Question on removing glass from air cooled hoods

motoracer110 · Mar 19, 2017

i have grown many many years with are cooled hoods and am wanting to make a Chang but would like some thoughts.

My grow is in a bedroom with 2 1000w air cooled hoods that vent outside. I keep the room at a negative pressure so no bad air can escape into the house and am not able to add a separate ac system. The room stays about 79-81 lights on and 67 lights out. I'm wanting to take off the glass on both hoods and have a each hood have a dedicated intake that pulls air up around the bulb and exhausts out of the room. Do you think this will keep temps low enough and do you think it's worth it to get the extra output from the lights?

OG electric · Mar 20, 2017

Your temps will increase dramatically without the glass on
I've heard 10-15% more lumens with no glass

Owly · Mar 20, 2017

It's hard to say exactly how things will change, but it's easy to test. Temp will definitely go up, but maybe manageable.

xmatox · Mar 20, 2017

Owly said:
It's hard to say exactly how things will change, but it's easy to test. Temp will definitely go up, but maybe manageable.

Temps will go up, but so should your yield.

chea.pet · Mar 21, 2017

Temps will go up about ten degrees. I run open hoods have for five cycles now. You can increase fans, and lower canopy to compensate. Also increased watering will insure plants can take increased heat. Your yield will increase..

chemphlegm · Mar 21, 2017

my temps didnt change. I have an ac unit. my costs went down. I used to vent through the hoods, nd use an ac unit. then removed the glass and sealed the room with c02 no outdoor exchange. never looked back sorta..... i do now regret paying for fancy hoods, knowing the wings or bare bulbe are fantastic

chea.pet · Mar 21, 2017

Bat wings and base bulbs are the best, and I split rooms each has a mini split ac.ac is important each room has aco2 burner. Best yields

Owly · Mar 21, 2017

chea.pet said:
Bat wings and base bulbs are the best, and I split rooms each has a mini split ac.ac is important each room has a co2 burner. Best yields

Bat wings are the best? I take it you haven't tried vertical bare bulb yet... but that probably gives the worst gram per lobar hour numbers.

chea.pet · Mar 22, 2017

Owly said:
Bat wings are the best? I take it you haven't tried vertical bare bulb yet... but that probably gives the worst gram per lobar hour numbers.

I have a space in mind to run vortical j just have not had the time to set up yet. With three grows running is hard to find the time,lol

Roger A. Shrubber · Mar 22, 2017

i had a large hood with a 400 watt hps in a tent it barely fit in. i had plenty of vertical room, but it had just a couple of inches between the hood and the tent all the way around. i tried it with the glass out and temps went up about ten points, from around 78 to about 87-88 F., and after a month i didn't really notice a lot of difference in growth. i put the glass back in and turned the fan back down slightly, it got quieter, cooler, and growth seemed the same to me

chemphlegm · Mar 22, 2017

Roger A. Shrubber said:
i had a large hood with a 400 watt hps in a tent it barely fit in. i had plenty of vertical room, but it had just a couple of inches between the hood and the tent all the way around. i tried it with the glass out and temps went up about ten points, from around 78 to about 87-88 F., and after a month i didn't really notice a lot of difference in growth. i put the glass back in and turned the fan back down slightly, it got quieter, cooler, and growth seemed the same to me

add c02 to those raised temps and you would

Owly · Mar 22, 2017

Roger A. Shrubber said:
i had a large hood with a 400 watt hps in a tent it barely fit in. i had plenty of vertical room, but it had just a couple of inches between the hood and the tent all the way around. i tried it with the glass out and temps went up about ten points, from around 78 to about 87-88 F., and after a month i didn't really notice a lot of difference in growth. i put the glass back in and turned the fan back down slightly, it got quieter, cooler, and growth seemed the same to me

Lot of factors playing into that. The glass free advantage is pretty slim, like 5% yield boost or something (unless you don't clean your glass). But changing the temp changes lots of things.
At 88F you should be shooting for 75-85% relative humidity, where as at 78 you want more like 65-80%.

Roger A. Shrubber · Mar 22, 2017

i grow in a tent, its always seemed like it would be a waste of time to add co2 to an environment where the air is exchanged that fast

chemphlegm · Mar 22, 2017

Roger A. Shrubber said:
i grow in a tent, its always seemed like it would be a waste of time to add co2 to an environment where the air is exchanged that fast

as it would be to raise temps in there to 88 expecting more growth?

Roger A. Shrubber · Mar 22, 2017

it was an experiment, i wasn't sure what kind of an effect it would have, i didn't really expect anything, i was seeing what would happen

Question on removing glass from air cooled hoods

motoracer110

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OG electric

New Member

Owly

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xmatox

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chea.pet

Active Member

chemphlegm

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chea.pet

Active Member

Owly

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chea.pet

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Roger A. Shrubber

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chemphlegm

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Owly

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Roger A. Shrubber

Well-Known Member

chemphlegm

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Roger A. Shrubber

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