballast will also make a sound outside the stealth cabinet.

If stealth is a priority, to me heat management would be a priority.

What ever you do I would advice for the ballast to be outside the tent

Labs Dexter said:

What ever you do I would advice for the ballast to be outside the tent

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hi mate, im not using a tent, its a space i converted into a rectangular box. 2 walls are concrete which are very cold to touch and the other wall and roof is wood including door. Im thinking lot of heat would be absorbed into the two concrete walls thus keeping heat down considerably. plus everything painted white which doesnt create heat like foil...to my belief anyway. two intake and out take fans installed 120mm and would put an additional small fan in for circulation ect.

Have a look here:

http://i67.tinypic.com/2nve909.jpg

az2000 said:

In your other thread you mentioned (a little late) that stealth is a priority. I haven't seen that mentioned here.

I continue to believe HID will be too much for your 4' tall space unless you keep them short, scrog(?). You could use gentler, more distributed light and have the ability to grow taller plants (if that ever was desired) using the entire height of the cabinet.

But, even accepting the height limitation: you're going to have to move more air. Your stealth cabinet will risk sounding less stealthy than running some efficient LED at 20-30w/sq ft. The HID ballast will also make a sound outside the stealth cabinet.

If stealth is a priority, to me heat management would be a priority.

Click to expand...

hi bud,

Have a look at the grow area here: http://i67.tinypic.com/2nve909.jpg

i mean stealth as in, it needs to not look like a grow room but just a lockup storage area. Noise isnt too much of a problem as its in my office and no one really comes in. But i just dont want to go out and build a massive area, plus dont have the room either in here, hence why i only had an option to box a small space in the corner. no problem putting ballast outside box. if you could see the whole area of my storage/office you would see what i mean, but dont want to show too much of my surroundings, which i think you understand why but yea slight noise not an issue. I am still open to using cfl but would rather not as i want to yield as much in one go...after all it is always a risk for those 3 month so want to make the best of it

SPLFreak808 said:

No i mean the bare bulb itself is hot as fuck. The ballast is just an amplifier, it will create some type of heat but its not too bad. Anyways id keep it out of the room if possible. Just use the hps. If it gets too hot, pull in cold air.

Click to expand...

Yea mate, i will keep it out just to keep it cooler. 2 walls out of 4 are cold concrete, you think this would aid in absorbing the heat? other wall and door/roof is wood, only thin though about 5mm, plus all painted white which shouldnt hold heat like foil ay?

Have a look here: http://i67.tinypic.com/2nve909.jpg

Sali-D said:

I am still open to using cfl but would rather not as i want to yield as much in one go...after all it is always a risk for those 3 month so want to make the best of it

Click to expand...

I wouldn't let perfection be the enemy of good. CFL in reflectors work well. As mentioned in your other thread, they get a bad rap because people typically suspend them in mid air, radiating most lumens into wasted space. If you developed the mounting/reflecting/aiming, you'd be prime for LED lightbulbs which can be 40% more efficient than CFL.

It just depends on whether you want to grow taller (or anticipate wanting to). I'm sure the low-power HID would work ok, but you'll be keeping it short (probably scrog). And, I think you'll be moving more air than you anticipate (which will take away from the "it loooks like a storage lockup").

The only way to know is to try. Buy the HPS and see how it works. If you invested in a magnetic ballast you could run a Phillips All-Start CMH bulb. They run cooler while producing the same useable light. A lot of the efficient LED people are into them. (You'd have to ask about that in the LED forum, if you were interested). The worst thing that would happen is that you find the HID is too hot and you wasted some money. (I don't think you're going to be happy unless you try it and know for sure. You'll always hear that siren song in the distance... "I could have done HPS and buds would be pushing the door open." ).

az2000 said:

I wouldn't let perfection be the enemy of good. CFL in reflectors work well. As mentioned in your other thread, they get a bad rap because people typically suspend them in mid air, radiating most lumens into wasted space. If you developed the mounting/reflecting/aiming, you'd be prime for LED lightbulbs which can be 40% more efficient than CFL.

It just depends on whether you want to grow taller (or anticipate wanting to). I'm sure the low-power HID would work ok, but you'll be keeping it short (probably scrog). And, I think you'll be moving more air than you anticipate (which will take away from the "it loooks like a storage lockup").

