Humidity

[KnowTheGrow]

So, I'm in the second week of flower and struggling to keep humidity below 60. It's been rainy af where I'm at and the humidity is high. I've got an a/c and a dehumidifier in the room to no avail...anyone have any suggestions?

[Chefbjy]

Wow are you running them both at the same time? Sounds like you need some better air flow. Are you exhausting it all into the room or outside?

[KnowTheGrow]

Yea, I'm exhausting into.the room and 2 8 inch oscillating fans

[UrbZ]

Running them both at the same time is probably why you are having issues. The ac puts off cold air, the dehumidifier puts off warm exhaust. Together the cold and warm air mix creating humidity. Try just running the ac on full blast with no dehumidifier.

[DW2]

Howdy KnowTheGrow, Is Your A/C unit a window unit, or the main central unit for the house? If it is a window unit (a refrigerated unit, not a swamp cooler) try setting it to recirculate instead of exhaust so as to not bring in humid air from the outside. Basically a dehumidifier is an A/C unit, chilling the humid air to condensate the moisture out of the air. Also, make sure that the drain line on the A/C unit is not clogged up and is draining properly (to the outside for the window unit). The central A/C unit should also have a condensate pan and drain line as well, check that as well to make sure that it is draining properly.
Good luck with Your grow.

[UrbZ]

Sorry yes a dehumidifier works does work similar as an AC unit but it puts out heat instead of cool air my friend.

[DW2]

UrbZ, I was not doubting the fact that a dehumidifier would vent or exhaust warmer or hot air, I was trying to give some possible solutions for reducing the humidity in the grow room. Where I live (a semi arid area) the problem here is ,always, low humidity. usually in the teens to low twenties. My grow room this morning was only at 32% RH, and today it is cloudy and a chance of rain.

[UrbZ]

Its all good I just didn't want him to think running the dehumidifier would cool his room at the same time. As he already found out running just the dehumidifier his temps jumped.

[KnowTheGrow]

Thanks for all the input. It is a window unit and I have been running them at the same time. I'll try turning the dehumidifier. off and see if that helps.

[alltatup]

KTG, I had to buy a big dehumidifier for my grow room--a 50 pint one because the little ones don't do shit. I place my dehumidifier in the doorway of my grow room so the hot air blows out into the hallway. See if that helps your temps.

[KnowTheGrow]

I ended up turning the a/c off and only running the dehumidifier. That seemed to be the best solution, only prob is the heat gets into the 80's. Think I'll get a 12in fan to replace one of the 8in and see if that helps. I already have a booster fan as a passive intake.

[Weed Pharma]

You are heading in the right direction- as the relative humidity decreases when the temperature increases;
example found shows a rh of 48% @ 60f= a rh of 100% @48f, but a rh of 24% at 80f.

http://ocw.usu.edu/Forest__Range__and_Wildlife_Sciences/Wildland_Fire_Management_and_Planning/Unit_4__Temperature-Moisture_Relationship_4.html

[DrPhoton]

Weed pharma is right, heat is your friend with high humidity problems. Temperatures up to 86°F is fine, only when temperatures exceed 86°F does the photosynthetic efficiency start to decline. The only way to further reduce humidity without introducing more heat is by using a larger or more efficient use of a dehumidifier. If your dehumidifying a room, then a larger unit is the only choice. However you can place a dehumidifier inside your grow tent but you must deactivate your airflow system and have a very small intake system to bring in fresh air. This allows the unit to bring humidity down without the dry air being taken out by the exhuast system.

I had to deal with all sorts of environment problems in my greenhouse which DW2 and others were very good at helping me with.

[UrbZ]

Are you in a tent?

[oldjarhead100]

no I'm in a house

[DW2]

oldjarhead100, 30,000 comedians out of work and You're making jokes for free!! LOL!
(actually, I'm just jealous that You BEAT ME TO IT!!!)

[oldjarhead100]

I just couldn't resist lol

[KnowTheGrow]

Lol, yea I'm in a tent...4x4x6. My little dehum. has the room at 50% just no a/c. I'm gonna see how hot the tent gets when the light flips on. Maybe it'll stay in the low 80's without the window unit running.

[UrbZ]

Do you have the option to leave your tent open with lights on?

[KnowTheGrow]

That's what I'm doing right now. While I'm home it's ok but...I don't think the humidity will be an issue much soon. Summer's coming and it's normally pretty dry here, hopefully!

[UrbZ]

I fought the same issues and likely followed the same steps to remedy them. 75% RH mid flower. I tried all the tips and tricks none worked. I ended up buying a 75 pint dehumidifier. I use that to drop RH. I had to keep the tents open with the window cracked to manage the insuing high temps.

[KnowTheGrow]

I'll post some pics here in about an hour. They're looking pretty purdy

[KnowTheGrow]

[UrbZ]

Very nice!

[DW2]

Very nice, healthy looking plants!

[alltatup]

Mighty purdy indeed!!

[KnowTheGrow]

Thank you thank you...golf clap. Lol, nah...I know it's not over yet. Plenty of time for me to mess it up lol. I didn't quite fill up the canopy but that should be an easy fix next go around.

[oldjarhead100]

Know the grow I would say your doing great.

I have a friend who has his dehumidifier outside of his room and he piped the air in and out so he doesn't have to deal with the heat