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Exhaust 24/7?

I usually turn my exhaust on about a half hour after my lights turn on...once the room warms to about 75-78 degrees F... to maintain temps.....but am i looking at it all wrong? I feel like i should be using exhaust for air circulation/ quality....i feel like it should run when the lights are off as well......is this correct?

I have to do some tests to see what my temps settle at with the exhaust running when the lights are off. Currently with the lights and exhaust off, the room settles right at the limit of between 60-65 degrees F..with a scary day or two where it dropped into the high 50's.

I though about at least turning it on for 15 mins or so every hour just to keep the air fresh.


Other than the exhaust I have oscillating and stationary fans, and a dehumidifier that run 24/7.

SO.... keep it the way it is?...or exhaust all day, or at least sometimes when the lights are off?

thanks for any replies!
 

SmilinBob

Member
Why not use a voltage regulator and just turn it to low while the lights are off? Someone referred me to a regulator called a Dial a Temp a long time ago. It's cheap and works. Turn it down at lights off, and turn it up at lights on.

You'll probably need a different one though, depending on how many amps your fan pulls.
 
Why not use a voltage regulator and just turn it to low while the lights are off?

Well I am just now realizing it's prolly a good idea to use it when they are off....

But I'd have to switch the fan that i use for exhaust with the one I am going to put on my filter, because I am exhausting with a can max fan, which i was told, cannot be used with a regulator....
 

qbert

Member
I think it would be good to circulate the air occasionally during lights off time. If you have a half decent digital timer you could program it to come on for like 10 minutes every hour during lights off and all through lights on. I personally leave mine run 24/7 but I don't get anywhere near as cool during lights off.
 

Clackamas Coot

Active member
Veteran
I grow in a 4' x 4' tent (the one from Germany - whatever) and I have a 275 cfm exhaust and a much smaller fan for intake.

Both run 24/7 - is that bad?

Just curious.

CC
 

PuReKnOwLeDgE

Licensed Grower
ICMag Donor
Veteran
Run them 24/7, in flower humidity will kick your ass at night time. Also, if my scrubber stops for a few hours, the smell starts to pour out. IMO, there is no question, fans run 24/7 and thats the end of that :)
 

goldenahms

Member
Not bad, fresh air is good. I run my exhaust and fan 24. The fan regulator someone suggested is a great idea if low temps are an issue. Double check with your manufacturer or reseller and see if it's possible to attach a fan controller.

If high humidity and mold are an issue in your location, you need fresh air exchange. Even if it wasn't, I'd still recommend some air flow at lights out. Good luck:wave:
 

FreezerBoy

Was blind but now IC Puckbunny in Training
Veteran
Pure nailed it. Even without the benefit to the plants, grower safety suggests 24/7 as the only option.
 

Yes4Prop215

Active member
Veteran
just started thread with same question...people say to run 24/7 unless you can attach to a climate controller which will turn it on once humidity reaches 50....
 

VerdantGreen

Genetics Facilitator
Boutique Breeder
Mentor
ICMag Donor
Veteran
as already said, you need it running 24/7 just for the smell issue, never mind the fact that the plants also need fresh air. my temps go down to mid 50's and lower with the lights off and the plants are just fine - even helps them colour up a bit.

there is no discussion to have. 24/7 exhaust & carbon filter. temp problems can be sorted by heating the room or the intake air.

some kind of fan speed controller is handy to get the flowq down when temps get lower.

VG
 
I exhaust 24/7, and there's no way I'd ever do other. I also circulate 24/7, with a 10" oscillating fan. The plant needs CO2, it will consume the CO2 on the leaf margins. It simultaneously exhales other gasses and moisture. It will rapidly consume all the CO2 at the leaf margin, and replace that with its own waste; the other gasses and the moisture.

You would not have a happy life if you were forced to bathe in your own excrement, as it built up around you for lack of disposal.

That which is at rest tends to stay at rest, unless acted upon by an outside force.

http://www.physicsclassroom.com/class/newtlaws/u2l1a.cfm

Newton's first law.

The gasses the plant exhales will stay at rest...right there at the leaf, without an outside force to push it away or draw it away. The plant will suffocate in its own wastes to a greater or lesser degree, unless some outside force pushes the exhalate away.

You must both circulate...to push the wastes away from the leaf margin, and ventilate...to bring fresh CO2 into the room and rid the room of waste, 24/7 in an indoor grow.
 

ChaosCatalunya

5.2 club is now 8.1 club...
Veteran
24/7 for all of the good reasons above, plus also it is more reliable and quieter, IMO. Fans starting up, turning off and changing speed are all more likely to be noticed by neighbours and passers by, or go wrong, than a fan running 24/7.

An old friend ran a centrifugal fan 24/7/365 in his mums loft for 16 years continuously with no problems.
 
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