Cool Mist Humidifier...do you use one?

[Guest]

I want to lower the temps in my cab so I did some reading on cool mist humidifiers. Do they work? Do you recommend one in particular?

Thanks

 

[Navigator330]

I would not think that a humidifier is a good choice to cool. The humidity level will go way up..... your RH should be lower than 60% in veg and less than 50% during flower to prevent mold etc. A humidifier would make the air in the room almost 100% thus being the equivalent to a rain forest! Try cooling your hood/lighting or adding exhaust blowers or pc fans depending on your cab size.

Moisture = BAD!

 

[Haps]

Depends on what your room needs, I do not run one now, but with more lights in my room I used to.
H

 

[Daemon]

What about if your RH is very low to begin with? Mine is around 30% usually and I can't figure out how to raise it!

 

[TGT]

I find 30% humidity is usually okay, a little higher would be better but I pull off great crops with 30% during lights on and it has not effected my yield that I know of. I think in some situations a cool mist humidifier is good, such as large op's and grows with extremely low humidity under 30%, but the problems that can be caused by it can be extreme, especially during bud. I would see how well they do with the 30%, then if you think they are effected adversly by it, then think about using a cool mist humidifier on a timer to limit its use or better yet with a humidity meter that shuts off automatically when a certain percent is attained.

TGT

 

[Navigator330]

Good point! I never thought of that issue! Running soiless mix i alway have humidity thru my pots.... plus i live in a humid house!

 

[Guest]

Well there is about 40% RH here and 45% cabin humidity. I want to up it to 50%. Viable?

 

[Guest]

I have a 400W CMH, PL Lighting hood with cooling and exhaust. 430CFM exhaust and 200CFM intake.

 

[Navigator330]

a fan on intake and exhaust? that may not be as efficient as it could with the 430 exhausting alone and having a passive intake. Take a tupperware container of water and put it on the floor of your grow and see if it raises it just enough.Good luck!

 

[bluenorth]

Hey Navigator could I ask you a question? I'm about to hook up a intake fan and can't see how it could be worse than a passive intake. I would think it would greatly assist the exhaust fan? What's your reasoning, not trying to be rude, just always looking for more knowledge. Thanks

 

[Guest]

a fan on intake and exhaust? that may not be as efficient as it could with the 430 exhausting alone and having a passive intake. Take a tupperware container of water and put it on the floor of your grow and see if it raises it just enough.Good luck!

I have a 3 gal bucket full of water but not on the floor. I put it above the cab. It might raise the RH. I don't see it on my hygrometer. I should put it on the floor though and try again.

I want to raise humidity to around 50-60% because I have read on here that it accelerates growth in veg. cycle.

Thanks

 

[Albert Hofmann]

I use a humidifier in my seedling chamber to get my RH in the 70-80% range, I've used them in flower but don't currently...MAKE SURE YOU CHANGE THE FILTER REGULARLY AND KEEP THEM CLEAN!!


blunorth - to answer your question, the intake fan will not help move more air through the exhaust fan. It will however, if improperly sized, reverse the necessary negative pressure and force air out through any possible escape point compromising your smell control.

 

[Guest]

Nice. Does it help though?

 

[Albert Hofmann]

I only use things that work

 

[Navigator330]

Blunorth:

blunorth - to answer your question, the intake fan will not help move more air through the exhaust fan. It will however, if improperly sized, reverse the necessary negative pressure and force air out through any possible escape point compromising your smell control.

I second that, also... if you have a sealed area and force air into it and blow it out it causes an air lock. Professional engineers have some math equation or something to figure this out... since im not a math person i go passive.

 

[Guest]

What is an air lock?

 

[bluenorth]

I always thought that you just need to make sure the exhaust is stronger than the intake and all is good. I'll have to experiment with passive vs. forced intake.

 

[Guest]

I am doing that. My exhaust is 435cfm and my intake is like 200cfm.

 

[TGT]

I find if the room is sealed there is usually no need for a fan powered intake. Usually a pasive intake is fine, but I guess every grow is unique so what ever works is the way to go.

TGT

 

[Guest]

I have it pretty dialed in. I had ducting issues with a 4" on a 6" fan but now that is fixed so i'm using it the fan to it's full capacity.

My temps are normal for my geographic location at this time. Average 79F