Intake air too cold??

[Critical Kid]

I am worried that my intake air may be too cold, I stuck a digital thermometer inside the intake for a minute and it showed the air was 7 degrees celcius. Is this too cold to be blowing on the plants? The temp. is dropping to around 16C when lights are off.

 

[jagle]

is about 16c which is 60f the lowest your air temp should go at night?

 

[poohpickle]

also don't have the air blow directly on the plants if possible diffuse the intake

 

[ookiimata]

16C is fine. Just don't let it go below 13C. As to the intake air stressing the plants...I dunno, in my area we worry about cooling the room down, not heating it up, so I have no experience with very cold air blowing on the plants. I imagine if you keep the flow from blowing directly on the plants as poohpickle suggested, and the temp reading at the plants' level is consistently warm enough, you won't kill them. You could also reverse the normal setup of new air in the bottom, hot air out the top and draw the intake air across your lights then suck it out at floor level to heat it before it's introduced to the plants.

The best way to figure out if it's too cold is to see how the plants do. If you're using fem seeds and end up getting some hermies, it may be due to stress caused by the cold air blowing on them. But if they seem happy, you're probably okay. The leaves curl up when they're too hot. I'm not sure what they do when it's too cold.

 

[Critical Kid]

Yea I use a heater to keep the temp around 16C at night, and I shut off the intake and out off to keep some heat in. The funny thing is the cold air is blowing right on the tops of the plants, but they are doing amazing! No leaf distortion or curling, everything is looking very stong, healthy & happy. I guess if it aint broke dont fix it right!?

 

[f1ydave]

They probably love it. There is a reason why wine grapes are grown where it gets cold at night and warm in the day.

 

[Critical Kid]

They probably love it. There is a reason why wine grapes are grown where it gets cold at night and warm in the day.

That's a very good point, I have always seemed to get more potent results when temps are lower at night.

At night when the temps drop the humidity is soaring up to %85. Is this ok? I am worried it may cause bud rot as I enter week 5 & 6 of flowering. I had 3 or 4 kolas that started to rot last cycle.

 

[jagle]

ya cold air should only make the plant produce more resin to keep itself alive? there fore producing more thc in flowering, am i right? im not sure but thats what i gathered, and id say the humidity is a bit high for the nighttime

 

[paulycali]

You can hyper dehydrate your plants with any airflow pointed directly at it. The air must oscillate. Turn off your intake at night or turn off your intake all together and let the negative pressure from the exhaust fan pull the air naturally through the intake. That should be sufficient if your worried about it getting to cold. Good luck

 

[f1ydave]

you don't want humidity to go over 55% during flower, get a DEHUMIDIFIER fast!!

 

[dentonland]

i have 3 3x6 tables lined up. the table closest to the a\c are hurting compared to the ones by the exhast canister at the opposite end. my ac is the in room type , ducted outside. tooo cold may slow ya down as it did here.. reaching 64 at nite

 

[antimatter]

I do freezing air intakes with Filter material on em (just gotta cut more holes to make up for cfm loss) and heat during the night cycle with heater/dehumidifier, my night cycle is in the 70's for me right now and its cold as hell outside and my growroom isn't very well insulated.

 

[Critical Kid]

I put a dehumidifier in the room and turn it on at night...but the humididty is still climbing to high 60's-low 70's...what else can I do to drop it?

 

[motherlode]

I put a dehumidifier in the room and turn it on at night...but the humididty is still climbing to high 60's-low 70's...what else can I do to drop it?

whats the diference in your lights on temp and lights off?

 

[xX Kid Twist Xx]

turn it on all the time after a week or so it should be able to catch up and u could turn it on and off or lower it

 

[Critical Kid]

whats the diference in your lights on temp and lights off?

Light's on temp 20-24C
Light's off temp 17-20C with heater, otherwise it would drop to 13C.

 

[motherlode]

humidity spikes when the temps drop - I try and keep the lights off temp and lights on within 10 degrees (f)

I mean your really close to that - whats your humidity high and low?

you using ventilation 24/7?

another thing I have done is put a speed controller on the fan and turn it down while the lights are off - not the most convenient thing to do but got me through a few rainy periods

 

[Critical Kid]

I mean your really close to that - whats your humidity high and low?

you using ventilation 24/7?

During the day humidity is 45-55%
At night 60-75%

I have my in & out fan's set to turn off when the lights turn off. I do this because it is much harder to keep the temperature up during the night if the fans are on. I do have speed controllers, they are usually on high during the day.

 

[motherlode]

yeah if you turn of your venting its gonna be much harder to control the humidty

this time of year can be a pain in the ass to get your grow envrionment dialed

you could try a humidtsat controller for your vent fans

 

[Critical Kid]

you could try a humidtsat controller for your vent fans

Sounds expensive!