42w cfl vs 2x26watt heat generation & Question about Mini 42watters?

Hey Guys,

I noticed that when I added two more 26watters to my grow room - my temps did not change not even 1 degree - but if I take them out and put in just 1 more 42 watt GE cfl from walmart, temps go up like 2-3 degrees.

Just an observation for now. I might be replacing my 42 watt side supplemental sidelighting with 26 watters...

Kind of related, the other day I was strolling through the Target CFL section (I find myself constantly strolling through grow related isles whenever I go shopping anywhere now lol), and I saw these 42 watt Mini CFLs. I saw them and thought, "Wow, cool, so small." but didn't think much of them other than that.

Then I stumble on this:
http://www.bulborama.com/store/cart.php?m=product_detail&p=1055

and it says that they run up to 25% cooler!?!?

Anyone using them, and can confirm?

$19 each? I think not. I get 42w for 5-8 dollars each. I can think of no sound reason why one 42 would make more heat than 2 23w. Maybe it was just the way it shined on your temp meter?

I wish I was at home now, I have two very distinctly different 42 watt bulbs I could show you. One mfg has slits on the sides of the ballast for cooling, to vent heat out, and the other one does not, and holds the heat in. One gets very hot when plugged up, the other does not.

I found a pic of one with the vents, see them UNDER the bulb?




NOT all CFLs have those vents.




this is a 65 watt from Lowes, again, see the heat vents:


Feit Electric
65-Watt Twist Compact Fluorescent


Item #: 46931 Model: 017801997118


ALL 65s and larger have the heat vents.
some 42s do, some 42s do not.



I have never seen a 26 watt with heat vents, so a 26 watt CAN be much hotter than a 42 watt bulb.
Look, no vents:

Roseman said:

I wish I was at home now, I have two very distinctly different 42 watt bulbs I could show you. One mfg has slits on the sides of the ballast for cooling, to vent heat out, and the other one does not, and holds the heat in. One gets very hot when plugged up, the other does not.

I found a pic of one with the vents, see them UNDER the bulb?

NOT all CFLs have those vents.




this is a 65 watt from Lowes, again, see the heat vents:

Feit Electric
65-Watt Twist Compact Fluorescent


Item #: 46931 Model: 017801997118


ALL 65s and larger have the heat vents.
some 42s do, some 42s do not.



I have never seen a 26 watt with heat vents, so a 26 watt CAN be much hotter than a 42 watt bulb.
Look, no vents:

Click to expand...

Hm.. Awesome. Didn't think of that. I think I remember seeing some slits on the GEs I got from walmart. Not sure though, will check when I get home. Maybe they need more ventilation...

We'll see when I get home...

I also stumbled onto this popular mechanics article comparing CFLs:
http://www.popularmechanics.com/home_journal/home_improvement/4215199.html

and in the comments someone was talking about purespectrum cfl bulbs, how they are the most efficient and the future of cfls, etc.

It got me curious, so I went on a hunt for these cfls, and found some interesting info.

here is an excerpt from their FAQ
http://www.purespectrumlighting.com/technology/faq

"Q.) Can you explain how your technology works?
The base science driving PureSpectrum’s proprietary circuit design conserves energy and enables enhanced performance by more efficiently processing electric current from the power source through the ballast to the lamp. The unnecessary heat generated within the ballast components of conventional electronic ballasts leads to the production of wasted energy. Ballasts built with PureSpectrum’s technologies regulate the flow of current in direct correlation to the amount of power required to light the lamp, resulting in optimum performance and high Power Factor. Increased efficiency is created through the use of very high frequency synchronous switching, leading to a constant waveform during power conversion and virtually eliminating heat losses. As a result of this alteration in the mechanics of the lighting device, the amount of unproductive power is reduced and more light is created from less energy."

It would appear that they have found a way to make a ballast that wastes less energy as heat...cool beans

Too bad they only come in 20w currently.

yea idk how your 42w is hotter then them 2 26w i got 2x23w and they get hot to touch sometime my arm hit them when im checking my plants and its pretty hot, but my 42w i can touch with no problem. idk if its because my 42w is softwhite and my 2x23w is daylights.

Wouldn't the amount of heat generated be the same whether it was vented or not? All the heat has to go somewhere.

Illegal Smile said:

Wouldn't the amount of heat generated be the same whether it was vented or not? All the heat has to go somewhere.

