Flower stage temp issues

Hey everyone, so I recently flipped my plants to 12/12 (3 days ago) and I’ve been experiencing some pretty high night time temps(lights go out at 8:30am-8:30pm) I know I need to keep the temps in the upper 70s during the day and lower 70s/60s at night but it just doesn’t seem possible right now with the current weather in Chicago.

I vegged for 8 1/2 weeks and was really trying to get through as much of August before the flip, but a power outage from a storm kind of forced me to flip my plants…

I’m running my lights during the night time so that I can raise the light output to really see what my 640WATT timber grow lights are made of. I thought by having lights go at at 8:30am I would be able to control the bedroom with just my air conditioner but my old brick and mortar has been taking a beating this summer(need a much stronger ac, currently have 5,000btus) and I’m just getting worried since I am in flower now.

Does anyone know if an environment like this is going to be a huge problem as I progress through flowering? This my first grow ever so I’m learning as I go, but In veg it was a little easier to get by And from what I’ve read, the flowering stage is very sensitive when it comes to environment…
Here’s some photos…

I’m able to control humidity for the most part under 50% but it does spike up for a few minutes when my dehumidifiers automatic pump turns on to empty the bucket. Also speaking of this dehumidifier, I feel like a lot of the heat building up in my grow room has soemthing to do with this because it does blow out fairly warm air, as it’s suppose to I know, but jthat doesn’t help my battle with temps much.

Hey! Plants look absolutely great!!!
If you are having temperature issues flip flop your light cycle. Leave them in darkness for 24 hours and then resume your light cycle at 8:30 pm lights on and 8:30 am lights off. That will definitely get you out of your current predicament

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Or… if at all possible leave your tent open during the lights on?

nice lookin plants, there gonna produce nice big colas. i agree with tommy. i’m starting 6th week flwr. i run 4am on, 4pm off. work dictates that mainly but house runs cooler at night which keeps my temps down during lights off. winter i switch things around. you mentioned RH spikes with dehu. be really mindful of this issue in flower. good luck and you have a great looking setup :+1:

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Hey tommy hope all is well, thanks for the help as always man🙏🏽 I know I said a lot and it may have been a little confusing, but I do already have my light cycle set to come on at 8:30pm and goes off at 8:30am. My daytime temps for my plants im able to get down to 79F but it’s not until about 6 or so hours into the cycle… the high temps during real time day weather is what is messing my night time temps for my plants.

With my lights being off from 8:30am-8;30pm I was hoping I would be able to control the plants night time temps because my lights wouldn’t be on during the actual day. The culprit is my dehumidifier that’s blowing out the hot air. Today my night temps reached their highest so far into my 4 days of flowering at a peak temp of 88.8F I had my RH in the mid 40% area so I decided to turn my dehumid off and give it a cleaning but also mainly to try and lower the high temp.

Turning my dehumidifier off has already lowered my temps by 4 degrees but it also raised my RH by 7%… do you have any more suggestions on how I can figure this? I’m assuming if I had a stronger air conditioner it would be able to accomplish my environment goals but I was hoping to purchase that stronger ac for next season when… here’s my photos from today.

Hey slick, thanks for you response man! Do you have any suggestions for my previous reply on how to get to a better solotuion to solve my issues??

Like what would be more important if I can’t do anything about my temps, sacrificing high temps for stable RH or sacrificing RH for lower temps…?

can you vent the hot air from dehu out of the room ? duct tape and flexible ducting taped to the backside/exhaust somehow ?
can you blow cool air directly into tent from AC unit ?
can you pull cooler air into lung room ?
how many oscillating fans ? i have 4 in a 3x3x7, only run 2 steady, 3rd for watering day and 4th for backup… i don’t like mold.

keep your humidity in control for sure !!!
i’m a cold weather grower, MN basement. maybe someone here has better ideas to combat heat. gl

Fellow Chi grower here, concur with Slick about venting the warm dehumidifier air. In addition, take a closer look at your ventilation in general. I like to oversize exhaust fans to increase air flow out of the tent while reducing strain on the fan, but sometimes active intake makes sense to maximize air flow and reduce load on exhaust. In a 2 x 2.5 tent I have six-inch sections of duct on two separate air outlets at ground level (covered on external side with thin filter material to block insects/light) which, though passive, helps reduce load on exhaust fan and contributes to a more efficient ventilation.

Those plants are looking fine!

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