"Mystery" temperature rise, what am I missing here? 🤔

[Grownsince95]

*warning* this may be a TLDR post..

The situation: Running three tents in a 8x10 room all with passive intake. The flower tent exausts to outside, the other two back into the room. The room itself has it's own exaust fan to outside running 24/7.
All three tents have different light cycles staggered on and off at different times in an attempt to reduce temp and rh swings. This past week the temps outside dropped quite a bit. The lung room does not have a separate heat control, it is regulated by the apt thermostat. I was watching at night closely because there were some dips down to the low sixties. All except for the flower tent. While all the other temps in the room were falling, the flower tent begins to rise. I have a good graph so we can see it happen and maybe there's some farmers willing to help me crack the code on this one..?

The graph goes back in time from right to left, pic taken 9 am where the 0 is. Bottom #s are hrs ago.
From top to bottom:
Yellow- flower tent
Green- veg tent
Purple- auto tent
Blue- veg tent intake/floor
Red- lung room

Please help me crack the code on this one. All I can come up with is that the building heat would kick in at around 5am when the rise starts but it's only happening inside the tent

What the heck am I missing?

 

[TripsRabbit]

Your flowering plants are putting off humidity, humid air holds heat better than dry air. You should really have a dehumidifier in the flowers tent, 66% humidity is bud rot zone.

 

[TripsRabbit]

Actually by the chart your vpd is right on.

 

[MIMedGrower]

Actually by the chart your vpd is right on.

Too bad the chart doesnt save us from mold and pm. Stupid chart! :-)

 

[Grownsince95]

Too bad the chart doesnt save us from mold and pm. Stupid chart! :-)

Definitely not worried about PM at this stage and there is a dehum in the tent

 

[Grownsince95]

65% lights off doesn't bother me when lights on is 55%. It's the swings that get ya. ❤❤

 

[Grownsince95]

It's bothering me because the data tells me it's isolated to inside the tent.

Where are my gurus at? @Aqua Man @One drop @Dirtbag @Frankster @Hortulanus @amekins @Chad.Westport @Milson ???

 

[Chad.Westport]

Curious if plant respiration has anything to do with added heat in relation to humidity.

 

[Grownsince95]

@growsince79

 

[Grownsince95]

Your flowering plants are putting off humidity, humid air holds heat better than dry air. You should really have a dehumidifier in the flowers tent, 66% humidity is bud rot zone.View attachment 1052174

I think it's the other way around

 

[Grownsince95]

Current situation 12 hrs later...

You can see how everything moves with the lung room usually.

Idk...will take another peek at 9am

 

[One drop]

I’m having a little of the same trouble in my grow lungs .

 

[BurnzYzBudZz]

65% lights off doesn't bother me when lights on is 55%. It's the swings that get ya. ❤❤

That’s not a bad swing at all. What’s the problem?

 

[Grownsince95]

Curious if plant respiration has anything to do with added heat in relation to humidity.

I don't think so, I could be wrong. The dehumidifier is definitely adding heat, but why an extra three degrees? It's a really small vivosun peltier process model, and it couldn't suck a raindrop out of a thunderstorm if it wanted to. It's basically there for emergencies. The only difference in anything that's going on when the temp rises are that the three 75 watt lights in the other tents turn off. Power issue? idk

 

[Grownsince95]

That’s not a bad swing at all. What’s the problem?

Not really a problem yet but having an environmental parameter out of my control bothers me. I can only visit my grow once a week sometimes and it's maddening to watch it unfold from the cameras. Then I only have a day or two to solve the problem sometimes.

I'm getting to that point in flowering where things could get dicey soon.

 

[TripsRabbit]

Why do you ask for help if you are just gonna be a jerk. I know for a fact from experience that a flowering plant in a tent respirates more than a veg plant especially at night. I also know from experience that humid air is harder to cool and keep cool. See if Google can tell you that.

 

[TripsRabbit]

My humidity dropped by 10% and stayed there all day when I unplugged my dehumidifier, explain that.

 

[Grownsince95]

Why do you ask for help if you are just gonna be a jerk. I know for a fact from experience that a flowering plant in a tent respirates more than a veg plant especially at night. I also know from experience that humid air is harder to cool and keep cool. See if Google can tell you that.

The flowering plants in question were not in their night cycle, that's part of the reason why im stumped. The tent is usually very steady with the lights on.
My "Google" comment was also swiftly deleted when I realized how "jerky" it sounded, my apologies that you read it first

I also have no idea why your RH goes up when you unplug your humidifier either.

❤❤

 

[CF89]

A common misunderstanding is that the transpiration of plants will affect the humidity in a grow room. In reality, that’s backwards-using the knowledge that the room conditions affect the plants ability to transpire rather than the plants transpiration affecting the room condition.

Also. Regarding vpd and flowering. Seems like it uses different rates and you might not want to follow the green in the chart during flower

 

[Grownsince95]

Yes the room conditions will influence the plants rate of transpiration or whatever they call it. That only speeds up or slows down the amount of moisture the leaves will contribute to the growth area. Those 2 things can both exist at the same time it's not one way or the other. Saying that plant's leaves are not releasing moistre into the atmosphere around them is just trying to dispute science.

90% of the water we give our plants gets released into the air unused by the plant.