Temp and humidity way too high

I have 4 600w hps lights with two 10" fans(one for intake, one for outtake) and my temp is always between 30*c(86*f) and 35*c(95*f)... And the humidity is always over 70%... Im in the last week of flower and have got bud rot on some plants


how do i lower the temp and humidity to avoid bud rot next time?

Air conditioner to lower temps and dehumidifier to lower humidity. Air cooled hoods will help with the temps but with 4 600s and temps that high already id say a a/c might be needed. Id also loose the intake fan and just use a passive intake. Are you in a tent or a open room?

BIGGER FANS! Because fans cool air!! No, really Air conditioner to lower temps.

im growing in an attic but ive sealed it up with white black white reflective paper so its like a tent...

so wud air cooled hoods not be enuff? and why stop using the intake?

i didnt want to use an ac or dehumidifier coz i didnt wanna add to the electricity(im paranoid about someone clocking on lol)

Nobody cares about your power bill. You're running 4 600w's I'm sure a 4 or 500w a/c won't be that big of a deal. If your attic is 85 degrees adding air cooled hoods won't bring it down below 85 degrees. What's the ambient temperature of the attic? That's the coolest your grow area will ever be.

so keep growing moldy buds in your attic if you dont want to take the advice you asked for. before i ever started growing and was designing my room i knew i would need an ac and dehumidifier. they are basics for indoor growing.

superstoner1 said:

so keep growing moldy buds in your attic if you dont want to take the advice you asked for. before i ever started growing and was designing my room i knew i would need an ac and dehumidifier. they are basics for indoor growing.

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People seem to be under the impression if you run an air cooled hood and a big ass inline fan your grow room temp will magically be lower than the ambient temperature of the room it's in.

sorry... i didnt mean to come across as ungrateful for ur advice..

so wud u say forget the air cooled hood? or get this as well as the ac and dehumidifier?

Dankfarmer2012 said:

sorry... i didnt mean to come across as ungrateful for ur advice..

so wud u say forget the air cooled hood? or get this as well as the ac and dehumidifier?

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air cooled hood + a/c and a dehumidifier since you're growing in an attic, humidity is usually really high up there.

Four 600 watt hps lights + Two 10" fans=moldy bud!

You didnt forsee a problem? Priceless!

Dankfarmer2012 said:

I have 4 600w hps lights with two 10" fans(one for intake, one for outtake) and my temp is always between 30*c(86*f) and 35*c(95*f)... And the humidity is always over 70%... Im in the last week of flower and have got bud rot on some plants


how do i lower the temp and humidity to avoid bud rot next time?

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Add more fans or move a helluva lot more air.

http://botanical.com/hydro/air/calculating_fan_requirements.html

attic= warm/hot and moist air. if you move more warm/hot and moist air you will still have warm/hot moist air that gets even more so because the grow is adding to it. you need to cool the air and remove the moisture.

Portable AC unit will both dehumidify (as the machine uses frion to remove heat from the air it simultaneously removes molecules of h20, moisture and humidity, from the room). You will just need to duct the exhaust of your portable ac unit out of your room because the exhaust will be filled with hot, humid air. Portable ac unit, do it now, if possible

PS: in the future make sure you do your best to correct fundamental flaws in the grow room such as improper temperatures or levels of humidity as soon as possible. This will assure that you obtain the best bang (in yield) for your buck (spent in electricity, lighting, soil, nutrients, circulation, genetics, etc.).

Dankfarmer2012 said:

sorry... i didnt mean to come across as ungrateful for ur advice..

so wud u say forget the air cooled hood? or get this as well as the ac and dehumidifier?

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The most effective approach to lowering humidity and temp in your room would be to install a powerful (300-700 cfm) inline fan to pull air through your hoods. Use insulated ducting on the inline air cooled system to further reduce radiative heat that could warm up your room. exhaust this air outside if possible. Then install the portable ac unit (you will need 2800-3000 btus per 1000w of hid lighting, so for 2400w i would go with a 9k btu portable ac unit just to be safe. With these two ammendments to the room your temps should be down between 70-85*F and your humidity should be down between 20-50% (20-30% is probably a more accurate estimate, those portable ac units remove an incredible amount of moisture from the air, so much so that when I bought a portable ac unit I hated it cus it would remove all the humidity from my room and leave my plants to struggle in the dry desert like moisture deprived room.

i really would never recommend a portable ac to my worst enemy. if its all you have or can use, ok, but they are so very inefficient and not sealed at all.

superstoner1 said:

i really would never recommend a portable ac to my worst enemy. if its all you have or can use, ok, but they are so very inefficient and not sealed at all.

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+1 to this. Portable a/c's are insanely inefficient.

mr2shim said:

+1 to this. Portable a/c's are insanely inefficient.

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I can definitely believe that. Could you elaborate? Why is it so inefficient?

mnmobbin said:

Air conditioner to lower temps and dehumidifier to lower humidity. Air cooled hoods will help with the temps but with 4 600s and temps that high already id say a a/c might be needed. Id also loose the intake fan and just use a passive intake. Are you in a tent or a open room?

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The A/C unit will also lower the RH, just a byproduct of the cooling process

Dankfarmer2012 said:

im growing in an attic but ive sealed it up with white black white reflective paper so its like a tent...

so wud air cooled hoods not be enuff? and why stop using the intake?

i didnt want to use an ac or dehumidifier coz i didnt wanna add to the electricity(im paranoid about someone clocking on lol)

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If you're in the attic, consider one or two attic vent fans, (you know the ball shaped ones that you see spinning on roofs?)
Also, if you use a portable A/C unit there, you would be fighting yourself with the condensation and the exhaust from it.
Can you run a duct and register tapped in from your house A/C?
It won't be as effective as it could be, without a return up there, but it should still help quite a bit.

imchucky666 said:

If you're in the attic, consider one or two attic vent fans, (you know the ball shaped ones that you see spinning on roofs?)
Also, if you use a portable A/C unit there, you would be fighting yourself with the condensation and the exhaust from it.
Can you run a duct and register tapped in from your house A/C?
It won't be as effective as it could be, without a return up there, but it should still help quite a bit.

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Good call! Vent the shit out of your attic! Get up there, cut a few holes with skillsaw, add vents! I would add atleast 4...may correct your problem combined with some larger fans? Good luck!