The only way to know is to try. Buy the HPS and see how it works. If you invested in a magnetic ballast you could run a Phillips All-Start CMH bulb. They run cooler while producing the same useable light. A lot of the efficient LED people are into them. (You'd have to ask about that in the LED forum, if you were interested). The worst thing that would happen is that you find the HID is too hot and you wasted some money. (I don't think you're going to be happy unless you try it and know for sure. You'll always hear that siren song in the distance... "I could have done HPS and buds would be pushing the door open." ).

Click to expand...

Yea im with you. Led too much to shell out plus they say theres a diff technique to growing with them and not as straight forward. what i was thinking is if i use cfl, im looking at using about 16 23w bulbs which i think would be about optimum for the size of the room. yet the total actual wattage would be 368 watts, so just about 400w. so getting a 400w hps would not be much diff in electricity cost, and surely the heat will be on par if not as intense as the hps? i turned 4 cfl on together already and feel they are quite warm, so 16 of them would be alot more heat. plus you have to put them very close to the plants. Would the cfl`s be to hot to keep that close....i really dont know ay and its doing my nogging in lol...need to decide soon as my seeds will be here hopefully in a week.

Sali-D said:

i was thinking is if i use cfl, im looking at using about 16 23w bulbs which i think would be about optimum for the size of the room.

Click to expand...

This is hard to follow due to two threads. But, what you say is an incredible 92w/sq ft. If you put CFLs in reflectors, you should need 50w/sq ft. About 8 bulbs? If you used LED lightbulbs, about half that. (So, I don't know why you think it's expensive. But, I would still do 6 bulbs. Just lower watt, like 4 - 10w on the sides. 2 or 3 - 20w in the top corners.).

In the other thread you said you had access to 100 L/w CFLs. You should only need 20w/sq ft of those. (I asked for info because I've never heard of CFLs that efficient. But you didn't reply. So, not sure if that's still what you're looking at.).

A Single T5HO tube in each corner (2' long) could minimize the bulbs you have to hang. That would give 96w right there. (24w/sq ft). If you angled those in from the corner to the center of the top, that would give you decent top light. It could be adjustable (slide it deeper into the corner if the plant grows out tall/wide).

Add a 10w LED in each corner (lower) for 34w/sq ft. That would be decent. (T5HO usually runs 40w/sq ft). The LEDs would be a little more efficient, surrounding the plant with light adds efficiency.

If you didn't want to "spyder" 4 tubes into the corners like that, you could just hang a 4-tube fixture from the top. (Simpler). You might be able to move the T5HO ballast outside the cabinet. And, there are LED replacement tubes for T5HO. You could do that eventually.

There are a few different ways to do it. It's not just "CFL versus HID." (Don't be insulted, but I get the impression you're emphasizing the worst case of CFL to justify the HID. That's ok. HID may work for you. I'm just trying to point out how there are some options in between if you're worried about the heat of HID. And, I don't think CFL is as bad as you're making it out to be. 92w/sq ft for CFL is really high, especially if it's reflected decently. But, you're right. CFL is hot. They will burn leaves if they touch for very long.).

az2000 said:

This is hard to follow due to two threads. But, what you say is an incredible 92w/sq ft. If you put CFLs in reflectors, you should need 50w/sq ft. About 8 bulbs? If you used LED lightbulbs, about half that. (So, I don't know why you think it's expensive. But, I would still do 6 bulbs. Just lower watt, like 4 - 10w on the sides. 2 or 3 - 20w in the top corners.).

In the other thread you said you had access to 100 L/w CFLs. You should only need 20w/sq ft of those. (I asked for info because I've never heard of CFLs that efficient. But you didn't reply. So, not sure if that's still what you're looking at.).

Click to expand...

Hi bud, I said i had access to 100w cfl? i dont recall this, unless i made a typo? i had access to 40w cfls . Is this the comment you refer to " thinking of sticking with CFL as I have now found someone over here that sell the 45w ones for photography. Kicks out 4500 lumens within 2700k.?"

