Enclosed Hood w/double ended bulb

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Big Daddy420

Member
I had purchased a double ended 100 watt light and eventually found a enclosed hood with glass to go with it. I heard comments that the air passing over the bulb will lessen the output of moles to a degree were it is inefficient and counter productive. Can anybody clear this up for me, I thought by enclosing the heat esp in 8 foot height and evacuating it the tent would remain manageable so far as the heating problem caused by the lamp.

Also, can I run a led and double ended in same tent (8 by 4)? I don't have the bucks to buy new led lights nor can't find a buyer for the equipment already purchased.

Big Daddy420
 
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Big Daddy420

Member
a 1000/1200 watt DE bulb pulling about 9.7 amps. Just asking the hood is direct air flow enclosed glass which I can take off but wondering about the air flow over the lamp and not deflected above it like some I have seen. Will this lessen my micro moles production to a degree which is counter productive?
 
Herb & Suds

Herb & Suds

Well-Known Member
Big Daddy420 said:
a 1000/1200 watt DE bulb pulling about 9.7 amps. Just asking the hood is direct air flow enclosed glass which I can take off but wondering about the air flow over the lamp and not deflected above it like some I have seen. Will this lessen my micro moles production to a degree which is counter productive?
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I have no idea what micro moles are
I assume you mean output?
 
B

Big Daddy420

Member
J232 said:
You don’t want air flowing over a DE bulb, cooling by airflow over the bulb will affect the outputs. They make air cooled hoods for DE bulbs or run it sealed or open.
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so basically I bought a worthless hood because the air needs to be above the electric housing. Thanks any recondemations for hood?
 
Killaki

Killaki

Well-Known Member
Ok let me clear some things up. I've been seeing this from time to time and thought I'd explain some things about light. So 1- a fan can't blow the light around, some photons maybe be reflected or refracted by particles in the air being blown around by the fan but this is extremely minimal.
2-florecent lights work best when they're warmed up and if you're blowing a fan directly on them it may cause the light to run suboptimal. That being said I personally feel if the temp is dropping that much to mess with the light your grow space temps are probably too low. Of course you can always test it and see.
**I see I misread and you're running a DE bulb not cfl. But this is a similar situation. Is it a fan blowing on it or some other air flow? How much we talking here?
 
Herb & Suds

Herb & Suds

Well-Known Member
Ok now we are communicating
That hood is useless for a DE with attached ballast
And yes you will have heat issues if you don't vent properly
That is one reason I don't switch to de
I have hoods like yours in one room and wide open ballast in another but both need A/C

Now on to figuring out what "micro moles " are? :hug:
 
B

Big Daddy420

Member
Killaki said:
Ok let me clear some things up. I've been seeing this from time to time and thought I'd explain some things about light. So 1- a fan can't blow the light around, some photons maybe be reflected or refracted by particles in the air being blown around by the fan but this is extremely minimal.
2-florecent lights work best when they're warmed up and if you're blowing a fan directly on them it may cause the light to run suboptimal. That being said I personally feel if the temp is dropping that much to mess with the light your grow space temps are probably too low. Of course you can always test it and see.
**I see I misread and you're running a DE bulb not cfl. But this is a similar situation. Is it a fan blowing on it or some other air flow? How much we talking here?
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I was going to set the inline fan on low which is a 8 inch and been using humidity/temp sensors. using 55 rh and 77 degrees as benchmark
 
Killaki

Killaki

Well-Known Member
Seriously
Herb & Suds said:
Ok now we are communicating
That hood is useless for a DE with attached ballast
And yes you will have heat issues if you don't vent properly
That is one reason I don't switch to de
I have hoods like yours in one room and wide open ballast in another but both need A/C

Now on to figuring out what "micro moles " are? :hug:
Click to expand...
I've seen moles used as a unit of measurement for daily light output of a grow space. I've delved pretty deep into the world of lighting mostly because I was seeing some shit that scientifically didn't make sense to me. Basically the op wants to know if having a fan by the light will drop the daily light output. Short answer, no.
 
MidnightSun72

MidnightSun72

Well-Known Member
Killaki said:
Ok let me clear some things up. I've been seeing this from time to time and thought I'd explain some things about light. So 1- a fan can't blow the light around, some photons maybe be reflected or refracted by particles in the air being blown around by the fan but this is extremely minimal.
2-florecent lights work best when they're warmed up and if you're blowing a fan directly on them it may cause the light to run suboptimal. That being said I personally feel if the temp is dropping that much to mess with the light your grow space temps are probably too low. Of course you can always test it and see.
**I see I misread and you're running a DE bulb not cfl. But this is a similar situation. Is it a fan blowing on it or some other air flow? How much we talking here?
Click to expand...
DE bulbs lose efficiency when they are cooled directly over the glass as they use nitrogen gas behind the jacket where a normal HPS bulbs has a vacuum instead. The nitrogen lets the lamp burn hotter and more efficiently. But it also has the drawback of being thermally conductive. And thus when you run air over the glass you can decrease the bulbs internal operating temperatures and shift its spectrum and efficiency negatively.
 
Killaki

Killaki

Well-Known Member
MidnightSun72 said:
DE bulbs lose efficiency when they are cooled directly over the glass as they use nitrogen gas behind the jacket where a normal HPS bulbs has a vacuum instead. The nitrogen lets the lamp burn hotter and more efficiently. But it also has the drawback of being thermally conductive. And thus when you run air over the glass you can decrease the bulbs internal operating temperatures and shift its spectrum and efficiency negatively.
Click to expand...
Correct. That's in fact what my post you quoted was getting at. But that's why I'm wondering exactly what the setup is.
 
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