Click to expand...

The total heat given off would probably be the same as far as energy consumed/btus, but with vents the heat has an escape path, and would be quick to be exhausted by the exhaust fan.

I would Imagine a bulb without vents would accumulate heat inside of the ballast, and then dissipate from the ballast, which would take longer, allowing the heat to build up and be noticeable.

But then again i am no expert...so who knows. Will do some further observation when I get home.

igrowdank said:

The total heat given off would probably be the same as far as energy consumed/btus, but with vents the heat has an escape path, and would be quick to be exhausted by the exhaust fan.

I would Imagine a bulb without vents would accumulate heat inside of the ballast, and then dissipate from the ballast, which would take longer, allowing the heat to build up and be noticeable.

But then again i am no expert...so who knows. Will do some further observation when I get home.

Click to expand...

I checked my 23w bulbs that i got from Lowes (Bright Effects brand) and they are vented, however, not very well. They have four small holes in the middle of the actual bulb and not on the socket side of the ballast. Which is pretty useless for any of our applications as heat rises and the majority of us point our bulbs to the side or down, not up. Gonna look into ways of maybe drilling more vents with no harm to the ballast..... more vents or bigger vents will definately help to dissipate the heat much quicker, especially if you have a good exhaust going out. if i find something i'll let you know. i think i have a burnt bulb and i'll open it up to see what the innards are like and if i can do anything or not.

OK, I got home and found these 4 42s, two bulbs are a NVision brand, and two are no-names.

The no names are vented and show BURN or discoloration on the ballasts where the HEAT escaped. (the two in the center of the first pic)
The two NVision bulbs are not vented, no holes on the top or side of the ballast.

That is all I can tell you or show you. I am just saying some are vented, some are not.

Thanks for the info Roseman

Actually those two center bulbs are the GEs - same as the ones I have from walmart. That tiny little spirally looking vent in the center of the top of the ballast is one of the only vents - there are like 3 slits around the bottom of the ballast where the screw in part of the bulb is. I had a broken one, so I popped the ballast open, and yea, it is definately gonna be hard for the ballast to evacuate all that heat through those little spaces. I think I'm gonna drill a bunch of holes in the ballast body and see if that helps out - I think it really will.

I will take pics of the ballast and vents as it is stock as well, and then post pics of what I modded.

Also, I have two reflectors I built , following the DIY CFL reflector video on youtube - i think I'm gonna drill a couple of holes in it right behind the ballast and bulb also, because I think the heat is having a hard time getting out of the upside down U created by this damn duct reflector lol.

Will let you know what, if anything, it does to the room.

If a bulb is producing x amount of heat then x amount of heat will be transferred to the air around it no matter what you do. Vents might keep the bulb from overheating but they won't make any difference in your airspace. The only way you lower the temp of your airspace is by bringing in air that is cooler.

Illegal Smile said:

If a bulb is producing x amount of heat then x amount of heat will be transferred to the air around it no matter what you do. Vents might keep the bulb from overheating but they won't make any difference in your airspace. The only way you lower the temp of your airspace is by bringing in air that is cooler.

Click to expand...

I know your right Illegal - but I think if I get some ventilation holes in the ballast, the hot air will actually be able to escape the ballast assembly - as it is now, you can see that the plastic is turning orange because the trapped heat isbaking it (only at the the small ventilation hole that Roseman showed us, which I would think is happening becuase the ventilation of the heat from within the ballast is barely escaping...we'll see how it likes having a lot of intake and exhast to work with)- with the negative pressure in the room, with the cool air coming from the living room (kept at 70 with AC), if I could at least get that heat to move faster and be exhausted by my blower - I think I might find a few extra degrees.

As it stands, in a closet that is 2.5' wide, 2' deep, and 8' tall (thats only 40cu.ft) with only 7x42 watt 2700k's, and 2 26 watt 6500k's, the room maintains an 88 degree temperature, even though I have 3x4" passive exhaust with no air restriction on intake, a stanley blower sucking through a DIY carbon scrubber (6"OD, 4"ID x 24" long) and blowing out a 4" exhaust, at the very least at 200 cfm (my exhaust vent has little louvers - they are pushing straight out, so it is pushing good)

We'll see, your probably right that it will not change anything, but at this point I am willing to try anything just to learn from this experience more.