Anyway from what i read, you can grow no probs with only a few cfl, but the process would be slow and flowering would be a waste of time. Sorry but im all over the place. at first i was positive cfl would do the trick and live to my expectations, but you then listen to every ones diff comments then research what they say which leads to even more opinion, then im fked up in the head lol. i guess this is the same for most whom want to start there first grow....someone help please and tell me what i should really do to have a chance at pulling 2oz...then im super happy.

is it lumens, watts or PAR im looking at. can someone work out for the area i have, what light, how many, how many lumens/watss or what ever i should need to grow a satisfactory yield close to 2oz plus show proof if poss......im cracking up here, i just want my mind at piece

In my country all these fancy bulbs lie t5 t8 t whatever are not easy to find, in fact i called and been to all of them and the dont sell these things, well the ones that do only go to about 14w and are about 5ft tall and more. only option is shit loads of cfl which i can by in my country or hps from ebay....thanks all, sorry im jumping from one idea to another but you know what its like when you read and read and listen to opinions, it makes you so damn unable to decide whats best.

az2000 said:

A Single T5HO tube in each corner (2' long) could minimize the bulbs you have to hang. That would give 96w right there. (24w/sq ft). If you angled those in from the corner to the center of the top, that would give you decent top light. It could be adjustable (slide it deeper into the corner if the plant grows out tall/wide).

Add a 10w LED in each corner (lower) for 34w/sq ft. That would be decent. (T5HO usually runs 40w/sq ft). The LEDs would be a little more efficient, surrounding the plant with light adds efficiency.

If you didn't want to "spyder" 4 tubes into the corners like that, you could just hang a 4-tube fixture from the top. (Simpler). You might be able to move the T5HO ballast outside the cabinet. And, there are LED replacement tubes for T5HO. You could do that eventually.

There are a few different ways to do it. It's not just "CFL versus HID." (Don't be insulted, but I get the impression you're emphasizing the worst case of CFL to justify the HID. That's ok. HID may work for you. I'm just trying to point out how there are some options in between if you're worried about the heat of HID. And, I don't think CFL is as bad as you're making it out to be. 92w/sq ft for CFL is really high, especially if it's reflected decently. But, you're right. CFL is hot. They will burn leaves if they touch for very long.).

Click to expand...

cheers bud, i really understand your point, but i just can not get these t5ho bulbs in this country, especially that size, there all around 5ft and more, actually i think thats the non high output ones. leds are not easy to get and are quiet expensive. this country is like uk 20 yrs ago im not kidding you. can you put me straight....whats important watts, lumens or PAR? really appreciate your help and patience pal

Sali-D said:

Is this the comment you refer to " thinking of sticking with CFL as I have now found someone over here that sell the 45w ones for photography. Kicks out 4500 lumens within 2700k.?"

Click to expand...

Yes, that's 100 L/w. I've never heard of CFLs being that efficient. Were you able to find a link? If you really have lights that efficient, you definitely don't need 92w/sq ft. Probably 30.

Sali-D said:

is it lumens, watts or PAR im looking at. can someone work out for the area i have, what light, how many, how many lumens/watss or what ever i should need to grow a satisfactory yield close to 2oz plus show proof if poss......im cracking up here, i just want my mind at piece

Click to expand...

I thought I just did that. About 50w/sq ft of CFL in reflectors. 50w/sq ft HID. 34-40w/sq ft T5HO. 30-35/w sq ft CMH. 25-35w/sq ft LED lightbulbs.

Lumens are only useful to compare the efficiency of the same type of light. A 72 L/w CFL can be compared to a 88 L/w Cree LED lightbulb.

But, lumens is confusing because you have to have a special sphere to measure them. When you put an omnidirectional light in a reflector, it's hard to know how those lumens (on the packaging) compare to the lumens (on the packaging) of a reflected light (like a floodlight). You have to measure lux and compare the two. (Lux is the lumens falling on a specific point. Lumens is all the light emitted from a source. You can't measure that.).

Lumens are what the human eye sees. So, you can't compare that (like a white LED) to a blurple LED, or HPS due to color/spectrum differences. That's where PAR comes in. You need a $400 meter for that.

But, like I said. Just think of classes of light and the w/sq ft required.

I think you want to do the HID. That's fine. I just don't think CFL is as bad as you depicted, and there are LED lightbulbs available if you were leaning toward CFL. (And T5HO.).