Live Stoner Chat RH high during dark period?

[Happy Horticulturist]

Clearly i can't be running an RH of 85 percent during dark period right? this will cause mold, even thou i have a 16 inch osilating fan blowing on my plants. I have a window AC unit which is running in the room, should i try turning it off during the dark period?

AC usually helps to remove humidity from the air but it needs the air to be warm to do that.

The cooler the air becomes the higher the humidity will rise. The reason being is this...

Imagine you've got a sponge (the sponge represents warm air) and it's half full of water, your relative humidity is 50%. Now you take your sponge and you squeeze it to 3/4 it size (representing the air getting cooler because cool air contracts) now your relative humidity is 75%, even though the same amount of water is there. Now squeeze the sponge tighter and tighter and water will start falling out of the sponge/air and onto what ever is around.

This is what happens to your humidity levels even though the only thing that's really changing is the air temperature from day to night.

The way to get around this is either to a) increase your air temps at night to be the same as day b) get a humidifier and have it running (especially at night, or at least in the hour or two before lights off, all the way throught the night and for the first hour or two during lights on).

Lots of dehumidifiers create warmth as well as dehumidify so it (a dehumidifier) will attack the problem on both fronts.

 

[DubV]

I agree with HH. Get a dehumidifier and raise those temps or turn the AC off completely. 74F is a few degrees to low for ideal growth. I like to run between 78-86 with Led's. Photosynthesis kicks in high gear between 78-84f. Humidity I like to run around 40-45% in flower with 50% being the highest. Do you run it that low for res temps?

 

[namvet25]

Air conditoners take humidity out of the air.Is it in the grow room or out.

 

[lykaboss]

Yea i need to run my room temps below 75f in order to keep my res temps in check

 

[lykaboss]

Thanks all for the replys i have a better understanding, but i still need a bit of help... See i run (currently) A closed loop system on my hoods. See Pictures below

ALso i recycle the air in the room by using a 8 x 24 inch phresh filter with a phresh Hyper Fan, its only running at about 50 percent right now

My current readings with lights on...

I have removed the 32 gallon trash can filled with water out of the grow room and i have reset the min and max readings to see what happens in tomorrows dark cycle. To see if removing the trash can did any good. Its getting to about 89 RH in dark cycle, and there in lies the problem. If i can get to down to around 65 to 70 RH i think i would be good.

Trying to avoid buying a dehumidifier i would assume the extra power draw of one would be significant. Course i have no experience with stand alone dehhumidifiers

I have an 8000btu window ac unit in the grow room

 

[Happy Horticulturist]

I have removed the 32 gallon trash can filled with water out of the grow room and i have reset the min and max readings to see what happens in tomorrows dark cycle. To see if removing the trash can did any good. Its getting to about 89 RH in dark cycle, and there in lies the problem. If i can get to down to around 65 to 70 RH i think i would be good.

Trying to avoid buying a dehumidifier i would assume the extra power draw of one would be significant. Course i have no experience with stand alone dehhumidifiers

I have an 8000btu window ac unit in the grow room

So you got 89 RH in dark cycle.

What were the air temps?

What that with the window aircon unit on or off?

I take it you have no extraction? So your only way of removing moisture from the environment is the aircon unit? Does the aircon unit have a drain line, if so where does it go?

I'm sure I can help you solve this problem but I need more info bro

 

[lykaboss]

room temps dropped to 68f in dark cycle with 89 RH.

Window unit is always on, but not sure if its really running in the dark cycle.

Window AC unit does not have a drain line.

I was always thinking that maybe i could disconnect one side of the closed loop system on the hood and have it to where its pulling air from the top out of the room?

I am curious to see what the readings are tonight since i have removed the trash can

 

[Happy Horticulturist]

The plants are transpiring which means they're basically sweating and it's evaporating into the air. Whatever water they are drinking a majority of it goes into the air.

How are you removing that water from the room then?

It sounds like you've got a closed loop system but nothing is draining moisture from the air...

Also if that's the case, how then is fresh CO2 laden air entering the room? Plants will completely use up all the available CO2 in a room in a matter of hours.

If you are able to extract stale air and intake fresh air I would do that. Otherwise in a closed loop system you need some sort of effective dehumidifying process and compressed CO2 bottles and a controlled injection system.

 

[lykaboss]

I think this weekend what i will do is, take that 8 inch hyper fan and phresh filer and mount it up on the ceiling by the hoods install an 8 to 6 inch reducer and hook it into the hoods. This way it can pull air from the room threw the carbon scrubber - threw the hoods - then out... then use the 6 inch on the other existing hole as an intake.

Hopefully it will correct the RH issue.